Coverage Care, which operates homes in Telford, Shrewsbury, Bridgnorth, Oswestry, Whitchurch, Bishop's Castle, Newport and Market Drayton, said it is going "further than official advice demands" and is taking the situation more seriously than anything it has previously seen.
The company will remain open for admissions and visits from health and social care professionals as well as urgent suppliers, but is now actively discouraging all visitors including family and friends of residents.
Plans are also being made to use technology, including video calls, to keep people in touch and support other normal activities.
The news came as the UK death toll reached 35 on Sunday and the number of confirmed positive Covid-19 cases passed 1,300.
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The Government has not banned care home visits but on Sunday the Health Secretary urged anyone over 70 to self isolate for four months.
Infection control measures, visitor and staff screening and enhanced staff training are all now in place at Coverage Care, while steps to manage staffing in the safest possible way are being prepared in the event of a more widespread outbreak.
Chief Executive for Coverage Care, David Coull, said: “We fully understand that no one wants to be cut off from their loved ones, especially at a time like this, but we have a huge responsibility to an often highly vulnerable group in our community and have to take this threat more seriously than anything we have ever faced. The protection of the people in our care and of our staff is our first and over-riding priority at this time.
“We do appreciate our measures are currently going further than official advice demands, but we are acting out of an abundance of caution having seen that this virus can appear in the least expected places.
"We will continue to make the most strenuous efforts to protect everyone, while understanding that this will be a difficult time for many.”
Mr Coull added that "clear advice" on the impact of visitors will be given to anyone who goes against their "strong recommendation".
“While no relatives and friends are at this stage being actively barred from entering the homes, we are asking people to act responsibly and support us in keeping their loved one safe," Mr Coull said.
"We are also asking for their understanding that we are only doing this with the very best motives in mind and we ask for their patience and to stay away while we get through this extremely difficult phase containing the spread of the virus.
"Anyone who does insist on entering the premises, against our strong recommendation, will be given clear instructions and advice on the impact of their action and movements while in our home.”