Increased prevalence of retrovirus infections among older women in Africa.
Recent studies of HIV-2 have suggested an increased incidence and prevalence among women older than 45 y compared with younger women. We therefore examined whether this phenomenon applied generally to all 3 major retroviruses, HIV-1, HIV-2 and HTLV-I, among women in Africa. We conducted a MedLine search from 1987 to 1997, using the keywords Africa and HIV-1, HIV-2 or HTLV, respectively. Community studies, national surveys and studies on professional cohorts were selected. Age groups > 45/50 y were compared with the age group with the lowest female/male prevalence ratio between 20 and 44 y of age. Thirty-one studies had sufficient data to be included. The female/male odds ratio (OR) for seropositivity was calculated for the old and the young age groups, respectively, providing the ratio of odds ratios: OR (old)/OR (young). Summary ratios for studies of all 3 retroviruses were estimated. In general we found a higher female/male prevalence ratio in the age group over 45/50 y than in the younger age group. For HIV-1 the odds ratio was 1.82 times [95% confidence interval (CI) 1.19-2.79] higher in the old age group than in the young group. For HIV-2 it was 1.97 [95% CI 0.95-4.08], and for HTLV-I it was 2.02 [95% CI 0.99-4.14] times higher. For all 3 viruses combined, the ratio was 1.88 [95% CI 1.36-2.61]. The few incidence studies of HIV-1 and HIV-2 indicated a similar tendency. Since differential mortality is unlikely to explain the pattern, the increase in the HIV-1, HIV-2 and HTLV-I female/male prevalence ratio suggests that older women may have increased exposure or susceptibility to all 3 retrovirus infections.
Holmgren
B
B
Projecto de Saúde de Bandim, Bissau, Guinea-Bissau.
Aaby
P
P
Jensen
H
H
Larsen
O
O
da Silva
Z
Z
Lisse
I M
IM
D000328:Adult; D000349:Africa / Q000453:epidemiology; D017677:Age Distribution; D005260:Female; D015658:HIV Infections / Q000145:classification / Q000453:epidemiology*; D015497:HIV-1; D015498:HIV-2; D015368:Human T-lymphotropic virus 1; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012192:Retroviridae Infections / Q000453:epidemiology*; D017678:Sex Distribution