Vaccine topics discussed at ACIP meeting

Abstract

The following article covers vaccine topics discussed at the June 2012 Advisory Committee on Immunization Practices (ACIP) meeting. The article "ACIP meeting: Latest vaccine topics reviewed" on page 52 provides more information about this meeting. According to information presented at the meeting, Merck's hepatitis A vaccine Vaqta will be unavailable until mid-2012; however, production and supply of GlaxoSmithKline's adult hepatitis A vaccine (Havrix) and hepatitis A/hepatitis B combination vaccine (Twinrix) are sufficient to meet demand for routine adult usage. Sanofi Pasteur's Pentacel (tetanus, diphtheria, and pertussis [Tdap]; polio; and Haemophilus inBuenza type b [Hib]) and Daptacel (Tdap) are still on backorder; Merck's varicella virus vaccine Varivax is also backordered. In addition, it is anticipated that Merck's measles-mumpsrubella-varicella (MMRV) vaccine ProQuad will return to the market in October, and the backorder for its herpes zoster vaccine Zostavax has been resolved. Four meningococcal vaccines are now on the market: one polysaccharide (MPSV4 [Menomune—Sanofi Pasteur]), two conjugated quadrivalent (Menactra—Sanofi Pasteur and Menveo—Novartis), and a new combination of meningococcal groups C and Y and Hib-tetanus toxoid conjugate (MenHibrix—GlaxoSmithKline). This novel combination was approved by FDA in mid-June and is indicated in infants at age 2 months, 4 months, 6 months, and 12 months. ACIP has not recommended routine infant immunizations in the past due to the low incidence of disease in infants. Because the vaccine was approved shortly before the most recent ACIP meeting, the vaccine will be discussed at the group's October meeting. The 2010 Adult Vaccination Coverage schedule for patients 19 years to 64 years was recently published in CDC's Morbidity and Mortality Weekly Report. The report covers vaccines for Tdap, herpes zoster, human papillomavirus (HPV), and pneumococcal. Compared with 2009, there were only slight increases for Tdap (8.2% + 1.6%), zoster (14.4% + 4.4%), and HPV for women (20.7% + 3.6%), with the other vaccination rates remaining unchanged. The group concluded that all vaccination coverage remains low (far below 2020 targets). The improvement from 2009 was minimal, and racial and ethnic disparities remain. The inaugural National Adult Immunization Summit was held in conjunction with the National Influenza Vaccine Summit on May 15–17. The focus was increasing immunization rates in adults and reducing the burden of vaccine-preventable diseases. Major themes included improving communications and registries, decreasing policy and legal barriers for all providers, evaluating means to increase education of and incentivize providers, decreasing complexity of ACIP schedules, and engaging and encouraging immunization champions and leadership. The last time HPV was discussed by ACIP was October 2011, when the vaccine was approved for males. The National Immunization Survey for 2010 reported female coverage of the HPV vaccine to be 48.7% for one or more doses and 32% for all three doses. Data from eight Sentinel Immunization Information Systems sites funded by CDC showed only a slight increase in female coverage rates during the last 3 years. Only about 10% of males have received the HPV vaccine. Data on the impact of the HPV vaccine are currently being collected. One survey showed that the prevalence of anogenital warts in females aged 15 years to 19 years has decreased, whereas all other age groups increased. In addition, postlicensure monitoring for safety showed that the vaccine is safe but syncope remains a common problem. Currently, few trials are under way to evaluate the vaccine's efficacy with a decrease in the number of doses of vaccine needed. The last rubella pandemic was 1964–65 with 12.5 million cases in the United States. Following the development of the MMR vaccine, rubella was declared eliminated in 2004. An average of nine cases continue to occur each year, mostly in individuals older than 15 years, with onethird born in the United States. A total of 111,888 worldwide cases of congenital rubella syndrome (CRS) were reported in 2008. Six cases of CRS have been reported in the United States since 2005. Because wild measles has mostly disappeared from the American population, immunoglobulin levels of antibody against measles are also decreasing. The amount of antibody donated by people with previous MMR vaccination is lower that following natural disease. The recommended dose of intramuscular (I.M.) immunoglobulin for measles prophylaxis is 0.25 mL/kg (maximal dose is 15 mL). This dose is not adequate for measles prevention in most people. Doubling the dose would still give only minimal antibody concentrations; therefore, I.V. immunoglobulin may be needed to obtain an adequate dose. I.M. immunoglobulin is difficult to obtain because of supply issues. Discussion will continue. The ACIP working group has proposed policy changes for the MMR vaccine, including changing the definition of confirmation of disease and testing requirements, vaccination of patients with HIV, vaccination of household contacts of immunocompromised patients, and permissive use of a third dose in outbreaks. These ideas will be discussed further at future meetings. The next ACIP meeting is October 24–25 in Atlanta.