New study examining effects of lockdown on allergy development

Professor Hourihan: We want to see children playing on the floor, getting dirty, and being exposed to lots of people in lots of environments. File picture: iStock/PA. 

A new study is to examine if babies born in Ireland during lockdown are more likely to develop allergies.

It will be led by clinician-scientists from the Royal College of Surgeons in Ireland and Temple Street Children's University Hospital.

They will examine whether lower rates of viral infections and improved air quality resulting from the lockdown caused allergic conditions to be more or less common in infants born since March.

Study leader, professor of paediatrics at RCSI University of Medicine and Health Sciences, Jonathan Hourihan said: “The lockdown presents a unique scientific opportunity to examine the early origins of often lifelong diseases, issues that constitute a major health and social burden in Ireland and other developed countries.” 

Professor Hourihan said Ireland’s Covid-19 lockdown appeared to have reduced the amount of other viral infections, that typically circulate in the community.

He said: “We have seen less than half the usual number of attendances at paediatric emergency departments and rates of seasonal influenza and other late spring upper respiratory viruses seemed much lower than usual during this time.” 

Allergic diseases like eczema, asthma, hay fever, and food allergy have become more common over the last 30 years.

The increase in allergies over the years is thought to result from decreased exposure to infections, due to smaller family sizes, the introduction of effective immunisations against the most serious infections, and community focus on hygiene.

Also, air quality, which has also worsened in Ireland and other industrialised nations over the last 30 years, affects allergic conditions.

Professor Hourihane said: “We want to see children playing on the floor, getting dirty, and being exposed to lots of people in lots of environments. 

"The outcome of this is usually a stronger immune system, linked to a healthy population of gut bacteria, called the microbiome.” 

The study will involve 1,000 infants born in Ireland between March and May 2020.

Allergy tests will be performed at one year and two years old to detect if they have developed markers of allergic conditions. 

If allergies are detected, the children involved in the study will get allergy care faster than they would otherwise.