CDC report sheds light on pandemic H1N1 deaths in children

Lisa Schnirring Staff Writer

Sep 3, 2009 (CIDRAP News) – Though the pandemic H1N1 virus never faded from the scene during the summer, illnesses are starting to pick up again, particularly in the southeastern states where school has already started, Thomas Frieden, MD, director of the US Centers for Disease Control and Prevention (CDC) said today.

Frieden's comments came the same day the CDC released a report on pediatric deaths from novel H1N1 infections in children, which seem to be striking those with neurodevelopmental conditions the hardest and showing a bacterial pneumonia coinfection pattern, even in previously healthy children. The report appears in the Sep 4 issue of Morbidity and Mortality Weekly Report (MMWR).

Though there's no sign that novel H1N1 is becoming more deadly, the CDC is vigorously monitoring the virus and is prepared to change its approach to fighting the virus if needed, Frieden said.

The Department of Health and Human Services (HHS) today also issued an update on the pandemic H1N1 virus activity in five southern hemisphere countries, available on the flu.gov Web site. Though patterns there resemble the experience the United States had in the spring, the assessment suggests that indigenous populations may be disproportionately affected, he said.

"This information, plus the information on children, shows who is at highest risk and who we need to reach out the most," Frieden added.

The MMWR report includes 36 pediatric deaths that occurred from April through August 8. About two-thirds of the children had at least one underlying medical condition, such as cerebral palsy, muscular dystrophy, or chronic cardiac problems, which is higher than the percentage reported during recent flu seasons. CDC investigators found that, of 23 children who had lab results reported, 10 (43%) had bacterial coinfections. (Three involved methicillin-resistant Staphylococcus aureus.)

Of 31 children for whom medication treatment is known, 19 received antivirals, but only 2 were treated within 2 days of illness onset when the drugs are known to be most effective.

Frieden said though the pneumonia findings aren't unexpected, it's important for physicians to consider prescribing antibiotics for young patients who were ill and seemed to be recovering but then come back in with a high fever.

"The take-home message is that kids with underlying conditions are first in line when the vaccine is available," he said, adding that he will have his own kids receive the vaccine when campaigns begin. "I recommend all school kids get the vaccine."

In advance of the vaccine's arrival, expected in mid October, the CDC will be making efforts to give the public more information to assess vaccine risks, Frieden said. For example, the baseline rate for miscarriages the week after women receive the seasonal flu vaccine is just over 1,000 in 500,000 who receive the shot, about the same as the rate in unvaccinated women.

Until the vaccine arrives, the CDC is also asking Americans to take extra efforts to reduce the number of illnesses and the burden on the healthcare system, he said. Staying home when sick, hand washing, and proper cough and sneeze hygiene are vital, he said.

Most people, except for those with underlying conditions, will typically recover without testing and treatment. However, those who have severe symptoms such as trouble breathing or a recurrence of fever should contact their doctors.

CDC. Surveillance for pediatric deaths associated with 2009 pandemic influenza A (H1N1) virus infection, United States, April-August 2009. MMWR 2009 Sep 4;58(34):941-7 [Full text]