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.

Crimean-Congo haemorrhagic fever virus (CCHFV) is the most geographically widespread tick-borne virus. However, African strains are poorly represented in sequence databases. In addition, almost all sequence data have been obtained from cases of human disease, while information regarding circulation of the virus in tick and animal reservoirs is severely lacking. Here, we characterise the complete coding region of a novel CCHFV strain, detected in African blue ticks (Rhipicephalus (Boophilus) decoloratus) feeding on cattle in an abattoir in Kampala, Uganda. These cattle originated from a farm in Mbarara, a major cattle-trading hub for much of Uganda. Phylogenetic analysis indicates that the newly sequenced strain belongs to the African genotype II clade, which predominantly contains the sequences of strains isolated from West Africa in the 1950’s and South Africa in the 1980’s. Whilst, the viral S (nucleoprotein) and L (RNA polymerase) genome segments shared >90% nucleotide similarity with previously reported genotype II strains, the glycoprotein-coding M segment shared only 80% nucleotide similarity with the next most closely related strains, which were from India and China. This segment also displayed a large number of non-synonymous mutations previously unreported in genotype II strains. Characterisation of this novel strain adds to our limited understanding of the natural diversity of CCHFV circulating in both ticks and in Africa. Such data can be used to inform the design of vaccines and diagnostics, as well as studies exploring the epidemiology and evolution of the virus for the establishment of future CCHFV control strategies.

In this study, a case of acute cattle death was investigated. The pathogen was identified, and its molecular characteristics and vector were analysed. This study provides a reference for the prevention and control of babesiosis and the healthy breeding of cattle. In this study, unengorged and engorged Rhipicephalus microplus ticks were collected from the Chongqing area. The unengorged ticks were cultured on cattle under laboratory conditions, and the engorged ticks were cultured to lay eggs. In the process, the cattle suddenly died at 12 days from the bite of an unengorged R. microplus tick. In addition, the larvae hatched from R. microplus eggs, which were cultured on the other cattle, and the experimental cattle died in approximately 14 days. Blood was collected from a second dying and stored at 4 ℃ for one week. Two millilitres of anticoagulated blood was injected subcutaneously into the third cow without piriformis infection. On the fourth day, the body temperature rose to 41 ℃ with slight lymphadenopathy. On the fifth day, the cow suddenly fell and died approximately 4 hours later. DNA was extracted from the blood of all dead cattle and amplified by PCR with piriformis universal primers. The results showed that the cattle were infected with Babesia bovis. The phylogenetic tree based on 18S rRNA showed that the Chongqing strain of B. bovis, which caused the death of cattle, was closely related to the Yunnan strain in China and had the same taxonomic status as the Spanish strain. This case report will draw people's attention to B. bovis once again, and positive control measures should be taken to reduce the losses of farmers to achieve the goal of healthy breeding.

Abstract: Canine ehrlichiosis is a zoonotic disease transmitted by ticks, posing a formidable challenge to both veterinary and public health sectors worldwide. Across continents and regions, the prevalence rates of Ehrlichia canis exhibit significant variation, underlining the necessity for a nuanced and globally informed approach to understanding and combating this disease. The review navigates through this complexity, shedding light on the intricate pathogenesis of the illness. Central to this understanding is the bacterium's adept manipulation of the host's immune response, contributing to the diverse clinical manifestations observed in infected animals. Diagnostic methodologies, crucial for timely intervention and management, are subjected to critical assessment. From traditional microscopy to modern molecular techniques and serology, each approach is scrutinized for its strengths and limitations. By acknowledging these nuances, the review aims to equip practitioners with the knowledge necessary to make informed diagnostic decisions. A central tenet of this review is the advocacy for an integrated "One Health" approach. By leveraging advancements in genomics, proteomics, and artificial intelligence, there is a potential to enhance diagnostic accuracy and develop innovative therapeutic and preventive strategies globally. This collaborative approach recognizes the interconnectedness of human, animal, and environmental health, offering a holistic framework for tackling complex zoonotic diseases like canine ehrlichiosis. In conclusion, this review serves as a beacon of knowledge, illuminating the multifaceted landscape of canine ehrlichiosis. Through its synthesis of scientific literature and emphasis on methodological rigor, it provides a foundation upon which future research and interventions can be built. With a unified commitment to "One Health" principles and the integration of cutting-edge technologies, there exists the potential to mitigate the impact of this disease and safeguard both animal and human well-being worldwide

Chemical acaricides are widely used to control ticks and tick borne pathogens on cattle. However, prolonged and indiscriminate use of these chemicals inevitably leads to selection of resistant ticks. In-vitro bioassays (adult and larval immersion tests) were conducted to assess amitraz and del-tamethrin resistance in Rhipicephalus (Boophilus) microplus populations from communal farms of the King Sabata Dalindyebo municipality of South Africa. Data generated on percentage inhibi-tion of oviposition (% IO) revealed that all the tick populations assessed showed resistance (% IO≤ 95%) to at least one of the acaricides. All six tick populations assessed for efficacy (% IO≥ 95% at the DD) with deltamethrin were resistant (% IO≤ 95%) and only one of six tick populations as-sessed for efficacy with amitraz was susceptible. Based on resistance ratios, the adult immersion test detected amitraz and deltamethrin resistance in three and five of the six tick populations re-spectively. With the larval immersion test, deltamethrin and amitraz resistance (Larval mortality < 90 % at the DD) was detected in all four, and three of four R. (B.) microplus populations assessed respectively. This data is critical for the design of an effective and sustainable tick control strategy on the communal farms.