Interventions for the interruption or reduction of the spread of respiratory viruses

Oct 17 2007

If SARS makes a comeback or a serious epidemic of flu becomes a reality, children could become an important focus in fighting back against these deadly viruses, according to a new review of recent studies.

Structured hygiene routines aimed at younger children might be the most effective way to stem an epidemic respiratory virus, say Tom Jefferson, M.D. and colleagues.

Younger children tend to have longer-lasting infections, more social contacts and less-than-perfect hygiene, making them “portals of infection into the household,” Jefferson said.

Relatively simple measures such as hand washing and consistent use of protective gowns, gloves and surgical masks are among the best ways to slow the march of a respiratory virus, the researchers concluded after analyzing 51 studies.

However, it might be difficult to make these efforts part of a long-term and routine strategy “without the threat of a looming epidemic,” they write.

Their review appears in the latest issue of The Cochrane Library , a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

Other ways to control the spread of respiratory viruses among children, such as closing schools, “are largely unproven and untested,” said Jennifer Nuzzo, an epidemic researcher at the Center for Biosecurity, University of Pittsburgh Medical Center.

“It's likely that the effectiveness of school closures would depend on what respiratory disease is present, how early the measure is applied and for how long and whether or not kids are prevented from mixing elsewhere,” Nuzzo said.

The jury is still out on whether measures that are more elaborate add much beyond basic hygiene strategies. Expensive and uncomfortable filtration masks might be more effective than paper masks, but the evidence is limited, the Cochrane researchers found. So far, it is also unclear whether the use of antiseptics and virucides has any benefits beyond those offered by frequent regular hand washing.

The studies in the reviews took place over four decades in schools, soldier barracks, slums and daycare centers. However, “we were able to identify few studies from low-income countries, where the vast majority of the burden lies and where cheap interventions are so critical,” Jefferson said.

Jefferson T, et al. Interventions for the interruption or reduction of the spread of respiratory viruses (Review). Cochrane Database of Systematic Reviews, 2007, Issue 4.

The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions. Visit http://www.cochrane.org for more information.