Extra staff is working overtime in Hawaii to find the cause of a Hepatitis A outbreak that has grown six-fold since July 1, but state officials admit they are stumped.

People who have recently been exposed to Hepatitis A and who have not been vaccinated previously should be administered a single dose of single-antigen Hepatitis A vaccine as soon as possible, within 2 weeks after exposure, according to the CDC. The average incubation period for Hepatitis A is 28 days, but symptoms can appear 15 to 50 days after exposure. (Photo courtesy of the CDC)
People who have recently been exposed to Hepatitis A and who have not been vaccinated previously should be administered a single dose of single-antigen Hepatitis A vaccine as soon as possible, within 2 weeks after exposure, according to the CDC. The average incubation period for Hepatitis A is 28 days, but symptoms can appear 15 to 50 days after exposure. (Photo courtesy of the CDC)
Despite not having any hard leads on the source of the outbreak, State Epidemiologist Sarah Park said Tuesday that federal officials assisting with the investigation have praised the Hawaii public health efforts. “The CDC said ‘your epidemiology is spot on, it’s only one outbreak,’ ” Park said, explaining that all of the samples Hawaii has sent to the Centers for Disease Control and Prevention for DNA sequencing have showed the same strain of Hepatitis 1A. “Unfortunately it’s a unique strain that isn’t in their database. They can’t find a match for it from any previous outbreaks. … We haven’t been able to develop a hypothesis so we can’t do a case control study.” Without a case control study, Park said it is virtually impossible to determine the cause of the outbreak. The only common denominator so far is that the outbreak appears to be limited to the island of Oahu.
Map of Oahu
As of July 26, employees of three restaurants in central Oahu (outlined in green) were confirmed as being among the victims of a Hepatitis A outbreak.
Three employees of restaurants on the island have been identified as outbreak victims, which raises the possibility they could have exposed customers. However, Park said, the employee illnesses should not be interpreted by the general public as a sign that any of the three restaurants is the root source of the outbreak. As of Tuesday, 93 people have been confirmed with the outbreak strain. A third of the patients, 29, have required hospitalization since June 12 when the first person fell ill. The most recent person became sick July 21, indicating the outbreak is definitely ongoing. Park said the usual 30- to 70-day incubation period for the infection complicates investigation efforts because patients usually don’t have complete memories of everything they ate and drank back that far. But she is hopeful that one recently confirmed case will help narrow the investigation. All of the 93 confirmed victims were on Oahu during their exposure period. Four of them now live on the islands of Hawaii, Kauai, and Maui. One of those four is considered an “outlier” case, Park said. “We have one person with a very narrow possible exposure window, and that should help. It’s more likely we can narrow down what and where they ate,” Park said. The three restaurants that have each had one employee sickened in the outbreak, and the dates those employees may have exposed restaurant customers, are:

  • Baskin-Robbins on Oahu at the Waikele Center with possible exposure dates of June 17, 18, 19, 21, 22, 25, 27, 30, and July 1 and 3;
  • Sushi Shiono on Hawaii at the Waikoloa Beach Resort — Queen’s MarketPlace, 69-201 Waikoloa Beach Drive, with possible exposure dates of July 5-8, 11-15, and 18-21; and
  • Taco Bell on Oahu in Waipio, 94-790 Ukee St., with possible exposure dates of June 16, 17, 20, 21, 24, 25, 28, 29, 30, and July 1, 3, 4, 6, 7, and 11.

Park said all three restaurants have “green” ratings in terms of health inspections, which is the best rating under the state’s green, yellow, red rating system. Anatomy of the investigation Between 20 and 30 employees of Hawaii’s Department of Health are working directly on the outbreak investigation, though not all of them are on it full time every day, Park said. She has pulled in staff from various divisions to help. Some employees are covering duties for coworkers who are assigned to the outbreak in addition to handling their own workloads. Dr. Sarah Park“We’ve got people working overtime on this,” Park said. The investigators are interviewing patients and then interviewing them again. “We’re really grateful to them (the victims) and their help, especially after the fourth or fifth time we call them back to ask more questions.” In addition to patients’ memories, public health staff is pouring over lists of debit card and credit card transactions the outbreak victims have provided. Store loyalty cards are also providing important details about what foods people ate and where they bought them. “The stores have been very helpful providing the data from the cards, but we are having to enter a lot of it by hand (into our system) so we can analyze it,” Park said. “We are also using tools like mapping programs that we have learned from other outbreaks can be helpful in developing a hypothesis.” An attorney representing two of the outbreak patients who required hospitalization met with the two people this past weekend. “They have offered continued assistance to the health department to locate the source of this potentially deadly virus,” said Seattle food safety attorney Bill Marler. (Marler Clark underwrites Food Safety News) “I encourage all the victims to reach out to the Health Department to provide, debit card and credit card statements, check registers, cell phone records, club card numbers, social media account information, and any other material that would provide data on where they were and what they ate or drank in the weeks before they became ill. “With this many people ill, there has to be a common link, it is just not apparent yet. I would also encourage the Health Department to reach out to the medical school to interview people and the computer science department to help crunch the data gathered from the victims.” Advice for the general public As the outbreak continues state and federal health officials are encouraging certain people to talk to their doctors about getting a “post-exposure prophylaxis” shot if they have not been vaccinated for Hepatitis A and are considered a “contact.” A contact is defined as someone who:

  • lives with an infected person;
  • has had sexual contact with an infected person;
  • has shared drugs or drug paraphernalia with an infected person;
  • has shared food, beverages or eating utensils with an infected person; or
  • consumed ready-to-eat foods prepared by an infected person.

The post-exposure, single injection of Hepatitis A vaccine or immune globulin — depending on the age of the person — must be given within two weeks of exposure according to Park and the CDC. Dr. Sarah Schillie, medical officer at the CDC’s Division of Viral Hepatitis, said Tuesday the post-exposure vaccination and immune globulin are known to be extremely effective at preventing the infection from developing, if people receive them soon enough after exposure. Most children have received Hepatitis A vaccinations as part of the standard battery of immunizations since 2006, Schillie said. Some adults also receive the vaccination before international travel. The vaccination before exposure involves two injections, that must be given six months apart. In general, Schillie said adults are not routinely recommended to receive the Hepatitis A two-shot vaccination unless they are in certain high risk groups, such as those traveling to certain countries and men who have male sexual partners. However, there is no general rule against adults receiving the two-shot vaccination, Hawaii’s Park said. Both Park and Schillie said people should talk with their doctors to find out whether they should receive the Hepatitis A vaccine regimen. Park said initial reports that there might not be large enough supplies of the post-exposure injections are turning out to be unfounded. The state has asked pharmacies to continue ordering and stocking the vaccine and immune globulin. A list of pharmacies that are offering the shots is available on the state health department website. “What I really want people to understand is that the vaccination and the (post-exposure shots) are both very, very effective and very, very safe, Schillie said Tuesday. Despite the effectiveness of the preventive, two-shot vaccination, both Schiller and Park said neither federal nor state public health officials suggest foodservice workers such as restaurant employees should be required to have the vaccination. Both cited the high turnover rate of restaurant employees as a stumbling block. “If a college student is working a summer job at a restaurant, they are done with the job and back at school and may never work in foodservice again,” Schillie said. “And since you have to wait six months between the two shots, it just doesn’t make since to require it.” Hawaii state law does require that foodservice workers who have not been vaccinated and who are “contacts” of an infected person must be tested and receive a negative result before returning to work after exposure. “Once an infected food handler has been identified, (Department of Health) staff coordinate directly with the owners and managers of the affected food service establishments to ensure their employees are tested before resuming their work,” according to the Hawaii health department website.. Knowing when exposure occurred isn’t always easy to determine, however. In addition to an incubation period of up to 70 days before symptoms begin, Hepatitis A can be spread during the two weeks before symptoms begin and for a week after a person falls ill. Symptoms of Hepatitis A infection include fever, fatigue, loss of appetite, abdominal discomfort, dark urine, diarrhea, and yellow skin and eyes.