This week’s cluster report from the Hawaii Department of Health focuses on COVID-19 outbreaks at a restaurant chain, as well as one caused by a food supply delivery by an infected person, and a gathering at a karaoke bar.

Health officials say the risk among food service and restaurant workers has grown due to the highly transmissible delta variant — which now accounts for almost all COVID cases in Hawaii – combined with work environments that tend to be small and poorly ventilated and low vaccination rates among employees.

In July and August, health officials investigated two clusters with 40 coronavirus cases at a large restaurant chain on Oahu — with one location in a tourist area and the other in a community with low vaccination rates.

At one, 24 out of 29 exposed employees tested positive for COVID. At the other, 12 out of 24 exposed employees tested positive.

Most of the staff was unvaccinated, but eight of the employees that tested positive were fully vaccinated. Another four cases were spread to unvaccinated household members by employees.

In August, a food supplier who was infected with COVID dropped off a delivery at a restaurant on Oahu. Five out of 21 restaurant employees got infected. Two of them were vaccinated, or breakthrough cases. One household member of an employee also got infected.

This restaurant, officials said, had tight working spaces and poor ventilation which probably contributed to the spread of COVID-19.

But even fully vaccinated individuals should take precautions, which is the cautionary tale of an outbreak among 12 vaccinated food service workers who got together at a karaoke bar.

Also in August, 12 fully vaccinated employees sang together at a karaoke bar, considered a high-risk activity, with no masks or social distancing. Seven tested positive.

“Vaccination reduces but does not eliminate the risk of becoming infected and transmitting COVID-19 to others,” said officials in the report. “Everyone should take precautions to prevent COVID-19, including masking in indoor public places.”

Starting Sept. 13, Honolulu County’s Safe Access Oahu program goes into effect, requiring all employees, contractors and volunteers of places such as restaurants, bars, gyms, and museums, and their patrons, to show proof of full vaccination against COVID-19 or a negative test.

Officials said these policies will help protect the community, but that employers should also encourage and provide incentives for all employees to get vaccinated.

“High vaccination rates make workplaces and communities healthier and safer for everyone,” officials said.

The Hawaii Restaurant Association, meanwhile, is gathering testimony from members about the adverse impacts of the program on restaurants.

In all, officials are actively investigating a record high of 70 clusters in all four major counties involving more than 1,300 coronavirus cases. The majority of them are on Oahu and Maui.

>> On Oahu, officials are investigating 18 clusters with 480 cases, including two at correctional facilities with 276 cases, five at restaurants with 74 cases, four at food suppliers with 52 cases, four at educational settings with 35 cases, and a social gathering that resulted in 13 cases, among others.

>> On Maui County, officials are investigating 44 clusters with 461 cases, including one at the correctional facility with 122 cases, 10 at educational settings with 92 cases, 12 in the travel, lodging and tourism category with 90 cases, eight at restaurants with 31 cases, two at food suppliers with 24 cases, and seven in the “other” category with 73 cases, among several others in construction and occupational settings.

>> On Hawaii County, officials are only investigating one cluster at the correctional facility with 296 cases. The same cluster may be included in multiple reports from week to week if a new case has been identified within 14 days of the final report.

>> On Kauai County, officials are investigating a cluster at the correctional facility with 87 cases, a restaurant cluster with 17 cases, two social gathering clusters with 18 cases, a construction and industrial cluster with eight cases, an other occupational cluster with four cases, and a place of worship cluster with three cases.