Harris Academy Merton has confirmed a member of staff tested positive with coronavirus last week.
The school located on Wide Way in Mitcham sent a "small number" of children home to self-isolate for 14 days.
On October 8, the school informed parents that their children had been in "close contact" with the person infected.
Harris Academy Merton confirmed a member of support staff is now at home with "mild symptoms".
MORE: Coronavirus test centre opens at Merton College
Headteacher Ms A Samad informed parents in a letter which stated:
"Unfortunately a single member of our support staff has tested positive for coronavirus and is now at home with mild symptoms.
"This is a single, isolated case that we are treating with a great deal of care. We are liaising closely with Public Health England to ensure we are responding appropriately.
"We have informed the parents of the small number of children who have been in close contact with the individual who has tested positive for Covid-19.
"This is a very important time of the year for students as they settle into their new year groups and routines, so we are grateful for your cooperation in ensuring that all students who are feeling well attend school."
Has your school been affected by Covid-19? Contact us at monica.charsley@newsquest.co.uk
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