Studies Underscore Deadly Risks of Flu, Highlight Benefits of School-based Vaccinations

Study results presented at IDWeek 2012 show that influenza can pose fatal health risks even to otherwise healthy children with no serious underlying medical conditions. They also revealed that children who were vaccinated at school were much less likely to get the flu, leading to fewer school absences.

Researchers presented results of two pediatric studies on flu dangers and benefits of school-based vaccination efforts during a press conference held at IDWeek 2012, the first joint annual meeting of the Infectious Diseases Society of America (ISDSA), Society for Healthcare Epidemiology of America (SHEA), HIV Medicine Association (HIVMA), and Pediatric Infectious Diseases Society (PIDS).

Public health experts emphasized that too many adults and children die every year from influenza complications. “Influenza can be a really dangerous disease for children both with and without high-risk medical conditions,” said Karen Wong, MD, an epidemic intelligence service officer with the Centers for Disease Control and Prevention (CDC). Wong’s study looked at all influenza-associated deaths in children during the last eight years of flu seasons in the US.

From 2004 to 2012, a total of 829 children died, often quickly with a swift progression of symptoms. “For instance, a third of these children died within three days of their first symptoms,” Wong said. Many had underlying medical conditions rarely found in children, such as neurologic or genetic disorders. More common medical illnesses such as asthma also were recorded, she said.

“This study really highlights the vulnerability of children with underlying medical conditions to influenza complications,” Wong said.

The CDC-supported study also found that about 40% of those who died had been healthy with no known medical conditions to put them at high risk of serious flu complications. In addition, young healthy patients died sooner. “So these were otherwise healthy children who suffered devastating complications of influenza, and it really shows that any child can be at risk not just those with medical conditions,” noted Wong.

The young, healthy patients died sooner and more often at home before there was time to admit them to a hospital, Wong said. More than a third of the children who died were under five years old, a recognized high-risk age group, and 11% were babies too young for vaccinations.

The CDC recommends a yearly flu vaccine for everyone six months of age or older, regardless of whether they have high-risk medical conditions. Vaccinations are particularly important for family members and care givers who spend time around young or sick children, Wong said.

“Deaths can occur very quickly, so it’s best to be protected before the flu hits,” Wong said.

One way to lower rates of influenza among children is to vaccinate them through school-based programs, according to a second study also presented. It makes sense to make vaccinations available at the place where you find children in large numbers, said lead researcher Pia Pannaraj, MD, an assistant professor of pediatrics at the University of Southern California and Children’s Hospital, Los Angeles.

During the 2010 to 2011 academic year, researchers followed 4,500 children in eight Los Angeles area elementary schools who participated in the study to assess immunization efforts. Children at half the schools received vaccinations, while the other schools were monitored as a control group. Those who came down with respiratory symptoms were tested for influenza.

“What we found was that children who were vaccinated were three times less likely to get the flu and missed half the number of days of school compared to the children who were not vaccinated,” Pannaraj said.

Other notable findings were that children with the flu missed double the number of days compared to children who had other respiratory viruses that cause the common cold. In schools that had the vaccination program, flu rates were overall lower than those schools without the program, according to Pannaraj.