ARTICLE | doi:10.20944/preprints202212.0515.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Mansonella perstans; onchocerciasis; nodding syndrome; epilepsy; Tanzania
Online: 27 December 2022 (09:20:31 CET)
In South Sudan, three case-control studies found a positive association between Nodding Syn-drome (NS) and a Mansonella perstans infection. To investigate whether M. perstans could play the primary and sole causal role in the development of NS, we examined blood films of persons with and without epilepsy in rural villages affected by NS in Mahenge, Tanzania, to identify M. perstans infections. Study participants were also examined for onchocercal nodules and skin lesions and tested for the presence of anti-O. volvulus antibodies (Ov16 ELISA). One hundred and thirteen epilepsy cases and 132 controls were enrolled, with a mean age of 28.3 years (interquartile range 22 – 34 years); 125 (51%) were females. Of the persons with epilepsy, 43 (38.1%) met the probable NS criteria. M. perstans infection was absent in all participants, but Ov16 prevalence and oncho-cerciasis-associated skin manifestations were positively associated with epilepsy, including probable NS. Onchocercal nodules in the mothers of cases were also positively associated with epilepsy. In conclusion, in contrast with O. volvulus, M. perstans is likely not endemic in Mahenge and therefore cannot be a co-factor for NS in the area. Hence, this filaria cannot be the primary and sole causal factor in the development of NS.
ARTICLE | doi:10.20944/preprints202103.0646.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: WHO-5 Well-being; COVID-19; social distancing; preventive measures; Vietnam
Online: 25 March 2021 (16:35:46 CET)
The COVID-19 pandemic and associated restrictive measures implemented may considerably affect people’s lives. This study aimed to assess the well-being of Vietnamese people after COVID-19 lockdown measures were lifted and life gradually returned to normal. An online survey was organized from 21st to 25th April 2020 among Vietnamese residents aged 18 and over. Besides collecting socio-demographic and COVID-19-related data, the WHO-5 Well-Being Index (scored 0–25) was used to score participants’ well-being. A multivariate logistic regression model was used to determine the predictors of well-being. A total of 1922 responses were analyzed (mean age: 31 years; 30.5% male). Mean well-being score was 17.35±4.97. Determinants of high well-being score (≥13) included older age, eating healthy food, practising physical exercise, working from home, and adhering to the COVID-19 preventive measures. Female participants, persons worried about their relatives’ health, and smokers were more likely to have a low well-being score. In conclusion, after the lockdown measures were lifted, the Vietnamese people continued to follow COVID-19 preventive measures and most of them scored high on the well-being scale. Waiting to achieve large scale COVID-19 vaccine coverage, promoting preventive COVID-19 measures remains important, together with strategies to guarantee the well-being of the Vietnamese people.
ARTICLE | doi:10.20944/preprints202104.0135.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Onchocerciasis; Onchocerca volvulus; epilepsy; nodding syndrome; prevalence; ivermectin
Online: 5 April 2021 (12:53:07 CEST)
In June 2020, a door-to-door household survey was conducted in Mvolo County, an onchocerciasis endemic area in South Sudan. A total of 2,357 households containing 15,699 individuals agreed to participate in the study. Of these, 5,046 (32.1%, 95%CI: 31.4-32.9%) had skin itching and 445 (2.8%, 95% CI: 2.6-3.1%) were blind. An epilepsy screening questionnaire identified 813 (5.1%) persons suspected to have epilepsy. Of them, 804 (98.9%) were seen by a medical doctor and in 798 (98.1%) the diagnosis of epilepsy was confirmed. The overall epilepsy prevalence was 50.8/1000 (95% CI: 47.6-54.4/1000) and prevalence of nodding syndrome was 22.4/1000 (95% CI: 20.1-24.9/1000). Younger age, being male, skin itching, blindness and living in a village close to the Naam river were risk factors for epilepsy. The annual incidence of epilepsy was 82.8/100,000 (95% CI: 44.1-141.6/100,000). In conclusion, a high prevalence and incidence of epilepsy was observed in Mvolo, South Sudan. Strengthening the onchocerciasis elimination programme is urgently needed to prevent epilepsy in this region.
ARTICLE | doi:10.20944/preprints202207.0366.v1
Subject: Medicine And Pharmacology, Tropical Medicine Keywords: onchocerciasis; community directed treatment with ivermectin; elimination; epilepsy; focus group discussions; misconceptions
Online: 25 July 2022 (09:27:22 CEST)
Despite of over 20 years of community directed treatment with ivermectin (CDTI), a high prevalence of onchocerciasis and onchocerciasis-associated epilepsy were observed in rural villages in Mahenge, Tanzania. Therefore, we assessed the knowledge, attitude and practice about onchocerciasis in four rural villages in the Mahenge area. This was a qualitative study conducted between June and July 2019. Eleven focus group discussions were organized with persons with epilepsy and their caretakers, community resource persons, and community drug distributors (CDDs), and two in-depth interviews with district programme coordinators of neglected tropical diseases (NTD). Most participants were aware about symptoms of onchocerciasis using local terminologies such as “ukurutu/rough dry skin” and “kuwashwa/itching”. A small proportion of people did not take ivermectin during CDTI for fear of adverse reactions such as itching and swelling. Some men believed that ivermectin may decrease libido. Challenges for high CDTI coverage included, long walking distance by CDDs to deliver drugs to households, persons being away for farming, low awareness of the disease and limited supervision by the NTD coordinators. In conclusion, ivermectin uptake in Mahenge should be optimised by continuous advocacy about the importance of taking ivermectin to prevent onchocerciasis-associated morbidity and by improving supervision during CDTI.
ARTICLE | doi:10.20944/preprints202202.0270.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Onchocerciasis; Onchocerca volvulus; epilepsy; nodding syndrome; ivermectin
Online: 22 February 2022 (11:10:26 CET)
A two phase survey of epilepsy was conducted in selected villages in Mundri West and East Counties (26 June−8 July, 2021), an onchocerciasis-endemic area in Western Equatoria State in South Sudan. In the first phase, households were visited by a trained research team to identify persons suspected to have epilepsy. In the second phase, persons suspected to have epilepsy were interviewed and examined by a clinician to confirm the diagnosis. A total of 364 households agreed to participate in the survey, amounting to 2,588 individuals. The epilepsy screening questionnaire identified 91 (3.5%) persons suspected to have epilepsy, of whom in 86 (94.5%) the diagnosis of epilepsy was confirmed by a clinician. The overall prevalence of confirmed epilepsy was 3.3% (95% CI: 2.7-4.1%), and of nodding syndrome 0.9% (95% CI: 0.6-1.4%). In 61 (16.8%) households there was at least one person with epilepsy. Only 1,212 (46.9%) of 2,583 people took ivermectin during the last distribution round in 2021. The annual epilepsy incidence was 77.3/100.000 (95% CI: 9.4-278.9/100,000) and the annual epilepsy mortality 251.2/100,000 (95% CI: 133.8-428.7/100,000). In conclusion, a high prevalence and incidence of epilepsy was observed in villages in Mundri. Urgent action is needed to prevent children from developing onchocerciasis-associated epilepsy by strengthening the local onchocerciasis elimination programme.
ARTICLE | doi:10.20944/preprints202001.0259.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: onchocerciasis; epielpsy; ivermectin; trial; seizures
Online: 22 January 2020 (09:40:45 CET)
Background There is anecdotal evidence that ivermectin may decrease the frequency of seizures in Onchocerca volvulus-infected persons with epilepsy (PWE). Methods In October 2017, a 12-month clinical trial was initiated in rural Democratic Republic of Congo. PWE with onchocerciasis-associated epilepsy with ≥2 seizures/month were randomly allocated to receive over a one year period, ivermectin once or thrice (group 1), while other onchocerciasis-infected PWE (OIPWE) were randomized to ivermectin twice or thrice (group 2). All participants also received anti-epileptic drugs (AED). Study outcomes included seizure freedom during the last four months (primary endpoint), decrease in microfilarial density, and occurrence of adverse events. A multiple logistic regression model was used to evaluate the primary outcome. Results Of the 197 OIPWE enrolled, 100 were randomized to receive ivermectin thrice, 52 twice, and 45 once. In an intent-to-treat combined analysis of data from group 1 and 2, the probability to become seizure-free for OIPWE treated with ivermectin twice per year was significantly higher than in those treated once (OR: 5.087, 95% CI: 1.378-19.749; p=0.018) and individuals who received ivermectin twice had a 4.471 (95% CI: 0.944-6.769, p=0.075) times higher odds of seizure freedom than those received ivermectin once per year. Absence of microfilariae during the last 4 months was associated with a higher probability of seizure freedom (p=0.027). Conclusions Increasing the number of ivermectin treatments per year was found to suppress both microfilarial density and seizure frequency in OIPWE, suggesting that O. volvulus infection plays an etiological role in causing seizures. Registration: www.clinicaltrials.gov; NCT03852303