This month, four children were admitted separately to a hospital in the central Indian state of Maharashtra with symptoms of breathlessness and falling blood pressure.
Their mothers had contracted Covid-19 more than a month ago. The children had developed no symptoms of the disease. At the 1,000-bed Kasturba Hospital in Sevagram, the young patients, however, were found to have antibodies to Covid-19, indicating past infection.Now they were battling a rare, inflammatory and potentially life threatening condition called multi-system inflammatory syndrome (MIS-C). This condition usually develops four to six weeks after children and teenagers have recovered from Covid-19.
At the Kasturba Hospital, two of the sick children have recovered, while the other two are being treated in intensive care. "I would worry about this condition. We simply don't know how deep this problem is. It is worrisome we still don't have data on the burden of this disease in India," Dr SP Kalantri, medical superintendent of the hospital, said.
As the deadly second wave of the coronavirus abates, paediatricians across India are reporting more cases of this rare but serious condition. Since doctors are still reporting cases, it is not clear how many children have been affected so far. The US has reported more than 4,000 such cases and 36 deaths from the disease so far.
At Delhi's Gangaram Hospital, Dr Dhiren Gupta, an intensive care paediatric, has seen more than 75 patients, aged between four and 15, since March, when the second wave began. His hospital has opened an 18-bed MIS-C ward. He reckons there have been more than 500 such cases in the capital and its suburbs.
Nearly 1,500km (932 miles) away, in the western city of Pune, Dr Aarti Kinikar, a paediatrician working in a government medical college and hospital, has seen 30 such cases since April. Thirteen of the sick children, aged four to 12 years, are still in hospital. Most of them have suffered from myocarditis, a disease marked by the inflammation of the heart muscle. "The numbers are too many after the second wave," Dr Kinikar said.
In Solapur, a small town in Maharashtra, fellow paediatrician Dr Dayanand Nakate, has dealt with up to 20 patients, mostly between 10 and 15 years old, in the past month. Last fortnight the Maharashtra government made MIS-C a "notifiable disease", required by law to be reported to authorities.Doctors say the condition is the result of an extreme immune response to the virus, which can lead to inflammation of vital organs.
Symptoms can often mimic other diseases at the start: high and persistent fever, rash, red eyes, inflamed lymph nodes, stomach pain, low blood pressure, body ache and lethargy.
Some symptoms are similar to Kawasaki disease, another rare condition that mainly affects children under the age of five. "The syndrome is really a spectrum of conditions from mild Kawasaki-like disease to multi-organ failure," according to Dr Jhuma Sankar, an associate professor of paediatrics at Delhi's All India Institute of Medical Sciences (AIIMS).
The inflammation surge, say physicians, can lead to frightening outcomes: septic shock, respiratory failure and affect multiple organs like the heart, kidney and liver. Children afflicted with this condition also show neurological symptoms, a study in the US found.
Dr Gupta told me that the majority of sick children in his hospital required critical care treatment. A third had to be put on ventilator support for up to a week. Experts say steroids, antibiotics, immunoglobulin or IVIG injections - made from the blood of donors and containing millions of healthy antibodies - and oxygen support may help make children make a recovery.
Worryingly, 90% of the children Dr Gupta's hospital treated for the condition had contracted Covid-19 without showing any symptoms, he said. He said the children became sick with the inflammatory syndrome two to six weeks after recovery.
"My only worry is these children should not crash and land up in extreme emergency. Parents need to watch out and take children who have recovered from Covid and develop symptoms to a paediatrician," Dr Gupta said.
"What also worries me is whether we have enough resources and facilities to treat these young patients if there's a spike in cases."
The inflammatory condition remains rare, and if treated in time, mortality appears to be low: only one of the 23 patients in four Mumbai hospitals who were afflicted with the condition and examined as a part of a study, died. The Royal College of Paediatrics and Child Health in UK - where the condition is called Paediatric Multisystem Inflammatory Syndrome or PIMS - has said mortality numbers are not available yet, but said deaths "would be extremely rare".
In Pune, for example, paediatricians are putting together instruction leaflets for parents and providing online training to health workers and caregivers to treat sick children at home.
What is still not entirely clear is what causes this condition. Is it related to the build-up of antibodies after a Covid infection? Or does this syndrome develop after the infection on its own? Why do a small number of children get affected?
"It's still a bit of a mystery," Dr Banik said.
When to seek help
The US Centers for Disease Control and Prevention recommends parents should seek emergency care right away if their children show any of these warning signs or other concerning signs:
• Trouble breathing
• Pain or pressure in the chest that does not go away
• New confusion
• Inability to wake or stay awake
• Pale, gray, or blue-coloured skin, lips, or nail beds, depending on skin tone
• Severe abdominal pain