The amount of bacteria in primary schools is at a high enough level to cause sickness, according to new research.
A study found that play equipment, chairs, door handles, door frames and radiators all contained bacteria levels that were higher than what is considered normal.
Rentokil analysed bacteria levels in a large south of England primary, swabbing over 140 sites.
The readings were analysed using an ATP bioluminescence reader. A reading of over 500 units on an object indicates a high level of contamination, whereas 200 to 500 is considered normal and under 200 is low.
The top five areas of high bacteria recorded were play equipment at 7,479 units (15 times higher than what is considered normal), chairs at 1,647 units (three times higher), door handles at 1,358 units (almost three times higher), door frames at 1,236 units (more than double) and radiators at 858 units (almost twice what is considered normal).
The hands of 175 children aged four to 10 have also been swabbed by Rentokil over the last 12 months. A high reading is considered anything over 2,000 units on hands. These results showed an average reading of 2,283 units, with one child's hands reading 9,999, almost five times the amount considered normal.
Luke Rutterford, technical manager at Rentokil Specialist Hygiene, said: "Sporadic cleaning, coupled with ineffective handwashing by children, means that bacteria and other microorganisms can be spread more easily between children at school.
"In the winter months, schools are at an increased risk of Norovirus outbreaks and so it's even more important that proper hygiene practices are followed.
"The high readings on the areas we swabbed at the school are cause for concern because there is an obvious risk of cross-contamination from one individual to another, which can lead to infection and sickness outbreak in the school environment."