Washington state wedding may have caused deadly outbreak in 2 long-term care facilities: Officials

A Washington state wedding that was called a "super-spreader" event may have caused deadly COVID-19 outbreaks in two long-term care facilities, officials said Friday.

Over 300 people attended the Nov. 7 wedding in rural Ritzville, in Adams County, officials said. Ten days later, nearly 40 attendees from neighboring Grant County had tested positive for COVID-19, the local health department said at the time.

Staff at two long-term care facilities in the county who attended the wedding subsequently tested positive for COVID-19, according to the Grant County Health District. They worked while contagious but before they knew they were sick, officials said on Friday, though it is unclear how many cases can be traced to the attendees.

"They care for all residents so it will not be known which cases are tied to the staff," Grant County Health District administrator Theresa Adkinson told ABC News in an email.

The department plans to do a "deeper data analysis" of the outbreaks once its COVID-19 surge is better controlled, Adkinson said.

There have been 54 total COVID-19 deaths in the county -- double what was reported on Nov. 5. Out of those, 29 have been identified by the health district as being associated with long-term care facilities, such as nursing homes and adult homes. As of Friday, there are also 13 suspected COVID-19 deaths in the county, including nine associated with long-term care facilities.

On Thursday, as the county reported its current death toll, the health district urged residents to stay home.

"Our most vulnerable community members -- elderly, immunocompromised, and those with chronic conditions -- are especially at risk of complications due to a COVID-19 infection and we must continue to take measures to protect them from this disease," the health district said in a statement. "The best way to do that is by staying home as much as possible. Your choice to gather with those outside your household could lead to additional cases of COVID-19 and even death. Please protect those you love, by staying home."

Long-term care facilities are especially vulnerable to COVID-19 outbreaks, given their congregate setting and elderly population. As of Nov. 30, long-term care facilities were associated with 53% of total COVID-19 deaths in Washington, but only 6% of total cases, the state health department reported.

Large indoor gatherings also pose a high risk for COVID-19 transmission and have the potential to be "super-spreading events," the Centers for Disease Control and Prevention said in a November report. "Such events are associated with explosive growth, followed by sustained transmission."

An August wedding in rural Maine was linked to 177 COVID-19 cases and seven deaths, including six in a long-term care facility, the CDC said.

The Ritzville wedding was also a "super-spreader" event, Karen Potts, Adams County Health Department’s community health director, told reporters last month. "You have a lot of people indoors, close together."

At the time of the Ritzville event, wedding ceremonies in the state were limited to 30 people.

Under the most-recent state order, issued as Washington experiences a "third wave" of the virus, weddings are prohibited indoors and social gatherings with guests from outside the household are prohibited unless the guests quarantine.

What to know about the coronavirus:

• How it started and how to protect yourself: Coronavirus explained
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