The 2009 H1N1 vaccine seems to be as safe as the regular seasonal flu vaccine, according to the World Health Organization (WHO). At a virtual press briefing on November 19, 2009, Dr. Marie-Paule Kieny, director of the WHO’s Initiative for Vaccine Research, indicated that, for every 10,000 doses of H1N1 vaccine given, there is about 1 adverse event.

The most common adverse reactions associated with the H1N1 vaccine include pain at the injection site, swelling, redness, fever, headache, muscle pain, and fatigue. These reactions typically resolve within 1 or 2 days. Of the H1N1 vaccine adverse events reported, about 5 of every 100 are considered serious. Serious adverse events reported so far include 30 deaths and 12 cases of Guillain-Barre syndrome (GBS), an immune disorder affecting the peripheral nervous system. However, Dr. Kieny emphasized that none of the deaths reported to date has been confirmed to be caused by the H1N1 vaccine and all cases of GBS were transient.

It appears that there is no difference between the safety of the seasonal and H1N1 vaccine, as the number of adverse events for both vaccines is comparable. Approximately 65 million doses of H1N1 vaccine have been given so far, and the WHO expects to begin shipping the H1N1 vaccine to developing countries by the end of November.
 

Source:

World Health Organization website.