34.5 Antiviral drug against AIDS and some facts

 

• a)  Around 95% reduction of virus within 14 days after treatment with essentially any one of the following drug (nucleoside RT inhibitors, nonnucleoside RT inhibitiors, protease inhibitors).
  
  b)  Average half life of an HIV infected cell is about 24-48 hrs.

c)  Approximately 5% of total CD4+ T lymphocytes are productively infected in an infected individual at any given time during the latent period.

d)  The CD4+ T lymphocytes that are dying each day are being replaced nearly as fast as they die. This means that bone marrow, spleen and other reservoirs of T lymphocytes must be producing the cells at an exponential rate.

e)  Nearly within 7 -25 days after treatment with any one drug there is emergence of resistant virus.

f)  The rapid emergence of mutant virus suggests that the resistant virus was already present in the population at the time drug treatment was started.

g)  Resistant viruses do not grow quite as well as the wild-type viruses.

h)  Upon removal of the anti HIV drug, the wild type virus once again becomes predominant over the course of infection.

i)  One potential factor in the development of AIDS may be excessive stress on the immune system due to rapid turnover of T lymphocytes.

 

34.6 Control

• I. The use of condoms during sexual intercourse can reduce the chance of infection.

II. Avoiding intravenous drugs ( Needle sharing ).

III. Monitoring the blood for HIV before transfusion.

IV. Educating people regarding the cause, severity, and preventive measure of HIV.

V. Anti HIV drugs: These drugs are often given in combination of two or three. Nucleoside and Non-nucleoside analogues are called as reverse transcriptase inhibitors.

VI. Protease Inhibitors- saquinavir

VII.  Nucleoside analogues- Zidovudine and AZT

VIII.  Fusion inhibitors- Enfuvirtide

IX. Non- nucleoside analogues- Nevirapine