NEW YORK (AP) – The influenza vaccine is doing a pretty good job this season, protecting about half of the people who have received it, US health officials said Thursday.
Preliminary figures suggest that the vaccine is 47% effective in preventing influenza illness serious enough to send someone to the doctor. Health officials are generally satisfied if an influenza vaccine is effective in 40-60% of the population.
"These estimates are early, but they are encouraging," said Dr. Alicia Fry of the US Centers for Disease Control and Prevention.
Some 10,000 to 16,000 people have died from the flu and its complications this season, according to new estimates released Thursday.
Last winter was dominated by some sort of flu, and the weakness of the vaccine against this virus was one of the reasons it has been experiencing the most lethal influenza season for at least four decades. About 80,000 Americans died of the flu and its complications.
This winter, in most parts of the country, most diseases are caused by a somewhat milder virus against which vaccines tend to work better.
Globally, influenza is prevalent in 47 states, according to the latest data from the CDC. Health officials do not know if the flu season has peaked, Fry said.
They also see evidence that a more serious influenza virus is spreading to more states.
Dr. William Schaffner, an infectious disease specialist at Vanderbilt University, misunderstands why it is uncommon to see a new wave of more serious illnesses in a season dominated by a less serious influenza virus.
The first estimates of vaccine activity offer only a fuzzy picture. For example, there were not enough sick patients of different ages to produce a reliable estimate of the situation in the elderly, who are more prone to the flu and its complications.
Some other types of vaccines, such as measles, mumps and rubella, are much more effective than influenza vaccines in preventing the disease. But experts say flu is a hard-to-reach and evasive target.
An influenza vaccine that works about half the time "is the best that science can produce at the moment," said Schaffner.
The Health and Science Department of the Associated Press is receiving support from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.
Copyright © Associated Press. All rights reserved. This material may not be published, disseminated, rewritten or redistributed.