A5023622396- Viral Infections and Vectors
- Viral Infections and Outbreaks Research
- Vector-Borne Animal Diseases
- Mosquito-borne diseases and control
- Fire effects on ecosystems
- Animal Disease Management and Epidemiology
- Hepatitis B Virus Studies
- Viral gastroenteritis research and epidemiology
- Disaster Response and Management
- Virology and Viral Diseases
- Rabies epidemiology and control
- Vector-borne infectious diseases
- Animal Virus Infections Studies
- Plant Virus Research Studies
- Poxvirus research and outbreaks
- Viral Infections and Immunology Research
- T-cell and Retrovirus Studies
- Yersinia bacterium, plague, ectoparasites research
- Zoonotic diseases and public health
- Bacillus and Francisella bacterial research
- Malaria Research and Control
- Hepatitis Viruses Studies and Epidemiology
- COVID-19 epidemiological studies
- Microbial infections and disease research
- Cytomegalovirus and herpesvirus research
University of Pretoria
2015-2025
Onderstepoort Veterinary Academic Hospital
2016-2025
Centers for Disease Control and Prevention
1996-2020
National Health Laboratory Service
2007-2017
National Institute for Communicable Diseases
2005-2016
Onderstepoort Veterinary Institute
2012-2016
Institute for Soil, Climate and Water
2016
Respiratory and Meningeal Pathogens Research Unit
2004-2014
National Center for Communicable Diseases
2003-2010
University of Aberdeen
1999-2009
Several human and animal Ebola outbreaks have occurred over the past 4 years in Gabon Republic of Congo. The consisted multiple simultaneous epidemics caused by different viral strains, each epidemic resulted from handling a distinct gorilla, chimpanzee, or duiker carcass. These populations declined markedly during outbreaks, apparently as result infection. Recovered carcasses were infected variety suggesting that great apes virus introductions natural host. Surveillance mortality may help...
In July and September 2007, miners working in Kitaka Cave, Uganda, were diagnosed with Marburg hemorrhagic fever. The likely source of infection the cave was Egyptian fruit bats (Rousettus aegyptiacus) based on detection virus RNA 31/611 (5.1%) bats, virus-specific antibody bat sera, isolation genetically diverse from tissues. isolates collected nine months apart, demonstrating long-term circulation. colony estimated to be over 100,000 animals using mark re-capture methods, predicting...
Lujo virus (LUJV), a new member of the family Arenaviridae and first hemorrhagic fever–associated arenavirus from Old World discovered in three decades, was isolated South Africa during an outbreak human disease characterized by nosocomial transmission unprecedented high case fatality rate 80% (4/5 cases). Unbiased pyrosequencing RNA extracts serum tissues victims enabled identification detailed phylogenetic characterization within 72 hours sample receipt. Full genome analyses LUJV showed it...
In May 1995, an international team characterized and contained outbreak of Ebola hemorrhagic fever (EHF) in Kikwit, Democratic Republic the Congo. Active surveillance was instituted using several methods, including house-to-house search, review hospital dispensary logs, interview health care personnel, retrospective contact tracing, direct follow-up suspect cases. field, a clinical case defined as signs, plus with case-patient, or at least 3 10 symptoms. A total 315 cases EHF, 81% fatality,...
Journal Article The Clinical Pathology of Crimean-Congo Hemorrhagic Fever Get access R. Swanepoel, Swanepoel Please address requests for reprints to Dr. Special Pathogens Unit, National Institute Virology, Sandringham 2131, Republic South Africa. Search other works by this author on: Oxford Academic PubMed Google Scholar D. E. Gill, Gill A. J. Shepherd, Shepherd P. Leman, Leman H. Mynhardt, Mynhardt S. Harvey Reviews Infectious Diseases, Volume 11, Issue Supplement_4, May-June 1989, Pages...
Marburg virus (family Filoviridae) causes sporadic outbreaks of severe hemorrhagic disease in sub-Saharan Africa. Bats have been implicated as likely natural reservoir hosts based most recently on an investigation cases among miners infected 2007 at the Kitaka mine, Uganda, which contained a large population virus-infected Rousettus aegyptiacus fruit bats. Described here is ecologic Python Cave, where American and Dutch tourist acquired infection December July 2008. More than 40,000 R. were...
Thirty-three varieties of 24 species plants and 19 vertebrates invertebrates were experimentally inoculated with Ebola Zaire virus. Fruit insectivorous bats supported replication circulation high titers virus without necessarily becoming ill; deaths occurred only among that had not adapted to the diet fed in laboratory.
Ebola hemorrhagic fever (EHF) patients treated at Kikwit General Hospital during the 1995 outbreak were tested for viral antigen, IgG and IgM antibody, infectious virus. Viral antigen could be detected in virtually all acute phase of illness, while antibody was not always detectable before death. Virus also isolated from course their febrile but attempts to quantify virus Vero E6 cells by standard plaque assay often unsuccessful. appeared approximately same time after disease onset (8–10...
In December 1997, 170 hemorrhagic fever-associated deaths were reported in Garissa District, Kenya. Laboratory testing identified evidence of acute Rift Valley fever virus (RVFV). Of the 171 persons enrolled a cross-sectional study, 31(18%) anti-RVFV immunoglobulin (Ig) M positive. An age-adjusted IgM antibody prevalence 14% was estimated for district. We estimate approximately 27,500 infections occurred making this largest recorded outbreak RVFV East Africa. multivariable analysis, contact...
The role of immune mechanisms in the pathogenesis Ebola hemorrhagic fever (EHF) remains to be elucidated. In this report, serum cytokine levels patients who died EHF were compared with those recovered and control patients. A marked elevation interferon (IFN)-gamma (>100 pg/mL) was observed sequential samples from all fatal cases or controls. Markedly elevated interleukin (IL)-2, IL-10, tumor necrosis factor (TNF)-alpha, IFN-alpha also noted cases; however, they had a greater degree...
Following the diagnosis in 1981 of first case Crimean-Congo hemorrhagic fever (CCHF) South Africa, an antibody survey was undertaken on cattle sera to determine distribution virus and specific diagnostic tests were routinely applied specimens from suspected cases establish medical significance its presence. Antibody CCHF demonstrated by reversed passive hemagglutination-inhibition technique 2,460/8,667 (28%) 140/180 herds tested as well 347/763 (45%) 32/34 (94%) Zimbabwe. The found all major...
To determine reservoir hosts for Marburg virus (MARV), we examined the fauna of a mine in northeastern Democratic Republic Congo. The was associated with protracted outbreak hemorrhagic fever during 1998-2000. We found MARV nucleic acid 12 bats, comprising 3.0%-3.6% 2 species insectivorous bat and 1 fruit bat. antibody to serum 9.7% 20.5% species, but attempts isolate were unsuccessful.
An outbreak of Marburg hemorrhagic fever was first observed in a gold-mining village northeastern Democratic Republic the Congo October 1998.We investigated most intensively May and 1999. Sporadic cases short chains human-to-human transmission continued to occur until September 2000. Suspected were identified on basis case definition; confirmed by detection virus antigen nucleic acid blood, cell culture, antibody responses, immunohistochemical analysis.A total 154 (48 laboratory-confirmed...
The first confirmed Rift Valley fever outbreak outside Africa was reported in September 2000, the Arabian Peninsula. As of February 2001, a total 884 hospitalized patients were identified Saudi Arabia, with 124 deaths. In Yemen, 1,087 cases estimated to have occurred, 121 Laboratory diagnosis virus (RVFV) infections included genetic detection and characterization clinical specimens by reverse transcription-polymerase chain reaction, addition serologic tests isolation. Genetic analysis...
Laboratory diagnosis of Ebola hemorrhagic fever (EHF) is currently performed by virus isolation and serology can be done only in a few high-containment laboratories worldwide. In 1995, during the EHF outbreak Democratic Republic Congo, possibility using immunohistochemistry (IHC) testing formalin-fixed postmortem skin specimens was investigated as an alternative diagnostic method for EHF. Fourteen 19 cases suspected met surveillance definition were positive IHC. IHC, serologic, results...
Abstract. In mid‐September 2000, Rift Valley fever (RVF) virus was diagnosed as the cause of infection in humans and livestock Jizan Region, Saudi Arabia. This is first time that this arbovirus has been found outside Africa Madagascar. Collections mosquitoes (Diptera: Culicidae) were therefore undertaken (from 25 September to 10 October) at eight sites during epidemic obtain for attempted RVF isolation. Among 23 699 mosquito females tested, isolations made from six 15 428 Culex ( )...
Historical outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns El Niño/Southern Oscillation (ENSO) phenomenon, which results in elevated and widespread rainfall over RVF endemic areas Africa. Using satellite measurements global regional sea surface temperatures, rainfall, derived-normalized difference vegetation index data, we predicted lead times 2-4 months where humans animals were expected occurred Horn Africa, Sudan, Southern Africa at...
Viruses in the Ebolavirus and Marburgvirus genera (family Filoviridae) have been associated with large outbreaks of hemorrhagic fever human nonhuman primates. The first documented cases occurred primates over 45 years ago, but amount virus genetic diversity detected within bat populations, which recently identified as potential reservoir hosts, suggests that filoviruses are much older. Here, detailed Bayesian coalescent phylogenetic analyses performed on 97 whole-genome sequences, 55 newly...
Abstract Phylogenetic relationships were examined for 198 Rift Valley fever virus isolates and 5 derived strains obtained from various sources in Saudi Arabia 16 countries Africa during a 67-year period (1944–2010). A maximum-likelihood tree prepared with sequence data 490-nt section of the Gn glycoprotein gene showed that 95 unique sequences sorted into 15 lineages. 2010 isolate patient South potentially exposed to co-infection live animal vaccine wild was reassortant. The potential...
A nosocomial outbreak of disease involving 5 patients, 4 whom died, occurred in South Africa during September-October 2008. The first patient had been transferred from Zambia to for medical management. Three cases involved secondary spread infection the patient, and 1 was a tertiary infection. novel arenavirus identified. source patient's remains undetermined.