By Jyoti Madhusoodanan
Amid new teachers and first homework assignments, the start of the school year often brings sniffles, coughs, and other signs of infectious diseases. In some parts of the U.S., going back to school can also mean a greater risk of students coming down with vaccine-preventable illnesses. In California, for example, the parents of approximately 3 percent of children opted out of having their kids vaccinated on the basis of their personal beliefs this year, according to the state’s Department of Public Health. This state-wide opt-out rate has nearly doubled in recent years, KQED’s State of Health blog reported this month (September 11).
The proportion of unvaccinated children in California schools varies by county, with some reporting opt-out rates as high as 7.5 percent. As these numbers increase, herd immunity—a population’s ability to prevent disease transmission because the majority of people are inoculated—begins to collapse, raising the risk of preventable infections such as measles and pertussis, also known as whooping cough.
In its most recent tally of California’s continuing whooping cough epidemic, the US Centers for Disease Control and Prevention (CDC) reported nearly 8,000 cases of pertussis in the state this year; 267 of those cases were severe enough to require hospitalization.
And it’s not just California that’s seen a recent surge in pertussis: several Washington, DC-area schools reported more than a dozen cases just last week. Minnesota has reported 708 cases already this year. Nationwide, there have been more than 17,000 reported cases of whooping cough since the start of 2014, according to the CDC.
While treatable with antibiotics, pertussis can be serious. The protracted fits of deep, violent coughing caused by this pathogenic bacteria leave infected adults breathless for weeks; in infants, the paroxysms can lead to cracked ribs, collapsed lungs, and even death.