Cases of HIV attacks with multiple strains more prevalent than thought previously Cases in which an HIV-positive person is infected with more than one stress of the virus are more common than previously believed, Canadian and U.S. Mon at the XVI International Helps Conference in Toronto scientists said, CanWest News Services/Vancouver Sun reports generic sildenafil . Researchers reported that eight so-called superinfection situations have been discovered among 57 HIV-positive ladies in Mombasa, Kenya. According to the study, many of the women contracted a second stress of the virus within twelve months of their first an infection, while other infections happened up to five years after their initial infection. While it is unclear if the risk of contracting multiple strains of HIV is as likely as being infected for the first time, data are beginning to recommend that reinfection is usually a concern, Julie Overbaugh, associate system head at the Fred Hutchinson Cancer Research Center, said, adding that although the study is regarded as the biggest of its kind, only 57 ladies were involved.