More On The ACIP Meeting

 

 

# 3561

 

For a report on the ACIP committee recommendations read The ACIP Committee Recommendations

 

 

If you heard a collective sigh of relief today, it came from the 34% of the American population with a BMI (Body Mass Index) of greater than 30, which up until today had been cited as a possible risk factor for complications from the novel H1N1 virus.

 

Although it is a bit blurry (screen capture from the web broadcast) the slide above shows that the incidence of hospitalizations among those listed as obese by their BMI was practically the same as their prevalence in society.

 

Roughly 34% of Americans are obese, and roughly 38% of those hospitalized met that criteria.    While 6% are morbidly obese (BMI > 40), they only made up 7% of the hospitalized cases.

According to Dr. Anne Schuchat, the jury is still out on the morbidly obese, but right now there is no clear evidence that obesity – without some comorbid condition like diabetes – lends itself to a greater risk of complications from this flu.

 

Also, from the comments made during the ACIP meeting today, and those made by Dr. Anne Schuchat during the CDC conference call this afternoon, there obviously isn’t a lot of enthusiasm for using adjuvanted vaccines here in the United States.

 

The recommendations today out of the ACIP meeting were specifically for unadjuvanted vaccines.

 

Adjuvants are a somewhat controversial additive that are sometimes used to increase the immune response to a vaccine.  They are not currently licensed for inclusion in flu vaccines here in the US, and have only seen limited use in Europe for those over 65.  

 

They could be used if the HHS decided to go with an EUA (Emergency Use Authorization), but right now, there doesn’t seem to be much support for that idea.   

 

The HHS has stockpiled enough for millions of doses of vaccine, but the plans right now, according to Dr. Schuchat, are not to need them.

 

If the standard 15 µg dose should prove not to provoke an adequate immune response, or if the virus should antigenically drift away from the vaccine, an adjuvant might provoke a stronger, or broader immune response.  

 

Under those scenarios, a decision would have to be made weighing the potential (and largely unknown) risks versus the benefits.   There is scant data on the use of adjuvants for young adults and children, and the HHS obviously views adjuvants as a complication they’d rather not have to deal with.

 

Diplomatically, refusing to use adjuvants may prove a bit stickier, since using them could reduce the amount of antigen that Americans (who have large order for vaccine in place) would need.   That would, in turn, free up more antigen to make vaccine for other countries.

 

It remains to be seen how that little drama will play out.

 

So Adjuvants, at least for now, are not anticipated to be used here in the US, but they remain on the table.

 

It was pretty obvious, watching today’s telecast, that the panelists all wished they had more time, and more scientific data, with which to make their recommendations. 

 

The fall flu season is coming on like a freight train, and there simply isn’t enough time to conduct the type of studies and deliberations they would, no doubt, prefer. 

 

Clinical trials with a few hundred test subjects, however, really aren’t designed to pick up on a those rare – 1 in 100,000 – serious side effects. 

 

You generally only find those after a few million shots are given and well into the flu season.

Influenza vaccines generally have a pretty good record of safety.  Most side effects are minor, and self limiting.   A sore arm, a mild fever, maybe some body aches.   But gone in 24-48 hours.

 

But occasionally a serious side effect can occur.  Even though the incidence is very low, when you start giving hundreds of millions of shots, the number of adverse reactions will mount.

 

Some `incidents’ reported by vaccine recipients may not even be caused by the vaccine, but will evoke suspicion nonetheless.  I expect the press to be all over those, even before any causal link is established.

 

The good news here is, given that the over-65 crowd will be the last to receive the vaccine, the `noise’ that their less stable health conditions would interject shouldn’t be a factor.

 

But in the back of the minds of everyone making vaccine decisions, I’m sure, are the memories of 1976, and the worry that a new vaccine could produce a similar level of side effects. 

 

It may not be likely . . .but it is possible.  

 

The enormity of what the CDC, HHS, and public health departments around the country are about to undertake is absolutely staggering. There are a great many things that can go wrong, and undoubtedly, despite their best efforts . . . some things will go wrong.  

 

We need to accept that there are going to be bumps along the way, that not everything is going to come off as planned, and try to learn from these `challenges’ as best we can.

 

The lessons we learn now could prove invaluable if another, more severe pandemic should come down the pike in the years to come.