The TLDR: A surge in a life-threatening condition called Multisystem Inflammatory Syndrome in Children (MIS-C) is raising alarm among doctors and authorities. We look at why it occurs and whether parents should be worried. 

First, a big caveat

MIS-C is indeed a very serious syndrome but it is important not to be alarmist about its prevalence. There have been around 2000 recorded cases according to data released in February. That said, it is important to remember that only 5.8% of Covid patients hospitalised in the second wave were 0-19 years old—and that’s up from 4.2% in the first wave. And to put that number in perspective, that 0-19 age group constitutes nearly 43% of India’s population. So neither severe Covid nor MIS-C is common among children. 

Point to note: We don’t have strong data on the number of cases mainly because it is not mandatory for states to report them—and many doctors don’t even know about MIS-C, which is often misdiagnosed. The government recently asked states to start submitting weekly reports, and experts have called for a central registry to track its prevalence. 

Ok, what is MIS-C?

It is not a disease but a syndrome—as in it is a group of signs and symptoms. A number of organs and tissues—such as the heart, lungs, blood vessels, kidneys, digestive system, brain, skin or eyes—become severely inflamed. The red flag symptoms are as follows: 

“It is important for parents to reach out to the doctor if there is a fever (above 100.4 degrees Fahrenheit or 38 degrees Centigrade) lasting longer than 24 to 72 hours and there is a rash on the body, peeling of skin of the tips of the fingers, neck pain or swelling, fiery red eyes or strawberry-like red tongue, abdominal pain, vomiting, diarrhea, fatigue. It's crucial for parents to take the child for emergency care if the child is drowsy, lethargic, confused, has trouble breathing, complains of pain or pressure in the chest, complains of severe abdominal pain, has seizures, or has pale or gray or blue lips, skin or nail beds.”

What’s really scary: about MIS-C is the following: 

• The condition typically develops two to five weeks after a child is infected—and may even seem to have recovered. That’s when a child’s body has produced its maximum level of antibodies to the virus—and they trigger a hyper inflammatory response.
• In 1000 cases studied in the US, over 75% of the kids were asymptomatic. As one doctor says, “That’s the frightening part. It can develop even when parents don’t know their child has had Covid-19.”
• The condition becomes serious very quickly: “It happens so rapidly, and the kids are so ill, that 70 percent will require admission into an ICU.”
• Also this: “It can lead to heart, respiratory or renal failure. The long-term quality of life in children who recover depends on how badly the organs were affected. It’s crucial to catch it early when it is fairly easy to treat.”
• But the symptoms of MIS-C mimic those of other common diseases, including malaria, viral fever, dengue or typhoid which are common in India during the summer. And many doctors are not aware about MIS-C. So early detection is often rare.

Point to note: The US study found a worrying association between asymptomatic Covid patients and MIS-C:

“Many experienced significant heart issues: over half developed low blood pressure, 37% developed cardiogenic shock and 31% experienced cardiac dysfunction involving their heart’s inability to pump adequately. The study said that a significantly higher percentage of patients who had not had Covid-19 symptoms experienced those heart problems, compared with those who had initial coronavirus symptoms. A greater percentage of initially asymptomatic patients also ended up in intensive care.

 

‘Even the kids with severe MIS-C, who were in the I.C.U. — the vast majority of them did not have a preceding illness that they recognized,’ said [infectious disease expert] Dr. Roberta DeBiasi.”

What causes MIS-C?

Researchers are not exactly sure why a child’s body goes into inflammatory overdrive. The latest research published in May suggests that MIS-C kicks in when viral particles in the gut make their way into the blood:

“They found that weeks after an initial SARS-CoV-2 infection, kids had viral RNA in their stool and antigens in their blood along with markers of a leaky gut, suggesting that the trafficking of antigens—specifically, the SARS-CoV-2 spike protein—from the gut to the bloodstream might be driving MIS-C.”

To put it in plain English: 

• Researchers have found that bits of the virus linger in the gastrointestinal tract long after it has disappeared from other parts of the body. 
• Specifically, these are fragments of the virus’ spike which resembles bacterial toxins known as ‘super antigens.’ 
• These proteins are known to trigger an excessive reaction from T cells—which play a key role in our immune system. 
• When they ‘leak’ from the gut into the bloodstream, it triggers MIS-C.

What’s the treatment for MIS-C?

Since doctors are still learning about the condition, they have not developed a sure-fire cure. The standard treatment includes intravenous immunoglobulin (IVIG)—an anti-inflammatory blood product—as well as steroids and monoclonal (synthetic) antibodies. Small studies indicate that a combination of IVIG and steroids is more effective. The primary effort is to control the symptoms as quickly as possible:

“Treatment will be supportive (IV fluids and medicines to improve the function of the heart and the blood pressure), IV immunoglobulin and steroids (to control inflammation) and medicines like Aspirin and Low Molecular Weight Heparin as per guidelines (to prevent excessive clotting of the blood).”

The good news: Most children recover from MIS-C irrespective of the severity of their condition. And a recent study shows that they rarely suffer from long-term effects—apart from muscle weakness and anxiety—even when they were hospitalised, put on the ventilator etc.

The bottomline: There have been a number of news reports predicting a rise in MIS-C cases, but this is true of any Covid-related condition—which will inevitably increase if there is a spike in overall numbers. What worries pediatricians is the fact that children have no access to a vaccine. Covaxin is still holding trials, while Pfizer has not entered the Indian market as yet. And the government has not approved vaccines for kids under the age of 18. So without a vaccination, vigilance remains the only antidote.

Reading list

This op-ed by Dr. Sivaranjani Santosh on NDTV offers an excellent overview of MIS-C. National Geographic and The Scientist have more on the causes of MIS-C. Scientific American has a deep dive on the search for an effective treatment. New York Times looks at the association with asymptomatic patients and the long-term effects of MIS-C.