Doctors reported particular difficulties in persuading pregnant women to be vaccinated against the virus.
Skepticism has been growing in Britain and other European countries about health authorities’ handling of the H1N1 pandemic, because the number of people infected has been lower than originally feared.
Further, rates of infection by the 2009 H1N1 influenza virus may have peaked in late October, according to a new report by Quest Diagnostics.
As U.S. health officials struggle to vaccinate tens of millions of Americans against the pandemic of swine flu, some are now even looking regretfully at one easy way to instantly double or triple the number of doses available — by using an immune booster called an adjuvant.
These additives broaden the body’s response to a vaccine, reducing the amount of active ingredient called antigen needed. They are widely used in European flu vaccines as well as in Canada. But not in the United States — even though the federal government has spent nearly $700 million buying them.
The reason — people might not trust them.
Polls show that only about half of Americans plan to be vaccinated against H1N1. Of those who do not, about half say they worry about safety.
Further, The World Health Organization is looking into reports in Britain and the United States that the H1N1 flu may have developed resistance to Tamiflu in people with severely suppressed immune systems.
Britain’s Health Protection Agency (HPA) said five cases have been confirmed in Wales of patients infected with H1N1 resistant to Tamiflu.