A three-fold increase in the number of New Mexico children exempt from required vaccinations may be a factor in the growing incidence of whooping cough here in recent years, health officials said Tuesday.
New Mexico law allows parents to exempt their children from required vaccinations by claiming a religious or personal belief that forbids vaccinations.
The number of New Mexico children exempt from required vaccinations has tripled since 1999 to nearly 3,400, a recent New Mexico Department of Health report shows.
The rate of New Mexico children exempt from vaccinations was 5.8 per 1,000 children in 2011, up from 2 per 1,000 in 1999.
New Mexico also has experienced a spike in pertussis, or whooping cough, from 85 cases in 2009 to 274 cases in 2011, according to state Department of Health data.
About 112 pertussis cases were reported this year through May 5. Pertussis is a highly contagious bacterial illness that attacks the respiratory system.
Health officials remain uncertain what role vaccine exemptions play in outbreak of preventable diseases such as pertussis, said David Selvage, a state Department of Health epidemiologist.
“When you look at cases of pertussis, if you are in an area where there are an increased numbers of vaccine exemptions, there’s an increased chance that you’re going to be in a pertussis cluster,” Selvage said.
Complicating the problem is the pertussis vaccine itself, which may not offer full protection.
The vaccine “is the best protection we have against pertussis, but it’s probably somewhere in the neighborhood of 80-to-85 percent effective,” he said.
The protection offered by the vaccine also wanes after several years, requiring adults to get a periodic Tdap booster.
The death this month of a 2-month-old San Miguel County infant was the first pertussis-related death of a New Mexico infant since 2005.
Health officials remained uncertain how the infant was exposed to pertussis. The infant had received the first in a four-dose series of childhood pertussis vaccinations, called DTaP, the agency said. Infants 6 months and younger are most vulnerable to whooping cough because they have not received multiple doses of pertussis vaccine, said Dr. Joan Baumbach, the state’s medical epidemiologist.
Pregnant women and anyone else who expects to be in contact with an infant should get a Tdap booster shot, she said.
- Children should receive the four-dose DTaP pertussis vaccine series between ages 2-18 months and DTaP boosters before elementary and middle school.
- Pregnant women should receive a Tdap booster after the 20th week of pregnancy.
- Anyone who expects to have contact with an infant should receive a Tdap booster.
- Source: New Mexico Department of Health
— This article appeared on page C01 of the Albuquerque Journal