As if budget woes are not enough, last month the State of California officially declared a statewide whooping cough epidemic. With recorded cases 400 percent higher than last year, including almost 1000 cases in 2010 with five infant deaths, state officials now believe that California is headed for the highest incidence of pertussis, commonly known as whooping cough, in over 50 years.
California is not alone. The CDC notes that the number of reported cases in the United States tripled between 2002 and 2004. Although still a far cry from the 175,000 annual cases diagnosed prior to the introduction of the vaccine, the incidence of whooping cough reported annually in the last decade still represents an alarming increase from the less than 3,000 yearly cases in the 1980s.
The dramatic rise in whooping cough is not limited to the United States. The World Health Organization estimates there were over 17.6 million cases of whooping cough and 300,000 deaths last year alone, making this easily preventable disease one of the world’s leading causes of illness and death. The greatest increase has been in wealthier countries with widespread immunization programs. The rarity of the illness, coupled with concerns about side effects of the vaccine and the use of vaccines with poor efficacy (Canada, Sweden), has led to an increase in the number of inadequately immunized, or unimmunized children, in developed countries. In addition, the whooping cough vaccine does not confer lifelong immunity, which means that adults immunized in childhood are susceptible to the illness. Indeed, almost 25% of whooping cough cases in Europe and the United States are now reported in adults.
Whooping cough is seldom more than a mild inconvenience in those over 10, who may experience prolonged upper respiratory symptoms (runny nose, fever, persistent unproductive cough), but rarely have more serious consequences. Nonetheless, the presence of the B. pertussis infection in adolescents and adults who may transmit the bacteria to infants has led healthcare providers to promote booster immunizations after childhood. However, booster shots have been approved for adults in only a handful of countries (Canada, France, Germany and the United States), which means that there remains a tremendous reservoir of unprotected adults around the globe, even in developed countries. To compound matters further, there is newly emerging evidence that some strains of the bacteria that cause whooping cough have developed resistance to the newer (acellular) version of the vaccine
Fortunately, the CDC now recommends that anyone traveling outside of the United States receive the DTaP (which includes pertussis protection) vaccine prior to travel. Some resistance notwithstanding, compliance should minimize the risk of contracting the illness overseas and passing it on to susceptible infants who tend to suffer more devastating clinical consequences.
