Written by Dr. Elizabeth Ray , CNN Originally published on CNN
The US Centers for Disease Control and Prevention has said, in a recent study published in the medical journal Advances in Pediatric Infectious Diseases, that more people who were vaccinated against the flu have fewer complications.
The report is the first in a series of possible link studies showing whether vaccinated individuals were more likely to be protected against serious flu complications than those who had not been vaccinated.
In the study, researchers looked at 16 countries where the flu shot is most frequently available and among most people between the ages of 20 and 64 years.
They found people who were vaccinated had fewer cases of bacterial pneumonia, hospitalization and death compared to those who weren’t vaccinated.
Among people who had pneumonia from the flu, the rate of infection was about 9.5 per 100,000 during the week of the flu season the data were collected, versus about 12.4 per 100,000 during the weeks following the flu season, the report shows.
The study also shows that the risk of hospitalized after being diagnosed with flu was 11.2 per 100,000 among those who had been vaccinated versus 13.6 per 100,000 among those who hadn’t been vaccinated.
A risk rate of death wasn’t identified in the study, but is on par with what would be expected in non-vaccinated individuals, the CDC said.
Also shown in the report was that a higher vaccination rate “significantly” decreased the risk of hospitalization or death among those who had been diagnosed with the flu, regardless of who caught the illness.
Overall, the study did not show an increase in risk of death among vaccinated individuals, but it was unclear whether that would remain true because of a high infection rate in some countries, the CDC said.
Another way the report looked at the question was by tracking Americans who got vaccinated before heading abroad and comparing that group to those who didn’t get vaccinated. In the study, 55% of those with travel insurance used it to receive a flu shot, the CDC said.
In addition, 40% of travelers who lacked insurance used travel insurance to get the vaccine, the CDC reported.
Although the report was limited to the flu shot, the authors say the findings may be applied to other diseases as well.