Forty-six people at Camp Michawana have tested positive for COVID-19 and another seven are considered probable cases.
The Barry-Eaton District Health Department confirmed the updated numbers Friday.
The camp had six cases and one probable case last week, including five staff members and one camp visitor.
About 250 people were exposed to the virus, the health department said last week.
Those who attended or stayed at Camp Michawana on or after July 24 may have been exposed. They were told to self-quarantine at home for 14 days past the last date of their stay at camp and seek testing immediately if symptoms develop.
The camp is currently closed to all visitors.