Written by By Sophie Dickens, CNN
Influenza, whooping cough and measles have reached historic highs in the US so far this year, and public health officials say we could be in for a long season of cases as vaccination coverage slips.
In a statement posted to Twitter, the US Centers for Disease Control and Prevention said that while vaccination has been “extremely successful,” the number of mumps cases from February to July is on pace to match or exceed the 29,000 cases in 2017, which was the highest seen in the US since 1949.
“Current coverage in the US is estimated to be about 92% for vaccination, well below levels recommended by the CDC for the overall population,” the statement said.
According to Dr. Anne Schuchat, principal deputy director at the CDC, the proportion of adults who are vaccinated has decreased by 8% in the past decade, with just around one-third of adults who could potentially benefit from mumps vaccines currently getting them.
According to the CDC, the main reason for these losses is because patients who are routinely vaccinated are no longer able to be included in an immunization study. This may be because they no longer actively have the disease, or they might have declined immunization because they are employed and have children. But the threat of mumps has been made worse by significant coverage gains in the past decade among unvaccinated or inadequately vaccinated adolescents and young adults, who account for the vast majority of cases.
Infectious disease expert Neil Risch, a professor of medicine at the University of Pennsylvania’s Perelman School of Medicine, says this is a “bad year for everyone,” including those who received their mumps vaccines when they were young.
According to a report in the Journal of the American Medical Association in July, the number of measles cases has exceeded 457, up roughly 31% from the same period in 2017. Data also show a steep jump in whooping cough cases in April and May of this year, from a historically low number of cases.
“We’re seeing a resurgence of almost all of our vaccine-preventable diseases,” Risch said.
This year, according to the CDC, whooping cough is happening more often among children who are too young to have been vaccinated, especially in the so-called high-risk group — babies under 4 months of age, who are too young to have been vaccinated. “It’s a pretty safe zone. But you can get whooping cough at any age,” Risch said.
Other vaccines that have experienced some recent setbacks include polio and whooping cough. According to a report from the US National Institutes of Health in 2016, measles was highly contagious and capable of spreading rapidly throughout a crowded country like the US.
Risch said the causes of this increase remain unclear, but all of the increase cases are happening in children, especially in the high-risk group. “The infections they were spreading were dying out. So, the adults who were getting whooping cough kind of went elsewhere and nobody took care of them,” he said.
Mumps, which is a contagious viral disease with symptoms that include fever, muscle aches, and swollen salivary glands, was declared eliminated from the US in the late 1980s, but it has been making a comeback, with 18,000 cases last year.
In 2015, the CDC reported a 14-year high in the number of measles cases, reaching measles cases of more than 5,000, largely because of a huge increase in unvaccinated travelers from developing countries, where measles is often easily transmitted. In response, vaccination rates surged to around 92%, but has since begun to fall.
This year, 122 students at a private California school, Pacifica School in Millbrae, California, have been confirmed to have measles, according to records obtained from the California Department of Public Health. Earlier this month, reports also emerged that students at another Bay Area private school, Greenacres School in Concord, California, had been sent home with cough drops and liquid eyedrops for a lack of protection against the highly contagious respiratory illness.