Combatting the global increase in measles

For decades, policy makers and public health practitioners have fought the spread of measles through vaccination. Measles is highly contagious—up to 18 times more contagious than seasonal influenza and three to nine times more contagious than COVID-19—making vaccination crucial. However, despite seeing a 96 percent decrease in measles deaths since the 1970s, the disease seems to be making a resurgence. Cases of measles have been increasing since 2017 and the first half of 2019 saw the greatest number of measles cases in more than a decade. These increases have been linked to decreases in vaccination in recent years.

The first step to counteracting decreases in measles vaccination is understanding what factors are driving that decline. In a new paper published in the journal Current Opinion in Virology, Texas A&M School of Public Health doctoral student Tasmiah Nuzhath and professor Brian Colwell, PhD, working with Hagler Fellow Peter Hotez, MD, of the Baylor College of Medicine, explored these factors, which include war and economic collapse, with a focus on parental refusal to vaccinate their children, something known as vaccine hesitancy. Although wars, civil unrest and economic collapse can prevent children from accessing vaccines, the researchers note that vaccine hesitancy is the main cause of measles returning to the United States in recent years, with measles outbreaks occurring in many urban areas with large numbers of unvaccinated children as well as in close-knit religious and ethnic groups.

In their paper, the researchers identified three major parts of the anti-vaccine movement in the United States. The first of these elements is what they refer to as the media empire. This primarily includes online sources such as websites, e-commerce sites and social media platforms. Websites containing misinformation such as false claims that vaccines cause autism and reports of toxic ingredients in vaccines have been amplified on social media platforms such as Facebook, while books containing incorrect health information are frequently sold on e-commerce giant Amazon. This glut of misinformation makes it difficult for parents to find accurate information on vaccine effectiveness and safety.

The second element highlighted in the study is the prevalence of political action committees that lobby state legislatures to provide additional exemptions for vaccinations under the guise of freedom of choice.

The third element the researchers identified is the rise of anti-vaccine groups that specifically target populations that are somewhat insulated from the wider culture such as various religious and immigrant groups. These anti-vaccine groups have promoted fears about harms caused by vaccines, with misinformation efforts being associated with vaccination declines and subsequent measles outbreaks in Somali immigrants in Minnesota in 2017 and Orthodox Jewish populations in New York City in 2019.

The tactics used by anti-vaccine groups have been gaining steam in recent years and are now being used against mandatory vaccines for human papillomavirus. To stop the decline in vaccination, public health experts will need to develop what the researchers refer to as a new vaccine diplomacy.

Research has found that anti-vaccine attitudes can be reversed with the right combinations of information and influence. Physicians taking time to listen to patient concerns about vaccine safety and effectiveness as well as pain and needle sensitivity will play a key role in vaccine diplomacy. Efforts must also be made to debunk misinformation and oppose non-medical vaccine exemption policies. Communications efforts that reinforce vaccine safety and the potential harm from measles and other diseases will also be important. The researchers note that vaccine hesitancy may become more problematic in other parts of the world, especially those facing civil or economic unrest.

The findings of this study point to an urgent need to counter anti-vaccine efforts and more quickly identify areas where vaccinations may be declining. This will require people with expertise in not only vaccines and viruses, but also public health, economics and psychology among other fields. Without a clear plan that addresses all aspects of the anti-vaccine movement as well as factors like conflict, food insecurity and climate change, there will be a growing risk of widespread vaccine-preventable diseases that public health experts have spent decades working to eliminate.