A child getting the measles vaccine in the Philippines.

The threat of measles—a disease thought to be localized to the twentieth century—has risen again in 2021 due to lackluster vaccination rates witnessed during the COVID-19 pandemic. The Centers for Disease Control and Prevention (CDC) is calling the lack of vaccinations unparalleled, saying that “over 22 million infants missed their first dose of measles vaccine—3 million more than in 2019 and the largest annual increase in over 20 years.”

In total, only 84 percent of children received a measles vaccine in 2021 compared to 86 percent in 2019, a considerable gap that allowed the disease to spread undetected in communities for the past several years. Although the CDC recommends that each child be treated with at least 2 doses of a measles-containing vaccine, many children have received none.

The highly contagious virus has waned in severity in recent years, killing nearly 60,000 people a year compared to a million people per year during the 1990s. The large decrease in deaths is largely attributable to targeted vaccination campaigns that sought to rid urban areas from the deadly pestilence.

Worldwide rates of measles vaccinations.

The vaccination rate for measles was the lowest in Africa—a continent where vaccinations for COVID-19 are already predicted to decline in the following months.

Although only 13 U.S. citizens were infected with measles in 2020, the CDC believes that this number is severely underreported, as much of the public health attention and resources have been focused on fighting COVID-19.

With nearly 31 million deaths prevented each year, the measles vaccination program is routinely touted as a leading example of successful vaccination efforts. However, the lack of vaccinations represents a disconcerting theme as the vaccination rates for polio and diphtheria also fell.

In the future, public health officials will not only have to battle anti-vaxxers, but they will also have to counteract a looming shortage of syringes, which has the potential to uproot much of the progress that has already been made.

However, more positively, Australia has not had a single case of measles in 2021, particularly due to the stringent border control measures enacted by the government. The Pacific country, as well as some other developed countries—has seen vaccination rates remain steady for the past several years. Regardless, the World Health Organization believes that more must be done to hamper the spread of measles.

Kevin Cain, the CDC’s Global Immunization Director, says that “we must act now to strengthen disease surveillance systems and close immunity gaps, before travel and trade return to pre-pandemic levels, to prevent deadly measles outbreaks and mitigate the risk of other vaccine-preventable diseases.”