Flu complications risky for preemies

Premature infants are at increased risk of severe flu-related complications, but these babies arent flagged as a priority group to receive pandemic influenza vaccines, a Canadian researcher says.

Around a quarter of healthy children who are diagnosed with flu or show features of the respiratory illness develop complications from pneumonia and ear infections to death. Now researchers have analyzed data from 27 studies to see which groups of children with flu are more likely to be admitted to hospital.

The key new finding is that children under the age of two who were born prematurely and were either prediagnosed with flu or who saw a health-care provider for flu-like illness were about twice as likely to be admitted to hospital as other children, said Dr. Peter Gill, a pediatric resident at the Hospital for Sick Children in Toronto.

But current definitions of at-risk groups dont include prematurity and should be updated, Gill and his co-authors said in Wednesdays issue of The Lancet Respiratory Medicine. The Canadian guideline currently recommends flu vaccines for all children over six months of age but doesnt single out prematurity.

Its important to identify high-risk groups particularly during a pandemic or flu outbreak when resources are limited and those at greatest risk need to be triaged, Gill said.

"This is a new population, which is quite a large population in terms of about 11 per cent of deliveries in North America are preterm, a large population that hasn't been previously identified as at risk that is," he said.

Primary care providers should therefore continue to identify children, in particular, those born prematurely, as high-risk groups when they educate families about the importance of vaccination.

Children under six months of age cant be immunized against flu, so its important to ensure that parents and other household contacts of these infants get the shot, Gill said.

• Flu shots while pregnant tied to lower preterm birth risk

Last month, the Canadian Paediatric Society released a position statement on the benefits of flu vaccines in pregnancy to protect infants under the age of six months.

The latest findings also backed that children with illnesses such as neurological disorders, sickle cell disease and diabetes are at greater risk of flu-related complications.

Its not clear whether the risk from prematurity is only in infancy or if it persists beyond age two, Harish Nair from the University of Edinburgh in the UK and Marc-Alain Widdowson from the U.S. Centers for Disease Control and Protection in Atlanta said in a journal commentary published with the study.

The studys authors also didnt have detailed enough data to define prematurity more specifically in terms of gestational age.

The UK National Institute for Health Research funded the research.