As more students return to school for face-to-face learning over the coming weeks, you’ve been asking us plenty of questions about how this coronavirus impacts kids.
There’s still a lot scientists want to better understand about how the virus SARS-CoV-2 and the disease COVID-19 affect the younger people in our lives.
And by “kids”, we’re generally referring to people under the age of 18, although some studies have a tighter definition, like under the age of 15.
We put some of your most common questions to the experts. Here’s what they said.
1. How does coronavirus affect kids differently to adults?
Children are making up a small proportion of diagnosed cases of COVID-19 both here and overseas, which suggests they’re getting infected with the virus much less frequently than adults.
And generally when they get the disease, young children appear to have mild or no symptoms, said consultant paediatrician Kirsten Perrett of the Murdoch Children’s Research Institute (MCRI).
“Obviously severe COVID-19 in children does happen, but it is extremely rare.”
SARS-CoV-2 really hasn’t followed the textbook on how respiratory viruses should behave, Dr Perrett said.
“Most of the time [with] respiratory viruses such as influenza, children are actually more susceptible to infection and severe disease. But this is not the case that we’re seeing with COVID-19.”
2. Does that mean kids are less infectious than adults?
Not necessarily. A study led by German virologist Christian Drosten, which hasn’t yet been peer-reviewed, found that viral load, or how much of the virus infected people have, didn’t vary that much between different age groups.
“If a kid gets infected, there’s a chance they could infect another individual,” said virologist Kirsty Short of the University of Queensland.
But the point is, Dr Short said, fewer kids are getting infected, so the risk of them as a group being responsible for a lot of transmission is much lower.
3. What role are kids playing in the spread of coronavirus?
Kids appear to be playing a very small role in the spread of this virus.
Dr Short and her colleagues reviewed the global literature to see how often it was kids who were bringing the virus home, and initiating clusters of cases in households. Their paper is available as a preprint, meaning it has not yet been peer-reviewed.
“So in less than 10 per cent of cases was it actually the child bringing the infection into the house,” she said.
This is in comparison to avian flu, another emerging viral infection, where using the same approach they were able to show kids drove about 50 per cent of the transmission clusters.
That kids are not walking and talking coronavirus spreaders may be counterintuitive to a lot of people.
“One hundred per cent honesty, when we started this study that was my hypothesis, so I’ve come full circle,” Dr Short said.
And that’s good news for schools, said infectious disease physician and microbiologist Peter Collignon of Canberra Hospital and the Australian National University.
“If this was influenza, we would keep schools closed until this was over,” Professor Collignon said.
4. Do we know why kids don’t get COVID-19 as much as adults?
No, but it’s something we’re investigating, Dr Short said, as understanding that could also be of therapeutic benefit for adults who get severe forms of the disease.
One possibility is it could have something to do with how kids’ immune systems are different to adults’.
There are two types of immunity that we generally talk about, Dr Perrett said.
There’s the innate immune system, which is the first but non-specific response.
Then five to 10 days after the start of the infection, your adaptive immune system kicks in, which is a more specific or tailored response to the particular pathogen.
Kids’ immune systems are more immature than adults’, Dr Short said, because our immune systems develop as we get older and we come into contact with different pathogens.
But kids’ immune systems are better at dealing with infections that they’ve never seen before, and their non-specific immune response is more active.
“The fact that they have a greater innate immune system might render them actually more protected against COVID,” Dr Perrett said.
She is co-leading a new study at MCRI called COVID and You, which will be following more than 2,000 children and their family members to try and understand why they appear to be less susceptible to infection and severe disease than adults.
5. What about the cases of kids with Kawasaki disease-like symptoms?
Kawasaki disease is not new and we really don’t know what causes it, Professor Collignon said, but it appears to be triggered by certain infections.
It’s very rare, but the more prolific a virus is that triggers it, the more you’ll see of it in a given population, he said.
“So that’s why we probably haven’t seen it in Australia, but they have seen it in London and New York because they’ve got uncontrolled viral spread of this particular virus.”
However, not all the children with Kawasaki disease-like symptoms have tested positive to COVID-19, suggesting it’s probably too early to make a definitive link between the two.
“We need to be concerned because it can be a serious disease, but … we need more data,” Professor Collignon said.
6. Should I be sending my child back to school?
For kids going back to school their risk of infection is low, Dr Short said.
The changes we’ll see in schools, such as physical distancing and increased hand-washing, will be more to protect teachers and parents.
“At the end of the day, if I look at school outbreaks in Australia and elsewhere, the major factors have been the adults at the school,” Professor Collignon said.
“What I think is really important is that we actually make sure the adults associated with schools, they keep the physical distancing, they keep the crowds down, they keep the hand hygiene up.”
A few small studies have shown somewhat promising results that kids who are immunocompromised don’t necessarily seem to be at a heightened risk of severe COVID-19.
But Dr Short cautions we need to wait until results are available from larger studies to have a better idea if this is the case more broadly.
For families who have an immunocompromised member at home, deciding whether or not to send your child back to school could be a harder decision.
“This is the whole moral of the story, I think, with COVID-19, it is not one size fits all,” Dr Short said.
“The bottom line: we can never have zero risk with this. This is here to stay for quite a while,” Professor Collignon said.
“We have to make the risk as low as is reasonable with the constraint that we can’t all become hermits for the next two or five years.”
Source: ABC News