Two outdoor music festivals raise concerns as more than 150 attendees test positive for COVID-19

• Health officials have traced a total of 158 coronavirus cases to two July music festivals.
• Even at outdoor venues, attendees bunching closely together results in high aerosol exposure.
• NYC will enforce proof of vaccination at concerts starting September 13.

Health officials are investigating recent COVID-19 outbreaks related to two outdoor music festivals as the delta variant continues to spread across the US.

Officials traced 96 cases to the Faster Horses Festival held in Brooklyn, Michigan, from July 16-18, and 62 cases to the Pendleton Whisky Music Fest held in Pendleton, Oregon, on July 10, neither of which required attendees to be vaccinated, Rolling Stone reported.

Umatilla County, Oregon, Public Health Director Joe Fiumara told Rolling Stone that contact tracing confirmed that much of the transmission took place in an area where fans were in close proximity with each other.

The CDC updated its guidance on July 27, recommending fully vaccinated people wear masks in public indoor settings in areas of substantial or high transmission.

"If you're outside and you're packed in with someone, it's getting closer to being like an indoor environment, where you have really high aerosol exposure from the person that's a foot from you, or even inches from you," aerosol scientist Alex Huffman told Rolling Stone.

Other music festivals are opting for stricter approaches. Organizers for New Jersey's Sea Hear Now festival, slated to bring Pearl Jam, The Smashing Pumpkins, Patti Smith, and Billy Idol to Asbury Park on September 18 and 19, will require attendees to either be fully vaccinated against COVID-19 or produce a negative test result, according to NJ.com.

Starting September 13, attendees of concerts in New York City will be required to provide proof of vaccination using the city's new app, the state's Excelsior app, or a paper card, The New York Times reported.