The COVID-19 pandemic has forced millions of children around the world to miss important childhood vaccines, increasing the risk of dangerous outbreaks of other infectious diseases, new research suggests.
Amid the spread of the coronavirus, it is estimated that 9 million more children than expected did not receive a first dose of the measles vaccine in 2020, researchers reported on July 14 in a model study in the Lancet. Another 8.5 million children are projected to have lost a third dose of DTP against diphtheria, tetanus and whooping cough, or huge cough.
The World Health Organization and other public health agencies warned last year that the COVID-19 pandemic would disrupt routine childhood vaccines. Those missing vaccines could put vulnerable children at risk during outbreaks of highly contagious diseases, such as the 2014 measles outbreak at Disneyland in California (SN: 13/11/20). The news also comes as Tennessee health officials plan to stop all reach to vaccinate teens to prevent not only COVID-19 but other infectious diseases as well.
“We lost more than 4 million people to COVID,” says Suzette Oyeku, a pediatrician at Montefiore Children’s Hospital and Albert Einstein Medical School, both located in New York City. "How many additional lives do we want to lose by not protecting people from things we know we can protect?"
Sign up to receive the latest from Science News
Headlines and summaries of the latest Science News articles, delivered in your inbox
There is some uncertainty in the new Lancet estimates because vaccine data were not available in all countries, says global health researcher Kate Causey of the Institute for Health Metrics and Assessment at the University of Washington in Seattle. The actual number of some regions may be smaller or larger.
A separate analysis by WHO and UNICEF, described in a July 15 press release, finds a lower number, although millions of children still lack crucial childhood vaccines.
See our full coverage of the coronavirus outbreak
Based on health care data, the WHO reports that by 2020, at least 3.5 million more children will have lost their first dose of DTP than in 2019. Another 3 million more children have lost their first measles vaccine in 2020 than in 2019. Many children in Southeast Asia, for example, missed their shots. India has seen the largest increase in missed vaccines, according to the WHO study. There, more than 3 million children did not receive a first dose of the DTP vaccine in 2020 compared to about 1.4 million in 2019.
In the Lancet study, Causey and colleagues estimated global coverage of the measles and diphtheria, tetanus, and pertussis vaccine coverage by 2020 by analyzing public health data and mobility patterns. If the pandemic had not happened, it is estimated that 83.3 percent of children would be vaccinated against diphtheria, tetanus and pertussis and 85.9 percent against measles by 2020, the researchers ’models suggest. Instead, 76.7 percent of children received the DTP vaccine, the lowest rate since 2008, meaning 30 million children (8.5 million more than expected) missed the shot, the team found. It is estimated that only 78.9 percent have been vaccinated against measles, meaning that 27.2 million children, or 8.9 million more than expected, missed doses. Experts have not seen a level of measles vaccination in children so low since 2006 (SN: 24/04/19).
That decline is worrisome, especially given the ongoing coronavirus pandemic, Oyeku says. “The concern that we are going to start seeing groups of outbreaks of vaccine-preventable diseases,” as well as outbreaks of COVID-19 in children, can cause problems.
As seen in the WHO analysis, regions such as South Asia recorded the largest decline, and doses of DTP administered fell nearly 60 percent below expectations, the Lancet study suggests. Doses of measles decreased by 40 percent in that region. Sub-Saharan Africa recorded the smallest decline: around 4 percent for both shots.
The team found that high-income countries, including the United States, had a 6 percent drop in DTP vaccines and an 8 percent drop in measles. A separate study published in the June 11 U.S.-based weekly morbidity and mortality report showed that vaccination rates for these vaccines fell in 10 states, including Idaho, Iowa and Washington from March to September 2020 compared to the same period. 2018 and 2019.