Peter J. Hotez
Paul A. Offit
A state of emergency has been declared in Clark County, Washington, after 34 people were infected with measles during a statewide outbreak. The proclamation frees up resources from state agencies and departments to assist affected areas.
According to Clark County public health officials, 30 cases occurred in unvaccinated individuals. Vaccination records could not be verified for four cases.
“We identified Clark and Multnomah Counties as anti-vaccine hotspots, or areas where there are large numbers of kids who are unvaccinated because of the very aggressive anti-vaccine lobby in the Pacific Northwest, combined with the fact that they were enabled by state legislators in Washington and Oregon who have allowed nonmedical vaccine exemptions for reasons of personal belief,” Peter J. Hotez, MD, PhD, professor of pediatrics and dean at Baylor College of Medicine’s National School of Tropical Medicine and co-director of the Texas Children’s Hospital Center for Vaccine Development, told Infectious Diseases in Children.
Multnomah County health officials have confirmed one measles case related to the Clark County outbreak. They added that people in Oregon may be at increased risk of exposure.
Children aged between 1 and 10 years have been most affected by the outbreak, with 24 cases reported in this age group. Nine cases were identified in adolescents aged between 11 and 18 years, and one case was observed among adults aged 19 to 24 years. One patient has been hospitalized, according to health officials.
Hotez said he is most concerned about children aged younger than 12 months who are not yet eligible for immunization with measles-mumps-rubella (MMR) vaccine. He said these children are more likely to have permanent damage from complications of infection, including measles pneumonia or encephalitis.
Paul A. Offit, MD, director of the Vaccine Education Center and attending physician in the division of infectious diseases at Children’s Hospital of Philadelphia, told Infectious Diseases in Children that an increase of measles cases is “the canary in the coal mine,” and said it is one of the first vaccine-preventable diseases to return when there is an erosion of herd immunity.
Offit, who is an Infectious Diseases in Children Editorial Board member, added that vaccines are “a victim of their own success,” and because the MMR vaccine has been effective at reducing the annual number of measles cases, people are no longer afraid of the disease.
“I think children are going to have to die in order for people to take this more seriously,” he said. “I don’t think people are scared of these diseases. People see measles as some sort of harmless rite of childhood passage, but it’s not that at all.”
Currently, three states do not allow nonmedical vaccine exemptions — West Virginia, Mississippi and California. Eighteen of the 47 remaining states allow vaccine exemptions for philosophical or personal beliefs.
Offit expressed additional concern about the re-emergence of other vaccine-preventable diseases, including mumps.
“We eliminated measles from the U.S. in 2000,” he said. “Measles has come back because enough parents have chosen not to vaccinate their children. We have never eliminated mumps. You would typically see a couple hundred cases every year. But last year, we had 6,000 cases. We can argue that at some level, the choice to not vaccinate with MMR has also affected the rate of infection with mumps.”
Hotez suggested that a catch-up vaccination campaign is needed for children in affected counties to reduce the likelihood of measles transmission. However, the outbreak could continue for a considerable amount of time.
“Now that the infection is out there, it is going to continue for a while because measles is one of the most contagious and serious of all infectious diseases,” he said. “Right now, if you’re a parent living [in this area], you have to be terrified of bringing your child out in public all because of the self-inflicted wound caused by the anti-vaccine lobby.” – by Katherine Bortz
Olive JK, et al. PLoS Med. 2018;doi:10.1371/journal.pmed.1002578.
Disclosures: Hotez and Offit report no relevant financial disclosures.