TRENTON, NJ – New Jersey restaurants are staying closed for indoor dining and Governor Murphy said a study of a restaurant in China done back in January of 2020 is the reason why. In that study, it found that the ventilation and airflow of the restaurant between an exhaust fan and a wall-mounted air conditioning unit pushed the COVID-19 virus droplets from table to table, infecting 10 people.
That study found no COVID-19 nucleotides within the airconditioning unit itself and admitted it did not test its theories described in its findings.
“While we’re at it, let’s also illustrate one of the reasons why we’ve been so concerned about reopening restaurants for indoor dining. And by the way, I hope we’ll get there, and I hope we get there sooner than later, but there’s a video clip we want to show you that illustrates a case study of coronavirus spread in January that occurred in a restaurant in southern China, in this case was published in the journal Emerging Infectious Diseases,” Murphy said. “In this instance, one infected and contagious diner at this middle table was able to spread coronavirus to nine other diners at the tables to their left and right, including some seated as far as 14 feet away.”
Each table was seated in overlapping intervals lasting up to 53 minutes the report said.
“From our examination of the potential routes of transmission, we concluded that the most likely cause of this outbreak was droplet transmission. Although the index patient (patient A1) was asymptomatic during the lunch, presymptomatic transmission has been reported (1). Given the incubation periods for family B (Appendix Figure), the most likely scenario is that all 3 family B members were directly infected by patient A1. However, we cannot not exclude the possibility that patients B2 and B3 were infected by patient B1, the first family B member to become ill. For family C, a possible scenario is that both patients C1 and C2 were infected by patient A1; another scenario is that the patient C1 acquired the infection while caring for patient C2, beginning on January 27,” the report said.
“The common thread was that all of these patrons were seated in a straight line from an air conditioner. I think any of us can name any number of restaurants that we go to which have a seating arrangement and air conditioning situation not unlike the one in this restaurant halfway around the globe. Airflow is a constant concern,” Murphy said. “This is why we have been much more forthright in reopening outdoor activities, including outdoor dining, while limiting indoor ones and requiring masks to be worn at all times while indoors. Allowing diners to sit maskless for an extended period of time in a restaurant where the air conditioning unit can silently spread coronavirus is a risk we cannot take.”
“Our study has limitations. We did not conduct an experimental study simulating the airborne transmission route. We also did not perform serologic studies of swab sample–negative asymptomatic family members and other diners to estimate risk for infection,” the writers of the report stated. “We conclude that in this outbreak, droplet transmission was prompted by air-conditioned ventilation. The key factor for infection was the direction of the airflow.”
The American Society of Heating, Refrigerating and Air Conditioner Engineers have given restaurants guidance on how to reduce the risk of airborne exposure to COVID-19.
“Transmission of SARS-CoV-2 through the air is sufficiently likely that airborne exposure to the virus should be controlled. Changes to building operations, including the operation of heating, ventilating, and air-conditioning systems, can reduce airborne exposures,” ASHRAE said. “Ventilation and filtration provided by heating, ventilating, and air-conditioning systems can reduce the airborne concentration of SARS-CoV-2 and thus the risk of transmission through the air.”
Photo by Carlos Lindner on Unsplash