H1N1 Vaccine Based on CDCs ACIP Meeting, July 29, 2009

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1 August 6, 2009 H1N1 Vaccine Based on CDCs ACIP Meeting, July 29, 2009 CDC s Advisory Committee on Immunization Practices (ACIP), a panel made up of medical and public health experts, met July 29, 2009, to make recommendations on who should receive the new H1N1 vaccine when it becomes available. What We Know: CDC is concerned that the new H1N1 flu virus could result in a particularly severe flu season this year. Vaccines are the best tool we have to prevent influenza. CDC hopes that people will start to go out and get vaccinated against seasonal influenza as soon as vaccines become available at their doctor s offices and in their communities (this may be as early as August for some). The seasonal flu vaccine is unlikely to provide protection against novel H1N1 influenza. A novel H1N1 vaccine is currently in production and may be ready for the public in the fall. The novel H1N1 vaccine is not intended to replace the seasonal flu vaccine it is intended to be used along-side seasonal flu vaccine. Some issues are still unknown, such as how severe the virus will be during the fall and winter months, the ACIP considered several factors, including: o current disease patterns, o populations most at-risk for severe illness based on current trends in illness, o hospitalizations and deaths, o how much vaccine is expected to be available, and the timing of vaccine availability. Targeted H1N1 Vaccine Groups The groups recommended to receive the novel H1N1 influenza vaccine include: Pregnant women o because they are at higher risk of complications and can potentially provide protection to infants who cannot be vaccinated; Household contacts and caregivers for children younger than 6 months of age o because younger infants are at higher risk of influenza-related complications and cannot be vaccinated. Vaccination of those in close

2 contact with infants less than 6 months old might help protect infants by cocooning them from the virus; Healthcare and emergency medical services personnel o because infections among healthcare workers have been reported and this can be a potential source of infection for vulnerable patients. Also, increased absenteeism in this population could reduce healthcare system capacity; All people from 6 months through 24 years of age o because we have seen many cases of novel H1N1 influenza in children and they are in close contact with each other in school and day care settings, which increases the likelihood of disease spread, and Children from 6 months through 18 years of age Young adults 19 through 24 years of age because we have seen many cases of novel H1N1 influenza in these healthy young adults and they often live, work, and study in close proximity, and they are a frequently mobile population; and, Persons aged 25 through 64 years who have health conditions associated with higher risk of medical complications from influenza. If Limited Vaccine Supply o CDC do not expect that there will be a shortage of novel H1N1 vaccine, but flu vaccine availability and demand can be unpredictable and there is some possibility that initially, the vaccine will be available in limited quantities. So, the ACIP also made recommendations regarding which people within the groups listed above should be prioritized if the vaccine is initially available in extremely limited quantities. For more information see the CDC press release CDC Advisors Make Recommendations for Use of Vaccine Against Novel H1N1. o Once the demand for vaccine for the prioritized groups has been met at the local level, programs and providers should also begin vaccinating everyone from the ages of 25 through 64 years. Current studies indicate that the risk for infection among persons age 65 or older is less than the risk for younger age groups. However, once vaccine demand among younger age groups has been met, programs and providers should offer vaccination to people 65 or older. o Priority Groups (the following receive vaccine before others): pregnant women, people who live with or care for children younger than 6 months of age,

3 health care and emergency services personnel with direct patient contact, children 6 months through 4 years of age, and children 5 through 18 years of age who have chronic medical conditions. Vaccine Manufacturing Novel H1N1 vaccine is being procured by the U.S. government from five (5) vaccine manufacturers of currently U.S.-licensed seasonal influenza vaccines inactivated subunit (4) and live, attenuated vaccines (1). Inactivated licensed novel H1N1 vaccine will be available in single-dose syringes, or in multi-dose vials. Live attenuated vaccine will be available in limited number in inhaler sprayers. Single-dose syringes will be thimerosal-free, which will address concerns about this additive, especially regarding pediatric and pregnant vaccine recipients (inhaler sprayer vaccine products will also be thimerosal-free). The availability of novel H1N1 vaccine is dependent on multiple factors including: o virus growth at commercial scale, o regulatory review, o availability of calibrated vaccine product potency assay reagents, o overall production capacity, o and availability to U.S. through HHS contracts. Vaccine Trials Some 3,000 people across the United States have volunteered to participate in fast-track clinical trials to assess the efficacy of a vaccine against the H1N1 swine flu virus, more than the estimated 2,800 needed. Researchers at eight trials sites in the United States are seeking healthy adults, ages 18 to 64 years; elderly volunteers 65 years of age and older; and children ages six months to 17 years. The Vaccine and Treatment Evaluation Units will conduct five initial trials to determine how much of the vaccine is necessary to stimulate an immune response, while other scientists will assess the safety of giving a normal seasonal flu shot with the new vaccine. Lab tests will be processed in real time, and results may be available as soon as early September. Vaccine Purchase and Allocation The government has purchased enough bulk ingredients to produce 195 million doses of H1N1 vaccine, and up to 100 million doses could be available this fall. The United States could have enough doses for its population by next March.

4 The vaccine will be made available for vaccinators at no cost. Syringes, needles, sharps containers and alcohol swabs will also be provided. Vaccine will be allocated across states proportional to population. State health departments (and a few separately funded cities) will direct their allocation to local health departments and other vaccination partners. Planning Assumptions Given uncertainty around the amount and timing of vaccine availability, state and local public health planners have been asked to plan for vaccine becoming available mid-october under the following scenarios: 40, 80, or 160 million doses becoming available from the 5 manufacturers (total) over approximately a one month period, followed by weekly amounts of 10, 20 or 30 million doses. At this point, the planning assumption is that the vaccine will require 15 µg of antigen for an immunizing dose, and that two doses spanning over 21 or more days will be needed for efficacy for most persons. Clinical trials will be conducted to determine which age groups, if any, require only one dose. The majority of vaccine will be packaged in multidose vials but enough preloaded syringes will be manufactured for young children and pregnant women. In addition, based on best available information to date, planners have been provided scenarios to serve as a basis for making venue-based plans to vaccinate specific populations. These populations include: o students and staff (all ages) associated with schools (K-12th grade) and children (age 6 months) and staff (all ages) in child care centers; o pregnant women, children 6 months 4 years of age, o new parents and household contacts of children <6 months of age, and non-elderly adults with medical conditions that increase the risk of complications of influenza, o and health care workers and emergency services personnel. Formal recommendations for the use of novel H1N1 vaccine will be made by the ACIP in August 2009 based on all available epidemiologic data to date. Vaccine Delivery System Many state health departments are partnering with private sector partners to ensure the novel H1N1 vaccine is delivered to as many recommended persons as rapidly as possible. Vaccine will thus be available in a combination of settings including public health organized vaccination clinics, and in private sector settings such as provider offices (e.g. pediatricians, family physicians, obstetricians, internists), retail settings, pharmacies, workplaces, and through community vaccinators. Private providers who wish to administer the novel H1N1 vaccine will need to enter into relationships with their public health department so that vaccine can be directed to them.

5 While providers will receive the vaccine at no charge, information on reimbursement for administration is needed. CDC asked AHIP (America s Health Insurance Plans) whether insurance plans would reimburse private providers for administration and received the following answer: Every year health plans contribute to the seasonal flu vaccination campaign in several ways: a) Health plans communicate directly with plan sponsors and members on the current ACIP recommendations and encourage immunization; they also provide information on where to get vaccinations, and who to contact with any questions; b) Just as health plans have provided extensive coverage for the administration of seasonal flu vaccines in the past, public health planners can make the assumption that health plans will provide reimbursement for the administration of a novel (A) H1N1 vaccine to their members by private sector providers in both traditional settings e.g., doctor s office, ambulatory clinics, health care facilities, and in non-traditional settings, where contracts with insurers have been established. Providers participating in novel H1N1 vaccination will be expected to administer vaccine in accordance with national recommendations for use of the vaccine. In addition, if administering vaccine during the early weeks, they will be expected to report weekly on the number of doses administered and the ages of persons who were vaccinated. Such data are critical for assessing early uptake and for adverse event monitoring as they provide a means of calculating adverse events rates. Monitoring Coverage, Safety, and Effectiveness Vaccine coverage will be monitored initially through weekly reports of doses administered, based on requirements set forth by CDC. Once the number of vaccinated persons is large enough to be detectable through population surveys, this information will be collected on an ongoing basis providing for monthly coverage estimates. The Vaccine Adverse Event Reporting System (VAERS), a national vaccine safety surveillance program co-sponsored by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration (FDA) collects an analyzes information from reports of adverse events following immunization and will serve as the foundation for safety monitoring. VAERS accepts reports from patients, providers, public health officials and others ( , ). Signals that are detected through VAERS will be tested using a network of managed care organizations representing approximately 3% of the U.S. population, the Vaccine Safety Datalink (VSD). Vaccination information as well as individual outcome data are available though this network both to test signals on an ongoing basis and to monitor pre-specified adverse events. Additional strategies are being developed to actively monitor Guillain Barre Syndrome (GBS) incidence during the novel HINI influenza vaccination season with networks of providers set up for active case-finding. CDC will utilize at least two primary means to assess vaccine effectiveness:

6 o the first will assess vaccine effectiveness for prevention of laboratory confirmed medically attended influenza at 4 community based sites; o the second will assess vaccine effectiveness for prevention of influenza hospitalizations diagnosed by provider-ordered clinically available tests at 10 sites nationwide through the Emerging Infections Program. Additional assessments of influenza vaccine effectiveness will be conducted by the US Department of Defense which has the ability to conduct timely assessments of vaccine effectiveness in their active duty populations. Seasonal Vaccination Seasonal vaccine will be available beginning in August or September The seasonal influenza vaccine is expected to be available earlier than the novel H1N1 vaccine, but the availability of the two vaccines is expected to overlap. The process for ordering seasonal vaccine is unchanged from previous years. Variables: Target groups may change How much vaccine will be allocated for Kern County of Kern Vaccine might be ineffective Vaccine might have side-effects H1N1 morbidity and mortality may increase, decrease, or remain the same H1N1 resistance to antiviral meds