We were on a telebriefing this morning with Dr. Anne Schuchat, director, National Center for Immunization and Respiratory Diseases (CDC), and Mary Selecky, secretary, Washington State Department of Health.
They reported that Washington state is a reflection of the national picture of this difficult-to-control disease.
Washington is in the midst of an epidemic, with 3,000 cases so far this year and nine infant deaths. Pertussis (whooping cough) is most dangerous for babies, and more than half who become infected are hospitalized.
In the nation, nearly 18,000 cases have been reported to date, with many states seeing higher numbers of infected than normal.
In 2010, there were 27,000 reported cases and 27 deaths, 25 of those who died were infants.
There has been a gradual and sustained increase of reported cases in the US, and the CDC is in the field trying to determine why that is.
Potential causes of increased numbers could be:
- childhood vaccines provide immunity for a number of years, but that immunity wanes over time
- there has been increased reporting of disease
- there has been an increase in diagnosis of pertussis
In this current wave of disease, the highest rates of infection are among babies younger than one. Babies depend on those around to be immunized so that adolescents and adults won’t pass on the infection to the baby, who is too young to be fully protected by immunization.
There are also higher rates of infection in 10-year-olds, because early childhood immunizations have waned. A booster called “Tdap” (tetanus, diphtheria, acellular pertussis) is recommended for children 11 to 12 years old.
One odd thing that’s going on in Washington and elsewhere is that young people ages 13 to 14 years are also experiencing higher rates of infection. A theory as to a possible cause for this is that this group of teenagers is the first to have had acellular pertussis vaccine only as babies and young children, and no whole-cell pertussis vaccine.
In 1997, the switch was made from whole-cell pertussis vaccine to acellular pertussis vaccine in the US.
It’s just a theory. How that might affect immunity, if it does, is being investigated.
Pertussis vaccine is the most effective approach to preventing infection. Unvaccinated kids have an eight times higher risk of infection compared to vaccinated kids.
Vaccinated kids who get pertussis have milder symptoms, shorter illness, and are less infectious.
In 2010, only eight percent of adults in the US had a history of the Tdap booster.
Throughout today’s telebriefing, Dr. Schuchat and Ms. Selecky emphasized the need for pregnant women and all adults and adolescents to be vaccinated to protect not only themselves, but the babies in their lives, as most babies who are infected acquire that infection from adults and teens around them.
This surge in pertussis cases isn’t just in the US. Australia’s rate of pertussis infection right now is even higher than that in the US, and Canada is struggling.
Moms and dads are losing their babies to this disease. Whooping cough is so infectious—you could be infected and pass it on to a co-worker who then takes it home to his newborn daughter.
Because pertussis is underdiagnosed, many people are infected but don’t know it.
Ask your pharmacist, your doctor, or even your employer about getting the pertussis booster shot. Please.
Image courtesy of CDC