As the Vineyard experiences its first surge in coronavirus cases, the Martha’s Vineyard Hospital and Island boards of health put out a joint statement Sunday, calling urgently for renewed vigilance and strict safety protocols to stem the possibility of community spread on the Island.

The Island reported 18 coronavirus cases this past week — the most in a single week since the pandemic began.

Issued early Sunday morning, the statement by the hospital and health agents was cast in the most serious tones, calling the 18 new cases — 10 more than any previous week on-Island — a case surge and a disturbing trend. Health officials urged all Island residents and those planning to travel to the Vineyard to maintain strict public health guidelines to avoid exposure.

“These high numbers should be viewed for what they are: a stark warning to all of us that we are not out of the woods and every one of us remain at risk for infection,” Tisbury health agent Maura Valley said in the statement. “We need people to be vigilant about the protocols to avoid exposure and if they are exposed or receive a positive test, to cooperate fully with our contact tracers.”

Ms. Valley is the leading spokesman for the six Island boards of health.

Coronavirus cases are surging again around the state, country and in Europe, on the eve of the highly-charged presidential election.

The recent case surge on the Vineyard and subsequent statement come after a case cluster was identified early last week that health agents had traced to a private wedding held over Columbus Day weekend on the Island. Ten cases have been traced to the cluster, eight of which remain on-Island and in isolation. Five of the cases involved workers at the wedding, and a recent case was traced back as a contact of a guest.

But in the statement Sunday, health officials and the hospital said only five of the 18 new cases reported this week are connected to the cluster, sparking concern that the Island may be experiencing broader spread of the virus in the community.

“This current uptick in cases should serve as a reminder to the community to avoid large gatherings, and always wear a mask when out in public when physical distancing is not possible,” the statement said. “Contact tracing and case investigations are underway, with close contacts of positive individuals being quarantined and referred for testing. Although five of the new cases are linked to a cluster connected to an Island wedding, most are not. The concern is that the Island could be experiencing the beginning of community transmission.”

Eleven of the 18 new cases last week were tested at the hospital, according to the statement, while the other patients received their tests at TestMV. The hospital is testing symptomatic patients for the virus and their close contacts, while TestMV is focused on asymptomatic testing.

The statement also urges Island businesses to review their Covid-19 safety procedures with employees and ensure that physical distancing and masking is enforced in all shared work vehicles, break rooms and other public locations. Employees experiencing symptoms should be immediately referred for testing, the statement also said.

In the statement, health agents and the hospital provide a list of actions that they are requesting Islanders follow in order to prevent further disease transmission, including avoiding crowds, wearing a mask, respecting physical distancing, washing hands frequently, getting tested if you are a known contact, and following travel guidelines.

Individuals who attended the wedding over Columbus Day weekend violated state travel protocols, according to health agents.

The hospital and health officials warned that the current case surge could put Martha’s Vineyard in a high risk community classification if it continues, potentially leading to further lockdown measures, transitions back to remote learning and stricter gathering rules, among other things.

“Although Martha’s Vineyard is not currently classified as a high risk [red] community for Covid-19 transmission by the state of Massachusetts [based on average daily cases per 100,000 residents], this current surge has the potential if it continues to push us into that classification. To bring this current surge in new cases of Covid-19 under control, we need the entire Island to work together to keep cases down. We urge everyone in the community to stay vigilant,” the statement said.

Complete text of statement from boards of health, hospital.