In March 2020, when most of the population, in disbelief and fear, were watching the announcements about a lockdown due to the threat of Covid-19, paediatric consultant Prof Jonathan Hourihane saw a research opportunity. He credits his wife with sparking the idea, as they viewed a TV news report on schools shutting down. She wondered out loud what impact isolation might have on children’s gut biome – a world of micro-organisms that are hugely influential in many aspects of health.
Hourihane, who heads the paediatrics department at the Royal College of Surgeons in Ireland (RCSI) and Temple Street children’s hospital, was quickly on the phone to Prof Liam O’Mahony at APC Microbiome Ireland, a research centre in University College Cork, to propose a study on babies entering a radically different world from the norm. A small grant was secured and off they went, recruiting 360 babies born in the Rotunda and Coombe maternity hospitals in Dublin between March and May that year.
“We’re not aware of a comparable study anywhere in the world,” says Prof Hourihane of the study named Coral (acronym from the wordy title Impact of Coronavirus Pandemic on Allergic and Autoimmune Dysregulation in Infants Born During Lockdown). These “pandemic babies” were being raised in “extraordinary isolation,” under very different environmental and social conditions. Developmental and physiological information was gathered at several stages.
“Some of these babies were only kissed by three people before they were six months. My kids would have all been kissed by about 100 people,” he remarks. “Some of these babies didn’t see any other children till they were a year old.”
Five years later the RCSI research is embarking on a new phase with the Floral (Follow on to Coral) study. This is believed to be the only one of its kind to investigate differences in health outcomes among children born during, and five years after, the pandemic.
The research team, awarded €1.29 million funding from Taighde Éireann – Research Ireland, will reassess the lockdown babies as well as aiming to recruit 1,000 newborns from the same two maternity hospitals, along with the National Maternity Hospital this time, to make a comparison. Parents of new arrivals at those three hospitals in March 3rd-May 30th this year will be invited to participate.
Monica Furlong, whose third child, Eleanor Ahern, was born in the Rotunda in May 2020, had no hesitation in signing up for the first study. She thinks that the “scary” Covid-19 pandemic was a big factor. “We wanted to be part of something that would be of some benefit.”
After an initial questionnaire, she completed another one remotely at six months and was also asked to send a stool sample from Eleanor. Further stool and blood samples were taken at a face-to-face appointment when she was 12 months; allergy testing was also done then. This was all repeated at two years.
The Coral study findings highlighted some unexpected benefits for the pandemic babies, including improved gut microbes due to extended breastfeeding and lower rates of infection and less antibiotic use, as well as lower-than-expected rates of allergic conditions such as food allergies. However, communication and language skills in the group as a whole were slightly lower when compared to a baseline study of pre-pandemic babies, presumably due to lack of socialisation.
[ Small number of lockdown babies have gaps in communication skills, study showsOpens in new window ]
“They didn’t know how to wave or say ‘bye-bye’ because they had no need to wave bye-bye to anybody,” says Prof Hourihane.
Researchers were looking to see if results would support the so-called “hygiene hypothesis”, which originally proposed that first-born children had higher rates of allergic diseases because they didn’t have any exposure to viral illnesses coming through from older siblings. “We thought because [the pandemic babies] weren’t out and about and meeting viruses and illnesses in the normal way, that their allergy rates might go up. But in fact, they didn’t go up.”
This was linked to generally being breastfed longer, possibly because their mothers did not have the pressure of out-of-home activities to attend. However, with Ireland being “infamous” for low rates of breastfeeding, he notes the women who signed up for this study were “nearly all third-level-educated, motivated and interested”.
Another marked difference from the baseline was that the pandemic babies had been given far fewer antibiotics, which can disrupt gut health at a time when microbiome is being established.
Infants share a very similar microbiome with their mothers over the first few months, especially if they’re breastfed, says Prof Hourihane. In the second six months the impact of siblings and other adults becomes more obvious – not by bringing home bad viruses, but by having healthy, diverse microbiome. “Diversity of your microbiome is good for your gut health, and it’s good for your allergy health, your respiratory health, your mental health,” he says. “It decreases the rates of diabetes and other autoimmune diseases later on in life.”
The babies who had siblings had better microbiomes, “better” being more diverse. Variety of diet at the time of weaning to solids also had a positive impact.
Lots of the mums said it was a special time with their child because they didn’t have the other distractions and pulls on their time
The Floral study will look at whether babies’ microbiome and allergy rates are going to revert towards pre-pandemic levels, “or if maybe everybody’s microbiome has changed slightly from being in the pandemic. That’s probably unlikely but we’re going to be able to compare the two groups’ microbiomes directly.” They will also check if the pandemic babies are back on course with developmental milestones.
The new, much larger group of babies will be tracked in the same way as the previous study until the age of two. “It’s a direct head-to-head comparison between two consecutive birth cohorts.”
Prof Hourihan thinks it is also important to remind people how effective the lockdown was in protecting babies from Covid-19 infection. “Babies, who had no possibility of becoming immune to it because their parents had no immunity, were protected by the social isolation that was imposed.”
Eleanor returned from the maternity hospital to a home where there were two stepsiblings, Shona and Thomas, then aged 20 and 18 respectively, as well as her mother, and her father, Eoin. Those early months were very different, says Monica, from what she had experienced after the births of her older children.
She did not manage to breastfeed Eleanor as long as she had hoped and stopped at eight weeks. “It just didn’t work out for me.” Whereas she continued up to nine months with her eldest.
There was no chance to attend mother-and-baby activities in 2020. They tried to do some socialising, from a distance, at a local playground. One of the benefits of the Coral study, says Monica, was the opportunity to meet other parents and babies in a similar situation when they were called to the in-person appointment one year later.
Contrasting maternal experiences were reported in the questionnaires. “Lots of the mums said it was a special time with their child because they didn’t have the other distractions and pulls on their time,” says Prof Hourihane. “Other mothers were devastated and lonely. Postnatal depression was worse because they couldn’t even have their mam in to see them.”
There are learnings from the Coral study, he suggests, for our culture of low breastfeeding rates and overuse of antibiotics, as well as the need for varied weaning foods.
“The babies who had a more diverse diet as they started to wean had a more favourable microbiome too. They had beans and pulses and nuts in their diet at six months instead of just sweet potato and avocado, which is the sort of slow start that people take. We want as wide a range of food introduced as early as possible.” There is a case for educational campaigns, he suggests.
“At a public-health level, it looks like the diversity of your diet when you’re switching to weaning and the impact of your siblings’ and your mother’s microbiomes are things that would cost nobody anything to fix.”
No one should underestimate the significance of gut microbiome. “You have more bacteria in your gut that aren’t human than you have human cells in your body – that’s how important it is,” says Prof Hourihane. “They’re not there by accident. It’s not like we’re dirty; they’re meant to be there and we’re thriving on all the products that they produce that are pro-tolerance and anti-infection, anti-inflammatory.”
Monica encourages qualifying new parents to register for the Floral study. She and Eoin did consider if they should be putting Eleanor through the possible discomfort of allergy and blood tests. But, as it turned out, it was all done in such a fun way, their daughter did not even notice and such a positive first experience of hospital can only be a good thing.
Another benefit, she adds, was having her checked for allergies so early.
