Since April 2009, CDC has received reports of 285 laboratory-confirmed pediatric deaths: 241 due to 2009 H1N1, 42 pediatric deaths that were laboratory confirmed as influenza, but the flu virus subtype was not determined, and two pediatric deaths that were associated with seasonal influenza viruses. (Laboratory-confirmed deaths are thought to represent an undercount of the actual number. CDC has provided estimates about the number of 2009 H1N1 cases and related hospitalizations and deaths.
CDC estimates that between 34 million and 67 million cases of 2009 H1N1 occurred between April and November 14, 2009. The mid-level in this range is about 47 million people infected with 2009 H1N1.
CDC estimates that between about 154,000 and 303,000 2009 H1N1-related hospitalizations occurred between April and November 14, 2009. The mid-level in this range is about 213,000 H1N1-related hospitalizations.
CDC estimates that between about 7,070 and 13,930 2009 H1N1-related deaths occurred between April and November 14, 2009. The mid-level in this range is about 9,820 2009 H1N1-related deaths.
The ten thousand death estimate and the estimate that Adjuvants would have tripled vaccine availability and the successful use of adjuvants in Europe suggests that five thousand or more deaths could have been avoided by choosing to use adjuvants.
The researchers tested the vaccine in three different doses, with or without MF59 (adjuvant), in 176 adults between the ages of 18 and 50. Three weeks after the initial dose, volunteers who received the adjuvanted vaccine showed stronger immune responses than those who received the nonadjuvanted formulation.
MF59 has been used for years in Europe, but no adjuvanted flu vaccine has ever been licensed in the United States, and bringing one to market would require clearing regulatory hurdles or getting an emergency use authorization from the Food and Drug Administration.
There seems to be no controversy or issue in the mainstream media with what looks like a clear case of about 5,000+ excess H1N1 flu deaths (Katrina and 9/11 deaths combine to about 5000) based on a policy decision to not use adjuvants. Difficulty in explaining the science of adjuvants and the statistics of flu death estimation. Also, many in the media were telling people not to vaccinate against H1N1.
Last spring and summer, as the US Department of Health and Human Services (HHS) worked to rapidly produce an H1N1 vaccine, one key policy decision it made was about the use of vaccine additives known as adjuvants, enhancers that help improve the vaccine’s effectiveness. HHS decided against using adjuvants in H1N1 vaccine, but to have a supply on hand to add to the vaccine if it became necessary as an emergency provision. HHS weighed a number of factors in making this decision, including what strength of vaccine would be needed to deliver an adequate immunologic response, and the safety, effectiveness and availability of the H1N1 vaccine supply. When production problems reduced the supply of vaccine this fall, there was renewed media focus on the question of adjuvants. So just what are adjuvants and why was this decision important?
Why are vaccine adjuvants used?
Because vaccine adjuvants improve the body’s immune response, their use often allows for smaller amounts of the inactivated virus or bacterial components (the parts of the vaccine that prompt an immune response) to be used. This can stretch a vaccine supply, which can be important if supply is limited due to manufacturing problems.
According to the National Institute of Allergy an Infectious Diseases (NIAID), other important benefits from pairing adjuvants and vaccine are:
• To boost the immune response in certain age groups or in people with underlying health conditions who cannot mount an adequate immune response to a vaccine made without an adjuvant
• To broaden the immune response to the vaccine to provide better protection against a virus if it mutates.
Why is there a shortage of H1N1 vaccine and how might the use of adjuvants help alleviate it?
Earlier this fall, long lines formed as people tried to get the limited supply of H1N1 vaccine as it became available. Some 61 million doses of the vaccine had been used or were available to order in the US, far less than needed to vaccinate the original target groups which consisted of 159 million people. Drug manufacturing companies have struggled with an unpredictable virus that does not grow well in lab settings. Had adjuvants been used in the manufacturing process, some studies suggest the supply of H1N1 vaccine to date could have been tripled. For example, GlaxoSmithKline found a single shot of its H1N1 vaccine using an adjuvant and just 5.25 micrograms of antigen protected ninety-eight percent of volunteers. A standard dose without adjuvant takes 15 micrograms of antigen to provide similar effectiveness.
Why doesn’t the current
H1N1 vaccine contain an adjuvant?
The decision not to use an adjuvant was based on a number of factors, according to the Centers for Disease Control and Prevention (CDC). Effectiveness was one factor and clinical trials showed the H1N1 vaccine without adjuvant provided a good immune response, with a single dose providing protection for most healthy adults and older children.
Public perception of safety was also a factor. Producing the vaccine without adjuvant allowed H1N1 vaccine to be manufactured the same way as seasonal influenza vaccine, thereby avoiding the risk that public perception of anything new or “experimental” in the production process would cause people to decide against vaccine use, especially for children. Another factor was that the type of adjuvant proven effective in influenza vaccines is an oil-in-water emulsion-based adjuvant, which has not previously been approved for use in the US and would therefore require the FDA Commissioner to declare a public health emergency to clear the way for its use.