Schools could be closed for up to three weeks while non-deadly spiders are dealt with

Four schools in east London have been closed because of infestations of false widow spiders.

The creatures, which have a body length of between 8.5mm and 11mm and resemble the far more dangerous black widow, have been found at two primary and two secondary schools in Newham.

A bite from a false widow can be painful and cause redness and swelling, according to the NHS.

Rokeby school in Canning Town will remain closed until 29 October, its headteacher, Charlotte Robinson, informed parents and carers in an email. “The safety and wellbeing of students and staff must be our priority, so whilst I understand that this may be very inconvenient for you, it is in your child’s best interest to remain at home and not at school,” she wrote.

Robinson said a company hired to eradicate the pests had advised that the process would take up to three weeks. The schools have been told treatment is necessary before eggs start hatching.

Sue Ferguson, the headteacher of Ellen Wilkinson primary in Beckton, told parents the school would be closed this week and for most of next week. Lisle Von Buchenroder, the headteacher of Star primary school, said an update on when it would reopen would be made next week and the possibility of using alternative venues was being explored.

Lister community school in Plaistow was the most optimistic: its headteacher, Anthony Wilson, told parents he hoped to reopen on Friday. “These spiders can bite humans and the bite is unpleasant, although it is very rarely serious … There have been no reports of anyone at Lister being bitten by a false widow spider,” he said.

There are different types of false widow. The school infestations are of noble false widows (Steatoda nobilis), which are the most commonly reported of the species.

False widows are believed to have arrived in the UK in 1879 in a bunch of bananas from Madeira and they are one of about a dozen species capable of biting humans, out of the UK’s 650 spider species.

About one-third of bites cause nausea, headaches and lethargy. No one has been recorded as dying from a noble false widow bite.

In 2015, two schools in Tower Hamlets, which neighbours Newham, were closed due to infestations of the spiders.

Buglife, the invertebrate conservation charity, said the decision to close the schools was a “radical and unnecessary overreaction to the tiny risk posed”, claiming that the use of insecticides “may be a higher risk”.

They said the spider’s bite “can cause localised pain, minor swelling and, in extreme cases, nausea. Within a few hours of a bite, symptoms then fade away”. But they said there were “no proven cases where the noble false widow bite has caused death, coma or permanent injury”.