There are now 20 confirmed Covid-19 cases in the Bailiwick, which is an increase of 18 known people with the virus since Friday.

About 1,000 islanders are in compulsory self-isolation and the next seven days have been described as ‘critical’ in the fight to halt the spread of the disease.

In a candid appeal to all islanders, the president of Health & Social Care, Deputy Heidi Soulsby, laid bare the severity of the situation. ‘We only have one hospital and a small health and care infrastructure.

‘The behaviour of our community will either protect that infrastructure or bring it to its knees.

‘We cannot send patients off island as UK hospitals are full. No single member of our hospital services team wants to be in a position where we are having to decide who to treat because of a lack of resources.

‘Everyone absolutely must work with us and pull together as a community to prevent the spread of Covid-19.’

On Saturday night, the number of positive cases went up to 17, and at that time the public health team reassured the community that all of those cases had a clear travel history, the individuals recently returned from the UK, France, Tenerife, Spain, Germany, Austria and Switzerland.

Health officials identified ‘four clusters’, or four groups of families and friends, among 10 of the confirmed positive cases.

These four groups had been on ski trips in France, Germany and Austria.

Up until tonight [Sunday], none of the cases appeared to have been acquired locally, so there was no evidence of on-island spread and it meant the island remained in the phase of its emergency plan called ‘containment’.

This evening, a further three cases of coronavirus were announced, and further information on those is likely today.

In total, 341 tests have been taken locally, with 259 negative results and 62 still awaiting results.

Last week the States introduced stringent measures to stop the spread of the disease, including closing the borders to non-essential travel, shutting schools and nightclubs, and calling time on pubs that do not serve plated food.

Following the increase in confirmed cases, Deputy Soulsby indicated that more restrictions could be on the way.

‘These are not the last difficult and impactful decisions we will have to make whilst we fight to protect our community from Covid-19.

‘It is essential that people listen to the advice we are issuing regarding hand washing, social distancing and self-isolation.

On Saturday night, the island’s most senior politician, Deputy Gavin St Pier, outlined that the increase in confirmed cases was expected, but it was at least encouraging that there was no evidence of so-called community seeding.

‘Let’s be clear, we know and have always known that we will have more positive cases in Guernsey but the good news is we have no cases of transmission within the community and so remain in the ‘‘contain’’ phase of our plan.’

Over the weekend the public health team was carrying out ‘contact tracing’, which means tracking down people who have been in close proximity with the infected individuals, such as on aeroplanes.

This work is said to be ‘progressing well’.