What We Know About the Measles Comeback

Research tells us some of the reasons this disease is on the rise.

Posted Dec 13, 2019

RawPixel/Adobe Stock
Source: RawPixel/Adobe Stock

The measles is back. This viral illness—one of the most contagious known—can cause serious complications and death among young children. Although eradicated in the U.S. in the year 2000, it has been staging a steady comeback.

Across the globe, the World Health Organization reports a 167 percent increase in the number of measles cases in 2018 compared with 2016. And in the first 9 months of this year, the CDC identified more than 1,200 cases of measles in the U.S.—the highest annual number since 1992.

What’s going on here? 

Across the U.S., public health officials had been able eradicate the disease because of high vaccination rates. Vaccination is the best way to prevent measles because the disease is so incredibly contagious. The signs and symptoms of the measles don’t appear for ten to 14 days after exposure to the virus. During this time, it can spread through mucus in the nose or throat. If a person with measles coughs in a room and then leaves, someone else who enters that room hours later will still come into contact with the virus.

But, due in part to misinformation about vaccines, fewer parents have been choosing to vaccinate their children. Eighty-nine percent of measles patients in the U.S. this year had not been vaccinated for measles or had an unknown vaccination status.

Public health scholars name this problem “vaccine hesitancy.” The World Health Organization includes vaccine-hesitancy among its list of ten major threats to global health.

A systematic review published earlier this year in the journal Vaccine identified the top reasons U.S. parents are hesitant to vaccinate their children. The review included 71 studies that asked participants open-ended questions about vaccinations.

The review found the most commonly-described reasons were that vaccines can cause illnesses, can overwhelm a child’s immune system if they get too many vaccinations at once, and that vaccines contain harmful ingredients. Parents also expressed fears that naturally-developed immunity is better than immunity from vaccines, and that vaccines are simply an avenue for profit-making.

But, in reality, the evidence shows that childhood vaccines are extremely safe. A systematic review published in the journal Pediatrics found rare cases of skin rash, an allergic reaction to an ingredient in the vaccine, and fever. It found no evidence that childhood vaccines lead to autism or leukemia.

This is notable because a fraudulent study published in the British journal The Lancet linked the measles, mumps, and rubella vaccine to autism and colon inflammation. In 2010, the journal fully retracted the study after media reports that the author manipulated the evidence. Since then, medical scholars have called the debacle “the most damaging medical hoax of the last 100 years.” To help, public health officials have created interventions that can help pediatricians talk with vaccine-hesitant parents.

The take-home message: The most effective way to avoid contracting the measles and reduce the incidence of the disease across the country is to make sure that everyone is vaccinated.

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