According to the CDC, as of Jan. 10, more than 2,600 hospitalizations for influenza(www.cdc.gov) had been reported to the agency for this flu season, and there have been 10 confirmed pediatric deaths.
Parker Small Jr., M.D.
Despite recommendations to vaccinate all children and adults (with few exceptions) and the widespread availability of vaccine at physician offices, county health clinics, pharmacies, workplaces and even grocery stores, some people still aren't getting the message about the importance of getting immunized.
So, what can we do better, or differently, to protect our communities?
Transmission and mathematical modeling studies have shown that immunizing schoolchildren against influenza will not only protect them, it also will protect their larger communities. For example, evaluation of Japan's nationwide, school-located influenza vaccination (SLIV) program(www.nejm.org) determined that one life was saved for every 420 children immunized. One modeling study(courses.washington.edu) suggested that immunizing 20 percent of schoolchildren would protect the elderly better than immunizing 90 percent of people ages 65 and older. Another study(www.crd.york.ac.uk) suggested that immunizing 70 percent of children might protect the entire community.
This makes sense when you stop and think about who interacts with whom, and where and when that interaction takes place. Schoolchildren are within the 6-foot flu-spread area with perhaps 50 fellow students each day before returning home to close family contacts. Few adults have as many opportunities to get and give flu. The reality is that schools are virus-exchange systems, and children are super-spreaders.
This is not just because of behaviors. Children shed more virus, and they do so for a longer period than adults when infected for the first time. This is because cross-protective, cell-mediated immunity induced by the first flu infection speeds recovery in subsequent flu infections.
The concept of immunizing children in school is so powerful that the United Kingdom has decided to launch a nationwide SLIV program(www.gov.uk) in 2014.
Since 2006, Alachua County in north central Florida has developed one of the most successful SLIV programs in the nation. The county immunizes more than 50 percent of its public and private schoolchildren at school and another 10 percent in physicians' offices. Incidentally, the number of children immunized in physicians' offices has increased as the SLIV program has developed. The program has been recognized by the CDC and the AMA. The Institute of Medicine recognized the program as a model for integrating primary care and public health(www.nationalacademies.org).
The initial step in creating an SLIV program is having leaders in the school system, the health department and the medical community -- including family physicians -- commit to it.
The next step is to identify the vaccine to be used and the personnel who will administer the immunizations. Our experience in Florida is that using live attenuated influenza vaccine (LAIV; FluMist) in school and referring children who are ineligible for LAIV -- mostly patients with asthma -- to their physicians promotes communication and cooperation between community physicians and the SLIV program.
Clinical studies comparing LAIV and inactivated influenza vaccine (IIV)(www.thelancet.com) show LAIV to provide superior protection in young children. The IgA antibody LAIV induces stops nasal and tracheal infection and, therefore, spread of influenza. The IgG response induced by IIV does not stop nasal or tracheal infection and so does not stop the spread of influenza. IIV does prevent viral pneumonia, and it reduces severity and duration of illness.
Who should administer the actual immunization varies and depends on community resources and needs. In many areas of the country, private companies exist that will immunize all children for free and recover the cost, plus a profit, by billing private insurance or Medicaid. If community resources can be mobilized to administer the vaccine, the surplus funds that will be generated by the SLIV program can be retained locally.
The major challenge in SLIV programs is obtaining parental consent. This requires significant school and community involvement. Without such involvement, only 15 percent to 25 percent of parents likely will provide consent. To achieve higher rates and the associated community protection, widespread school and community involvement is necessary.
A key issue is requesting return of a form that indicates whether the parent consents or refuses immunization. Having a form allows a staff person to follow up with parents who do not respond. It is highly likely that additional community involvement will be required to obtain optimal participation, but this will vary depending on the community.
In Alachua County, we have had no significant flu outbreaks in the past few years, while most other nearby communities have been hit hard. We're in the process of quantitating the protection provided by our SLIV program.
What is clear is that your community can protect itself from flu outbreaks, thereby reducing suffering and saving lives and money. As with most successful programs, the most important requirement is having capable community leaders, including primary care physicians.
Parker Small Jr., M.D., is a member of the Emerging Pathogens Institute and professor emeritus in the departments of Pediatrics and Pathology, Immunology, and Laboratory Medicine at the University of Florida College of Medicine in Gainesville.