Short communication: detection and molecular characterization of hepatitis E virus in domestic animals of São Tomé and Príncipe

Tropical Animal Health and Production - As in most of the African continent, the status of hepatitis E virus (HEV) infection in domestic animals in São Tomé and Príncipe, an...     

External contamination of broilers by Campylobacter spp. increases from the farm to the slaughterhouse

ABSTRACT

1. In this study, classical and molecular microbiological methods for detection and quantification of Campylobacter spp. were used to estimate their prevalence in faecal samples and skin swabs collected from 31 broiler flocks (20 farms) in Portugal, and measure the impact of transport-related factors on the expected rising excretion rates from the farm to the slaughterhouse.

2. Data on husbandry practices and transport conditions were gathered, including time in transit, distance travelled or ante-mortem plant-holding time.

3. A generalised linear mixed model was used to evaluate the significance of a potential post-transport rise in Campylobacter spp. counts and to assess risk determinants.

4. At least one flock tested positive for Campylobacter spp. in 80% of the sampled farms. At the slaughterhouse, Campylobacter spp. were detected in all faecal samples, C. jejuni being the most commonly isolated.

5. A post-transport rise of Campylobacter spp. counts from skin swabs was observed using classical microbiological methods (from a mean of 1.43 to 2.40 log₁₀ CFU/cm²) and molecular techniques (from a mean of 2.64 to 3.31 log₁₀ genome copies/cm²).

6. None of the husbandry practices or transport-related factors were found to be associated with Campylobacter spp. counts.

7. This study highlights the need for more research to better understand the multi-factorial nature of Campylobacter spp., a public health threat that was found to be highly prevalent in a sample of Portuguese poultry farms.     

Isolation of a new human retrovirus from West African patients with AIDS

The etiological agent of AIDS, LAV/HTLV-III, is common in Central Africa but is not endemic in other areas of that continent. A novel human retrovirus, distinct from LAV/HTLV-III, has now been isolated from two AIDS patients from West Africa. Partial characterization of this virus revealed that it has biological and morphological properties very similar to LAV but that it differs in some of its antigenic components. Although the core antigens may share some common epitopes, the West African AIDS retrovirus and LAV differ substantially in their envelope glycoproteins. The envelope antigen of the West African virus can be recognized by serum from a macaque with simian AIDS infected by the simian retrovirus termed STLV-IIImac, suggesting that the West African AIDS virus may be more closely related to this simian virus than to LAV. Hybridization experiments with LAV subgenomic probes further established that this new retrovirus, here referred to as LAV-II, is distantly related to LAV and distinct from STLV-IIImac.