This is one in an occasional series about children’s health issues. We know that many of our readers are grandparents keenly interested in the health and well-being of grandchildren. We hope this series will provide readers useful health information you can share with your family.
If you think of whooping cough, you might think of an old-school childhood disease, something that was a big worry in the middle of the last century that holds no great threat now.
You’d be half-right: the peak of the disease was in the 1940s, with about 100,000 U.S. cases and thousands of deaths per year at that time; by 1976, as a result of wide-spread vaccination, there were barely a thousand cases.
However, whooping cough was never eliminated in the U.S. the way polio and measles were, according to Rose Park, Senior Community Health Nursing Director at the Indian River County Health Department, and the disease has rebounded with 28,000 cases in the U.S. last year.
“There’s always a chance for it to get into a community,” Park says. “That’s why vaccination is so important to protect the health of our families.”
Unfortunately the current vaccine seems to be losing effectiveness at the same time as the disease germ gains traction, and recent research suggests a new vaccine may be needed to prevent increased outbreaks.
Whooping cough, also known as pertussis, is a highly-contagious respiratory tract infection; it is characterized by an explosive cough, violent enough to break ribs. It can be very deadly – in 1920, pre-vaccine, there were more than 10,000 whooping cough deaths in the U.S. The first widely-used vaccine was introduced in 1948, and in subsequent years the incidence of the disease plummeted.
That vaccine was known as the whole-cell vaccine; it was created by killing the pertussis bacterium with an antiseptic and injecting it into the body. It was loaded with several thousand proteins, including toxins, to fire up the immune system. It was very effective, but did cause side effects in some children, including pain at the injection site, fever, persistent crying and, in rare cases, seizures.
In 1982, an NBC documentary claimed the whole-cell vaccine could cause permanent brain damage. Paul Offit, director of the Vaccine Education Center and a professor of pediatrics in the division of infectious diseases at the Children’s Hospital of Philadelphia, says, “It cast a negative light on the whooping cough vaccine. Even physicians didn’t understand that it didn’t cause permanent brain damage.”
In 1990, a study published in The Journal of the American Medical Association refuted the brain damage theory; nonetheless, a new vaccine was introduced in 1998. Made from components of the bacterium rather than the whole cell, it causes fewer side effects but appears to be less effective. The Centers for Disease Control and Prevention reports that in 2014 there were more than 28,000 U.S. cases; from 1970 to 2001, there were never more than 8,000 cases in a single year.
According to recent research, the newer vaccine (called acellular), has led to additional transmissions of whooping cough and the rapid increase in cases seen since the early 2000s. Simply put, people can be vaccinated against whooping cough and be asymptomatic (show no symptoms), but still be infected and potentially transmit the disease to others.
The researchers, Benjamin M. Althouse and Samuel V. Scarpino, are postdoctoral fellows at the Santa Fe Institute. They studied the whooping cough bacterium and concluded that the switch from the whole-cell vaccine to the less-effective acellular vaccine is responsible for the recent increase in incidence.
Althouse and Scarpino acknowledge that the bacterium that causes whooping cough has evolved enough to develop some resistance to the acellular vaccine, but this evolution alone does not explain their data; they say asymptomatic transmission must be considered. The danger is that asymptomatic people do not change their behavior, continuing to come in contact with many people – including children.
The researchers believe that a new, more effective vaccine is needed, but at this time the acellular vaccine is the best we have, and unvaccinated children are eight times more likely to get whooping cough than those who have received all recommended doses.
Ms. Park says, “For maximum protection, infants and children should get 5 doses of the vaccine, at age 2 months, 4 months, 6 months, 15 to 18 months, and at age 4 to 6 years.” She also says that preteens should get a “booster” dose at age 11 or12; as should teens and adults who did not receive that dose as a preteen. “Protection levels are highest within the first two years of vaccination,” she says. “And even people who have had the disease are not immune.”
Whooping cough is remarkably tenacious, with a frightening capacity to spread. A single case generates 12 to 17 additional cases; by comparison, each case of Ebola (a rare and deadly viral infection) is estimated to generate 1.5 to 2 more cases. Additionally, there is a major whooping cough outbreak every four years or so, and the number of cases spikes.
Antibiotics are often prescribed for children and adults who are diagnosed with whooping cough; they shorten the period of contagion and help prevent further spread.
The Indian River County Health Department is located at 1900 27th Street in Vero Beach; the phone number is 772 794 7400.
