It is possible to perform indoors if taking appropriate safety precautions.  

"I have been in restaurants that are doing things perfectly right: great air filtration, air exchange, good distance between people. I truly believe that there are some performing arts venues that can be operated safely if they have taken the approach of looking after the indoor air environment and then creating enough physical distance between people."

Wearing masks, even on singers, greatly reduces the risk of transmission.

"Good-fitting masks — and I've seen some great opera masks being worn that sort of have billows underneath that will capture the majority of material that is coming out — can substantially lower risk. There's risk in two directions: There's the risk of releasing it into the environment, but then also inhaling it in. So when we're wearing masks and wearing them in indoor environments, it's important to have [a mask] on both people. [If I] reduce the risk 90 percent on the way out and 90 percent on the way in, my risk is now one percent of what it was before if none of us were wearing masks."

Outdoor performances are safer due to unlimited ventilation, but they still require safety measures.

"We know the risk is much, much lower outdoors — about 20 fold lower than being indoors. ... The way I like to think about it is, even outdoors if somebody is smoking a cigarette, there are certain spots that you don't want to stand if you're a non-smoker. And so, it's the same thing with a singer: If you wouldn't want to stand in that position if someone was smoking a cigarette and you're trying not to smell it, you would not want to stand there if you're a singer."

Another factor to consider is performance duration.

"We know that the longer you are singing, the longer that you're involved or exposed, the riskier it becomes. We may need to start thinking about doing pauses. That's what we were originally thinking with Boston Lyric Opera: 10 or 15 minutes of performance and then a break to ventilate and air out the space, and then start again. So when you can't get the air environment perfect, you can alter it with duration."

Based on the rate of vaccination, theaters could begin to open as early as June 2021.

"We're actually vaccinating at the same rate as we're infecting right now, but that means that we're moving through the population fairly fast. I really do see that there are going to be significant differences in what we are able to do safely starting in about June of this year. ... We may still have some protocols by June in high-risk environments. But I think we are starting to normalize and find a way to pursue the things that we have done in the past starting around the end of June this year."