# 5980
We’ve another study that – despite returning somewhat mixed results – once again suggests the importance of maintaining good `flu hygiene’ during cold & flu season.
During the 2007-2008 flu season 10 Pittsburg elementary schools (grades K- 5) took part in a study where half of the schools served as controls, and half (5) were selected as `intervention’ schools.
Children in the intervention schools watched a special video on flu prevention, and were introduced to the `WHACK the Flu’ concepts.
WHACK stood for:
(W)ash or sanitize your hands often;
(H)ome is where you stay when you are sick;
(A)void touching your eyes, nose, and mouth;
(C)over your coughs and sneezes; and
(K)eep your distance from sick people.
This message was reinforced continually over the study period, and hand sanitizer dispensers were installed in each classroom and in major common areas of the intervention schools.
The goal was to encourage a minimum of 4 uses a day; upon arrival, before and after lunch, and prior to departure. Students were also encouraged to wash their hands and/or use the hand sanitizer as needed during the day.
Teachers were surveyed during the year regarding compliance rates among the students. Parents of students who were absent for more than one day received a phone call, and those who reported their child to have an ILI (influenza-like-Illness) received a home health visit where nasal swabs were obtained and tested for both influenza A & B.
The bottom line: at the intervention schools total student absences were reduced by 26% and lab confirmed influenza A infections were reduced by 52%.
Curiously, rates of influenza B were not reduced in this study, although the reasons why are less than clear. In their discussion, the authors suggest several possible reasons, including:
The observation of no effect on influenza B could be attributed to differences in the basic biology and epidemiology of influenza B compared with A or to the fact that influenza B infections occurred late in the season, after compliance with the intervention possibly had waned.
A quick Google search returned a pdf of the full study online at this link.
Below you’ll find some excerpts from the abstract which may be read at the following link:
Pediatr Infect Dis J. 2011 Nov;30(11):921-6.
Reduction in the incidence of influenza A but not influenza B associated with use of hand sanitizer and cough hygiene in schools: a randomized controlled trial.
Stebbins S, Cummings DA, Stark JH, Vukotich C, Mitruka K, Thompson W, Rinaldo C, Roth L, Wagner M, Wisniewski SR, Dato V, Eng H, Burke DS.
(EXCERPT)
RESULTS:
A total of 3360 children participated in this study. Using reverse-transcriptase polymerase chain reaction, 54 cases of influenza A and 50 cases of influenza B were detected. We found no significant effect of the intervention on the primary study outcome of all laboratory-confirmed influenza cases (incidence rate ratio [IRR]: 0.81; 95% confidence interval [CI]: 0.54, 1.23). However, we did find statistically significant differences in protocol-specified ancillary outcomes.
Children in intervention schools had significantly fewer laboratory-confirmed influenza A infections than children in control schools, with an adjusted IRR of 0.48 (95% CI: 0.26, 0.87). Total absent episodes were also significantly lower among the intervention group than among the control group; adjusted IRR 0.74 (95% CI: 0.56, 0.97).
CONCLUSIONS:
NPIs (respiratory hygiene education and the regular use of hand sanitizer) did not reduce total laboratory-confirmed influenza. However, the interventions did reduce school total absence episodes by 26% and laboratory-confirmed influenza A infections by 52%. Our results suggest that NPIs can be an important adjunct to influenza vaccination programs to reduce the number of influenza A infections among children.
In the full paper, the authors conclude:
This study demonstrated that a set of NPIs can be implemented successfully on a large scale within urban schools to reduce absenteeism and the incidence of influenza A.
Furthermore, the results provide support for currently recommended respiratory hygiene behaviors during seasonal and pandemic influenza outbreaks and should be included as part of an overall prevention strategy to reduce the burden of influenza among school-aged children.
While useful interventions during any flu season, these techniques are even more important during an outbreak of a novel virus – such as we saw in 2009.
Since vaccines typically take months to develop and even longer to deploy, simple, easy to implement NPIs (Non-pharmaceutical Interventions) such as these – while not a panacea - will undoubtedly form an important part of our initial response to any influenza epidemic.
