Shropshire Council said it expects the number of positive Covid-19 cases to rise in the coming days after two cases were confirmed at Craven Arms last week.
The infections were linked to an outbreak in Welshpool at a recent local event.
The local authority and Public Health England set up a testing site at a nearby business park on Saturday. As of Sunday 41 people from the caravan site have been tested.
All residents on the caravan site have been asked to self-isolate with members of their households for two weeks following contact with someone who was tested positive for the virus.
Councillor David Evans said the local authority is working closely with the NHS, Public Health England and local police to provide up to date guidance on the outbreak.
“Our priority is to protect the health and wellbeing of our local residents," he said.
"I’ve been in Craven Arms to talk to residents and businesses to answer any questions and reassure them that the risk to the general public is low.
“I would like to thank members of the community for their own ongoing support and co-operation.
“We continue to rely on everyone at the site playing their part, and want to encourage the residents to continue to self-isolate and take all the necessary precautions. This is the only way we can help stop the spread of the virus.
“As we now have a test site in the town, if anyone is having symptoms, I would strongly encourage them to book an appointment either online or by calling 119. Anyone concerned can book an appointment.”
Shropshire Council said essential items including fuel have been delivered to the site and a playground and outdoor gym in Newington Way has been temporarily closed to help reduce transmission of the virus.
Personal Protective Equipment (PPE), hand sanitisers and cleaning products have also been distributed on the site.