In the Island’s biggest day of coronavirus testing since the Covid-19 pandemic began, the six boards of health reported three new antibody cases and three new symptomatically positive patients on the Vineyard Thursday, bringing the total coronavirus caseload here to 45.

And as testing has ramped up on various fronts and hit at least one milestone on the Island, no new laboratory confirmed cases were reported Thursday.

To date the Island has had 30 patients test positive for the virus via a PCR swab test, with 28 of those tests conducted at the hospital and two conducted off-Island.

Added to that, 15 patients have now been identified as probable cases on-Island. Those patients include 12 who have received a positive serology test for viral antibodies. Three new antibody cases were reported Thursday. Antibody testing is only available off-Island.

Also Thursday the boards of health reported three patients as symptomatically positive. The report stemmed directly from a change in the state Department of Public Health’s reporting recommendations, Tisbury health agent Maura Valley said.

In an email later, Ms. Valley said the three new patients were no longer symptomatic. “They are older cases that were added to the probable case count as a result of the state’s change in reporting criteria,” Ms. Valley said.

There are now two testing facilities on the Island: at the Martha’s Vineyard Hospital, which only tests symptomatic patients and their close contacts, and the new comprehensive testing site at the regional high school which opened to the public Monday.

The hospital, which began testing in March, passed the 1,000-patient mark this week for numbers of tests performed. As of Thursday the hospital had tested 1,013 patients, with 28 positives, 949 negatives and 36 pending.

No one is currently hospitalized with the virus.

Thursday unofficially marked the biggest day of testing yet on the Island, with 77 patients receiving tests at the new testing center at the high school and another 40 or so getting tested at the hospital.

The new testing site at the high school, available to all by appointment, had tested 240 people for Covid-19 by Thursday afternoon. Of those, 115 have come back negative and 125 are pending. All the patients tested to date are considered high priority Islanders, including public safety officials, grocery store and other essential employees, and health care workers.

The testing site at the high school is a public-private partnership between Quest Diagnostics, Island Health Care and the six boards of health. The site opened to the public on Monday.

A spokesman for the project said they had received 360 calls for tests as of noon Wednesday.

To schedule a test, call 1-877-336-9855. High-priority patients will be scheduled first.