Health officials are concerned about a spike in measles cases imported from abroad among patients who did not get vaccinated.
The Centers for Disease Control and Prevention (CDC) reports that the number of measles cases reported in the United States thus far this year—131 cases over the 7-month period ending July 31—is the highest level since 1996.
Of the cases reported to CDC’s National Center for Immunization and Respiratory Diseases (NCIRD), 112 were among those who were unvaccinated or had unknown vaccination status. Of the 95 patients who were eligible for vaccination, 63 were not vaccinated because of their parents’ philosophical or religious beliefs.
Measles is a highly contagious disease that can result in serious complications and death. It is consistently one of the first diseases to reappear when immunization coverage rates fall, according to the CDC. Currently, Israel and a number of European countries, including Switzerland, Austria, Italy, and the United Kingdom, are reporting sizable measles outbreaks among populations refusing vaccination. Italy, for example, has had >2000 cases in the last 12 months. Seventeen of the recently reported US cases came directly from abroad, and another 99 were associated with these importations.
“At the national level, I am concerned about our situation because this year is so different, and I want to make sure parents are aware of that,” said Anne Schuchat, MD, director of NCIRD. “Every year the United States experiences importations of measles from other countries, from travelers going abroad, and from people from other countries visiting us here. But what’s really different this year is that once the measles virus is imported here, we are seeing it spread to many more people.”
“These cases resulted primarily from failure to vaccinate,” Dr. Schuchat continued. “The vaccine against measles is highly effective in preventing infections, and high immunization levels in the community are effective at preventing or drastically decreasing the size of outbreaks.”
In the decade before the measles vaccination program began, an estimated 3 million to 4 million US residents were infected each year. Of these, 400 to 500 died, 48,000 were hospitalized, and another 1000 developed chronic disability from measles encephalitis.