Pertussis Losses and Immunization Challenges
This week I read another story of an infant who lost her life to pertussis.
It begins with a young wife – a first time mom – responsible for two stepchildren and her newborn daughter while her husband serves his country in Iraq.
Sadly, it progresses like many other pertussis stories.
Sebanna had a persistent cough and some wheezing. Over the course of the next few days, it took several visits to the doctor and the ER before she was admitted into the hospital, and far too long before she was finally diagnosed with pertussis.
Then comes the part that you really don’t want to hear.
Sebanna’s uncontrollable coughing fits got worse. She suffered from blue spells, lack of oxygen, dehydration, and seizures. She was transferred from one hospital to another for specialized pediatric care and hospital staff worked diligently to try to save her. Sadly, Sebanna’s mother Lucy could only watch and pray while they performed an emergency incision to drain Sebenna’s lung.
In the end, Lucy was told that they could do no more. She was left crying and rocking her lifeless daughter, numb with pain and disbelief.
While this is just one pertussis story, Sebanna’s story has been repeated by so many others over the years. Different families with slightly different circumstances, and too many of which have also ended in death.
In 2012, 17 infants lost their lives to pertussis and thousands more were hospitalized. In all, there were 41,880 reported cases in the U.S. last year.
“Whooping Cough doesn’t care how much you love your child, or how good of a parent you are. It simply ravages through and destroys, leaving lifelong scars behind.”
So, how can we prevent these tragedies from being repeated?
While we continue to hear stories like Sebanna’s, public health professionals have been analyzing the data, pouring over the research and working to identify the specific challenges we face in the fight against pertussis.
This week, representatives from Every Child By Two attended a meeting of the CDC’s Advisory Committee on Immunization Practices (ACIP) in Atlanta where they were briefed on the current pertussis data. Thomas Clark, MD, medical epidemiologist for the CDC, gave a detailed presentation which evaluated the current Tdap vaccination recommendations and outlined the possible reasons for the ongoing outbreaks of disease.
Infectious Disease News presented some of Clark’s finding as follows:
- There has been a tremendous reduction in pertussis in the U.S. since the vaccine’s inception, but we’ve seen more recent increases with notable outbreaks in various states.
- In 2000, an emergence of pertussis among fully-vaccinated children aged 7-10 years was likely due to waning of protection from the acellular vaccine.
- In 2012, there was another high period of adolescent disease despite high coverage with Tdap, suggesting that the Tdap booster may wane more quickly than anticipated.
- Despite high vaccination coverage among children, with 96% of children aged 19 months to 35 months having had three or more doses of the vaccine, the national overall pertussis incidence in 2012 was 13.4 cases per 100,000, with the rate reaching as high as 100 cases per 100,000 in some states.
- Infants continue to have the highest risk for pertussis and are most likely to be hospitalized with the disease.
It’s important that this data is considered in connection with the current recommendation that newborns receive DTaP vaccination at 2, 4, 6 months, 15-18 months and again at 4-6 years. After that time, a single dose Tdap booster is recommended for children 11 -18 years of age. The CDC prefers this adolescent booster occur at the younger ages of 11-12 because, as Dr. Clark’s data revealed, antibodies from the pertussis portion of the DTaP vaccine wane over time. Although the vaccine may be 98% effective at warding off disease among fully vaccinated infants, Dr. Clark explained that it may be as low as 71% effective after just five years.
Additionally, adults over the age of 19 should receive a Tdap booster in place of one of their 10-year Td booster (which only offers protection from tetanus and diphtheria). However, in response to the recent pertussis outbreaks – especially among infants who have not yet completed their pertussis vaccination series – the CDC has been encouraging all adults, but in particular, expectant parents and caregivers who are in close contact with infants, to get their booster immediately.
In a further attempt to reduce the risk of pertussis among infants, the CDC recently added a recommendation in January that pregnant women get aTdap booster during each pregnancy, preferably at 27 through 36 weeks gestation.
“By getting Tdap during pregnancy, maternal pertussis antibodies transfer to the newborn, likely providing protection against pertussis in early life, before the baby starts getting DTaP vaccines. Tdap will also protect the mother at time of delivery, making her less likely to transmit pertussis to her infant. DTaP or Tdap (depending on age) is recommended for all family members and caregivers of the infant – at least two weeks before coming into close contact with the infant.”
At the direction of the ACIP, a working group has now been formed to determine the safety and cost-effectiveness of shortening the intervals between revaccination with the Tdap vaccine to combat waning immunity to pertussis. As they work through these challenges and consider new recommendations, there will likely be ongoing conversations about the need for a more effective vaccine. While it is reassuring to know that these issues are being considered, the reality is that these bigger developments will take time.
Until we have something better, we must make the most of what we do have. For instance, data reveals that families are the main source of pertussis infection among infants with mothers responsible for 30-40% of infant infections and all household members responsible for about 80% of infections. However, statistics show that only 13% of adults ages 19-64 were vaccinated with Tdap as of 2011. Perhaps if we can increase the adult Tdap booster rates especially among pregnant women, while we continue to encourage parents to immunize their children according to the recommended schedule, we may still be able to save others from suffering like Sebanna.