More than 60 percent of pediatric pneumonia cases diagnosed worldwide are caused by viruses, according to a new study in The Lancet based on surveillance in seven countries. The study offers, for the first time in 30 years, new evidence-based recommendations for researchers looking to prevent childhood pneumonia.
Pneumonia is the leading cause of death worldwide among children under 5 years old, with approximately 800,000 fatalities and more than 100 million reported cases each year, the authors said.
The study, “Pneumonia Etiology Research for Child Health (PERCH),” included 4,232 cases of severe hospitalized pneumonia among children under 5 years and 5,325 community children without pneumonia. PERCH was conducted by researchers from the Johns Hopkins Bloomberg School of Public Health at study sites in in Bangladesh, The Gambia, Kenya, Mali, South Africa, Thailand, and Zambia.
The study took place from 2011 to 2014, when researchers took nasal and throat swabs as well as blood, sputum, and other fluid samples from case-patients and matched controls. Pneumonia was confirmed for more than 99 percent of cases on X-ray, and none of the study participants were HIV-positive.
The study produced several findings, including that 14 percent of all cases in the study population had vaccine-preventable illnesses, which means 15 million cases of pneumonia could be avoided each year with existing vaccines. Bacteria in general accounted for 27.3 percent of cases.
Viruses accounted for 61.4 percent of cases. Respiratory syncytial virus (RSV) accounted for nearly a third of the cases linked to viruses, and it and was the leading cause of severe pneumonia in all countries included in the study. Rhinovirus and parainfluenza were other notable viruses linked to pneumonia The research has important implications for antimicrobial resistance, because many children with viral infections could be wrongly prescribed antibiotics.