Studies indicate where 'flu vaccine can have benefits
Influenza vaccination can be used safely in patients with chronic pulmonary conditions, say researchers from Nottingham.
They suggest that routine influenza vaccination of older people with
asthma or chronic obstructive pulmonary disease (COPD) does not increase
short-term adverse respiratory outcomes.
Meanwhile data from another study, conducted by American researchers,
suggests that influenza vaccination in children aged six to 24 months
does not prevent acute otitis media, a benefit that has previously been
shown for older children.
The first study, published in Thorax (2003;58:835), involved a cohort
of 12,000 patients with asthma or COPD. During each influenza season
between 1991 and 1994 the researchers examined patient vaccination records,
corticosteroid prescriptions and incident diagnoses of asthma or COPD.
Although the data revealed increases in asthma and COPD diagnoses and
oral corticosteroid prescriptions on the day of vaccination, there was
no increased risk of adverse outcomes in the first two weeks following
vaccination. The researchers suggest that attendance for vaccination
would provide an opportunity to record diagnoses and to prescribe corticosteroids
in anticipation of future acute exacerbations.
“If a true adverse impact of the vaccine was present, we would
expect to see an increase in the recorded events in the days after vaccination,
and the lack of increase in events during this period is reassuring,” they
say.
The second study examined the effects of influenza vaccination compared
with placebo on the incidence of acute otitis media in 786 children under
two years of age. Overall, the researchers found no differences in the
occurrence of acute otitis media between the two groups. However, they
suggest that the vaccine might have provided a measure of protection
to children aged 19 to 24 months.
The data are at odds with those from previous studies, which have shown
reduced occurrence of acute otitis media following influenza vaccination.
The researchers suggest the discordant results could be because younger
children experience more non-influenza viral infections or because influenza
vaccination may not be as effective in this age group (JAMA 2003;290:1608). |
