However, emerging research suggests that a disproportionate number of HIV transmissions—perhaps more than half—may originate from people during the first few months after they become infected with HIV. After someone becomes infected with HIV, the virus begins to replicate very quickly and the amount of virus in the body and bodily fluids such as the blood, semen, vaginal fluid and rectal fluid rises rapidly.
These symptoms generally appear about two weeks after infection occurs. An important part of this immune response includes the production of anti-HIV antibodies—small proteins made by certain immune cells, which can destroy HIV and prevent HIV from multiplying.
Once antibodies to HIV have been produced, HIV replication begins to slow down and the amount of virus in the body also known as the viral load gradually decreases. Unfortunately, antibodies cannot fully control HIV infection. Antibodies are not produced immediately after infection. In most people, it is possible to detect HIV antibodies in their blood within approximately 34 days of infection, although this can take up to three months in some individuals.
The amount of virus in the bodily fluids is highest during the acute HIV infection stage. After antibodies are produced, the viral load slowly decreases but does not stabilize at a lower level until up to six months after infection. The elevated viral load of someone recently infected with HIV is the main biological reason that they are more likely to transmit HIV to others at this time. The higher the viral load, the greater the risk is of transmitting HIV to others through unprotected sex.
Researchers estimate that the risk of transmitting HIV to another person from one act of unprotected sex is 26 times higher during the first three months after infection than during the months and years that follow. A high viral load alone is not enough to transmit HIV to another person; a recently infected individual also needs to be engaging in activities that can lead to the transmission of HIV, such as unprotected sex.
Unfortunately, a person who has recently been infected with HIV is more likely to be engaging in high-risk behaviours than a person who has been infected for a longer period of time. First, a recently infected individual is more likely to be engaging in high-risk behaviours because this is what led to their HIV infection.
Second, many recently infected individuals are unaware of their HIV status and therefore may not realize the importance of having safer sex. Because recently infected individuals account for a large number of HIV transmissions, identifying these individuals and helping them reduce their risk of passing HIV to others is critical to HIV prevention.
Research shows that when people become aware of their HIV infection and are provided with access to prevention and care services, most take measures to reduce their risk of transmitting HIV to others. As a consequence, many people who have recently become infected are unaware of their infection, as are their partners. Those who are recently infected may therefore continue to engage in high-risk behaviours until they are diagnosed with HIV.
Your organization may be able to play a role in overcoming these challenges, identifying these individuals, and reducing their risk of transmitting HIV to others. People who have recently become infected may be unlikely to get tested for several reasons. Most people who get HIV get it through anal or vaginal sex, or sharing needles, syringes, or other drug injection equipment for example, cookers. But there are powerful tools that can help prevent HIV transmission.
This section answers some of the most common questions about the risk of HIV transmission for different types of sex, injection drug use, and other activities. You can also download materials about HIV transmission. Skip directly to site content Skip directly to page options Skip directly to A-Z link. By contrast, the most commonly cited earlier estimates suggest that the HIV acute phase produces risk equivalent to extra months of chronic-phase infection. In the past five years, policy has consequently shifted toward programs that aim to keep HIV infections from spreading across a population by administering antiretroviral treatment as a preventive strategy.
However, individuals can only be treated once they are tested and diagnosed, and individuals rarely get tested within the first few months after infection. Because of this lag between infection and diagnosis, these "treatment as prevention" programs are unlikely to prevent transmission from acutely infected individuals, and some have questioned whether the strategy prevents much of HIV's spread. The new analysis suggests it's less likely that newly infected patients could undermine the strategy's impact.
By contrast, programs focused entirely on early identification of the disease may not be as cost-effective as once thought for controlling HIV's spread. Materials provided by University of Texas at Austin. Original written by Christine S Sinatra. Note: Content may be edited for style and length. They also found that each 1 log 10 drop in CD4 cell count was associated with a 2 log 10 increase in viral load in semen.
However, peak viral load in the semen of patients with advanced HIV infection was a mean of 1. Pilcher CD et al. Amplified transmission of HIV comparison of HIV-1 concentrations in semen and blood during acute and chronic infection. AIDS — , Primary tabs View active tab Preview.
Michael Carter. This article is more than 14 years old.
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