A new study showed that despite social isolation caused by the COVID-19 pandemic, the introduction of allergenic foods was largely completed after 12 months by families with children born under lockdown.
The study was presented on American Academy of Allergy, Asthma & Immunology Annual Meeting (AAAAI) 2022.
In addition, atopic dermatitis and sensitization to eggs were more common in the study cohort during what they called the “COVID-19 era.”
The CORAL study was a longitudinal study examining the impact of the pandemic on allergic and autoimmune dysregulation of 365 infants born in Ireland during the first closure in March-May 2020.
Investigators led by Marguerite Lawler, PhD, Royal College of Surgeons, Dublin, suggested that social and physical changes resulting from the shutdown could have implications for microbiome diversity and allergic sensitization.
Lawlaer and colleagues send out questionnaires to families willing to participate in the survey, which was completed after 6 and 12 months.
At the 12-month review, skin prick tests, COVID-19 antibody tests, and SCORAD assessment of atopic dermatitis were performed. In addition, rates of allergen sensitization were compared with national data from a previous study, BASELINE, from 2008-2011.
Between 6 and 12 months, researchers observed that the introduction of allergenic foods increased from 46% to 99% for cow’s milk, 25.7% to 98.5% for eggs, and 12.4% to 78.2% for peanuts.
In addition, 5.8% (20/344) of CORAL infants were sensitized to eggs compared to 3.18% (45/1540) in BASELINE (p. 50.007), although the frequency of milk and peanut sensitization and medically diagnosed food allergy were similar between cohorts.
However, after 12 months in the CORAL group, the cumulative incidence of atopic dermatitis increased to 87/344 (25.3%) compared with 232/1494 (15.5%) in BASELINE (p <0.0001).
“Atopic dermatitis and egg sensitization appear to be more common in this 12-month-old COVID-19-era cohort,” the team wrote. “Whether this represents a long-term trend over 10 years or short-term changes due to COVID-19 imposed social isolation remains to be determined.”