Flu Season Nearly Done/ CDC

Flu Season Winding Down / CDC

per CDC, Feb 8, 2013

ASO3 for the US avian flu stockpile / CIDRAP

I'm 3 months late on this.  Since this article came out, it became clearer that ASO3 caused narcolepsy in more countries than just Scandinavia and Ireland, and that adults were also at risk of developing narcolepsy after the vaccine.  And these are BAD cases of narcolepsy, not the minor cases I have seen in clinical practice.  There is also more Guillain-Barre with this vaccine.

But FDA asked the panel to comment on immunogenicity.  Sure enough, the vaccine does induce antibodies.  But we don't know if they work.  Not to worry.  After licensure, GSK can freely change the antigen.

FDA panel endorses H5N1 vaccine with adjuvant

Robert Roos  News Editor
Nov 15, 2012 (CIDRAP News) – A government advisory committee yesterday endorsed the safety and immunogenicity of an adjuvant-containing H5N1 influenza vaccine proposed for inclusion in the US pandemic emergency stockpile, signaling that it could become the first adjuvanted flu vaccine to win approval in the United States. 

On two unanimous votes, the Food and Drug Administration's (FDA's) Vaccines and Related Biological Products Advisory Committee (VRBPAC) said the immunogenicity and safety data on GlaxoSmithKline's (GSK's) H5N1 vaccine are adequate to support its licensure for use in adults. The aim is to strengthen the US stockpile for the threat of an H5N1 pandemic. 

The vaccine contains GSK's proprietary adjuvant AS03, which is used in several other GSK vaccines licensed in other countries. One of these, Pandemrix, used in Europe during the 2009 H1N1 flu pandemic, was linked with an increased risk of narcolepsy in children in Finland, Sweden, and Ireland. 

The purpose of the adjuvant is to induce a stronger immune response with less antigen or active ingredient, which AS03 achieves, according to GSK. The vaccine contains 3.75 micrograms (mcg) of antigen, compared with 15 mcg in standard flu vaccines without adjuvants. 

No seasonal flu vaccines used in the United States contain adjuvants, nor does the existing H5N1 vaccine in the US emergency stockpile. The government has acquired a supply of adjuvants for possible emergency use, but they are not part of a specific vaccine. 

The US Department of Health and Human Services (HHS) contracted with GSK to develop an H5N1 vaccine with antigen-sparing potential for use in the US Strategic National Stockpile, according to an FDA briefing document...

Another member, Gillian Air, PhD, said, "We don't know what these HI titers mean in terms of protection, but they've demonstrated this is immunogenic."

Elderly Vaccinated Danes more likely to get Flu A /H3N2 than the unvaccinated/ Eurosurveillance

Of 364 older Danes who were seropositive for H3N2 infection and about 1000 who were negative, it turned out those who were positive were a bit more likely to have been vaccinated this season for flu.

This may mean the vaccine was of no use due to high rates of mutation.  Or it could mean the vaccine-induced antibodies made you more likely to get sick.  (I have previously talked about the concept of blocking antibodies, which have occasionally been seen after introduction of a new vaccine, increasing the propensity to get the disease you are ostensibly being protected from. The new vaccine is soon taken off the market.)

The Flu Vaccine is a Paper Tiger, but the Nurse must wear a Paper Mask

"If you aren't vaccinated, you must wear a mask throughout flu season, or be fired!"

But what if you are in the 45-55% of healthcare workers who got vaccinated but lack immunity to circulating flu strains?  Shouldn't you be wearing a mask too?

What if you are in the 75-100% of vaccinated workers who get no protection some years (like last year)  because the vaccine was a poor match to the strains that actually circulated?  Shouldn't you be wearing masks, if the idea for the masks is to protect patients?

Not that there are any data suggesting a mask helps prevent the spread of flu when the wearer is not actively coughing or sneezing.

The European Center for Disease Prevention and Control, which may be more forthcoming about flu than CDC, points out flu vaccine effectiveness is thought to be in the 50% range this year, better than last year:

The vaccine effectiveness of the 2012/13 influenza vaccine is expected to be higher against influenza A(H3) infection than the especially low levels observed in Europe for the 2011/12 season. First indications from the UK confirm this although the estimates are still only in the range of 45% to 55%.

Also from the European Center, it appears the Europeans are so unconcerned about the need for HCW vaccinations they fail to even track them!  They don't trust the US/ CDC figures for vaccine effectiveness, either. 

Influenza Vaccine Coverage 

Seasonal vaccine coverage data are not yet available from the VENICE project* for the 2012/13 season. From the questionnaire, Latvia reported a lower proportion of people vaccinated while the UK (England) reported vaccination coverage comparable to 2011/12. Preliminary results from England estimate an uptake of >70% among those aged ≥65 years and around 50% in those under 65 years old in a clinical risk group, with a much higher uptake among pregnant women than during the previous season. Among the nursing homes affected by ARI outbreaks in France, the vaccine coverage (81%) was the lowest observed since 2003/04. This proportion is still to be confirmed, but it could reflect a lower national vaccine coverage among older people this season. The UK (Scotland) reported an increased uptake by pregnant women; 48.3% in those without risk factors and 64.6% in those with risk factors. Norway mentioned low vaccination coverage in risk groups. There is no information on immunisation of healthcare workers. Overall, it should be noted that there have been small declines in vaccine coverage in older age groups (the only risk group with consistent data) in a number of EU countries since the 2007/08 season [7]...

Vaccine effectivenessA recent American study [9] published an early estimate of influenza vaccine effectiveness non-adjusted for age of 62% (95% CI: 51%–71%) for 2012/13 which is better than for the previous season in the United States. A study from Canada showed somewhat lower levels [12]. However, it is essential to note that the US estimates were not adjusted for age, risk groups and other confounders and the proportions of circulating viruses in the USA and the EU are quite different this season: there are few A(H1N1) viruses circulating in the USA. Also, the analytic approach is different; in Europe the focus is more on effectiveness in the high risk groups. Hence, the US percentage should be interpreted with caution and may not reflect the vaccine effectiveness in Europe or for high risk groups. Early estimates of vaccine effectiveness in the UK have shown an overall adjusted vaccine effectiveness of 51% (CI: 27%–68%) with 49% against influenza A alone and 52% against influenza B.