In Wallonia (Southern part of Belgium), universities are already back to only giving online classes, schools will be closed two additional days after the Autumn holidays (so November 2-11), and secondary schools (12-18 years-old children) will be virtual for the 3 days before the Autumn holidays (so October 28-30). The reason? The exploding number of COVID-19 cases in schools.

In Wallonia, education is in the hands of the French-speaking Community (along with Brussels) but its statistics department doesn’t seem to provide public data on COVID-19. For that, we have to look at ONE (roughly: “Office for births and infancy“) that communicate weekly numbers of cases and quarantines in children in schools via press releases (forcing us to parse PDFs but it’s better than no data).

So far, the students in secondary school (12-18 years old) are the worst hit with a total of 6,258 positive cases since September 2020 (I’m writing this on October 27), followed by teachers and other personnel (total: 2,497 positive cases).

Is it a lot? Consider this: for the week ending on October 18, incidence in primary school (6-11 years old) is 365 / 100,000, incidence in secondary school (12-17 years old) is 1,117 / 100,000 while the average incidence over the last 14 days in the whole Belgian population is 1,289 / 100,000 (epidemiological bulletin of Oct. 26). Adolescents are therefore a driver of the incidence.

But one can see on the charts below that all age categories are exponentially seeing new cases:

Unfortunately, when you read the press releases, you realize that these numbers are minima. Indeed, the situation is actually worse but there are several reasons why numbers are not completely reported:

• Health services in schools are not staffed to face a pandemic, they were not prepared and now some personnel also got the virus.
• As a consequence, data is not completely transmitted to ONE since mid-October (it’s apparently worse for quarantine data, not shown here: at least 21% of cases don’t have data associated with potential follow-up quarantine in the last (7th) report).
• Since October 1st, protocols (quarantine decreased at 7 days, definitions of close contact, etc.) changed.
• Children below 6 years are exceptionally tested.
• Children between 6 and 12 years (primary school) are tested only if they meet some conditions (symptoms, contacts in the family, or if 2 cases in the class).
• It seems there are issues with reporting in students 18+ (“écoles supérieures“).
• Universities are not reported in this count.
• For adults (here: 18+ students, teachers and personnel), Belgium is back at testing only symptomatic patients since October 19, 2020.

So the additional days of holidays and making a few additional days of virtual school for secondary students is meant to try to break transmission of COVID-19 in schools.

Talking about transmission, it seems there is a kind of exploration on sources of infection in the ONE reports. It is not reported systematically nor in a similar way but the source of infection for reported cases is the school (close contact with a student, a teacher or a personnel) in 16-20% of cases.

I really hope this extended holidays will reduce transmission. It seems the younger a child is, the less symptoms he/she’ll display, it therefore seems ok for them to get the disease. But children remain important transmission vectors and we don’t want them to transmit the disease to more vulnerable groups of the population, like grand-parents but also adults and children with co-morbidities or immune diseases. Let’s not add a COVID-19 burden to the usual disease associated with winter (like flu).

To be continued …

As usual, you’ll find other graphs on my page about COVID-19 in Belgium (and figures above are updated with new data as they appear) and the data, code and figures are on Github (including the AVIQ one in this post).

• Data
• Health