Beijing, May 12 (IANS): Gastrointestinal symptoms such as diarrhoea, coupled with a fever or history of exposure to COVID-19, could indicate coronavirus infection in children, according to a new study.

Published in the journal Frontiers in Pediatrics, the research also suggests that the gastrointestinal symptoms first suffered by some children hint at potential infection through the digestive tract, as the type of receptors in cells in the lungs targeted by the virus can also be found in the intestines.

"Most children are only mildly affected by COVID-19 and the few severe cases often have underlying health issues. It is easy to miss its diagnosis in the early stage when a child has non-respiratory symptoms or suffers from another illness," said study author Dr Wenbin Li from Tongji Hospital in Wuhan, China.

"Based on our experience of dealing with COVID-19, in regions where this virus is epidemic, children suffering from digestive tract symptoms, especially with fever and/or a history of exposure to this disease, should be suspected of being infected with this virus," he continued.

In this study, the research team detail the clinical features of children admitted to hospital with non-respiratory symptoms, which were subsequently diagnosed with pneumonia and COVID-19.

"These children were seeking medical advice in the emergency department for unrelated problems, for example, one had a kidney stone, another a head trauma," said researchers.

All had pneumonia confirmed by chest CT scan before or soon after admission and then confirmed to have COVID-19. While their initial symptoms may have been unrelated, or their COVID-19 symptoms were initially mild or relatively hidden before their admission to hospital, importantly, four of the five cases had digestive tract symptoms as the first manifestation of this disease.

The researchers also link the children's gastrointestinal symptoms, which have been recorded in adult patients, to an additional potential route of infection.

"The gastrointestinal symptoms experienced by these children may be related to the distribution of receptors and the transmission pathway associated with COVID-19 infection in humans. The virus infects people via the ACE2 receptor, which can be found in certain cells in the lungs as well as the intestines," Li said.

This suggests that COVID-19 might infect patients not only through the respiratory tract in the form of air droplets but also through the digestive tract by contact or faecal-oral transmission.

"We report five cases of COVID-19 in children showing non-respiratory symptoms as the first manifestation after admission to hospital. The incidence and clinical features of similar cases need further study in more patients," the researchers noted.

By highlighting these cases, the researchers hope that doctors will use this information to quickly diagnose and isolate patients with similar symptoms, which will aid early treatment and reduce transmission.

In March, another study from China, published in The American Journal of Gastroenterology, found that diarrhoea was a prominent symptom among up to half of the patients with COVID-19 in Wuhan.