This rapid response report from the Canadian Agency for Drugs and Technologies in Health (CADTH) reviews the evidence on the clinical benefits and harms of antivirals for the treatment and prevention of pandemic influenza A (H1N1) and human avian influenza A (H5N1).

It found that, ‘There is limited evidence that oseltamivir is clinically effective for the treatment of pandemic influenza A (H1N1) and limited evidence that it is especially effective with treatment within 48 hours of symptom onset. There is insufficient evidence to make a definitive conclusion regarding the clinical effectiveness of antivirals for prophylaxis or treatment of pandemic influenza A(H1N1), and no evidence was identified regarding antiviral treatment for human avian influenza A(H5N1)’.

The Rapid Response Service is an information service for those involved in planning and providing health care in Canada. Rapid responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources and a summary of the best evidence on the topic that CADTH could identify using all reasonable efforts within the time allowed. Rapid responses should be considered along with other types of information and health care considerations