How An Inflatable Costume May Be to Blame for a Deadly COVID Outbreak in a Hospital

A coronavirus outbreak at the Kaiser Permanente San Jose Emergency Department in California in late 2020 infected at least 43 other staff members and resulted in one death, hospital officials said in a statement released on January 3. The outbreak may have been spread by an inflatable Christmas tree costume with a fan inside it that was worn by one employee, according to The Washington Post.

"Hospital officials now say the 'air-powered' Christmas costume is likely to blame for the 44 positive tests, all recorded between December 27 and January 1," wrote the Washington Post in an article on January 4. "Experts said the fan inside the costume could have blown coronavirus-laden droplets throughout the department."

KNTV-TV, the San Jose NBC station that broke the news, said the employee who died was a woman who worked as a registration clerk in the emergency department. However, the hospital didn't confirm whether the employee, who died after working the Christmas shift, was one of the 43 who tested positive for COVID-19 between December 27 and January 1. "Out of respect for patient privacy, we have no additional information to provide," officials said a statement to the San Francisco Chronicle.

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Accidental Covid Spread

Kaiser Vice President Irene Chavez said that an investigation was underway to try to establish whether the sudden spread of COVID-19 was due to the employee who wore an inflatable holiday-themed costume in the emergency department. According to officials, one of the infected employees did "appear briefly in the emergency department on December 25 wearing an air-powered costume," according to the statement.

The hospital statement added, "Any exposure, if it occurred, would have been completely innocent, and quite accidental, as the individual had no COVID symptoms and only sought to lift the spirits of those around them during what is a very stressful time." KNTV-TV reported that the inflatable Christmas tree costume is typically battery-powered and uses a fan to stay inflated.

How could an inflatable costume increase the spread of infection? It's possible that if the costume wasn't completely sealed, its mechanism could push air and respiratory droplets in various different directions, infectious disease expert Amesh A. Adalja, MD, senior scholar at the Johns Hopkins Center for Health Security in Maryland, tells Health.

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Ways Covid Can Spread

Throughout the pandemic, there have been other examples of strong drafts of air increasing the spread of the virus. In a Centers for Disease Control Prevention (CDC) report published in July 2020, it was revealed that in the southern Chinese city of Guangzhou, a pre-symptomatic person who was eating lunch at a restaurant with family infected two other families sitting at neighboring tables about three feet away. Scientists suggested that airflow powered by the restaurant's air-conditioning system dispersed infectious droplets from the pre-symptomatic person.

The coronavirus can be spread via all types of surfaces in an indoor setting, even without something inflatable moving around. But Dr. Adalja points out that an inflatable costume is unlikely to be cleaned in the same manner as other surfaces in the emergency department. He adds that even if the costume covered the wearer's face, it may not have provided full respiratory protection.

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However, it's possible that the spread of COVID-19 in the San Jose ER had nothing to do with the inflatable costume. "It's important to do a full epidemiological investigation to rule out other sources," Dr. Adalja says. "In an emergency department, the coronavirus can spread between infected patients and employees."

"If anything, this should serve as a very real reminder that the virus is widespread, and often without symptoms, and we must all be vigilant," said Chavez, who added that inflatable costumes will "obviously" no longer be allowed in the hospital, and steps were being taken to reinforce safety precautions among staff. These steps included no gatherings in break rooms, no sharing of food and beverages, and the wearing of face coverings at all times, she added.

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.