[Prevention and therapeutical trials of a few current viral diseases]

Vaccines afford now good prevention of many viral diseases including Hepatitis B. In revenge, attempts of immunization against Herpes Virus types I and II did not result in large scale application of vaccination. Research for a vaccine against HIV encounters many difficulties due to virus variability and host reactions. The introduction of nucleosides analogues represented a great advance for antiviral chemotherapy. Weakly toxic drugs although efficacious against Herpes Virus replication are now available but they do not seem to prevent viral recurrences. As for HIV, its sensitivity to drugs like AZT has raised great hopes which were limited by their intrinsic toxicity. However, research and trials for more efficacious but less toxic drugs are further being developed.