How do antiviral drugs work?
Antiviral drugs work by preventing the influenza virus from reproducing. For treatment, antiviral medication must be taken within 48 hours of the onset of symptoms to be effective. Treatment at this stage can shorten illness by around a day and reduce hospitalizations by about 50%. Antivirals must be taken either before, or within 48 hours of, exposure. Antiviral drugs are not recommended for everybody. They are available to treat people more at risk of serious illness. Antiviral drugs for pandemic influenza Antiviral drugs are likely to have an important role in the prevention and treatment of pandemic influenza, especially when there is not enough vaccine available. However, it is important to note: • The effectiveness of antiviral drugs in a pandemic, and in particular in reducing the number of deaths in cases of severe disease, is not known. • It is recommended that antiviral drugs should be given to treat those at risk of serious illness. However, until the pandemic is underway, w
An antiviral drug interferes with the life cycle of a virus. Antiviral drugs for HIV can work at several points in the life cycle of the virus. An antiviral may prevent HIV from entering a cell by changing the cell membrane* or the envelope of the virus. Others may inhibit viral proteins* such as reverse transcriptase* and stop the production and integration* of viral DNA* into an infected cell. Some antivirals can block this viral DNA from forming new viruses. Others block the budding of new viruses from infected cells. What is an “effective” antiviral? There are several things to look for when considering an antiviral treatment for HIV infection: (1) Does the antiviral treatment cross the blood-brain barrier*? Unless the treatment can inhibit replication of HIV in the brain, HIV-infected individuals may develop dementia*. Several antivirals reviewed in this issue of BETA can cross the blood-brain barrier. However, AZT is the only antiviral proven effective by clinical trials in stopp
