The flu vaccine is effective at preventing death in children — whether or not they have an underlying medical condition that may contribute to their illness, according to a new study from the U.S. Centers for Disease Control and Prevention.
Researchers examined the cases of 358 children who had confirmed influenza infections and then died. They compared the details of these cases to those of four different national surveys of children in the same age groups who did not die after coming down with the flu.
Using statistical modeling techniques, the researchers determined that the odds of dying after an influenza infection were far greater for children who hadn’t been immunized. According to the CDC study, vaccination appears to reduce the risk of flu-related deaths by half among children with high-risk medical conditions — and by nearly two-thirds among children without such conditions.
The analysis is important because it’s believed to be the first of its kind that zeroes in on deaths among laboratory-confirmed flu cases to gauge vaccine effectiveness, instead of relying on less-specific “all cause” death rates, which the CDC researchers believe “have overestimated effects of influenza vaccination on mortality in older adults.”
It’s more difficult to confirm flu cases in older adults using symptoms such as fever, cough or culturing samples in the lab.
Flu-related deaths are required to be tested only in children, so adult flu-death data may miss cases that were attributed to the other types of illness often present in adults who end up dying after becoming infected with the flu.
For the current flu season, which has now killed 79 people in San Diego County, the CDC recently estimated that this year’s vaccine is 48 percent effective for adults. However, that estimate examines whether or not inoculation can prevent infection, not death.