Child COVID-19 vaccinations may grant protective effect against symptomatic asthma

Key takeaways:

• States with low vaccination rates experienced a lower decrease in asthma symptoms.
• High vaccination rates may have contributed to herd immunity and lowered asthma symptom prevalence further.

COVID-19 vaccination may grant protection against symptomatic asthma in children, according to a study published in JAMA Network Open.

Prophylactic benefits were seen in children receiving COVID-19 vaccinations against SARS-CoV-2 infections. The vaccine may also have protective qualities from other human coronaviruses through cross-reactive antibody responses, Matthew M. Davis, MD, MAPP, executive vice president, enterprise physician-in-chief and chief scientific officer at Nemours Children’s Health, Wilmington, Delaware, and Lakshmi K. Halasyamani, MD, chief clinical officer at Endeavor Health, Evanston, Illinois, wrote.

“Asthma is one of the most common chronic health conditions for children in the United States,” Davis told Healio. “Any opportunity to prevent asthma symptoms and keep children more healthy is appealing. My coauthor and I were aware that asthma symptoms decreased during 2020, and we wondered what factors were associated with persistently lower levels of asthma symptoms in 2021.”

This cross-sectional study used state-level data from the National Survey of Children’s Health from 2018 to 2019 and 2020 to 2021, regarding parent-reported current asthma symptom prevalence in their children.

Data were also taken from the CDC from 2020 to 2021 regarding age-adjusted COVID-19 mortality rates, the proportion of population aged 5 years and older who completed the COVID-19 primary vaccination series and, through August 2021, the face mask requirements in enclosed spaces in 20 different states as well as the District of Columbia.

Davis and Halasyamani analyzed state-level change scores and time trends for the years 2020 to 2021 vs. 2018 to 2019 in parent-reported asthma symptom prevalence.

The mean prevalence of parent-reported childhood asthma symptoms on a state level decreased from 7.77% (95% CI, 7.34%-8.21%) in 2018 to 2019 to 6.93% (95% CI, 6.53%-7.32%) in 2020 to 2021. The absolute mean change was –0.85 (standard deviation [SD], 1.26) percentage points.

In terms of COVID-19 mortality rates, the mean age-adjusted rate in 2020 was 80.3 (SD, 30.2) per 100,000 population, which then increased to 99.3 (SD, 33.9) in 2021. The COVID-19 primary series vaccination rate mean through December 2021 was 72.3% (SD, 10.3%).

COVID-19 vaccination rates were inversely correlated with the COVID-19 mortality rates in 2021 (r = –0.75; P < .001). However, in 2020, that correlation was not observed (r = –0.2), but a positive correlation was seen with face mask mandates (r = 0.49; P < .001).

Parent-reported child asthma symptom prevalence decreased by 0.36 percentage points (P = .04) with each increase of 10 percentage points in COVID-19 vaccination coverage. There was no association between face mask requirements and child asthma symptom prevalence.

The top five states with the highest asthma symptom prevalence decrease between 2018 to 2019 through 2020 to 2021 were the District of Columbia (–3.5), New Jersey (–3.2), Maine (–3.1), Nebraska (–2.9) and Rhode Island (–2.5). The states seeing the highest increase in prevalence were New Mexico (2.7), Utah (1.6), Wisconsin (1.4), Georgia (1.1) and Arkansas, North Dakota, Pennsylvania and Texas all at 0.6.

Davis and Halasyamani emphasized that the states in the highest quarter of COVID-19 vaccination rates showed an almost three times decrease in asthma symptoms compared with states in the lowest quarter of vaccination rates.

Specifically, asthma symptoms decreased by 1.7 percentage points for the highest quarter of states and by 0.6 percentage points for the lowest quarter between 2018 to 2019 and 2020 to 2021.

“Children living in states with higher COVID-19 vaccination rates experienced lower rates of asthma symptoms than children living in states with lower COVID-19 vaccination levels,” Davis said. “In contrast, rates of asthma symptoms did not differ at the state level related to COVID-19 mortality rates or whether states continued to require the use of face masks in public spaces in 2021.”

Davis further noted that the association of asthma symptoms with COVID-19 vaccination rates, but not with COVID-19 mortality rates, suggests that children with asthma may be benefiting from community-level vaccination coverage in two ways.

“First, higher community-level vaccination rates may be connected to a higher likelihood that children with asthma are vaccinated against COVID-19 themselves,” he said. “Second, higher vaccination coverage at the population level may indicate that children with asthma benefited from ‘herd immunity’ even if they weren’t vaccinated themselves — ie, others’ protection against infection helped reduce the transmission of the SARS-CoV-2 virus overall.”

Davis and Halasyamani wrote that these findings suggest potential benefits for children with asthma from efforts to continue vaccinating children and adults against COVID-19.

“It would be helpful during future pandemics of respiratory illnesses to enroll children with a history of asthma in large studies, so that analyses like this one could be conducted much more readily and with understanding at the level of an individual child with a history of asthma,” Davis said.

Reference:

• States with highest COVID-19 vaccination rates showed steepest decline in pediatric asthma prevalence. https://nemours.mediaroom.com/news-releases?item=123124. Published July 3, 2024. Accessed July 15, 2024.