ARTICLE | doi:10.20944/preprints202106.0170.v1
Subject: Life Sciences, Microbiology Keywords: dromedary camels, ticks, heartwater, zoonosis, tick-borne pathogens, Anaplasma, Coxiella, Ehrlichia, Rickettsia
Online: 7 June 2021 (12:39:26 CEST)
Ticks and tick-borne pathogens (TBPs) are major constraints to camel health and production, yet epidemiological data on their diversity and impact on dromedary camels are limited. We sur-veyed the diversity of ticks and TBPs associated with camels and co-grazing sheep at 12 sites in Marsabit County, northern Kenya. We screened blood and ticks (858 pools) collected from 296 camels and 77 sheep for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. Hyalomma (75.7%), Amblyomma (17.6%) and Rhipicephalus (6.7%) spp. ticks were morphologically identified and confirmed by molecular analyses. We detected TBP DNA in 80.1% of blood samples from 296 healthy camels. “Candidatus Anaplasma camelii”, “Candidatus Ehrlichia regneryi” and Coxiella burnetii were detected in both camels and associ-ated ticks, and Ehrlichia chaffeensis, Rickettsia africae, Rickettsia aeschlimannii and Coxiella endo-symbionts were detected in camel ticks. We also detected Ehrlichia ruminantium, responsible for heartwater disease in ruminants, in Amblyomma ticks infesting camels and sheep and in sheep blood, indicating its endemicity in Marsabit. Our findings also suggest that camels and/or the ticks infesting them are reservoirs of zoonotic Q fever (C. burnetii), ehrlichiosis (E. chaffeensis), and rickettsiosis (R. africae), which pose a public health threat to pastoralist communities.
CASE REPORT | doi:10.20944/preprints202212.0041.v1
Subject: Medicine & Pharmacology, Other Keywords: tick-borne encephalitis; tick; Serbia; Switzerland; fatal
Online: 2 December 2022 (07:14:48 CET)
Tick-borne encephalitis (TBE) is vaccine-preventable neglected zoonotic neuroinvasive disease, caused by tick-borne encephalitis virus (TBEV). Many of the Central and Eastern European countries are affected by TBE, which is often poorly perceived by tourists visiting endemic territories. Here we are reporting a fatal case of imported TBE in Serbian resident who was exposed to tick bite during a visit to Switzerland.
COMMUNICATION | doi:10.20944/preprints202009.0715.v1
Subject: Medicine & Pharmacology, Allergology Keywords: dog; ehrlichiosis; ELISA; Tick-borne; TRP19; TRP36
Online: 29 September 2020 (14:38:27 CEST)
Tandem repeat proteins of 36 kDa (TRP36) are major immunoreactive proteins of Ehrlichia canis, which have been used in the serological diagnosis of different genotypes of the microorganism. The aim of this study was to evaluate the distribution of the American (USTRP36), Brazilian (BrTRP36) and Costa Rican (CRTRP36) genotypes of E. canis in Brazil, using ELISA assays. Serum samples of 815 dogs from 49 cities from all over Brazil were analyzed. Our results showed that 33.9% of the samples were reactive to the USTRP36 genotype and 32.6% to the BrTRP36 genotype. The two genotypes appeared to occur equally throughout Brazil, although the frequency of seropositivity was lower in the south than in the country’s other regions. Co-positivity for the American and Brazilian genotypes was also observed in 16% of samples. A few dogs (n=5; 0.6%) reactive to E. canis-TRP36 genotype (CRTRP36) were also detected in the northeast and southern regions. We conclude that the American and Brazilian genotypes of E. canis are distributed evenly in Brazil, especially in the tropical region, while the temperate region in the south presented the lowest prevalence values. This study offers the first report of dogs seropositive for the Costa Rican genotype in Brazil.
ARTICLE | doi:10.20944/preprints202002.0136.v1
Subject: Life Sciences, Virology Keywords: tick-borne encephalitis; vaccination; NS1; vaccine; flavivirus
Online: 11 February 2020 (09:10:41 CET)
Vaccination against tick-borne encephalitis (TBE) is based on the use of formalin-inactivated, culture-derived whole-virus vaccines. Immune response following vaccination is primarily directed to the viral envelope (E) protein, the major viral surface antigen. In Europe, two TBE vaccines are available in adult and pediatric formulations, FSME-IMMUN® (Pfizer) and Encepur® (GlaxoSmithKline). Herein, we analyzed the content of these vaccines using mass spectrometry (MS). The MS analysis revealed that the Encepur vaccine contains not only proteins of the whole virus particle, but also viral non-structural protein 1 (NS1). MS analysis of the FSME-IMMUN vaccine failed due to the high content of human serum albumin used as a stabilizer in the vaccine. However, the presence of NS1 in FSME-IMMUN was confirmed by immunization of mice with six doses of this vaccine, which led to a robust anti-NS1 antibody response. NS1-specific western blot analysis detected anti-NS1 antibodies also in sera of humans who received multiple doses of either of these two vaccines; however, most vaccinees who received ≤3 doses were negative for NS1-specific antibodies. The contribution of NS1-specific antibodies to protection against TBE was demonstrated by immunization of mice with purified NS1 antigen, which led to a significant (p < 0.01) prolongation of the mean survival time after lethal virus challenge. This indicates that stimulation of anti-NS1 immunity by the TBE vaccines may increase their protective effect.
COMMUNICATION | doi:10.20944/preprints202206.0038.v1
Subject: Life Sciences, Virology Keywords: tick-borne encephalitis virus; vaccine; non-structural protein 1
Online: 3 June 2022 (09:48:01 CEST)
The presence of a non-structural protein 1 (NS1) in tick-borne encephalitis (TBE) vaccines and the possible induction of an NS1-specific immune response in vaccinated individuals remains a somewhat controversial topic. Previously, we detected the presence of NS1 in Encepur TBE vaccine by mass spectrometry and found the induction of NS1-specific IgG antibodies in mice vaccinated with FSME-Immun TBE vaccine. Here, in this follow-up study, we examined the dynamics and extent of the NS1-specific IgG response in mice vaccinated with these two vaccines in more detail and compared it with the IgG response to the whole virus (WV). Mice were vaccinated at two-week intervals with a total of six doses of each vaccine, and levels of IgG antibodies to TBE virus WV and NS1 were measured by ELISA after each dose. Both vaccines elicited a robust anti-WV IgG response after two doses. The Encepur vaccine did not elicit NS1-specific IgG even after all six doses. In contrast, FSME-Immun vaccine triggered production of NS1-specific IgG after four doses. The results indicate that FSME-Immun is the only vaccine that elicits an NS1-specific antibody response in mice. However, compared to WV-specific IgG, the NS1-specific response is weaker, and a higher number of doses is required to induce detectable levels of NS1-specific IgG antibodies.
ARTICLE | doi:10.20944/preprints202204.0087.v1
Subject: Life Sciences, Microbiology Keywords: Rickettsia parkeri; Rhipicephalus sanguineus; dogs; tick-borne disease; rickettsiosis
Online: 11 April 2022 (03:37:16 CEST)
Of the documented tick-borne diseases infecting humans in Mexico, Rocky Mountain spotted fever (RMSF), caused by the gram-negative bacterium Rickettsia rickettsia, is responsible for most fatalities. Given recent evidence of brown dog tick, Rhipicephalus sanguineus sensu lato, as an emerging vector of human RMSF, we aimed to evaluate dogs and their ticks for rickettsiae infections as an initial step in assessing the establishment of this pathosystem in a poorly studied region of northeastern Mexico while evaluating the use of dogs as sentinels for transmission/human disease risk. We sampled owned dogs living in six disadvantaged neighborhoods of Reynosa, Northern Mexico to collect whole blood and ticks. Of 168 dogs assessed, tick infestation prevalence was 53%, comprised of exclusively R. sanguineus s. l. (n=2,170 ticks). Using PCR and sequencing, we identified an overall rickettsiae infection prevalence of 4.1% (n=12/292) in ticks, in which eight dogs harbored at least one infected tick. Rickettsiae infections included R. amblyommatis and R. parkeri, both of which are emerging human pathogens, as well as candidatus R. andeanae. This is the first documentation of pathogenic Rickettsia in R. sanguineus s.l. collected on dogs from northeastern Mexico. Domestic dog infestation with Rickettsia-infected ticks indicates ongoing transmission, thus humans are at risk for exposure and underscores the importance of public and veterinary health surveillance for these pathogens.
Subject: Medicine & Pharmacology, Veterinary Medicine Keywords: Coxiella burnetii; Rickettsia; Q fever; rickettsiosis; tick-borne pathogens
Online: 31 March 2020 (09:54:07 CEST)
Rickettsia and Coxiella burnetii are zoonotic tick-borne pathogens that can cause febrile illnesses with or without other symptoms in humans but may cause subclinical infections in animals. There are only a few reports on the occurrence of these pathogens in cattle and water buffaloes in Southeast Asia, including the Philippines. In this study, molecular detection of Rickettsia spp. and C. burnetii in the blood and Rhipicephalus (Boophilus) microplus ticks of cattle and water buffaloes from five provinces in Luzon Island of the Philippines was done. A total of 620 blood samples of cattle and water buffaloes and 206 tick samples were collected and subjected to DNA extraction. After successful amplification of control genes, nested PCR was performed to detect gltA of Rickettsia and com1 of C. burnetii. No samples were positive for Rickettsia while 10 (cattle – 7, water buffaloes - 3) or 1.6% of blood and 5 or 1.8% of tick samples were C. burnetii-positive. Sequence analysis of the positive amplicons showed 99-100% similarity to reported C. burnetii isolates. This molecular evidence on the occurrence of C. burnetii in Philippine ruminants and cattle ticks and its zoonotic nature should prompt further investigation and surveillance to facilitate its effective control.
COMMUNICATION | doi:10.20944/preprints202201.0462.v1
Subject: Biology, Animal Sciences & Zoology Keywords: roe deer; Tick-Borne Encephalitis; neurologic disease; pathology; genetic characterization
Online: 31 January 2022 (13:21:18 CET)
Tick borne encephalitis virus (TBEV) is the causative agent of Tick borne encephalitis in humans, a severe zoonosis occurring in the Paleartic region mainly transmitted through ticks belonging to the genus Ixodes. In Italy, TBEV is restricted to few foci in the north-eastern part of the country. This report describes for the first time a case of clinical TBE in a roe deer, occurred in the Belluno province, Veneto region, an area highly endemic for the presence of the virus. The affected roe deer showed ataxia, staggering movements, muscle tremors and persistent teeth grinding causing hypersalivation. At necropsy, the macroscopic picture was inconclusive. RNA of TBEV was detected by real-time RT-PCR. Phylogenetic analysis revealed a close relationship to TBEV of the European subtype, and 100% similarity with a virus from the bordering Trento Province. The histological examination of the midbrain confirmed the viral etiology and specific immunofluorescence indicated the presence of a Flavivirus infection and characterized the pattern of infection in the neurons. This report underlines for the first time the occurrence of clinical encephalitic manifestations due to TBEV in a roe deer, thussuggesting to include this pathogen in the frame of differential diagnosis in this species.
ARTICLE | doi:10.20944/preprints202209.0024.v1
Subject: Life Sciences, Virology Keywords: flavivirus; tick-borne encephalitis; electron microscopy; EELS; nanoparticle tracking analysis; cryo-EM
Online: 1 September 2022 (10:54:41 CEST)
Tick-borne encephalitis virus (TBEV) is a RNA-containing enveloped virus, a member of the Flaviviridae family. Here we describe a detailed analysis of the size and structure of inactivated TBEV (the Sofyin-Chumakov TBEV strain, used in vaccines). Four analytical methods were used to analyze individual TBEV particles—negative staining TEM, cryo-EM, AFM, and NTA. All methods confirmed that the particles were monodisperse, and their mean size was ~50 nm. Cryo-EM data were used to obtain a 3D electron density model of the virus with clearly distinguishable E-proteins. STEM-EELS analysis detected phosphorous in the particles, which was interpreted as the RNA signal. Altogether, the described analytical procedures can be valuable for the further analysis of vaccine inactivated virus samples.
REVIEW | doi:10.20944/preprints202212.0573.v1
Subject: Biology, Other Keywords: Borrelia miyamotoi, Ixodes, Lyme disease, relapsing fever, reservoir species, tick-borne disease, vector
Online: 30 December 2022 (08:08:13 CET)
Borrelia miyamotoi is an emerging tick-borne pathogen in the Northern hemisphere and is the causative agent of Borrelia miyamotoi disease (BMD). B. miyamotoi is vectored by the same hard-bodied ticks as Lyme disease Borrelia, yet phylogenetically groups with relapsing fever Borrelia, and thus has been uniquely labeled a hard tick-borne relapsing fever Borrelia. Burgeoning research has uncovered new aspects of B. miyamotoi in human patients, nature, and the lab. Of particular interest are novel findings on disease pathology, prevalence, diagnostic methods, ecological maintenance, transmission, and genetic characteristics. Herein we review recent literature on B. miyamotoi, discuss how findings adapt to current Borrelia doctrines, and briefly consider what remains unknown about B. miyamotoi.
ARTICLE | doi:10.20944/preprints202011.0543.v1
Subject: Life Sciences, Biochemistry Keywords: Francisella tularensis; Dermacentor variabilis; Amblyomma americanum; Haemaphysalis longicornis; tick-borne disease; Tularemia; Chitinase
Online: 20 November 2020 (12:21:26 CET)
Tick-borne tularemia was first described in 1924. Nearly 100 years later, questions remain about the tick vector(s) that pose(s) the greatest risk for transmitting Francisella tularensis (Ft), the causative agent of tularemia. Additionally, few studies have identified genes/proteins required for Ft to infect, persist, and replicate in ticks. To answer questions about vector competence and Ft transmission by ticks, we infected Dermacentor variabilis (Dv), Amblyomma americanum (Aa), and Haemaphysalis longicornis (Hl; invasive species from Asia) ticks with Ft, finding that although Aa ticks initially become infected with 1-log higher Ft, Ft replicated more robustly in Dv ticks, and did not persist in Hl ticks. In transmission studies, both Dv and Aa ticks efficiently infected naïve mice, causing disease in 57% and 46% of those mice, respectively. We identified a putative Ft chitinase, FTL1793, generated a FTL1793 mutant, and found that FTL1793 was deficient in tick infection, persistence, and replication in ticks. Recombinant FTL1793 exhibited chitinase activity in vitro, suggesting that this chitinase may provide an alternative energy source for Ft in ticks. Taken together, Dv ticks appear to pose a greater risk for harboring and transmitting tularemia and FTL1793 plays a major role in promoting tick infections by Ft.
ARTICLE | doi:10.20944/preprints202211.0315.v1
Subject: Biology, Other Keywords: Tick-borne encephalitis virus; Yellow fever virus; vaccine strain; chimeric virus; infectious subgenomic amplicons; candidate vaccines
Online: 16 November 2022 (16:35:12 CET)
Tick-borne encephalitis virus (TBEV) is one of the most threatening pathogens which affects the human central nervous system (CNS). TBEV circulates widely in Northern Eurasia. According to ECDC the number of TBE cases increase annually. There is no specific treatment for the TBEV infection, thus vaccination is the main preventive measure. Despite the existence of several inactivated vaccines currently being licensed, the development of new TBEV vaccines remains a leading priority in countries endemic to this pathogen. Here we report new recombinant virus made by infectious subgenomic amplicon (ISA) approach using TBEV and yellow fever virus vaccine strain (YF17DD-UN) as a genetic backbone. The recombinant virus is capable of effective replication in mammalian cells and induce TBEV-neutralizing antibodies in mice. Unlike the original vector based on the yellow fever vaccine strain chimeric virus became neuroinvasive in doses of 107-106 PFU and can be used as a model of Flavivirus neuroinvasiveness, neurotropism and neurovirulence. These properties of hybrid structures are the main factors limiting their practical use as vaccines platforms.
ARTICLE | doi:10.20944/preprints202204.0001.v1
Subject: Biology, Other Keywords: tick-borne encephalitis virus; cryo-electron microscopy; TBEV; envelope protein; membrane protein; lipid factor; glycoprotein; quasi-equivalence
Online: 1 April 2022 (03:24:38 CEST)
Tick-borne encephalitis virus (TBEV) is a pathogenic, enveloped, positive-stranded RNA virus in the family Flaviviridae. Structural studies of flavivirus virions have primarily focused on mosquito-borne species with only one cryo-electron microscopy (cryo-EM) structure of a tick-borne species published. Here, we present a 3.3 Å cryo-EM structure of the TBEV virion of the Kuutsalo-14 isolate, confirming the overall organisation of the virus. We observe conformational switching of the peripheral and transmembrane helices of M protein, which can explain the quasi-equivalent packing of the viral proteins and highlights their importance in stabilizing the membrane protein arrangement in the virion. The residues responsible for the M protein inter-actions are highly conserved in TBEV but not in the structurally studied Hypr strain, nor in mosquito-borne flaviviruses. These interactions may compensate for the lower number of hydrogen bonds between E proteins in TBEV compared to the mosquito-borne flaviviruses. The structure reveals two lipids bound in the E protein, which are important for virus assembly. The lipid pockets are comparable to those recently described in mosquito-borne Zika, Spondweni, Dengue, and Usutu viruses. Our results thus advance the understanding of tick-borne flavivirus architecture and virion-stabilising interactions.
ARTICLE | doi:10.20944/preprints201806.0299.v1
Subject: Life Sciences, Virology Keywords: Crimean-Congo hemorrhagic fever virus; Crimean-Congo hemorrhagic fever; Hyalomma marginatum; human cutaneous immune response; Langerhans cells; dermal dendritic cells; tick-borne virus; tick-virus-host interface
Online: 19 June 2018 (11:50:54 CEST)
Crimean-Congo hemorrhagic fever virus is one the most important and wide spread tick-borne viruses. Very little is known about the transmission from the tick and the early aspects of pathogenesis. Here, we generate human cutaneous antigen presenting cells: dermal dendritic cells and Langerhans cells, from umbilical cord progenitor cells. In order to mimic the environment created during tick feeding, tick salivary gland extract was generated from semi-engorged Hyalomma marginatum ticks. Our findings indicate that human dermal dendritic cells and Langerhans cells are susceptible and permissive to Crimean-Congo hemorrhagic fever virus infection, however, to different degrees. Infection leads to cell activation and cytokine/chemokine secretion, although these responses vary between the different cell types. Hyalomma marginatum salivary gland extract had minimal effect on cell responses, with some synergy with viral infection with respect to cytokine secretion. However, salivary gland extract appeared to inhibit antigen presenting cell (APC) migration. Based on the findings here we hypothesize that human dermal dendritic cells and Langerhans cells serve as early target cells. Rather affecting Crimean-Congo hemorrhagic fever virus replication, tick saliva likely immunomodulates and inhibits migration of these APC from the feeding site.
ARTICLE | doi:10.20944/preprints202007.0156.v1
Subject: Medicine & Pharmacology, Veterinary Medicine Keywords: canine vector-borne diseases; mosquito-borne diseases; dirofilariosis; ehrlichiosis; leishmaniosis; dogs; multi-modal prophylaxis; Corsica
Online: 8 July 2020 (12:03:53 CEST)
With a mild Mediterranean-type climate, Corsica is endemic for canine vector-borne diseases (CVBDs) such as dirofilariosis (a mosquitoes borne-diseases: MBDs), leishmaniosis and ehrlichiosis. The aim of this present study was to evaluate a monthly multi-modal prophylactic strategy (MMP) against CVBDs occurring in Corsica. The study was conducted as a comparative field trial in which eighty dogs allocated into two groups were included: (i) Group 1 consisted of 25 dogs under the MMP [per-os administration of 1.5 tablet of milbemycine oxime-praziquantel and a topical line-on application of a 3.6 mL solution of dinotefuran-permethrin-pyriproxyfen] and (ii) Group 2 under various real-life prophylactic treatment (RLP) based on the use of ectoparasiticide products [different formulations: deltamethrin, fluralaner, fipronil] and/or macrocyclic lactones based-products [milbemycin oxime/praziquantel, milbemycin oxime, moxidectin] during the period ranging from June to October 2017. All animals were followed for one year and had blood drawn at day 0, followed by follow-up at 6 and 12 months. Samples were screened for filariosis using molecular tools as well as for leishmaniosis and ehrlichiosis using indirect immunofluorescence assay (IFA). At the end of the study, no new cases of CVBDs were recorded within Group 1. In Group 2, the cumulative incidence of CVBDs was 20.0% (n= 11; p= 0.015) including dirofilarioses due to Dirofilaria immitis and/or D. repens, with 16.4% (n= 9; p=0.027). Ehrlichiosis was 5.5% (n= 3; p=0.241). No new cases of leishmaniosis were detected in Group 2. The data illustrated that, unlike the RLP treatment which failed to protect at least 20% of dogs, the MMP based on the concurrent administration of milbemycine oxime-praziquantel and dinotefuran-permethrin-pyriproxyfen is efficient to protect dogs against CVBDs in a high-risk area.
ARTICLE | doi:10.20944/preprints202203.0250.v1
Subject: Medicine & Pharmacology, Veterinary Medicine Keywords: Tick bites; Ixodidae; epidemiology: emerging diseases; Spain
Online: 17 March 2022 (10:18:51 CET)
Ticks drive a wide diversity of pathogens to a great variety of hosts, including humans. We conducted a tick surveillance study in northwestern Spain between 2014 and 2019. Ticks were removed from people and were identified. Tick numbers, species, development stages, evolution over time, seasonal and geographical distribution, and epidemiological characteristics of people bitten by ticks were studied. We collected ticks from 8143 people. Nymphs of Ixodes ricinus were the most frequently collected. Rhipicephalus bursa, Rhipicephalus sanguineus sensu lato (s.l), Hyalomma marginatum, Hyalomma lusitanicum, Dermacentor marginatus, Dermacentor reticulatus and Haemaphysalis punctata were also found, with adults as the main stage. Hyalomma spp. and R. bursa have been progressively increasing over time. Although bites occurred throughout the year, the highest number of incidents were reported from April to July. The distribution patterns of the tick species were different between the north and the south of the region, which was related to cases detected in humans of the pathogens they carried. Adult men were more likely to be bitten by ticks than women. Ticks were most frequently removed from adults from the lower limbs, while for children they were mainly attached to the head. Epidemiological surveillance is essential given the increase in tick populations in recent years, mainly of species potentially carrying pathogens causing emerging diseases in Spain, such as the Crimean Congo Hemorraghic Fever (CCFH).
ARTICLE | doi:10.20944/preprints202107.0615.v1
Subject: Life Sciences, Biochemistry Keywords: Babesiosis; Cattle; Host factors; Prevalence; Tick infestation; South Omo
Online: 28 July 2021 (09:05:24 CEST)
Background: Babesiosis and its tick carriers cause serious problems for cattle and are among the common protozoan blood parasites in Ethiopia. Methods: A cross-sectional survey was conducted from September 2019 to August 2020 to identify babesiosis in cattle and its tick vectors in extensively managed livestock in Dasenech and Salamago District South Omo Ethiopia. A total of 470 blood samples were collected for identification of hemoparasite using a thin blood smear followed by the Giemsa staining method and Packed Cell Volume (PCV) determination for detection of anemia. Results: Accordingly, the overall prevalence of bovine babesiosis in the study districts were 21.7% and Babesia bigemina (15.53%) and B. bovis (6.17%) were identified during this study. Factors such as age, sex, body condition score, season, tick burden, and level of tick Infection were considered as risk factors; yet, the season and level of tick Infection were found significantly associated (p< 0.05) with the occurrence of babesiosis. Besides, the mean PCV value of infected cattle (21.49%) was lower than non-infected animals (28.29%) which shows there was a strong correlation (p=0.0001) between anemia and Babesiosis. The prevalence of tick Infection was 86.17% (405/470) and a total of 8040 ticks adult ticks belonging to four tick genera namely Amblyomma (32.34%), Boophilus (18.51%), Hyalomma (18.94%), and Rhipicephalus (16.38%) were identified and all have a significant role (p< 0.05) on the occurrence of babesiosis in cattle. Conclusion: Bovine babesiosis is an important hemoparasitic protozoan disease of cattle in the study areas. To address and manage the problem, nearby veterinary service systems need to diagnose blood parasites and provide alternatives, especially for tick-borne diseases. Also, it is essential to customize appropriate and integrated tick control measures and tactical treatment of overt bovine babesiosis clinical cases.
BRIEF REPORT | doi:10.20944/preprints202010.0121.v1
Subject: Life Sciences, Biochemistry Keywords: Q fever; tick, meso-Mediterranean; transstadial transmission; artificial feeding
Online: 6 October 2020 (11:04:29 CEST)
Coxiella burnetii (Derrick) Philip, the causative agent of Q fever, is mainly transmitted by aerosols, but ticks can also be a source of infection. Transstadial and transovarical transmission of C. burnetii by Hyalomma lusitanicum (Koch) has been suggested. There is a close relationship between this tick species, wild animals and C. burnetii but the transmission in a natural environment has not been demonstrated. In this study, we collected 80 engorged nymphs of H. lusitanicum from red deer and wild rabbits. They molt to adults under laboratory conditions and we feed them artificially through silicone membranes after a preconditioning period. C. burnetii DNA was tested in ticks, blood and feces samples using real-time PCR. The pathogen was found in 36.25% of fed adults demonstrating that transstadial transmission from nymph to adult occurs in nature. The presence of DNA in the 60% of blood samples confirms that adults transmit the bacteria during feeding. Further studied are needed about co-feeding and other possible transmission routes to define the role of this tick species in the cycle of C. burnetii.
REVIEW | doi:10.20944/preprints202010.0606.v1
Subject: Biology, Ecology Keywords: virology; emerging viruses; vector-borne diseases; climate change
Online: 29 October 2020 (09:49:40 CET)
Three decades have now passed since the first papers linking climate change to issues in human disease and healthcare. One of the most active topics in this area has been the implication of climate change events, particularly temperature and humidity fluctuations, in the northward spread of vector-borne viruses from more tropical regions into Europe and North America. However, some detailed studies of one such emerging disease, tick-borne encephalitis virus (TBEv), have called the connection into question, concentrating the debate on the investigation of precise mechanisms for the spread of viral disease. More recently, firmer statistical correlations have been made between climate variables, the presence of insect vectors and the prevalence of viral disease, particularly for West Nile Virus (WNV). These insights suggest avenues for mechanistic confirmation of the involvement of climate change in other diseases where the connection remains conjectural.
ARTICLE | doi:10.20944/preprints201910.0103.v1
Subject: Life Sciences, Microbiology Keywords: beta-lactamase; cephalosporin; cefotaxime; transconjugation; plasmid-borne resistance
Online: 9 October 2019 (11:03:44 CEST)
Clinical pathogens especially Gram-negative bacteria developing resistance to third-generation cephalosporins are making the clinical outcome more complicated and serious. This study was undertaken to evaluate the distribution of extended-spectrum beta-lactamases in Tamil Nadu regions in India. For this study, clinical samples were collected from five different hospitals located in Tamil Nadu and ESBL producing Gram-negative isolates were characterized. Minimal inhibitory concentration (MIC) was performed using cefotaxime and ceftazidime. The blaESBL producing genes were screened using multiplex PCR for the genes, CTX-M group-1,-2,-8,-9,-26. Conjugation studies were performed using E. coli AB1157 as a recipient for the isolates harbouring plasmid-borne resistance following broth-mating experiment. In total, 1500 samples were collected and 599 Gram-negative bacteria were isolated that included Escherichia coli (n=233), Klebsiella pneumoniae (n=182), Pseudomonas aeruginosa (n=79), Citrobacter spp. (n=30), Proteus mirabilis (n=28), Salmonella spp. (n=21), Acinetobacter baumannii (n=12), Serratia spp. (n=6), Shigella spp. (n=4), Morganella morganii (n=3) and Providencia spp. (n=1). MIC results showed that 358 isolates were resistant to cefotaxime and ceftazidime. Further, ESBL gene amplification results showed that 19 isolates had CTX-M group-1 gene including E. coli (n=16), K. pneumoniae (n=2) and P. aeruginosa (n=1) whereas one M. morganii isolate had CTX-M group-9 gene in their plasmid. Through conjugation studies, 12/20 isolates were found to be involved in the transformation of its plasmid-borne resistance gene. Our study highlighted the role of horizontal gene transfer in the dissemination of plasmid-borne blaCTX-M resistance genes among ESBL producing isolates.
REVIEW | doi:10.20944/preprints201811.0107.v1
Subject: Engineering, Construction Keywords: Built Environment, Design Decisions, Vector Borne Diseases, Malaria
Online: 5 November 2018 (11:01:08 CET)
Although significant efforts have been made to combat the spread of vector-borne diseases (VBDs), they still account for more than 17% of all infectious diseases. According to the World Health Organization (WHO), there were 216 million estimated cases in 2016, which is a 9.3% decrease from the estimated cases reported one decade earlier. It is known that the built environment, through features such as openings, can propagate the spread of malaria. There have been some significant efforts directed at addressing this risk. This notwithstanding, there are some knowledge gaps that have resulted in a missed opportunity for synergistically tackling the problem of vectors through leveraging design decisions made by built environment professionals. This work assesses the extent to which design decisions in the built environment can have a positive impact on the efforts directed at mitigating the risk of malaria based on selected cases from East Africa. Secondary data derived from relevant urban health journals as well as repositories curated by leading health agencies such as WHO were synthesized and analyzed using a web of causation approach. The outcome of the analysis is a schema of primary and secondary source (risk) factors. The use of the web of causation approach revealed the existing factor-to-factor interactions that could have a reinforcing effect. This information was used to identify the critical linkages and interdependencies across different factors. The outcome of the analysis was mapped against risk factors that can be linked to decisions made during the six primary phases of the construction life cycle: preliminary phase, conceptual design, detailed design, construction, facilities management, and end of life/disuse. The findings of the research have established that 1) there is, in fact, a built environment–related opportunity that can be leveraged to advance the impact of malaria mitigation effort; 2) cross-disciplinary synergies are critical to managing the interdependencies and complexity of malaria risk factors that have a reinforcing effect; and 3) a knowledge-management framework that serves as a decision support tool would be valuable for sharing data under a push-and-pull mechanism, in which data shared in real time can address the timeliness of mitigating the spread of malaria at the earliest stages for the greatest impact. Based on the findings, a conceptual architecture for a decision support framework has been proposed. This will be developed into a knowledge-management platform in subsequent efforts.
REVIEW | doi:10.20944/preprints201807.0378.v1
Subject: Life Sciences, Virology Keywords: Yellow fever virus; flavivirus; vector-borne transmission, emergence
Online: 20 July 2018 (05:54:00 CEST)
As revealed by the recent resurgence of yellow fever virus (YFV) activity in the tropical regions of Africa and South America, YFV control measures need urgent rethinking. Over the last decade, most reported outbreaks occurred in, or eventually reached, areas of low vaccination coverage but suitable for virus transmission, with an unprecedented risk of expansion to densely populated territories in Africa, South America and Asia. As reflected in the World Health Organization’s initiative launched in 2017, it is high time to strengthen epidemiological surveillance to monitor accurately, viral dissemination and redefine vaccination recommendation areas. Vector-control and immunisation measures need to be adapted and vaccine manufacturing must be reconciled with an increasing demand. We will have to face more YF cases in the upcoming years hence, improving disease management through the development of efficient treatments will prove most beneficial. Undoubtedly, these developments will require in-depth descriptions of YFV biology at molecular, physiological and ecological levels. This second section of the two-part review describes the current state of knowledge and gaps regarding the molecular biology of YFV, along with an overview of the tools that can be used to manage the disease at the individual, local and global levels.
REVIEW | doi:10.20944/preprints201805.0099.v1
Subject: Life Sciences, Virology Keywords: yellow fever virus; Flavivirus; vector-borne transmission, emergence
Online: 7 May 2018 (05:19:50 CEST)
The recent resurgence of yellow fever virus (YFV) activity in the tropical regions of Africa and South America has sparked renewed interest in this infamous arboviral disease. YFV had been a human plague for centuries prior to the identification of its urban transmission vector, the Aedes aegypti mosquito species, and the development of an efficient live-attenuated vaccine, the YF-17D strain. The combination of vector-control measures and vaccination campaigns drastically reduced YFV incidence in humans on many occasions, but the virus never ceased to circulate in the forest, through its sylvatic invertebrate vector(s) and vertebrate host(s). Outbreaks recently reported in Central Africa (2015-2016) and Brazil (since late 2016), reached considerable proportions in terms of spatial distribution and total numbers of cases, with multiple exports, including to China. In turn, questions regarding the likeliness of occurrence of large urban YFV outbreaks in the Americas or of a successful import of YFV to Asia are currently resurfacing. This two-part review describes the current state of knowledge and gaps regarding the molecular biology and transmission dynamics of YFV, along with an overview of the tools that can be used to manage the disease at the individual, local and global levels.
ARTICLE | doi:10.20944/preprints201801.0142.v2
Online: 8 February 2018 (15:21:11 CET)
Since the water-borne iodine excessive goiter was firstly found and reported in 19 in Hebei Province, it was confirmed successively. The national water-borne investigation carried out in 2005 demarcated the water-borne iodine excess areas and water-borne iodine excess endemial areas. The high iodine water well was found In 129 counties of 11 provinces, about 30.98 million people of threatened population lived in water-borne iodine excess areas and water borne iodine excess endemial areas. In these areas, the measures of prevention and control was effectively implemented. In 2016, the new standard of iodine excess area was issued, the iodine excess areas redrawed, and in these areas, non-iodized salt should be supplied and the drinking water should be gradually improved of water, and to control the damage of water-borne iodine excess at an early date
ARTICLE | doi:10.20944/preprints202203.0387.v1
Subject: Life Sciences, Biochemistry Keywords: Asian longhorned tick; Haemaphysalis longicornis; Bourbon virus; Emerging arbovirus; Virginia
Online: 30 March 2022 (08:24:04 CEST)
Haemaphysalis longicornis (Neumann, 1901) (Acari: Ixodidae), the Asian longhorned tick, is an invasive tick species present in the USA since at least 2017 and has been detected in one-third of Virginia counties. While this species is associated with the transmission of multiple pathogens in its native geographical range of eastern Asia, little is known about its ability to acquire and transmit pathogens in the USA, specifically those that are transmissible to humans, although from an animal health perspective it has already been shown to vector Theileria orientalis Ikeda strains. Emerging tick-borne viruses such as Bourbon virus (genus: Thogotovirus) are of concern as these newly discovered pathogenic agents have caused fatal clinical cases, and little is known about their distribution or enzootic maintenance. This study examined H. longicornis collected within Virginia (from ten counties) for Bourbon and Heartland virus using PCR methods. All ticks tested negative for Heartland virus via qRT-PCR. Bourbon virus-positive samples were confirmed on two different gene targets, and with Sanger sequencing of the PB2 (segment 1) gene. Bourbon virus RNA was detected in one nymphal stage H. longicornis from Patrick County, one nymph from Staunton City, one larval pool and one adult female tick from Wythe County, Virginia. An additional 100 Amblyomma americanum (Linnaeus 1758; lone star tick) collected at the same Patrick County site revealed one positive nymphal pool, suggesting that Bourbon virus may have spilled over from the native vector, potentially by co-feeding on a shared Bourbon virus-infected vertebrate host. Blood tested from local harvested deer revealed a 12.0% antibody seroprevalence against Bourbon virus, exposure which further corroborates that this tick-borne virus is circulating in the Southwest Virginia region. Through these results it can be concluded that H. longicornis can carry Bourbon virus and that pathogen spillover may occur from native to invasive tick species.
Subject: Life Sciences, Biochemistry Keywords: viral persistence; flaviviruses; mosquito; tick; autophagy; interferon; wildlife; infection; arbovirus
Online: 12 August 2021 (18:28:52 CEST)
A substantial number of humans are at risk for infection by vector-borne flaviviruses, resulting in considerable morbidity and mortality worldwide. These viruses also infect wildlife at a considerable rate, persistently cycling between either the tick or mosquito vector to small mammals (e.g. rodents, skunks) and reptiles to non-human primates and humans. Substantially increasing evidence of viral persistence in wildlife continue to be reported. In addition to in humans, viral persistence can also be established in mammalian, reptile, arachnid, and mosquito systems, as well as insect cell lines in culture. Although a considerable amount of research has focused on the potential roles of defective virus particles, autophagy and/or apoptosis induced evasion of the immune response, the precise mechanism of flavivirus has yet to be elucidated. In this review, we present findings that aid in further understanding of how vector-borne flavivirus persistence is established in wildlife. Research studies to be discussed include determining the critical roles universal flavivirus non-structural proteins played in viral persistence, the development of relevant animal models of viral persistence, and investigating the host responses that allow vector-borne flavivirus replication without destructive effects on infected cells. These findings underscore the viral–host relationships in wildlife animals and could be used to elucidate the mechanisms for the establishment of viral persistence in these animals.
ARTICLE | doi:10.20944/preprints201911.0340.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: synthetic aperture radar (sar); space-borne sar; deceptive jamming
Online: 27 November 2019 (09:49:31 CET)
Due to the advantages such as low power consumption and higher concealment, deceptive jamming against synthetic aperture radar (SAR) receives extensive attention during the past decades. However, the large scene deception jamming is still a challenge because of the huge computing burden. In this paper, we propose a new large scene deceptive jamming algorithm. First, the time-delay and frequency-shift (TDFS) algorithm is introduced to improve the jamming processing speed. The system function of jammer (JSF) for a fake scatter is simplified to the multiplication of the scattering coefficient, a time-delay term in range dimension and a frequency-shift term in azimuth dimension. Then, in order to solve the problem that the effective region of the TDFS algorithm is limited, the scene deceptive jamming template is divided into several blocks according to the SAR parameters and imaging quality control factor. The JSF of each block is calculated by the TDFS algorithm and added together to achieve the large scene jamming. Finally, the correction algorithm in squint mode is derived. The simplification and parallel block processing could improve the calculation efficiency significantly. The simulation results verified the validity of the algorithm.
ARTICLE | doi:10.20944/preprints202006.0141.v1
Subject: Life Sciences, Microbiology Keywords: Wolbachia; tick cell line; Ctenocephalides; flea; Malaysia; in vitro culture; phylogeny
Online: 12 June 2020 (04:51:00 CEST)
Wolbachia are intracellular endosymbionts of several invertebrate taxa, including insects and nematodes. Although Wolbachia DNA has been detected in ticks, its presence is generally associated with parasitism by insects. To determine whether or not Wolbachia can infect and grow in tick cells, cell lines from three tick species, Ixodes scapularis, Ixodes ricinus and Rhipicephalus microplus, were inoculated with Wolbachia strains wStri and wAlbB isolated from mosquito cell lines. Homogenates prepared from fleas collected from cats in Malaysia were inoculated into an I. scapularis cell line. Bacterial growth and identity were monitored by microscopy and PCR amplification and sequencing of fragments of Wolbachia genes. The wStri strain infected Ixodes spp. cells and was maintained through 29 passages. The wAlbB strain successfully infected Ixodes spp. and R. microplus cells and was maintained through 2-5 passages. A novel strain of Wolbachia belonging to the supergroup F, designated wCfeF, was isolated in I. scapularis cells from a pool of Ctenocephalides sp. cat fleas and maintained in vitro through two passages over nine months. This is the first confirmed isolation of a Wolbachia strain from a flea and the first isolation of any Wolbachia strain outside the “pandemic” A and B supergroups. The study demonstrates that tick cells can host multiple Wolbachia strains, and can be added to panels of insect cell lines to improve success rates in isolation of field strains of Wolbachia.
ARTICLE | doi:10.20944/preprints202207.0231.v1
Subject: Life Sciences, Virology Keywords: Mosquito; arthropod-borne; vector; RNA virus; mycovirus; Chrysoviridae; sequencing; Serbia
Online: 15 July 2022 (11:44:59 CEST)
Mosquitoes are widespread arthropods that serve as vectors for a broad spectrum of viruses, many of which pose a substantial threat to humans. Conversely, some viruses may seemingly present with beneficial implications for the health of man whilst impinging on other domains of life, such as the fungi-infecting mycoviruses. This study is only the second one so far to describe the exceptionally scarcely identified Xanthi chryso-like virus (XCLV), member of the mycopathogenic Chrysoviridae family, in a new geographical area and a novel potential arthropod vector, the Culex pipiens mosquito. Interestingly, the XCLV was initially fortuitously detected by West Nile virus-specific primers directed at a conserved part of the NS5 gene, possibly indicative of a genetic resemblance and shared ancestry reflected in the NS5 evolutionary heritage. Detection and characterization of the virus and insect alike was done via PCR and Sanger sequencing. This investigation draws attention to our knowledge of viral pervasiveness – be it topographical or vectorial – and how humble it truly is. Additionally, we would propose that more attention be given to arthropod-borne viral pathogens that might prove advantageous to human health.
REVIEW | doi:10.20944/preprints202102.0596.v1
Subject: Life Sciences, Biochemistry Keywords: Climate change; Urban Heat Islands; Mosquito-borne Disease; Mitigation Strategies
Online: 26 February 2021 (08:27:16 CET)
Cities worldwide are facing ever-increasing pressure to develop mitigation strategies for all sectors to deal with the impacts of climate change. Cities are expected to house 70% of the world’s population by 2050 and developing related resilient health systems is a significant challenge. Because of their physical nature, cities’ surface temperatures are often substantially higher than that of the surrounding rural areas, generating the so-called Urban Heat Island (UHI) effect. Whilst considerable emphasis has been placed on strategies to mitigate against the UHI-associated negative health effects of heat and pollution, the World Health Organization estimates that one of the main consequences of global warming will be an increased burden of such vector-borne diseases. Many of the major mosquito-borne diseases are urban and thus the global population exposed to these pathogens will steadily increase. Mitigation strategies beneficial for one sector may, however, be detrimental for another. Implementation of inter-sectoral strategies that can benefit many sectors (such as water, labour and health) do exist and would enable optimal use of the meagre resources available. Discussion among inter-sectoral stakeholders should be actively encouraged.
ARTICLE | doi:10.20944/preprints202206.0210.v2
Subject: Biology, Other Keywords: Food safety; Fresh-cut produce; salads; Food borne pathogens; Microbiological safety
Online: 29 June 2022 (09:47:27 CEST)
The consumption and sale of fresh-cut products and salads have been growing tremendously in the present era. Therefore, the microbial safety of such products is of great concern. In the current study, a survey of general microbiological safety of fresh-cut produce and salads at quick-service restaurants (QSR) was undertaken across the Kingdom of Saudi Arabia. These findings were compared with microbiological criteria for foodstuffs by Saudi standards, metrology, and quality organization SASO-GSO-1016. Of the 82 samples of fresh-cut produce, 7% of samples were found to be unsatisfactory or beyond the acceptable limits. TPC count was unsatisfactory at 22%, coliform at 48%, and Staphylococcus aureus at 4%. For 108 samples for fresh salads, 11% of samples were found to be unsatisfactory or beyond the acceptable limits,13%, 27%, 4%, and 27% of samples showed an unsatisfactory range of TPC, coliforms, S. aureus, and Escherichia coli, respectively. The fresh-cut produce and salads were microbiologically safe in the central region compared to the eastern region followed by the western region. The relatively higher count was found in green pepper, mixed vegetables, and lettuce followed by fresh-cut onions and coleslaw salads. No Salmonella was detected in both fresh-cut produce and salads. The restaurants should be more stringent in their processing to ensure the consumer safety. Washing and sanitization of produce is the only way to reduce the diffusion of food borne pathogens.
ARTICLE | doi:10.20944/preprints201903.0234.v1
Subject: Biology, Animal Sciences & Zoology Keywords: Batrachochytrium dendrobatidis; Chytridiomycosis; Amphibian pathogen; Amphibian disease; Culex quinquefasciatus, vector-borne disease
Online: 26 March 2019 (10:01:02 CET)
The amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is an infectious disease responsible for the worldwide decline of amphibian species. To mitigate these declines, it is necessary to identify the various vectors by which the fungus can be transmitted between individuals and populations. The objective of this study was to determine whether adult female mosquitoes can carry and transfer Bd fungal cells. Mosquitoes were exposed to net soaked in a live Bd zoospore suspension to determine whether they are able to externally acquire the fungus. Another group was placed into containers with a sterile and Bd-inoculated agar plate to determine whether mosquitoes could transfer Bd between these surfaces. Bd DNA was found to be present on mosquito legs exposed to inoculated netting and agar plates suggesting that Bd can be transmitted by the mosquito over short distances This is the first study to demonstrate that an insect host may be a mechanical vector of Bd and suggests that we should begin to consider the role of mosquitoes in the dissemination and control of the fungus.
ARTICLE | doi:10.20944/preprints201901.0111.v1
Subject: Medicine & Pharmacology, Veterinary Medicine Keywords: Zoonoses, food-borne, disease control, public health, domestic livestock, pigs, One health
Online: 11 January 2019 (10:59:03 CET)
Non-typhoid salmonellosis is a common and problematic foodborne zoonotic disease in which pork and pork products can be an important potential source of infection. In order to prevent this disease important efforts to monitor the situation in the main source, livestock, are conducted in most developed countries. In the European Union EFSA and ECDC compile information at the member state level, even though important differences in production systems and surveillance systems exist. Here, Salmonella surveillance systems in one of the main sources of foodborne salmonellosis, swine, and humans in Spain were reviewed to identify potential gaps and discuss potential ways of integration under a One Health approach. Despite the extensive information generated through the surveillance activities source attribution can be only routinely performed through ad-hoc outbreak investigations, and national reports on human outbreaks do not provide sufficiently detailed information to gain a better understanding of the epidemiology of the pathogen. Human and animal monitoring of Salmonella would benefit from a better exchange of information and collaboration. Analysis of spatio-temporal trends in livestock and humans could help to identify likely sources of infection and to target surveillance efforts in areas with higher prevalence or where specific strains are found.
REVIEW | doi:10.20944/preprints202009.0103.v1
Subject: Medicine & Pharmacology, Other Keywords: climate change; vector-borne disease; artificial intelligence; explainable AI; geospatial modeling; infectious disease; arbovirus
Online: 4 September 2020 (12:21:32 CEST)
As recent history has shown, changing climate not only threatens to increase the spread of known disease, but also the emergence of new and dangerous phenotypes. This occurred most recently with West Nile virus: a virus previously known for mild febrile illness rapidly emerged to become a major cause of mortality and long-term disability throughout the world. As we move forward, into increasingly uncertain times, public health research must begin to incorporate a broader understanding of the determinants of disease emergence – what, how, why, and when. The increasing mainstream availability of high-quality open data and high-powered analytical methods presents promising new opportunities. Up to now, quantitative models of disease outbreak risk have been largely based on just a few key drivers, namely climate and large-scale climatic effects. Such limited assessments, however, often overlook key interacting processes and downstream determinants more likely to drive local manifestation of disease. Such pivotal determinants may include local host abundance, human behavioral variability, and population susceptibility dynamics. The results of such analyses can therefore be misleading in cases where necessary downstream requirements are not fulfilled. It is therefore important to develop models that include climate and higher-level climatic effects alongside the downstream non-climatic factors that ultimately determine individual disease manifestation. Today, few models attempt to comprehensively address such dynamics: up until very recently, the technology simply hasn’t been available. Herein, we present an updated overview of current perspectives on the varying drivers and levels of interactions that drive disease spread. We review the predominant analytical paradigms, discuss their strengths and weaknesses, and highlight promising new analytical solutions. Our focus is on the prediction of arboviruses, particularly West Nile virus, as these diseases represent the pinnacle of epidemiological complexity – solution to which would serve as an effective “gatekeeper”. We present the current state-of-the-art with respect to known drivers of arbovirus outbreak risk and severity, differentially highlighting the impact of climate and non-climatic drivers. The reality of multiple classes of drivers interacting at different geospatial and temporal scales requires advanced new methodologies. We therefore close out by presenting and discussing some promising new applications of AI. Given the reality of accelerating disease risks due to climate change, public health and other related fields must begin the process of updating their research programs to incorporate these much needed, new capabilities.
REVIEW | doi:10.20944/preprints202210.0052.v1
Subject: Biology, Animal Sciences & Zoology Keywords: animal-assisted interventions; child development; dog bites; dog-borne zoonoses; dog ownership; dog welfare; human-animal interactions
Online: 6 October 2022 (08:13:49 CEST)
Our wellbeing is greatly influenced by our childhood and adolescence, and the relationships that we form during those phases of our development. The human-dog bond started thousands of years ago. The higher prevalence of dog ownership around the world, especially in households including children along with the growing number of people studying dogs most likely explain the growing literature focusing on child-dog interactions. We review the potential effects of child-dog interactions on the physical, mental, and social wellbeing of both species. A scoping search of the SCOPUS database found several hundred documents meeting selection criteria. It allowed us to define the numerous ways in which children and dogs can interact, be it neutral (e.g., sharing a common area), positive (e.g., petting), or negative (e.g., biting). Then, we found evidence for an association between interacting with dogs during childhood and an array of health and mental benefits like stress relief and the development of empathy. Walking a dog and playing with one are perfect physical activity opportunities. Additionally, interacting with a dog can help lower stress and may have a role in the development of empathy. Nonetheless, a number of detrimental outcomes have also been identified in both humans and dogs. Children are the most at-risk population regarding dog bites and dog-borne zoonoses, which may lead to a subsequent fear of dogs or even death. Moreover, pet bereavement is generally inevitable when living with a canine companion and should not be trivialized. In terms of dogs, children sometimes take part in caretaking behaviors toward them which include going on walks. They are opportunities for dogs to relieve themselves outside, but also to exercise and socialize. In contrast, a lack of physical activity can lead to the onset of obesity. Dogs may present greater levels of stress when in the presence of children. Finally, the welfare of assistance, therapy, and free-roaming dogs remains underexplored. Overall, the study of the effects, positive as well as negative, on both species still requires further development. We call for more longitudinal studies and hope for cross-cultural research in the future in order to better understand the impact child-dog interactions might have.
ARTICLE | doi:10.20944/preprints202002.0114.v1
Subject: Biology, Other Keywords: Jingmen tick virus; Alongshan virus; flavi-like viruses; class II viral fusion proteins; O-liked glycans; mucin-like domain; virus evolution
Online: 9 February 2020 (17:29:14 CET)
Jingmen viruses are newly described segmented flavi-like viruses that have a worldwide distribution in ticks and have been associated with febrile illnesses in humans. Computational analyses were used to predict that Jingmen flavi-like virus glycoproteins have structural features of class II viral fusion proteins, including an ectodomain consisting of beta-sheets and short alpha-helices, a fusion peptide with interfacial hydrophobicity and a three domain architecture. Jingmen flavi-like virus glycoproteins have a sequence enriched in serine, threonine and proline at the amino terminus, which is a feature of mucin-like domains. Several of the serines and threonines are predicted be modified by the addition of O-linked glycans. Some of the glycoproteins are predicted to have an additional mucin-like domain located prior to the transmembrane anchor, whereas others are predicted to have a stem consisting of two alpha-helices. The flavivirus envelope protein and Jingmen flavi-virus glycoproteins may have diverged from a common class II precursor glycoprotein with a mucin-like domain or domains acquired after divergence.