Novel H1N1-International Status Update; WHO Addresses Vaccine Safety Concerns

The World Health Organization (WHO) has reported a status update with respect to international statistics on the Novel H1N1 virus.  As of August 13, 2009, WHO regions have reported182,166 laboratory-confirmed cases of the Novel H1N1 influenza virus (new H1N1) with 1,799 deaths.  The  laboratory-confirmed cases are believed to be an underestimation of total H1N1 cases in the world as many countries have shifted to strategies of clinical confirmation and prioritization of laboratory testing only for persons with severe illness and/or high risk conditions. 

At present, the Novel H1N1 virus continues to be the dominant Influenza virus in circulation in the world – 71% of all Influenza viruses currently detected globally are the new H1N1.  The Novel H1N1 virus also currently accounts for 66% of Influenza viruses in the Northern Hemisphere and 89% of Influenza viruses in the Southern Hemisphere. 

According to WHO, in the face of the rapid spread of a pandemic virus worldwide, regulatory authorities often have to allow for great flexibility in developing procedures for fast-tracking the approval and licensing of pandemic vaccines.  However, numerous media reports seem to have expressed concern about the safety of vaccines for the H1N1 pandemic influenza due to the fast-tracking procedures in place to bring the vaccine to the market.  The main concern is that the fast-tracking approval of a drug or vaccine generally leads to a situation in which the true adverse effects of the administered agent are fully observed only after the agent has appeared on the market (i.e. at the time of post-marketing surveillance).  Other concerns include the vaccine manufacturing procedure itself.  Numerous individuals appear to be concerned with the use of eggs in the H1N1 vaccine manufacturing process.

Due to the above concers, WHO headquarters issued a briefing recently stating that the regulatory procedures in place for the licensing of pandemic vaccines, including procedures for expediting regulatory approval, are rigorous and do not compromise safety or quality controls.

For those concerned about the safety of the H1N1 vaccine and/or its manufacturing process, here are some useful resources for further study:

WHO latest briefing on the safety of pandemic vaccines

Pandemic influenza vaccine manufacturing process and timeline