There are many examples in the records of Victorian schools of the dangers of disease.
When illnesses such as diptheria, measles and whooping cough spread very quickly to many people in a community it was called an 'epidemic', and these were very common in Victorian times.
Schools were often ordered to be closed to try and control the spread of the illness among the local families.

This is just one case, and it comes from the Log Book of Nantmel St Mark's School at the very end of the Victorian period, 1901 :
"School reopened today after being closed for two months. Should have recommenced on the 26 Aug[ust] but could not do so on acct [account] of an Epidemic of Whooping Cough amongst the children".

Because serious diseases were so common in these times, there are also many references to deaths in the school records...

Sickness, fever, and funerals...