Trauma, such as open sores or ulcers in the genital area, can also increase the chance of infection. The cells on the penis are tougher to infect than those in the vagina or anus. "Fitter" viruses are more efficient at infecting new cells and then replicating themselves, Carlson says.Īnd the higher the initial barrier to this initial infection, the fitter the virus has to be to complete this process.ĭifferent parts of the body provide various levels of protection from the virus. Then the virus multiples and spreads to adjacent cells. To establish a long-term infection through sexual contact, an HIV virus must first infect a single cell on the genitals. "The average sequence in the population is probably average because it works best, and we found that that is true," says Jonathan Carlson, a computational biologist at Microsoft Research, who contributed to the study. Turned out, this pattern is the average DNA sequence that scientists find when they examine HIV strains in people from around the globe. These are couples in which one person is HIV-positive and the other is HIV-negative. To figure this out, a team at Microsoft Research and Emory University analyzed data from a decades-long study on HIV transmission between "discordant" heterosexual couples in Zambia. This made scientists wonder: Is there something special about the HIV versions making it through the filter? So the process is almost like a filter, letting only certain viruses through. This results in a large number of different HIV versions swarming about the body - each with its own genetic code.īut when HIV is transmitted through sex, usually only a single version of the virus establishes a long-term infection. So the chance of an infection increases in both situations.Īs HIV replicates inside a person, mutations are introduced into its DNA. And, most likely, reduced even further when men have sex with men. The restriction is less when women have sex with an HIV-positive man. This reduces the chance an infection occurs during sex. In other words, particular versions of the virus, with particular DNA sequences, are most likely to pass from a woman to a man. ![]() To Prevent HIV Infection, Couples Try Testing Together
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |