Americans Trusted Vaccines More in Recent Years, but Misinformation Could Put That at Risk

The proportion of the U.S. population who strongly believe vaccines are safe, important, and effective has risen in the past half decade, according to a study.

Between 2015 and 2019, the estimated percentage of the U.S. population who strongly agreed vaccines are safe went up from just over half (51.03 percent) to 61.13 percent. The percentage who thought they were important rose from 63.09 to 74.72 percent, while those agreed they were effective climbed from 56.13 to 65.05 percent.

The findings were among those published in the biggest ever global survey on vaccine confidence, featuring 149 countries and published in the journal The Lancet.

Researchers looked at data from 290 surveys done between September 2015 and December 2019, involving 284,381 people aged 18 years or older. They used the information to estimate public perceptions of the safety, importance and effectiveness of vaccines.

The study was published against a backdrop of growing evidence that people are delaying or refusing vaccines because they do not trust that they are important, safe, and / or effective, the authors wrote. This is compounded by problems with accessing them in some places.

These factors are contributing to a rise in vaccine-preventable diseases, such as measles and polio. In 2019, the World Health Organization named vaccine hesitancy as one of the top ten threats to global health.

Positive attitudes towards vaccination were found to fall in Afghanistan, Indonesia, Pakistan, the Philippines, and South Korea, but improve in European Union member states, including Finland, France, Ireland, and Italy.

The research comes amid the COVID-19 pandemic, the biggest health crisis in a century. There is currently no vaccine to protect against the disease, but almost 200 are being developed, with experts hoping one will be shown to be effective in large scale trials by the end of the year or early 2021. On Sunday, a CBS News poll revealed 79 percent of the U.S. public would not get a shot right away.

The study was limited in several ways, the researchers acknowledged, including because not all the surveys had consistent options for participants to select from, so they had to make assumptions about the different options in the extreme categories of strongly agreeing or disagreeing.

vaccine, stock,getty
A stock image shows a healthcare working holding a syringe. Researchers have explored attitudes towards vaccines around the world.

Lead researcher Professor Heidi Larson from the London School of Hygiene and Tropical Medicine, U.K., said in a statement: "It is vital with new and emerging disease threats such as the COVID-19 pandemic, that we regularly monitor public attitudes to quickly identify countries and groups with declining confidence, so we can help guide where we need to build trust to optimise uptake of new life-saving vaccines.

"One of the main threats to the resilience of vaccination programmes globally is the rapid and global spread of misinformation. When there is a large drop in vaccination coverage, it is often because there's an unproven vaccine safety scare seeding doubt and distrust.

"Sometimes there is a genuine small risk that gets rapidly spread and amplified to appear to be a much larger risk. There are also cases where vaccine debates have been purposefully polarised, exploiting the doubting public and system weaknesses for political purposes, while waning vaccine confidence in other places may be influenced by a general distrust in government and scientific elites."

Professor Grant McFadden, director of the Center for Immunotherapy, Vaccines, and Virotherapy at Arizona State University, who did not work on the study, told Newsweek he would have guessed that vaccine hesitancy would be increasing in the U.S., "given the amount of disinformation and outright lies that circulate widely." He called the results "encouraging."

However, McFadden said the study was limited because: "Statistics remain just that: numbers."

He said: "I am skeptical that the figures in this report indicate true increases in trust of health authorities, but it does say they still trust science."

Professor Jennifer Reich from the Sociology Department at the University of Colorado Denver, who also did not work on the paper, told Newsweek: "This study is a nice reminder that trust in vaccine is still the majority position but also remains somewhat fluid. The level of trust people have in their healthcare providers clearly makes a difference in views of vaccines too."

Highlighting a limitation, Reich, the author of Calling the Shots: Why Parents Reject Vaccines, said: "It is always important to remember that expressions of vaccine confidence do not automatically translate into vaccine behaviors. Trust in vaccine is important.

"But how individuals make decisions about using vaccines—and how strategies may vary within a family or even between children in the same family—is also important to understand."