33 research outputs found
Antigenic characterisation of lyssaviruses in South Africa
There are at least six Lyssavirus species that have been isolated in Africa, which include classical rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus. In this retrospective study, an analysis of the antigenic reactivity patterns of lyssaviruses in South Africa against a panel of 15 anti-nucleoprotein monoclonal antibodies was undertaken. A total of 624 brain specimens, collected between 2005 and 2009, confirmed as containing lyssavirus antigen by direct fluorescent antibody test, were subjected to antigenic differentiation. The lyssaviruses were differentiated into two species, namely rabies virus (99.5%) and Mokola virus (0.5%). Furthermore, rabies virus was further delineated into two common rabies biotypes in South Africa: canid and mongoose. Initially, it was found that the canid rabies biotype had two reactivity patterns; differential staining was observed with just one monoclonal antibody. This difference was likely to have been an artefact related to sample quality, as passage in cell culture restored staining. Mongoose rabies viruses were more heterogeneous, with seven antigenic reactivity patterns detected. Although Mokola viruses were identified in this study, prevalence and reservoir host species are yet to be established. These data demonstrate the usefulness of monoclonal antibody typing panels in lyssavirus surveillance with reference to emergence of new species or spread of rabies biotypes to new geographic zones
Lagos Bat Virus, South Africa
Three more isolates of Lagos bat virus were recently recovered from fruit bats in South Africa after an apparent absence of this virus for 13 years. The sporadic occurrence of cases is likely due to inadequate surveillance programs for lyssavirus infections among bat populations in Africa
Movements of Two Rabid Raccoons, Procyon lotor, in Eastern Ontario
An adult female Raccoon Procyon lotor was captured about 3 km north of Mallorytown, Ontario, on 27 August 2004, as part of a government rabies control program. The animal was vaccinated against rabies, ear-tagged and released, and recaptured the next day 1.7 km south of the initial capture location. Upon recapture, the Raccoon had porcupine quills in its facial area and seemed agitated and was submitted for rabies testing. It was confirmed as rabies positive on 31 August 2004, by the Canadian Food Inspection Agency. Similarly, a juvenile male raccoon was captured, ear-tagged, vaccinated, and released near Junetown, Ontario (about 4 km NW of the other rabid Raccoon) on 5 September 2004. It was found dying in a residential window well on 22 September 2004, 700 meters from the original capture location. It was diagnosed as rabid on 23 September 2004
Absence of hepatitis delta infection in a large rural HIV cohort in Tanzania
OBJECTIVES: The epidemiological and clinical determinants of
hepatitis delta virus (HDV) infection in Sub-Saharan Africa are
ill-defined. The prevalence of HDV infection was determined in
HIV/hepatitis B virus (HBV) co-infected individuals in rural
Tanzania. METHODS: All hepatitis B virus (HBV)-infected adults
under active follow-up in the Kilombero and Ulanga
Antiretroviral Cohort (KIULARCO) were screened for anti-HDV
antibodies. For positive samples, a second serological test and
nucleic acid amplification were performed. Demographic and
clinical characteristics at initiation of antiretroviral therapy
(ART) were compared between anti-HDV-negative and positive
patients. RESULTS: Among 222 HIV/HBV co-infected patients on
ART, 219 (98.6%) had a stored serum sample available and were
included in the study. Median age was 37 years, 55% were female,
46% had World Health Organization stage III/IV HIV disease, and
the median CD4 count was 179 cells/mul. The prevalence of
anti-HDV positivity was 5.0% (95% confidence interval 2.8-8.9%).
There was no significant predictor of anti-HDV positivity. HDV
could not be amplified in any of the anti-HDV-positive patients
and the second serological test was negative in all of them.
CONCLUSIONS: No confirmed case of HDV infection was found among
over 200 HIV/HBV co-infected patients in Tanzania. As
false-positive serology results are common, screening results
should be confirmed with a second test
Prevalence and Outcomes of Hepatitis B Co-infection and Associated Liver Disease Among Antiretroviral Therapy-Naive Individuals in a Rural Tanzanian Human Immunodeficiency Virus Cohort
Background. We evaluated the prevalence of chronic hepatitis B virus (HBV) infection and liver fibrosis/cirrhosis in human immunodeficiency virus (HIV)-infected individuals enrolled in a rural Tanzanian prospective cohort and assessed hepatic fibrosis progression 12–24 months after antiretroviral treatment (ART) initiation. Methods. All ART-naive HIV-infected adults ≥15-year-old enrolled in the Kilombero and Ulanga Antiretroviral Cohort who started ART between 2005 and 2015 were included. Pre-ART factors associated with significant liver fibrosis (aspartate aminotransferase-to-platelet ratio index [APRI] >1.5) and cirrhosis (APRI > 2.0) were identified using logistic regression.
Results. Of 3097 individuals screened, 227 (7.3%; 95% CI, 6.4–8.2) were hepatitis B surface antigen (HBsAg) positive. Before ART initiation, 9.1% individuals had significant liver fibrosis and 5.3% had cirrhosis. Human immunodeficiency virus/HBVcoinfected individuals were more likely to have an APRI score indicating significant fibrosis (14.2% vs 8.7%, P = .03) and cirrhosis (9.2% vs 4.9%, P = .03) than HBV-uninfected patients. CD4 cell count <200 cell/μL and alcohol consumption were independently
associated with pre-ART APRI score, indicating significant fibrosis and cirrhosis in multivariable analyses. Among individuals with elevated APRI measurements pre- and 12–24 months post-ART initiation, 53 of 57 (93.0%) of HIV-monoinfected and 4 of 5 (80.0%) of HIV/HBV-coinfected had a regression to APRI < 1.5. Conclusions. Hepatic fibrosis and cirrhosis were common in our cohort, especially among HIV/HBV-coinfected individuals. The APRI improved in most patients. Pre-ART HBsAg screening and early onset of tenofovir-based ART for HIV/HBV-coinfection should be prioritized in sub-Saharan Africa
Fatal Human Rabies due to Duvenhage Virus from a Bat in Kenya: Failure of Treatment with Coma-Induction, Ketamine, and Antiviral Drugs
The Role of DNA Barcodes in Understanding and Conservation of Mammal Diversity in Southeast Asia
Southeast Asia is recognized as a region of very high biodiversity, much of which is currently at risk due to habitat loss and other threats. However, many aspects of this diversity, even for relatively well-known groups such as mammals, are poorly known, limiting ability to develop conservation plans. This study examines the value of DNA barcodes, sequences of the mitochondrial COI gene, to enhance understanding of mammalian diversity in the region and hence to aid conservation planning.DNA barcodes were obtained from nearly 1900 specimens representing 165 recognized species of bats. All morphologically or acoustically distinct species, based on classical taxonomy, could be discriminated with DNA barcodes except four closely allied species pairs. Many currently recognized species contained multiple barcode lineages, often with deep divergence suggesting unrecognized species. In addition, most widespread species showed substantial genetic differentiation across their distributions. Our results suggest that mammal species richness within the region may be underestimated by at least 50%, and there are higher levels of endemism and greater intra-specific population structure than previously recognized.DNA barcodes can aid conservation and research by assisting field workers in identifying species, by helping taxonomists determine species groups needing more detailed analysis, and by facilitating the recognition of the appropriate units and scales for conservation planning