RESUMO
Viruses circulating in Ethiopia during the 1990s cluster with main subtype C, but a significant subcluster, C', was noted in multiple analyses. This subcluster of subtype C(C') was in a fifty-fifty equilibrium with the main subtype C (Abebe et al., AIDS Res Hum Retroviruses 2000;16:1909-1914). To analyze genetic diversification within the subcluster of HIV-1 subtype C designated C' in the course of the epidemic in Ethiopia, we analyzed 165 env gp120 V3 sequences obtained between 1988 and 1999. We observed a highly significant positive correlation between sampling years of individual sequences and their synonymous distances to the reconstructed common ancestor of the HIV-1 subtype C' subcluster. The extrapolation of the regression line of synonymous distances back to the date when no synonymous heterogeneity was present among the Ethiopian HIV-1 C' population allowed us to estimate 1982 (95% CI, 1980-1983) as the year of the onset of HIV-1 C' genetic diversification and expansion in Ethiopia. These results are in agreement with retrospective epidemiological and serological data, which demonstrated the absence of an HIV-1 epidemic in the Ethiopian population before the 1980s.
Assuntos
Infecções por HIV/epidemiologia , HIV-1/classificação , HIV-1/genética , Sequência de Aminoácidos , Sequência Consenso , Etiópia/epidemiologia , Variação Genética , Proteína gp120 do Envelope de HIV/química , Infecções por HIV/virologia , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Alinhamento de Sequência , Fatores de TempoRESUMO
Others and we have previously shown that subtype C is the predominant HIV-1 subtype and the major cause of AIDS in Ethiopia. The present study shows that subtype C in Ethiopia has a genetic subcluster, designated C', has not increased in frequency, or spread geographically, over the period 1988 (%C' = 23/53) to 1996-1997 (%C' = 26/50). There is no association of the HIV-1 subtype C or subcluster C' with geographic location, time of sample collection, or risk group in Ethiopia. Of 105 randomly collected samples representing 7 different towns in Ethiopia, all but 2 (1 subtype A from Addis Ababa, 1997 and 1 subtype D from Dessie, 1996) belong to subtype C.
Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Sequência de Aminoácidos , Etiópia/epidemiologia , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Filogenia , Análise de Sequência de DNARESUMO
Previous studies in other African countries have shown high prevalences of Isospora belli and Cryptosporidium parvum infections in acquired immunodeficiency syndrome (AIDS) patients with chronic diarrhoea. However, there is lack of information regarding these infectious agents in Ethiopian AIDS patients. Thus, this investigation has been aimed at determining the prevalence of Cryptosporidium and other related gastrointestinal parasites in AIDS patients with diarrhoea in seven Addis Ababa hospitals. Stool specimens from 246 clinically diagnosed AIDS patients were parasitologically screened for parasitic infections constituting HIV-negative with diarrhoea and HIV-positive without diarrhoea control groups. A variety of intestinal protozoa and helminths were found in 50% of AIDS patients and 42% of the controls. Cryptosporidiosis was detected in 38(25.9%), Isosporiasis in two (1.4%), and Blastocystosis in one (0.7%) of the AIDS patients with diarrhoea. The occurrence of cryptosporidiosis among the AIDS patients and possible explanation of the increasingly high study subjects with diarrhoea but without identifiable parasites is discussed.