On the red eye this week from Seattle to NYC I was reminded of Washington State’s Whooping Cough (pertussis) epidemic. It was a full flight and at least ten people seated near me had deep hacking coughs the entire flight. It’s likely that at least a few of them had untreated pertussis and have now spread it to susceptible people. There were a few small infants on the flight and they are the most vulnerable to getting severe pertussis and dying of it. Adults with pertussis can have a cough that is so forceful it can cause them to vomit. A milder form of the cough can last for months. And pertussis is highly preventable with appropriate vaccination.
In Washington State we are in the midst of a pertussis epidemic. Mary Selecky, the Secretary of Health at the Washington State Department of Health, officially declared an epidemic on April 3, 2012, even though epidemiologic data indicate that pertussis cases exceeded the epidemic or outbreak threshold in late December, 2011. Declaring an epidemic allowed Governor Christine Gregoire to mobilize state emergency funds to provide more pertussis vaccinations to uninsured people in Washington State. It also allowed her to call on assistance from the federal government in the form of CDC investigators to monitor and advise intervention strategies.
According to the Washington State Department of Health website, through the week of May 19th, a total of 1,738 cases of pertussis have been reported in Washington State for 2012, compared to 146 cases for the same time period in 2011. Since January 114 infants less than 12 months have been hospitalized with pertussis; 23 of those were under three months of age and presumably were the sickest and probably required the longest hospitalizations. No deaths have been reported from this year’s pertussis epidemic in the state.
Current US recommendations for vaccination against pertussis include the usual combination childhood vaccination series starting at two months of age, then a booster shot for adolescents ages 11-12 years. A more recent recommendation is for an additional booster shot for adults who are parents or caregivers of infants less than 12 months of age—the idea being that if the adults are vaccinated they are less likely to get pertussis and pass it on to susceptible infants in their care. Health care providers, especially the front-line staff of nurses, are included in this recommendation. This approach of targeting pertussis vaccination to the main caregivers of infants is called cocooning.
I’ve been monitoring the news coverage of Washington State’s pertussis epidemic. The Seattle Times published an article, “Whooping cough epidemic declared in Wash. State” (Donna Gordon Blankenship, 5-10-12). In her article, Ms. Blankenship emphasized the need for adults to get vaccinated as a way to protect infants, and quoted a CDC official calling this a “cocoon of protection.” She also quoted this same CDC official as stating that Washington State’s current pertussis epidemic has nothing to do with the anti-vaccination movement, and instead attributed it to better disease surveillance, the cyclical nature of pertussis infections, and an aging population with waning immunity as the vaccine wears off. That all made sense to me—except for the matter of it not being related to the antivaccination movement. How could it not be at least partially responsible for the current epidemic?
A New York Times article “Cutbacks hurt a state’s response to whooping cough” (Kirk Johnson, 5-12-12) emphasized Washington State’s budget crisis and recent cuts to the public health infrastructure as contributing factors to our states’ current pertussis epidemic. He pointed out that changes in the vaccine to make it have less side effects have also made it less effective over—immunity tends to wane faster. He included quotes from a school nurse (yeah school nurses!) in Skagit County, north of Seattle, which is the hardest hit county so far. He referenced the fact that Washington State has the highest percentage of parents who voluntarily exempted their children from vaccines out of fear of side effects or for philosophical reasons. Studies have shown that vaccine refusers tend to cluster, are often middle-class, college educated white people with antigovernment, anti-establishment views. They like living in the Eco-topia of Puget Sound.
A related topic I find fascinating is the seemingly rising trend of antivaccination sentiments among nurses—and the fact that an astonishingly low percentage of pediatric nurses get the booster vaccine for pertussis, despite CDC recommendations for them being part of the ‘cocooning’. I’ll deal with that issue in a follow-up post next week—unless I come down with pertussis thanks to my airplane seatmates. (I have had the pertussis booster so am counting on it working.)