Pneumonia in Children Often Caused by Respiratory Virus

Pneumonia in children is most often detected by causes of respiratory viruses — not bacterial infections, according to research published in the New England Journal of Medicine.

A multifaceted team of researchers from the Etiology of Pneumonia in the Community (EPIC) study conducted a prospective, population based analysis of community acquired pneumonia hospitalizations among US children. The researchers aimed to address important gaps in knowledge about pneumonia by demonstrating that the burden of pneumonia-related hospitalization is the highest among children less than 5 years old.

A total of 2,638 children younger than 18 years old were enrolled in the study, and were considered eligible if they were admitted with pneumonia to a number of children’s hospitals across the country between January 2010 to June 2012. The pneumonia cases were confirmed by chest X ray, and nasal, throat, and blood samples were obtained from all the children to identify the cause of pneumonia.

The researchers discovered that 81 percent of cases examined were caused by viral infections. Only 8 percent of the pneumonia cases were caused by bacterial infections, and 7 percent of the cases were both viral and bacterial, the researchers found. RSV and rhinovirus were the leading causes of pneumonia in the children, followed by human metapneumonoviros (HMPV), adenovirus, parainfluenza virus, and coronavirus.

“What this tells us is that viruses are important causes of pneumonia,” study co author Kathryn Edwards, MD said in a press release. “But it also tells us that with the routinely administered pneumococcal and haemophilus vaccines given to children, that we have virtually eliminated most bacteria as causes of pneumonia.”

About 45 percent of the enrolled patients were female, the researchers noted. A third of the participants were black, 40 percent white, 19 percent Hispanic, and the remaining 8 percent were identified as another race or ethnic group. About half of the children had an underlying health condition, the researchers reported. On average, the children were aged about 2 years. Of the children admitted to the hospital, 21 percent of them had to be admitted to the intensive care unit, and 3 died.

“Pneumonia is a leading cause of hospitalization and is nearly always treated with antibiotics, but results from the EPIC study indicate we could drastically reduce antibiotic use overall, and when we do use antibiotics, we could do a much better job of limiting the use of broad spectrum antibiotics,” continued study leader Derek Williams, MD, MPH in the press release. “Unfortunately, differentiating viral from bacterial causes of pneumonia is not always clear. We are now trying to unravel that mystery to better understand the best way to treat pneumonia, when to use antibiotics, what antibiotics to use, and how to prevent it.”