Hand-washing, mask-wearing may limit transmission of pandemic flu

Practicing non-pharmaceutical interventions (NPIs) such as hand-washing and mouth covering may help limit the transmission of the pandemic flu, but more research on these measures is critical according to a new study appearing in the May issue of AJIC: American Journal of Infection Control, the official publication of the Association for Professionals in Infection Control and Epidemiology, Inc. (APIC). The study presents findings which show that although significant knowledge was gained regarding NPIs and transmission of pandemic flu in Centers for Disease Control and Prevention (CDC)-funded studies, key concerns and gaps in the research related to the acceptability and protective efficacy of these measures remain.

NPIs include measures other than vaccines and antiviral treatments that reduce the harm and spread of disease. NPIs can be implemented at the border level, the community level, or the individual level. Examples of individual actions include frequent hand washing with soap, using alcohol-based hand sanitizer, covering sneezes/coughs and wearing a mask. Social distancing policies (border and community level) involve things like closing schools, working from home or restricting public gatherings. These practices are specifically geared to limit the spread of the disease from person to person.

"The recent influenza A (H1N1) pandemic may provide us with an opportunity to address many research gaps and ultimately create a broad, comprehensive strategy for pandemic mitigation," according to Allison E. Aiello, PhD, MS,. Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI. "However, the emergence of this pandemic in 2009 demonstrated that there are still more questions than answers.

More research is urgently needed, especially in light of the potential for mutations in influenza A (H1N1). If mutations do occur, or if new pandemic strains emerge in the future, NPIs likely will play a crucial role in mitigating the spread of infection when vaccines are unable to provide sufficient protection."

Research project investigators and contributors to this analysis identified many gaps among CDC-funded projects falling into two main categories: (1) behavioral and social sciences and (2) biological and technological sciences. The authors conclude that "taken together, the data provide some evidence that face masks, hand hygiene, cough etiquette, reduced crowding, and school closures are effective in reducing the spread of influenza. Nonetheless, further studies with larger sample sizes, common methodologies to allow pooling of data, and study durations that cover multiple influenza seasons are needed. In addition, further laboratory studies are needed to address the relative contribution of transmission modalities (i.e., small vs. large respiratory droplets and contact transmission). Finally, research should include assessments of psychosocial and cultural factors that shape compliance with NPIs, to explore why certain groups accept NPIs while others do not, and whether barriers to compliance are lifted during a global pandemic."