A number of pupils at Bo'ness Academy, near Falkirk, are having to self-isolate due to a coronavirus outbreak amongst pupils.
But according to health bosses there is no evidence to confirm in-school transmission.
Parents were alerted by text message this week, which urged those in S5 to take a PCR test, as a 'precautionary measure'.
It also stated that cluster was due to three separate events pupils attended over the weekend outside of school property.
A spokesperson for Falkirk Council confirmed some pupils are having to self-isolate.
An NHS Forth Valley spokesperson said: "NHS Forth Valley’s Test and Protect team is carrying out Covid-19 contact tracing in Bo’ness Academy School after a small number of individuals linked to the school tested positive for the virus.
"There is currently no evidence of any transmission within the school and any close contacts have been identified and are self-isolating in line with national guidance.
"Robust control measures were already in place to protect the health of pupils and staff and the school remains open.
"Apart from those who have been identified as close contacts, all other staff and pupils are continuing to attend the school as normal.
