The CDC's Advisory Committee on Immunization Practices, or ACIP, made two provisional recommendations during its June 22-23 meeting in Atlanta that could significantly alter the way family physicians approach tetanus, diphtheria and acellular pertussis, or Tdap, vaccination and seasonal influenza vaccination in certain patient groups.
In particular, the ACIP voted to recommend(1 page PDF) that pregnant women who have never received the Tdap vaccine should be immunized during their second trimester (after 20 weeks gestation) or during their third trimester rather than in the immediate postpartum period. The committee also voted to recommend that an allergy to eggs be changed from a contraindication to a precaution for flu vaccine.
Increased rates of pertussis led to the new recommendation for Tdap. More than 9,100 cases of pertussis were reported in California(www.cdph.ca.gov) last year, including more than 800 hospitalizations and nine infant deaths.
"The committee believes that the mother will produce antibodies against pertussis that she'll pass to the newborn," said Doug Campos-Outcalt, M.D., M.P.A., who served as the AAFP's liaison to the ACIP through the committee's June 22-23 meeting and who will begin a four-year term as a member of the ACIP on July 1.
Campos-Outcalt, who also is associate head of the department of family and community medicine at the University of Arizona College of Medicine, Phoenix, said newborns are the highest-risk group for complications and death from pertussis. Children do not begin the diphtheria, tetanus, and pertussis, or DTaP, vaccine series until they are 2 months old, and there is little protective antibody in infants immunized with DTaP until they are 4 months of age or older.
Campos-Outcalt said new safety and efficacy data presented during the ACIP meeting supported the use of Tdap during pregnancy, and preliminary data indicate that vaccinating a mother does not interfere with a child's response to the DTaP vaccine.
The ACIP's provisional recommendation specifies the following stipulations for Tdap:
- if a pregnant woman is up-to-date on tetanus and diphtheria toxoids, or Td, vaccine but has never had Tdap, she should receive Tdap during her second or third trimester, and
- if a woman's history of Td vaccination is unknown, or she never has received it, she should be brought up-to-date with series of immunizations, including one dose of Tdap.
The ACIP also voted to endorse a recommendation for use of tetravalent inactivated flu vaccine, or TIV, in patients who are allergic to eggs but who have not experienced anaphylaxis, moving egg allergy from a contraindication to a precaution.
"Evidence is pretty good that virtually everyone who reports egg allergy but hasn't actually had an anaphylactic reaction to flu vaccine will do just fine," Campos-Outcalt said. "The flu vaccine has such low concentration of egg protein, and most people outgrow egg allergies from childhood. It's really pretty safe to give these people the flu vaccine. There are some people doing skin testing with vaccine or giving vaccine at one-tenth of a dose to see if the patient reacts, and that's not necessary."
The recommendation is as follows:
- for patients with a history of egg allergy without anaphylaxis, there is no need to divide doses or perform skin testing before vaccination;
- there will be no need to confirm the levels of ovalbumin in the 2011-12 flu vaccine because all products will contain less than 0.6 micrograms per dose;
- patients with egg allergy should be observed for 30 minutes after vaccination; and
- vaccine providers should be equipped and trained to handle anaphylactic emergencies.
The change applies only to TIV. Live, attenuated influenza vaccine, or LAIV, should not be used in patients who report an egg allergy.
The ACIP also voted to recommend a two-dose series of quadrivalent meningococcal conjugate vaccine, or MCV4, for children in certain high-risk groups starting at age 9 months.
The ACIP already had a universal meningococcal vaccine recommendation for adolescents(5 page PDF) ages 11-12 years, as well as recommendations for high-risk children starting at age 2. The provisional recommendation would lower the recommendation to 9 months for children with specific complement deficiencies and for those traveling to or living in areas where meningococcal disease is endemic. The MCV4 recommendation for children with asplenia, however, remains at 2 years.
Finally, the ACIP discussed the FDA's expansion of the license for herpes zoster vaccine, which is marketed by Merck & Co. Inc. as Zostavax, from including only patients ages 60 and older to also include those 50-59 years.
Merck has had difficulty maintaining a steady supply of the vaccine, and Campos-Outcalt said there also are questions about the duration of protection that the vaccine offers. Therefore, the ACIP did not vote on whether to recommend the vaccine in patients ages 50-59, and the committee's recommendation(4 page PDF) for those 60 and older remains in place.
"The vaccine is not in abundant supply, so you don't want to use it in age groups where you won't get as much benefit," Campos-Outcalt said. "The highest incidence of zoster is in people over age 60, and particularly over age 70 and 80. If you give the vaccine to people age 50, you're giving it to the lowest-risk group, and you don't know how long the protection from the vaccine is going to last."
Campos-Outcalt said the committee may address the issue again when supplies increase and more data are available regarding duration of protection.
CDC: Pertussis (Whooping Cough) (www.cdc.gov)