A vial containing the acellular pertussis vaccine. (Robyn Beck/AFP/Getty Images)
A new rise in whooping cough cases in California is raising questions among doctors about whether there are problems with the current vaccine. California public health data show a spike in whooping cough cases in 2013 compared to the year before, and last week officials confirmed the first death from the disease since the major outbreak of 2010: an infant in Riverside.
“The attempt at making vaccines safer has created a potential lapse in protection.”
Whooping cough, or pertussis as it is referred to in medical circles, is cyclical in nature and tends to peak every three to five years. But doctors are now finding evidence that the new vaccine may start to wear off on a similar timeline, despite medical recommendations that allow for a span of eight years between booster shots.
“The efficacy of the new vaccine is really good, it works. It’s just that it wanes, and it wanes more quickly,” said Dr. Michael Witte, a pediatrician in Pt. Reyes, north of San Francisco.
The new acellular whooping cough vaccine was introduced in the 1990s. It has fewer side effects than the earlier whole-cell vaccine that had been in use since the 1940s. By 2001, the old vaccine was completely phased out. So while many adolescent kids have received boosters of the new vaccine, they would have gotten shots when they were babies that included the old vaccine. Continue reading
Each green circle depicts a whooping cough outbreak this year. (Map: Council on Foreign Relations)
As the map illustrates, many areas in the country are in the grip of whooping cough outbreaks, everywhere but California. More on California in a minute. Let’s first take a look at a new(ish) vaccine and see how its limitations might be contributing to the outbreaks.
In the 1990s, the U.S. and other developed countries switched from one kind of vaccine against whooping cough (also called pertussis) to another. The older vaccine was very effective but there were concerns about a rare side effect, a neurological disorder, which may (or may not) have been connected to the vaccine. More commonly, the vaccine caused the same minor side effects that we traditionally associate with shots: redness, soreness at the injection site, etc. Except that with the old pertussis vaccine, the side effects occurred more frequently.
In her wired.com blog noted science reporter Maryn McKenna recaps the research and wonders if there could have been an unexpected trade-off with this new vaccine — that it is less effective and therefore contributing to the outbreaks we’re seeing now. From McKenna’s blog Superbug: Continue reading
Pharmacist administers whooping cough vaccine. (Robyn Beck/AFP/Getty Images)
You know public health is working when nothing bad happens. Last year, for the first time in 20 years, California had no deaths from whooping cough, a highly contagious illness also called pertussis.
The California Department of Public Health credits a statewide vaccination effort which followed a 2010 outbreak when 9,000 Californians were diagnosed and nine infants died. In 2011, in addition to no deaths, the number of cases of the illness dropped to 3,000.
As the Los Angeles Times reports: Continue reading