People aids dating
A genotype survey of 4,166 individuals revealed a cline of allele frequencies of 0%–14% across Eurasia, whereas the variant is absent among native African, American Indian, and East Asian ethnic groups.
These can be done in individuals whose characteristics are known and can be controlled for, and if the relationship truly is monogamous then infections by acute STIs and from outsiders can be ruled out.
One disadvantage is that condom use in long-term relationships, even in serodiscordant couples, is relatively rare.
Another is that the HIV-positive partner will be chronically infected and so will not have the very high viral load characteristic of acute HIV infection.
Thirdly, in long-term serodiscordant relationships, studies have shown that the HIV-negative partner can acquire a degree of immunity to their partner’s HIV.
Studies of condom efficacy have therefore largely contrasted HIV and STI incidence or prevalence in people who claim 100% consistent use against people who use them inconsistently or not at all.
For these reasons, HIV transmission within long-term serodiscordant relationships, especially heterosexual ones, may be rarer than it is between casual sex partners.
However, the same studies show that condoms come off the penis altogether 3 to 5% of the time but may slip down (but not off) up to 13% of the time.The efficacy of an intervention is how well it works in a scientific trial or when people use it as indicated, i.e.consistently; its effectiveness is how well it actually works to prevent disease or infection in a given population, given actual levels of use.These margins of uncertainty...should represent an obligation on the part of the health ministries and all these campaigns to act in the same way as they do with regard to cigarettes, which they state to be a danger." Finding out the degree to which condoms protect against HIV is important both for HIV-negative people who want to protect themselves against HIV, and HIV-positive people who want to avoid transmitting it.Knowing how well they protect against other STIs is important for sexual health in general and may be particularly important for people with HIV, who may be more vulnerable to the effects of certain STIs.chemokine and the human immunodeficiency virus (HIV)–1 coreceptor on lymphoid cells, leading to strong resistance against HIV-1 infection and AIDS.