HIV/AIDS and Antiretroviral Therapy

HIV/AIDS and
Antiretroviral Therapy

The risk of transmitting HIV/AIDS depends on the mode of transmission, the infectiousness of the person with HIV, and the susceptibility of the person exposed (table 3.1). Despite these relatively limited modes of transmission, few countries have slowed or reversed the growing HIV/AIDS epidemic. NACO estimates that 84 percent of new HIV infections occur through heterosexual transmission. Reduction of transmission through vaginal intercourse should therefore have the greatest impact on epidemic dynamics.
Strategies to reduce sexual transmission in India would involve:

Prevention and cure drugs treatment options with Symptom Checker  (AIDS-HIV-infection)

•Reducing the probability of HIV transmission during each sexual contact
by increasing condom use.

• Reducing the number of sexual partners through behavioral interventions

for commercial sex workers and the general population.
• Reducing the level and duration of infectiousness through medical interventions,
including treatment of sexually transmitted infections and use of antiretroviral therapy.

Infectiousness depends on the concentration of HIV in genital secretions and on the strain of virus a person carries (Dyer and others 1997; Hart and others 1999). Studies of couples in which one partner is infected and the other is not (so-called “discordant” couples) have shown that the risk to the uninfected partner rises dramatically with the concentration of virus in blood plasma (Gray and others 2001). When the plasma viral load is less than 1,500 copies per cubic millimeter, no transmission is observed. Therisk of infection increases to 1 per 10,000 episodes of intercourse at a plasma viral load level of 3,500 copies per cubic millimeter and to 1 per 200 episodes at a plasma viral load greater than 50,000 copies per cubic millimeter.
By increasing viral shedding, increasing the number of cells receptive to HIV and the number of HIV receptors per cell, the presence of a classic sexually transmitted disease, such as chancroid or gonorrhea, may
increase the risk of HIV transmission for both men and women by a factor of as much as 10, accelerating the spread of the epidemic (Holmes and others 1998; Over and Piot 1993). Different types of HIV may have different capacities for infection. Subtype C, the subtype most commonly found in India, is believed to be the
most infectious. Drug-resistant strains of the virus that are emerging in all parts of the world in response to antiretroviral therapy may be either more or less infectious than strains of the virus that have never been subjected toselection pressure from antiretroviral therapy.