Many parts of the U.S. are in the throes of the flu season. And as usual, plenty of misinformation is circulating and passed from one person to another, just like the flu virus. The good news is that unlike more egregious examples of waste and greed in the U.S. healthcare system, the anti-flu crowd is mostly well-meaning people who simply overstate the value of our existing flu therapies.
So practice good mental hygiene and wash your minds of your pre-existing thoughts before we consider some facts.
The Vaccine
The vaccine is not the miracle intervention many hope for. For example, a meta-analysis in Lancet identified 31 studies that were either randomized controlled trials or good observational studies with large patient populations and good tracking. It concluded:
“Influenza vaccines can provide moderate protection against virologically confirmed influenza, but such protection is greatly reduced or absent in some seasons. Evidence for protection in adults aged 65 years or older is lacking.”
In other words, every year the vaccine manufacturers sample the flu in the southern hemisphere to make an educated guess of the strains that will show up when the northern hemisphere goes into flu season. Some years they guess well; others they don’t.
Another meta-analysis was performed by the Cochrane collaborative. They identified 40 trials that included 70,000 subjects that compared those who received vaccine vs. those who got no treatment or placebo. They concluded:
“In the relatively uncommon circumstance of vaccine matching the viral circulating strain and high circulation, 4% of unvaccinated people versus 1% of vaccinated people developed influenza symptoms (italics added). The corresponding figures for poor vaccine matching were 2% and 1%. These differences were not likely to be due to chance. Vaccination had a modest effect on time off work and had no effect on hospital admissions or complication rates. Inactivated vaccines caused local harms and an estimated 1.6 additional cases of Guillain-Barré Syndrome per million vaccinations. The harms evidence base is limited.”
In other words, they found that the vast majority of patients with flu-like illness in a given flu season do not have the flu. They have any number of dozens of other respiratory system viruses that act just like the flu.
Another recent report in BMJ added to this evidence base, concluding that “evidence for protection in adults 65 years of age and older (who represent over 90% of deaths from flu) … is lacking.” And further, “there is no credible evidence that in inactivated vaccines have any effect other than saving on average half a working day in healthy adults and avoiding symptoms in those who least need it: healthy adults and adolescents. Depending on the season, you need to immunize 33 to 99 adults to avoid one set of symptoms.”
Death Statistics
The annual death toll commonly reported in the media. The basic problem is that for decades flu and pneumonia deaths are combined. The CDC even uses modeling to impute deaths from heart failure, etc. that may have been affected by the flu, even though the death certificate does not list influenza as a cause of death. From the CDC website:
What are seasonal influenza-related deaths?
Seasonal influenza-related deaths are deaths that occur in people for whom seasonal influenza infection was likely a contributor to the cause of death, but not necessarily the primary cause of death.
Does CDC know the exact number of people who die from seasonal flu each year?
CDC does not know exactly how many people die from seasonal flu each year. There are several reasons for this.
And:
Does CDC think that influenza causes most P&I deaths?
No, only a small proportion of deaths in either of these two categories are estimated to be influenza-related. CDC estimated that only 8.5% of all pneumonia and influenza deaths and only 2.1% of all respiratory and circulatory deaths were influenza-related.
Enough said. And finally:
Tamiflu
Since 2009, the BMJ has waged a public struggle against Genentech/Roche over the transparency of their clinical trial data. The following is from their website:
“Our first open data campaign initiative relates to a public promise Roche made in 2009 to release full clinical trial reports in response to an investigation by the BMJ and Cochrane collaborators Peter Doshi and Tom Jefferson.
The bottom line:
- WHO recommends Tamiflu, but has not vetted the Tamiflu data.
- EMA approved Tamiflu, but did not review the full Tamiflu dataset.
- CDC and ECDC encourage the use and stockpiling of Tamiflu, but did not vet the Tamiflu data.
- The majority of Roche’s Phase III treatment trials remain unpublished over a decade after completion.
- In Dec 2009, Roche publicly promised independent scientists access to “full study reports” for selected Tamiflu trials, but to date the company has not made even one full report available.”
In other words, the BMJ and others (such as the noted critic of the Pharma industry, Ben Goldacre) believe that the manufacturer has refused to publish the majority of its clinical trial data that is not favorable to the drug. The efforts to force full disclosure continue in the UK courts and regulatory agencies.
But let’s put this issue aside for a moment. What do the published RCTs of tamiflu say? Not much. From a Cochrane review of tamiflu and similar drugs in children:
“This review found that treatment with neuraminidase inhibitors was only associated with modest clinical benefit in children with proven influenza. Treatment with oseltamivir or zanamivir shortened the duration of illness in healthy children by about one day.”
And from another review in Lancet about the efficacy of the vaccine in the elderly:
“[F]ew trials have included elderly people, and especially those aged at least 70 years, the age-group that accounts for three-quarters of all influenza-related deaths. … The remaining evidence base is currently insufficient to indicate the magnitude of the mortality benefit, if any, that elderly people derive from the vaccination programme.”
In spite of this lack of evidence, governments around the world have stockpiled hundreds of millions of dollars worth of tamiflu for flu outbreaks.
Conclusions
Illness and deaths go up in flu season and the healthcare community wants to do something about it. Unfortunately, the evidence is that both our preventive vaccines and acute treatments don’t do very much. We can’t control some of the things we wish we could control. It’s the human condition to catch bad flus/colds in the winter. We should more humbly accept that this is just the way it is, and that spending hundreds of millions of dollars to identify and treat possible influenza cases is mostly a waste of time and money.
P.S. Just to be clear, because of cultural and medico-legal realities, I’m not suggesting that any U.S. physician rebel against standard flu treatment approaches. We need support from some national organization to take this bold move, which is unlikely to happen anytime soon.
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