State health officials are bracing for the first potential cases of hepatitis A two weeks after a shipment of tainted ahi cubes was delivered to about a dozen Oahu grocery stores and food outlets.

While much of the 2,325 pounds of raw fish imported from Indonesia was retrieved uneaten by distributor Tropic Fish Hawaii LLC after laboratory test results indicated the shipment was contaminated, it was too late for an estimated 885 pounds that was sold and presumably consumed by customers between April 28 and May 1.

The symptoms of hepatitis A, a contagious liver disease, are known to appear about 15 days after exposure and as much as 50 days later, although the peak time for the sickness to turn up is about 30 days afterward, officials said.

Last year Hawaii experienced the worst hepatitis A outbreak in at least a quarter-century when 292 people were sickened after eating contaminated, imported raw scallops that were sold at Genki Sushi restaurants. Seventy-three people were hospitalized, and at least one died of complications that may have been related to the illness.

But this time officials are hoping that most, if not all, of those who consumed the product were able to get the hepatitis A vaccination after news of the contaminated shipment circulated across Oahu.

“This is highly unusual,” state epidemiologist Dr. Sarah Park said in an interview Thursday. “It’s the most ideal situation that we never see. We get to stamp out a disease before it even starts.”

Park, head of the state’s Disease Outbreak Control Division, didn’t want to predict how widespread the possible outbreak could become. But she did say she wouldn’t be surprised if only one or two cases emerge, perhaps from people out of touch with the news.

“I’m hoping they heard the message,” she said.

Park said it’s also possible tourists may have partaken — and carried the disease home with them oblivious to the hazard. The department might not hear about any mainland illnesses until colleagues there report it, she said.

Park said in Hawaii her staff will remain vigilant, keeping close tabs on the electronic reports her division receives from the state’s major clinical laboratories.

Area doctors and clinics are also being encouraged to report any cases that arise.

“No clinician is going to miss reporting hep A after what happened to us last summer,” she said.

It was July 1 that state health officials first alerted the public to a mysterious cluster of hepatitis A cases. It took a month and a half of epidemiological sleuthing, but officials finally found the source — raw scallops imported from the Philippines — and shut down Genki Sushi restaurants on Oahu and Kauai for a month.

During the uncertainty of the 2016 outbreak, tens of thousands of people were vaccinated for the disease.

In the current incident the source is already known. The frozen fish was delivered to Times Supermarkets in Aiea, Kailua, Kaneohe, Kunia, Liliha, Mililani and Waipahu, and at Shima’s Supermarket in Waimanalo. It was also distributed to GP Hawaiian Food Catering, Maili Sunset Bar &Grill (aka Da Crawfish &Crab Shack) and the ABC Store at 205 Lewers St. in Waikiki.

When the distributor found out about the test results, it notified the Health Department and affected food outlets, then retrieved as much of the fish as it could.

While Tropic Fish Hawaii blundered in delivering the fish despite a Times Supermarket policy that it be tested first, Park said the distributor should be commended for owning up to its mistake immediately. Otherwise, she said, it could have blown up into another major outbreak that lasted weeks or even months.

Instead, officials notified the media, and Hawaii’s medical clinics were alerted so they could have plenty of hepatitis A vaccine on hand.

For now it’s a waiting game for health officials to see whether anyone gets sick.

“Hopefully this all goes away,” Park said.

Bill Marler, a Seattle attorney who represents 85 people who were sickened in the 2016 epidemic, maintains Hawaii will likely escape a wide-ranging outbreak.

In researching his Hawaii cases, the firm subpoenaed vaccination records from Hawaii’s largest insurance companies, Marler said. The records indicated that nearly 100,000 people received shots from July to October.

“Hawaii is probably the most vaccinated population in America now,” he said.

Park said that while she didn’t have any precise numbers, demand for the vaccine in Hawaii was unprecedented — enough to decrease the supply across the nation.

Park, the state’s top disease specialist since 2008, said the latest incident is actually a “win-win” for Hawaii. Even more people sought protection against hepatitis A over the last two weeks, and others who already did were reminded that it was time to get the second shot to ensure lasting immunity.

“If it means we’re highly vaccinated against hepatitis A, it’s all the better,” he said. “We might not see an outbreak in a while.”

Anyone who suspects they are even remotely vulnerable — having eaten poke the last weekend of April, for instance — should consider getting a vaccination now. Clinics report plenty of vaccine available.

Symptoms of hepatitis A include fever, fatigue, loss of appetite, abdominal discomfort, dark urine, diarrhea and yellow skin and eyes. Officials say food service employees or anyone else showing symptoms should stay home and contact their doctor.

While a series of two vaccinations provides the best protection, frequent hand-washing with soap and water after using the bathroom or changing a diaper can help prevent the spread of the disease. Cooking food thoroughly can also help to prevent infection, officials said.

In related news, health officials announced Friday that three new mumps infections are being treated on Oahu, bringing this year’s total to 30 confirmed cases.

Officials said the department is investigating a cluster of cases linked to the Job Corps Center in Waimanalo. Those who came into contact with the individuals during their infectious period are being notified, they said.

The department said it is working closely with the Job Corps Center to monitor all program participants and staff to identify, control or prevent additional cases.