DOH: Maui middle school cases linked to ‘spillover’ clusters

Department of Health officials are investigating a cluster of COVID cases at a Maui middle school that they say is linked to “spillover” outbreaks in other locations.

“All the cases in the school cluster to date can be linked to source cases in their households that belong to two other clusters, one in a large faithbased setting and another among hotel employees,” DOH said in its weekly cluster report Thursday. “Thus, the numbers represent cases who are being counted twice in separate clusters.”

Tracking the sources of some COVID-19 cases can be fairly straightforward — for example, a person who stays home and is visited by only one person who recently tested positive. Other scenarios can prove more complicated, such as a husband and wife who test positive and turn out to have multiple co-workers in separate settings who also caught the virus.

“These complicated cases require the investigator to understand the timing of when people became sick, what exposures they may have had, and other factors,” the department explained. “Sometimes it is discovered that transmission occurred somewhere other than where it was first assumed to have occurred. For instance, two children who go to the same school test positive, but investigation later determines that transmission most likely occurred at a birthday party. In this scenario, one cluster ‘spills over’ into another.”

The department said this is what happened with the middle school cluster, and that “investigations are ongoing to evaluate whether any further transmission could have occurred in the school setting.” The cluster associated with the large faith-based setting is also linked to a cluster in a smaller faith-based setting, another example of “spillover.”

Maui County currently has the most active clusters in the state, with the largest outbreak of 93 cases at the Maui Community Correctional Center and another cluster of 40 cases connected to cleaning services. The cluster connected to a place of worship has reached 25 cases; while two clusters of 16 cases are linked to bars and nightclubs; three clusters of 15 cases are associated with the travel, lodging and tourism industry; two clusters of 12 cases are attributed to other occupational settings; and one cluster of eight cases is tied to food suppliers.

Because the department does not identify specific locations, it did not name the Maui middle school but did report one cluster of eight cases in an educational setting.

The department also said that clusters in hotel and accommodation settings are of concern with the increasing numbers of visitors to the state and more hospitality industry employees returning to work.

All 15 cases in the three active clusters connected with hotels have been among employees, and all are residents, including one with recent interisland travel history, the DOH said. None of the cases were visitors, and no close contact with visitors was reported.

“In at least one instance, noncompliance to masking requirements was observed in the environment,” the DOH said. “As with other industries, social interactions among coworkers at or outside of work are the most common link found between cases in hospitality industry settings.”

Honolulu County, despite seeing more visitors than other islands, had no clusters connected to the travel industry. The county had two clusters of 22 cases connected to educational settings, two clusters of 19 cases linked to restaurants and one cluster of eight cases associated with the construction and industrial category.

Hawaii and Kauai counties had no active clusters, according to the report.