Use of Brucella abortus species specific polymerase chain reaction assay for the diagnosis of bovine brucellosis.

Serology is primarily used in the diagnosis of bovine brucellosis. Bacterial culture and isolation is the gold standard in diagnosing brucellosis but, like serology, it does not offer complete (100%) diagnostic sensitivity and specificity. Polymerase chain reaction (PCR) has been suggested to offer better specificity and sensitivity. In this study, we evaluated the performance of Brucella abortus species specific (BaSS) PCR directly from different samples in the diagnosis of bovine brucellosis in naturally infected cattle in KwaZulu-Natal province of South Africa with known infectious status from culture. The BaSS PCR had a low diagnostic sensitivity (DSe) of 70%, but was able to identify vaccine strains using abomasal fluid from aborted foetuses and detect Brucella DNA from decomposing samples. The best sample for the BaSS PCR was abomasal fluid.

An evaluation of serological tests in the diagnosis of bovine brucellosis in naturally infected cattle in KwaZulu-Natal province in South Africa.

The diagnostic sensitivity (DSe) of the Rose Bengal test (RBT), the complement fixation test (CFT), the serum agglutination test (SAT), the competitive enzyme-linked immunosorbent assay (cELISA) and the indirect ELISA (iELISA) were determined in naturally infected cattle in KwaZulu-Natal province of South Africa with known infectious status from culture (gold standard). Natural brucellosis infection status of animals was determined by culturing and identification of Brucella abortus biovar 1 from abomasal fluid, milk, hygroma fluid, lymph nodes or uterine discharges samples. The diagnostic specificity (DSp) of the tests mentioned above was determined using samples from known negative herds. There was no statistically significant difference between the tests in their ability to diagnose brucellosis. The RBT and iELISA had the highest DSe of 95.8%, whereas RBT and CFT had the highest DSp of 100%. In South African laboratories, the RBT and CFT serological tests are used, because of the cost efficacy of CFT when compared to the less labour intensive but more expensive iELISA.

The prevalence and distribution of non-communicable diseases and their risk factors in Kasese district, Uganda.

BACKGROUND: To date there has been no population-based survey of the major risk factors for non-communicable diseases (NCD) in Uganda. Hospital-based data from urban centres report an increasing burden of NCDs in Uganda. This population-based survey aimed to describe the prevalence of risk factors for NCDs in a rural Ugandan district. METHODS: The survey was conducted using the WHO STEPwise approach to surveillance of non-communicable diseases (STEPS) methodology. Participants (n = 611) were residents of the Kasese district selected in a one-step, complete survey of a rural district. Standardised international protocols were used to record history of disease, and measure behavioural risk factors (smoking, alcohol consumption, fruit and vegetable consumption, physical activity), physical characteristics [weight, height, waist and hip circumferences, blood pressure (BP)], fasting blood glucose (BG) and total cholesterol (TC) levels. Data were analysed using simple descriptive analysis. RESULTS: In this sample, the prevalence of hypertension (systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg) was 22.1% for men and 20.5% for women. Fifteen per cent of men and 16.8% of women were overweight [body mass index (BMI) ≥ 25 kg/m(2)] and 4.9% of men and 9.0% of women were obese (BMI ≥ 30 kg/m(2)). Nine per cent of participants were diabetic, 7.2% ate five or more combined servings of fruit per day while only 1.2% ate five or more combined servings of vegetables per day. Fifty-one per cent of the population were physically inactive and 9.6% were daily smokers. Thirty-one per cent of females had fasting blood sugar levels (FBS) ≥ 6.1 mmol/l while 10% of males had FBS > 6.1 mmol/l. CONCLUSION: This study presents evidence on the magnitude of NCDs, their risk factors and gender distribution in a rural population in Uganda, a poor country in east-central Africa. These data, when combined with urban population data, could be useful in the formulation and advocacy of NCD policy and plans of action in Uganda.

Characterisation of a highly pathogenic influenza A virus of subtype H5N2 isolated from ostriches in South Africa in 2004.

OBJECTIVES: The HPAI H5N2 strain that caused an outbreak in ostriches of the Eastern Cape Province, South Africa in 2004 was characterized. DESIGN: Haemagglutination inhibition (HI) and agar gel immunodiffusion (AGID) were performed on sera from ostrich farms in the outbreak region, and intravenous pathogenicity (IVPI) tests, reverse-transcriptase-polymerase-chain reaction (RT-PCR), nucleic acid sequencing and phylogenetic comparisons were performed on the HPAI H5N2 virus isolated during the outbreak. RESULTS: The deduced amino acid sequence at the HA0 cleavage site determined by RT-PCR and nucleotide sequencing was PQREKRRKKRGLF and thus the virus fell within the definition of a highly pathogenic virus, but in an IVPI test in chickens on the virus isolated from the index case and a value of 0.63 was recorded, which is below the criterion for highly pathogenic viruses in this in vivo test. After a further passage in embryonated eggs a second IVPI was carried out and an elevated value of 1.19 was obtained. Cloacal swabs were taken from the initial IVPI birds, inoculated into embryonated chickens eggs and a third IVPI was then performed on the resulting haemagglutinating, infective allantoic fluid. An index of 2.73 was recorded. CONCLUSIONS: HI tests appeared to be the more sensitive test compared to AGID when testing for antibodies to avian influenza in sera. An ostrich-derived virus with a virulent HA0 cleavage site was not initially virulent in chickens but after passage in the latter the virulence increased. Phylogenetic analyses demonstrated the link between AI viruses carried by wild ducks and those infecting ostriches.