- Tdap vaccine is recommended for women during every pregnancy, any time during the pregnancy, but ideally between 27 through 36 weeks gestation
- Meningococcal vaccine is recommended for high risk infants down to age 2 months using the HibMenCY-TT vaccine.
- VFC resolution was modified to include quadravalent influenza vaccines which will be available as Q/LAIV and QIV next season
- Upcoming publications: updated Meningococcal and MMR recommendations will be published by the end of this year. The 2013 pediatric schedule combining ages 0-6 and 7-18 years and the 2013 adult schedule were approved.
Tdap Vaccine in Pregnant Women
Even though the nation is currently experiencing a pertussis outbreak with the highest incidence seen since 1959, so far, with current recommendations for Tdap immunization during pregnancy, only 2.6% of women have been vaccinated. The majority of deaths from pertussis occur in infants under age 3 months, when the infant is too young to be protected by direct immunization. Cocooning strategies have had mixed success. Protective pertussis antibodies are passed to the fetus transplacentally when the pregnant mother is vaccinated during pregnancy. Newborns from vaccinated mothers have higher antibody titers than those of unvaccinated mothers. Some blunting of the infant’s response to DTaP vaccine may be seen with maternal immunization, but this appears to resolve by the third DTaP dose. Maternal antibody response peaks one month after receipt of vaccine and then declines dramatically by one year, necessitating vaccination in subsequent pregnancies. Experience with tetanus toxoid vaccine suggests no widespread adverse events to mother and infant when vaccinated during pregnancy and VAERS data on Tdap during pregnancy show that the risk of administration is small. Data is limited on the safety of immunization with multiple pregnancies, but ACIP concluded that the benefits of immunization at each pregnancy outweighed the theoretical risk of adverse events.
ACIP recommends that providers of prenatal care implement a Tdap immunization program for all pregnant women. Health care personnel should administer a dose of Tdap during each and every pregnancy irrespective of the patient’s prior history of receiving Tdap. In order to maximize the maternal antibody response and passive antibody transfer to the infant, the ideal time to administer the vaccine is later in the pregnancy near the time of delivery, but not too late and risk missing administering the vaccine, developing maternal antibodies and passing the antibodies to the fetus prior to delivery (27-36 weeks gestation). Tdap is safe to administer in all trimesters. Pregnant women should receive the vaccine earlier in their pregnancy if it is felt they may not be available for vaccination at the optimal time. If not administered during pregnancy, Tdap should be administered immediately post-partum.
High incidence of pertussis in the 7-10 year age group has raised concerns about a greater risk of waning immunity after the acellular pertussis (aP) vaccine than with the whole-cell pertussis (wP) vaccine. Effectiveness of Tdap in adolescents is estimated at 70%, but the population studied with this level of effectiveness received the wP rather than aP vaccine in their infant series. Studies are underway to understand the impact of infant aP receipt on effectiveness of adolescent Tdap. Revaccination of adults will be considered in the February 2013 meeting.
Meningococcal Vaccine for Infants and Toddlers
HibMenCY-TT (MenHibrix) has been approved by the FDA for use in infants down to 2 months of age to be used in a 4 dose series at 2, 4, 6, and 12-15 months of age. The first dose may be given as early as 6 weeks of age and the last dose may be given as late as 18 months of age. The ACIP reviewed studies showing MenHibrix to be safe and effective in providing antibody against Haemophilus Influenza, and meningococcal groups C and Y, with persistence of antibody until age 6 years. MenHibrix was found not to interfere with routine infant vaccines – PCV7, DTaP-Hep B-IPV, MMR, or Varicella. Certain children are at high risk for the development of meningococcal disease. Those with a C3, properidin, factor D or late complement component deficiency are 7,000-10,000 times more likely to contract N. meningiditis than the general population. Currently, MenACWY-D (Menactra) is recommended for a two dose series starting at age 9 months for high risk infants.
The ACIP recommends that those infants at increased risk (including those with recognized persistent complement pathway deficiencies, who have functional or anatomic asplenia, including sickle cell disease) should be vaccinated with 4 doses of HibMenCY-TT, starting at age 2 months or with 2 doses of MenACWY-D starting at age 9 months. HibMenCY-TT is not recommended in infants who are traveling to the meningitis belt or the Haj where the predominant meningococcal is types are A and W-135 which are not in the HibMenCY-TT vaccine. MenACWY-D is not recommended for infants with asplenia until age 2 years when the PCV13 series has been completed due to pneumococcal interference. HibMenCY-TT may be administered as a Hib vaccine. ACIP also clarified that HIV is not a valid high-risk indication for immunization with meningococcal vaccine ages 2 months to 9 years of age.
ACIP will vote on whether HibMenCY should be used as a Hib vaccine for VFC in February 2013.
The abbreviation nomenclature for influenza vaccine has been modified. TIV (trivalent influenza vaccine) is replaced by IIV (inactivated influenza vaccine). The VFC influenza resolution was modified to include quadravalent vaccines which will be available as Q/LAIV and QIV next season.
Q/LAIV was approved in February 2012. MedImmune does not expect that adding the additional B strain to the vaccine will impact vaccine supply or timing. During a vaccine shortage, it is possible that less people overall will be vaccinated due to producing a vaccine with four strains rather than three strains. The safety profiles of Q/LAIV and T/LAIV were comparable although a statistically higher rate of fever was reported in Q/LAIV recipients after the first dose. Medimmune will transition all of its T/LAIV to Q/LAIV next season with comparable pricing to the T/LAIV.
Studies have been conducted on Sanofi’s QIV product. Safety and immunogenicity were comparable to TIV for three strains with superior immunogenicity to the fourth strain. If approved, Sanofi will distribute a limited supply of QIV in 2013 as approval would occur in mid-2013 after the pre-book season. In addition, as the product is not licensed, sales representatives will not be able to promote the product and reimbursement may not be in place. Sanofi will gradually transition from its TIV to QIV product. Some premium for the new product is anticipated.
GSK has submitted QIV versions of its licensed vaccines Fluarix and FluLaval for approval. Application for Fluarix was submitted early in 2012. Safety and immunogenicity were comparable to TIV for three strains with superior immunogenicity to added B strain. QIV Fluarix licensure is anticipated at the end of 2012 and FluLaval licensure is anticipated in 2013. QIV capacity will be up to 15 million doses for the 2013-2014 season and up to 75 million doses for the 2014-15 season. TIV will be available in the 2013-14 season. GSK will transition gradually to the QIV product, and states that pricing has not yet been established.
Novartis presented data on a cell culture inactivated influenza vaccine (ccIIV). The vaccine was demonstrated to be safe and immunogenic and demonstrated efficacy of 83% against vaccine strains and 70% against all circulating strains. A quadrivalent product is in development. There is no indication for children under age three years. Novartis has an adjuvanted vaccine developed for that age group.
Updated Meningococcal and MMR recommendations will be published by the end of this year. The 2013 pediatric schedule combining ages 0-6 and 7-18 years and the 2013 adult schedule were approved.
If you have any questions regarding immunization, feel free to contact Tamara Sheffield, MD, MPA, MPH, Medical Director, Community Health and Prevention, Intermountain Healthcare, at (801) 442-3946.