Prevention and Control - HIV Virus infection

Prevention and Control

These include the following steps: (a) health education, ( b) screening of blood and blood products, (c) infection con-trol, and (d) vaccine development.

◗ Health education

Health education plays a key and important role for the prevention of AIDS in the absence of a suitable vaccine. Health education is aimed at behavioral changes and maintenance of a lifestyle that minimizes or eliminates the risk of transmission. Health education includes the following:

·           Safe sexual practice by using a condom, which prevents transmission of the virus.

·           Not sharing unsterile needles or syringes.

·           Information to HIV-positive women regarding the risk of vertical transmission of HIV to infants.

◗ Screening of blood and blood products

It is essential to screen potential blood donors before they donate blood or blood products before use. The infected per-sons who are tested positive for HIV should refrain from donat-ing blood, plasma, body organs, other tissues, or sperm. The blood of the donors should be screened for HIV-1 and HIV-2 antibodies by screening tests, such as ELISA. Regular screen-ing of blood for HIV antibodies before transfusion has reduced considerably the transmission of HIV by contaminated blood.

◗ Infection control

Infection control methods include the use of universal blood and body fluids precautions. These universal precautions include wearing protective clothings, such as gloves, masks, gown, etc., and using other barriers to prevent exposure to blood products. These also include disinfection of contaminated surface with 10% household bleach, 70% ethanol or isopropanol, 2% glutaraldehyde, 4% formaldehyde, or 6% hydrogen peroxide. Washing clothes in hot water with adequate detergents is effective to kill HIV.

◗ Vaccine development

A safe and effective vaccine is yet to be available against HIV. An ideal HIV vaccine is that which would:

·           prevent acquisition of the virus by an adult during sexual intercourse,

·           prevent transmission of virus to infants of HIV-positive mothers, and

·           also block the progression of the disease.

There are many scientific obstacles to the development of AIDS vaccine. This is mainly due to various problems unique to the HIV as mentioned below:

a)        Antigenic diversity and hypervariability of the virus, as the antigenicity of the virus changes readily through mutation.

b)       Transmission of the disease by mucosal route—initial protection should require the production of secretory antibodies to prevent sexual transmission and acquisition of the virus.

c)        Transmission of the virus by infected cells.

d)       Latency of the virus—the virus can be spread through syncytium and remain latent, thereby remaining protected from antibodies.

e)        Integration of the virus genome into the host cell chromosome.

f)         Rapid emergence of viral escape mutants in the host—the high error rate of the viral reverse transcriptase leads to continuous mutations in the HIV genome.