Amid rising numbers of confirmed cases of Covid-19, Gov. Charlie Baker extended a statewide stay-at-home order to May 4 Tuesday, and a ninth confirmed case was reported on Martha’s Vineyard.

The Tisbury board of health reported the new case Tuesday afternoon. The patient has been “symptomatically” diagnosed with the virus, a press release said. Also a new reporting method from the boards of health breaks down confirmed cases by age group and gender.

Speaking to the Gazette by phone, Tisbury health agent Maura Valley, the designated spokesman for the Island boards of health, said the ninth patient is a person who had been diagnosed with Covid-19 but had not received a positive test.

In its own new daily briefing system, on Tuesday morning the hospital reported no new cases of Covid-19. And state numbers released late Tuesday afternoon still only indicate eight positive tests on the Island.

Explaining the discrepancy, Ms. Valley said the boards of health are treating it as a positive case because the person was symptomatic, even though the test came back as inconclusive.

“The doctor said they really believe this person was positive,” she said. “It was counted as a positive by us for contact tracing and follow-up purposes.”

Ms. Valley said Island boards of health are working closely with the hospital to begin contact tracing for symptomatic patients early on, even if tests did not come back positive.

“We are trying now to work with the hospital and Island Health Care to try to start capturing the people who are being clinically diagnosed and not necessarily lab diagnosed, because we want to do contact tracing with them,” she said.

She also said the patient was not a new diagnosis, but that she wanted to include the case in board of health numbers because it better reflects the number of cases they were monitoring on the Island.

The report released Tuesday by Island boards of health showed that of the nine cases being tracked on Island, four are male and five are female. Six cases are for individuals aged 50 to 59, with one case each in the 20-29, 30-39, and the 60-69 age range.

Governor Baker’s stay-at-home order, set to end April 7, has been extended by a month.

A stricter stay-at-home order, including town-by-town construction bans, is in effect on the Vineyard.

The decision to extend and strengthen the stay-at-home order came as the state reported 33 deaths on Tuesday, the largest single-day total since the outbreak began, bringing the statewide death toll to 89. The state Department of Public Health reported 868 new confirmed cases on Tuesday, bringing the total to 6,620 cases in the commonwealth.