Kids catch coronaviruses.

Quick thread of a review article about two cold coronas that we knew about in 1974 when this article was written.

The article also says CoVs are airborne and also that kids would have milder presentation.

"frequently infect small children and reinfect adults"

Serology that indicated mouse hepatitis antibodies found in children was later found to be indicative of coronavirus strains.

"activity in all age groups, including children under five years of age"

they tested kids

kids had the highest infection rate

Studies looked at antybody prevalence and found kids started getting antibodies to cold coronas in the first year of life. By year 3, half had antibodies. 69% of adults did.

"the high incidence of infection ... in all age groups [indicates how often we must be reinfected]"

CoVs found coast to coast in US.

Found in Britain.

Documented 229E strain in Brazil in children. Antibody titre rose in the children when they were infected.

OC 43 strain periodicity in children (5th down).

Students is 1st.

All ages catch OC43. High rates in children (1st two lines).

"relatively uniform for all age groups ... this finding very different from RSV where [OLDER people catch it less]"

We don't see 229E in kids probably because serology isn't sensitive enough. (last lines - all p246)

**Quick detour while I am posting this:

This 1974 review article noted straight up airborne transmission, which I have been saying since March when I pulled reviews and read this.

It's right there, folks.

Children catch it.

No clear evidence they catch it worse.

In fact, they seem to exhibit milder cases (bottom), and there is a continuum of severity (children get milder cases than older).

Conclusion:

We need to study these viruses and develop the tools to do so.

They are a cause of significant respiratory illness and _even if you ignore they might cause significant illness in children_ (which they do) they are still important to study.

Here's an old post about airborne, referring to this review and others: https://twitter.com/jmcrookston/status/1277328161659854848

Since the 70s review articles have consistently said that coronaviruses are caught by, and transmitted by, children. They often show milder course of illness and are asymptomatic. Why we need to re-learn this is beyond me.

Separately, from Wuhan, January 2020 and re SARS2:

"This study showed that Covid-19 occurred in children, causing moderate-to-severe respiratory illness, in the early phase of the SARS-CoV-2 outbreak in Wuhan and was associated with ICU admission in one patient"

From Feb 2020, study of Japanese evacuees:

"In addition, children and young people may be a reservoir for asymptomatic, mildly symptomatic or pre-symptomatic transmission. In one family cluster, an asymptomatic 10-year-old child had pneumonia on a chest CT scan.13"

So we can argue how much they transmit, or how sick they get, but this idea that there will be no infections or no sickness is simply magical thinking.

I am tired of the magical thinking.

Magical thinking does not bring you a pony for Christmas.

From 1974 Monto, review articles about coronaviruses:

"Because of the limited period of viral activity it was possible to compare illness rates of those infected with persons not infected matched by age and sex; it was estimated that 45% of the infections had produced clinical

disease. Thus in the population, the rate of 229E-associated illnesses during the outbreak was 15 per 100 persons studied. Clustering of infections in family groupings were apparent as was activity in all age groups, including children under five years of age (16)."

"Children under 10 years of age exhibited lower mean antibody titers than older children or adults (16, 42)."

"Of special interest was the fact that children under five years of age had the highest infection rates (49)."

"Surveys of antibody prevalence have been conducted in several settings using OC43 antigens. McIntosh el al. found that children began to acquire antibody to this virus in the first year of life. By the third year of life, more than 50% had antibody present. Among adults, 69% of

"All age groups are involved in infection with OC43 virus. High rates have been noted in children or adults during studies separately examining both groups. In the Tecumseh study, a total population group was followed. During the 1968-1969 outbreak, infection rates were

relatively uniform for all age groups, varying from a high of 29.2 per hundred person-years in the 0-4 age group to 22.2 in those over 40 years of age (49). This finding is quite different from the situation that exists with other respiratory agents, such as respiratory

syncytial virus, where a more distinct decrease in infection rates can be observed with increase in age (48)."

Monto 1974. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2595130/

That little post I linked to from June 23 says this:

Cold CoV study from 70s. You can find other studies. children are certainly infected at rates comparable to adults, although often less symptomatic. SARS2 could be same

"Of special interest was the fact that children under five years of age had the highest infection rates (49)."

And if anyone says that kids don't spread it, or get seriously sick, they are making that up. We have 60 yrs of experience with the more minor CoVs to help us with this one. How they act should be the default until proven otherwise, not "this is totally new we know nothing".

Search pubmed for review articles by Monto, Robb, Bond, Tyrell, Siddell, and Mahy. Sorry no time to post the links

Again this thread from Monto 1974 the _earliest_ one (CoVs only discovered to be a "family" of viruses in 1968) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2595130/

Posted some of the review articles now, over here: https://twitter.com/jmcrookston/status/1310275748108922881