Laboratory diagnosis of Ebola hemorrhagic fever during an outbreak in Yambio, Sudan, 2004.

Between the months of April and June 2004, an Ebola hemorrhagic fever (EHF) outbreak was reported in Yambio county, southern Sudan. Blood samples were collected from a total of 36 patients with suspected EHF and were tested by enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G and M antibodies, antigen ELISA, and reverse-transcription polymerase chain reaction (PCR) of a segment of the Ebolavirus (EBOV) polymerase gene. A total of 13 patients were confirmed to be infected with EBOV. In addition, 4 fatal cases were classified as probable cases, because no samples were collected. Another 12 patients were confirmed to have acute measles infection during the same period that EBOV was circulating. Genetic analysis of PCR-positive samples indicated that the virus was similar to but distinct from Sudan EBOV Maleo 1979. In response, case management, social mobilization, and follow-up of contacts were set up as means of surveillance. The outbreak was declared to be over on 7 August 2004.

Yellow fever outbreak, Imatong, southern Sudan.

In May 2003, the World Health Organization received reports about a possible outbreak of a hemorrhagic disease of unknown cause in the Imatong Mountains of southern Sudan. Laboratory investigations were conducted on 28 serum samples collected from patients in the Imatong region. Serum samples from 13 patients were positive for immunoglobulin M antibody to flavivirus, and serum samples from 5 patients were positive by reverse transcription-polymerase chain reaction with both the genus Flavivirus-reactive primers and yellow fever virus-specific primers. Nucleotide sequencing of the amplicons obtained with the genus Flavivirus oligonucleotide primers confirmed yellow fever virus as the etiologic agent. Isolation attempts in newborn mice and Vero cells from the samples yielded virus isolates from five patients. Rapid and accurate laboratory diagnosis enabled an interagency emergency task force to initiate a targeted vaccination campaign to control the outbreak.

The use of short-course zidovudine to prevent perinatal transmission of human immunodeficiency virus in rural Kenya.

To determine the feasibility of using short-course zidovudine (ZDV) to prevent mother-to-child transmission of human immunodeficiency virus (HIV) in a breastfeeding population in a rural area in Kenya, pregnant mothers attending clinics in seven health centers in western Kenya between 1996 and 1998 were requested to volunteer for participation in this study. The HIV-infected mothers were given a daily dose of 400 mg of ZDV starting at 36 weeks of gestation and another 300 mg every three hours intrapartum. After delivery, mothers and their children were followed-up and clinically monitored every 3-4 months for two years, and child and mother mortality rates were analyzed. Of the 825 mothers who consented, 216 (26.2%) were infected with HIV. Of those infected, 51 (23.6%) took the full prescribed dose, 69 (31.9%) took only the prenatal dose, and the remaining 96 (44.4%) did not take any dose. Failure to take ZDV was attributed mainly to delivery occurring earlier than expected, while non-compliance to the intrapartum dose was due to mothers giving birth at home and fear of traditional birth attendants. By the end of the second year, 75 HIV-exposed children (34.7%) and 33 HIV-infected mothers (15.3%) had died. The HIV-free survival of children at 24 months was significantly associated with mother survival (P < 0.001) and prenatal ZDV compliance (P < 0.003). Our findings suggest that implementation of programs for prevention of mother-to-child transmission of HIV in rural areas of Africa need to consider the various socioeconomic and cultural barriers that may prevent successful uptake of antiretroviral prophylaxes. Similarly, the rapid disease progression in mothers may eliminate the increase in child survival due to ZDV prophylaxis.

Evaluation of the HIV-1 reverse transcriptase inhibitory properties of extracts from some medicinal plants in Kenya.

Extracts from twenty two medicinal plants popularly used in preparing traditional remedies in Kenya were screened for activity against the HIV-1 reverse transcriptase. The screening procedure involved the use of tritium labeled thymidine triphosphate as the enzyme substrate and polyadenylic acid.oligodeoxythymidylic acid [poly(rA).p(dT)12-18] as the template primer dimer. Foscarnet was used as a positive control in these experiments. At a concentration of 100 microg/ml, extracts from eight of these plants showed at least 50 per cent reverse transcriptase inhibition. This activity was arbitrarily considered as significant. This indicates that there is the probability that some antiretroviral compounds could be identified and isolated from materials from these plants.

Prevalence of hepatocellular carcinoma, liver cirhosis and HBV carriers in liver disease patients referred to Clinical Research Centre, Kemri.

The prevalence of HBsAg positivity, liver cirrhosis (LC) and hepatocellular carcinoma (HCC) is studied in 139 patients at the Clinical Research Centre of KEMRI. The prevalences were found to be 15.1%, 9.3 % and 10 % respectively. 14% of the HBsAg positives were also E antigen positive. The positivity of HBsAg in HCC was 42.9% only 15.4% in LC and 57.1% HCC had AFP compared to only 15.4% in LC. It is suggested that the findings support an association of Hepatitis B virus with LC and HCC.

Serological studies and ultrasonographic diagnosis of chronic liver disease in Kenya.

Blood samples were obtained from blood donors and patients with chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC) from provincial hospitals and Kenyatta National Hospital (KNH). Patients with chronic liver disease (CH, LC and HCC) underwent abdominal ultrasound screening as well. The blood samples were screened for Hepatitis B surface antigen (HBsAg), anti hepatitis C virus (Hep CV) antibodies and alpha fetoprotein (AFP). A total of 44665 blood samples from blood donors were screened for HBsAg between July 1991 and January 1993. Of these 4.1% were found to be HBsAg positive. A total of 983 samples were taken from chronic liver disease patients out of which 22.2% were found to be HBsAg positive. Sixty-three patients were found to have liver cirrhosis and 53 patients had HCC on ultrasound screening. Anti Hep CV antibodies were found in 4.3% (5/116) of patients with LC and HCC. AFP levels were found to be significantly higher in HCC patients than in LC patients, levels of above 200 ng/ml being diagnostic of HCC. Follow up of high risk patients, i.e. those with HBsAg positive, chronic liver disease, by ultrasound screening and AFP detection may be useful in the early detection of HCC.