ACIP Now Recommends Tdap Vaccine at Age 65 Years and Older

The Centers for Disease Control and Prevention's (CDC's) Advisory Committee in Immunization Practices (ACIP) has recommended a booster dose of the tetanus, diphtheria, and pertussis (Tdap) vaccine in people between the ages of 11 and 64 years and in those older than 65 years if they come in close contact with infants.

In 2005, ACIP voted to recommend routine use of a single dose of Tdap for adults 19 to 64 years of age to replace the next booster dose of tetanus and diphtheria toxoids vaccine (Td). ACIP also recommended Tdap for adults who have close contact with infants younger than 12 months of age.

Tdap Safe in Adults Aged 65 Years and Older

Yesterday, ACIP built on those recommendations by voting that Tdap can replace Td in adults aged 65 years and older in those who have not previously received Tdap. In addition, adults aged 65 years or older who anticipate contact with children aged 12 months or younger should also be vaccinated to protect both themselves and the infant.

According to Jennifer L. Liang, DVM, from the ACIP Pertussis Working Group, who presented on this issue, Tdap vaccine is not currently licensed for use in adults aged 65 years or older; however, data from the Vaccine Adverse Event Reporting System suggest that the "safety profile of Tdap vaccine in these adults is as safe as the Td vaccine."

Language on Tdap Interval Removed

The committee also voted that uncertainty about whether someone had recently received a Td vaccine should not rule out the requirement for receiving the combined vaccine that also protects against pertussis.

In 2005, ACIP recommended an interval of at least 5 years between doses to reduce the risk for local and systemic reactions after Tdap vaccinations. Yesterday's vote supported the removal of the interval language and states that "Tdap can be administered regardless of interval since the last tetanus or diphtheria containing vaccines."

"Reported adverse events from the receipt of Tdap of intervals of less than 2 years is the same for those given at intervals of 2 or more years, and the current language is a perceived barrier," Dr. Liang said.

According to the CDC, Tdap vaccination opportunities might be missed because of the reluctance of healthcare providers to vaccinate patients who received a Td dose within the past 10 years or had unknown vaccination status.

At this time, 2 single-dose booster vaccines are indicated for use in adults in the United States: Boostrix (GlaxoSmithKline Biologicals) and Adacel (Sanofi Pasteur). "There is no preference of a specific Tdap product," Dr. Liang said.

California Pertussis Vaccine Mandate

ACIP also discussed the burgeoning number of pertussis cases in California, which has reached the highest number since 1960. The state has reported 6257 cases to date this year, and 10 infants aged 2 months or younger have died.

"Many of the fatal cases had multiple contacts with healthcare providers before pertussis was diagnosed," said Kathleen Harriman, PhD, from the California Department of Public Health, during her presentation, and "several had family members with cough illness."

Current estimates suggest that about 93% of 2009 California kindergarten entrants had 5 doses of Tdap, with the rates of immunization in Hispanic infants and adolescents being comparable to that in whites.

In September 2010, a Tdap vaccine mandate in California schools grades 7 to 12 was signed into law; it will begin in 2011.

The CDC is not obligated to follow the ACIP's suggestions, but it usually does.

Source: Medscape Today