By Henry Neondo
Women living in rural Zimbabwe are at risk of HIV infection due to genital lesions caused by a common waterborne parasite, a study conducted by Norwegian and Zimbawean researchers published in the February edition of the journal AIDS says.
“Caused by schistoma haemotobium parasite, the lesions increases the risk of women acquiring HIV infection threefold in”, says the report.
The schistoma parasite can be acquired by bathing in water infested with the parasite, or by drinking this water. Schistosomiasis infection is predominantly a rural problem in Africa and Asia.
Although the infection is known to cause genital tract lesions, no study had previously assessed whether schistosomiasis increases the risk of HIV infection in a similar way to genital lesions caused by sexually transmitted infections such as herpes.
Norwegian and Zimbabwean researchers carried out a cross-sectional study in rural north-western Zimbabwe, recruiting 527 women through a local clinic in Mupfure.
Forty-six per cent were found to have genital schistosomiasis at baseline, 29% were
According to the researchers, multivariate analysis showed that women with S.haematobium infection in the genitals were almost three times more likely to be HIV-positive.
However there was no significant difference in S. haematobium infection at baseline between the seroconverters and those who remained HIV-negative.
The authors suggest that genital schistosomiasis increases the risk of HIV infection because it causes genital lesions and `sandy patches` (areas that bleed easily) in the female genitals.
They say that S. haematobium also induces higher expression of the CCR5 receptor on the surface of T-cells, increasing the risk that those cells will become infected by HIV, and the parasite attracts immune system cells vulnerable to HIV infection into the surrounding tissue.