The effects of HIV-2 infection in a rural area of Guinea-Bissau

The objective of this study was to investigate the clinical and immunologic effects and the pattern of mortality associated with HIV-2 infection. A rural community in Guinea-Bissau was the setting for this serologic screening of 2774 subjects aged > 14 years which was followed by studies of the prevalence of clinical and immunologic abnormalities among 133 subjects with HIV-2 infection and 160 seronegative controls. Also included was surveillance of mortality among all subjects who were screened during a mean of 2 years of follow-up. Generalized lymphoadenopathy was the only clinical abnormality significantly associated with HIV-2 infection. Infection was associated with lower CD4 counts and higher beta2-microglobulin and neopterin levels. During follow-up 5.5% of infected subjects died compared with 1.8% of the seronegative (rate ratio adjusted for age and sex 3.5; 95% confidence interval [CI] 1.8 to 6.7). Proportional hazard regression analysis showed that the rate ratio varied with age (p = 0.003) and there was some evidence that the excess of mortality in infected subjects was in absolute terms least in the oldest subjects (trend test; p = 0.08). These findings support previous suggestions that HIV-2 is less pathogenic than HIV-1; the data also suggest that mortality associated with infection may be lower in older subjects. (authors)