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41st National Immunization Conference

Kansas City, Missouri / March 5-8, 2007

According to Dr. Kristin Nichol, Professor of Medicine, University of Minnesota, Minneapolis, because 99% of all vaccine-preventable diseases (VPDs) are in adults vs. 1% in children, there is an urgent need to improve adult immunization coverage. VPDs are also responsible for substantially more deaths each year than either colorectal, breast or prostate cancer. “We have a long way to go if we want to control disease burden due to VPDs in adults,” Dr. Nichol told the audience. Hence, new strategies are called for to increase adult vaccination coverage, starting with traditional health care providers themselves.

Physician and Patient Education

Speakers here agreed that physicians are often unaware of both the need for and the availability of adult vaccines and improved physician education is paramount in this regard. “We also need to practice what we preach,” Dr. Nichol admitted: immunization rates among physicians for the influenza vaccine, for example, are notoriously low at <40%.

Patients are also unaware of what vaccines are available to them and why they might benefit from vaccination, Dr. Nichol noted. Concerns about vaccine safety are still among the key reasons why adults refuse vaccination for both their children and themselves: once again, education is critical to address these concerns. “What we first and foremost need is to make sure providers recommend vaccination when they encounter patients,” Dr. Nichol stressed. One study, for example, showed that the vaccination rate was only about 20% when physicians did not recommend the influenza vaccine vs. approximately 80% when they did.

Physicians also need to resort to simple strategies such as chart reminders in order to trigger a discussion about vaccination as patients present. Probably the most effective of system-based approaches is the use of a standing orders program. In one group of elderly patients, a standing orders program increased the proportion of adults who received the influenza vaccine to over 95% compared with 22% when physician reminders were used and 12% with physician education.

Non-traditional Outreach Strategies

However, not everyone has a primary care provider, as Dr. Nichol reminded delegates; vaccination programs in non-traditional settings have much to offer. Here, people could be encouraged to seek vaccination in non-traditional settings, such as the workplace, pharmacies, community centres, sexually transmitted disease (STD) clinics, local health departments, county jails, churches and daycare centres.

Several speakers detailed their successes by approaching special needs groups with innovative outreach strategies. One such approach deployed by the New York State Department of Health (NYSDOH) targets high-risk adolescents and adults for vaccination against hepatitis A and B. Since 1995, the NYSDOH has been actively promoting vaccination against hepatitis, primarily in STD clinics, but now partners with local health departments statewide, along with county jails and at migrant sites. “The program provides outreach education and technical assistance to all providers,” noted Dr. Debra Blog, NYSDOH, Albany, “and we distribute vaccines to all participating sites at no cost.” In 2005, the team delivered over 18,000 doses of the hepatitis vaccine across all immunization sites and they are currently looking to expand their partnerships with substance abuse and addiction treatment centres.

Another very vulnerable segment of the population whose vaccination coverage needs considerable improvement are migrant and seasonal farm workers. As pointed out by Valerie Polletta, NYSDOH, over 80% of the state’s migrant and seasonal farm workers are foreign-born and the great majority neither speak nor read English. “They also have very demanding jobs, live in rural communities where there is no public transport and have no health care coverage, so it is very difficult for them to access care,” Ms. Polletta noted. The NYSDOH recognizes that it is precisely this group for whom inadequate housing conditions, poor sanitation and hazardous occupations makes the uptake of vaccines that much more important. Consequently, the NYSDOH has made every effort to tailor vaccination clinics to workers’ schedules and to elicit help from other members in their community in order to gain the workers’ trust. They also bring the vaccines to the workers through the use of mobile clinics set up at farms where they work and reside; at local churches; at health fairs; in daycare centres where workers take their children; and through any other local venue that makes it easy for workers to get vaccinated. “Migrant and seasonal workers are a vulnerable and hard-to-reach population and immunization is a hard message to sell,” Ms. Polletta acknowledged, “but it is not impossible and we are reaching out to growers too because employers can help us reach their employees.”

Another special group of patients who physicians seem to be largely hesitant to vaccinate are pregnant women. As discussed by nurse practitioner Mary Beth Koslap-Petraco, MS, Suffolk County Department of Health Services, Hauppauge, New York, nursing staff working within the county’s department of health services initially developed a teaching program for women attending prenatal clinics across the county. Nurses assessed each woman’s immunization status and each was then offered immunization along with vaccine-specific education. Standing orders were issued for immunization to follow and vaccines given as indicated; since then, uptake of various vaccines, including hepatitis A and B, tetanus and diphtheria, has been brisk. “Standing orders work because they empower the nurses to own vaccines and use them,” Ms. Koslap-Petraco observed. “This program has had a significant impact on our population in getting vaccines into them and it could be used as a model for the private provider community as well.”

Newest Vaccine for Adults

The newest vaccine now licensed for use in adults age 60 and older is the herpes zoster vaccine. Available since May 2006, the vaccine contains the same strain of live, attenuated varicella virus used in the varicella vaccine for children but it is significantly more potent. As several speakers indicated, widespread uptake of the herpes zoster vaccine could significantly reduce the burden of illness caused by reactivation of the varicella virus in the form of herpes zoster as well as its complication, post-herpetic neuralgia (PHN).

As results from the SPS (Shingles Prevention Study) showed, the incidence of PHN was two-thirds less in vaccine recipients than in placebo controls, while the incidence of herpes zoster was approximately half that of the control group. “The efficacy of the vaccine for the prevention of herpes zoster does decline from the age of 70 onwards but the vaccine still modifies the severity of illness if you get it after you are 70,” noted Dr. Jane Seward, Acting Deputy Director, Division of Viral Diseases, Centers for Disease Control, Atlanta, Georgia.

Importantly, from a public perspective, no case of herpes zoster has been linked to the vaccine virus and no pattern emerged during the SPS suggesting a causal link to serious adverse events. As Dr. Seward noted, the vaccine is not indicated for the treatment of herpes zoster or PHN, only for their prevention in adults 60 years of age and older whether or not they have had a prior episode of herpes zoster. Concluded Dr. Aisha Jumann, acting team leader, Varicella and Herpes Zoster Group, Centers for Disease Control, “Herpes zoster causes considerable morbidity in elderly persons and its complications may now be prevented. Patients [60 years of age and older] should be offered this vaccine.”