A new strain of the COVID-19 virus that has the ability to reinfect people who survived it before is now present on Oahu, state health officials said Friday.

The Brazil strain — the second of two that originated there and is being monitored as having worrisome mutations — has been tied to infections across the U.S. and in Europe and was found in one Oahu patient who recently traveled to the mainland.

The discovery was made by the Hawaii State Laboratories Division, where scientists analyze about 7.8% of all COVID-19 tests collected in the islands, or about 75 specimens per week, in search of variants that international scientists have flagged as concerning.

“It is remarkable because it has a mutation associated with reduced effect of antibodies,” Dr. Edward Desmond, Hawaii State Laboratories Division administrator, said at a press conference Friday. “If people form antibodies in response to a vaccine, those antibodies might be less effective in neutralizing the virus and protecting us.”

Desmond noted that scientists are still investigating how the strain’s mutations resist antibodies. Scientists are confident COVID-19 vaccines still prevent serious illness and death, he said.

“Notice I say less protective. I didn’t say not protective, so we still have some hope,” he said.

The state’s vaccine campaign is still “critically important,” said Dr. Sarah Kemble, Hawaii state acting epidemiologist, who noted the Johnson & Johnson vaccine may soon receive federal emergency use authorization that could boost vaccination efforts across the nation.

Meanwhile, another COVID-19 strain that is now dominant in California is circulating in Hawaii and is most prevalent on Maui. The strain is believed by scientists to have contributed to a holiday wave of cases in California and may now be connected to a recent uptick in COVID-19 cases on Maui, where it has been confirmed in 28 specimens. Another 17 specimens have been detected on Oahu, as well as four on the Big Island and one on Kauai.

A third COVID-19 strain that originated in the U.K. has affected six patients from two households to date, but has not been linked to any other cases yet, Kemble said.

Oahu In A ‘Good Place,’ While Maui Records Case Uptick

The news of the latest variants comes as Oahu relaxes some capacity rules at gyms, restaurants and retail shops under new Tier 3 rules. Honolulu fitness facilities are now allowed to operate at half capacity, compared to 25% under the former rules. Group fitness classes may now include up to 10 people indoors.

If cases continue on a downward trend, Oahu could move to Tier 4 as soon as March 25, Mayor Rick Blangiardi announced this week.

“I think we are in a good place right now on Oahu, but if we see more of these strains in association with the variants then that would be a reason to go back and reconsider,” Kemble said. “If we are heading in the wrong direction, we can adjust for it.”

Still, the California variant could be playing a role in the recent uptick in cases recorded on Maui, Desmond and Kemble told reporters.

About 4.7% of people tested for the virus in Maui County had positive COVID-19 results this week.

Several Maui clusters are currently under investigation by the health department, including an outbreak at the Maui Community Correctional Center which has led to 31 diagnoses, according to the Hawaii Department of Public Safety.

Another Maui cluster is associated with a cleaning service. State investigators believe carpooling played a role. Infections have been confirmed among 16 colleagues and four of their household or family members. Another three people infected were associated with the same unspecified Maui travel industry site, according to the state’s weekly cluster report.

Another cleaning service on Oahu reported three infections this week. And an Oahu party led to 17 COVID-19 infections, according to the report.

Lessons Learned

A new Centers for Disease Control and Prevention study co-authored by Hawaii state epidemiologists offers some lessons about the virus’ transmission.

The study’s authors analyzed a chain of infection that began last summer with one fitness instructor and spiraled to involve three Oahu fitness centers, another instructor and 19 participants of yoga, cycling, personal training and kickboxing classes.

Researchers found mask-wearing did not prevent participants from contracting the virus while exercising indoors, and that teachers shouting instructions to participants could have played a role.

The CDC study’s authors encourage indoor gym-goers to keep a mask on and a six-foot distance from others working out in the same room.

COVID-19 cases among younger people continue to surpass other age groups in Hawaii. The majority of infections have been among people 18-29 years old, accounting for 24% of cases to date, and people 30-39 years old, accounting for 18% of cases. Only 8% of COVID-19 infections since last March have been among people 70 and older, yet the share of COVID-19 fatalities is largest among seniors.

The state is currently prioritizing essential workers and people 75 and older for the vaccine. About 60% of the 75-and-older population has received at least one dose.

As of Thursday, Hawaii had administered 336,901 vaccine doses. About 14% of Hawaii’s population has received at least one dose, with at least half of them getting two doses, according to the health department.