"It is clear we will be living with this virus for a long time. But the situation isn't forever. There is some hope," health commissioner Dr. Thomas Farley said during a Thursday press briefing.
As Pennsylvania reported its highest one-day total of confirmed coronavirus cases since May, Farley said overall progress of developing a vaccine for the coronavirus has been extremely rapid.
He said dozens of research groups have developed vaccines that have produced antibodies which have been administered to animals. The antibodies appear to protect those animals from the infection.
Farley said it looks like it's easy to train the immune system to recognize and kill the coronavirus, much easier than other viruses.
"To put it in plain language," Farley said, "COVID-19 is nasty, but it looks like it's not very smart."
Farley cited The New York Times' Coronavirus Vaccine Tracker. It currently shows 145 vaccines in development, 20 of which are in human trials.
Three vaccines are particularly promising, Farley said, that are being supported by the U.S. government's Operation Warp Speed program.
The farthest along, developed by AstraZeneca and the University of Oxford, is now testing their vaccine on more than 10,000 people across the United Kingdom, Brazil, and South Africa.
"They try to find out how effective the vaccine is at preventing infection in people or preventing severe disease in people, and they are testing the safety of the vaccine," Farley said.
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Once a vaccine is proven effective and safe, Farley said it will take some time for the company to produce the hundreds of millions of doses needed to be distributed.
"I'm optimistic that we will have at least one, and maybe more than one, vaccine that we are deploying here in Philadelphia sometime in 2021," Farley said.
The health commissioner said it's too early to determine if it would be early in the year or later in 2021.
"After we do that, and we feel we are protected from this virus, we can take off our masks, and we can get together again," Farley said.
On Thursday, Philadelphia announced 143 additional positive cases of coronavirus, bringing the citywide total to 26,400. There were five more deaths, bringing the total to 1,1614.
Farley said a third of the new cases in the past week have been people under the age of 30, and some are in people who have traveled to the shore.
Health officials monitoring mask usage
The Philadelphia Department of Health has been monitoring mask usage in places like subway stations and stores across the city. Farley says we need improvement.
"It is clear we'll be living with virus for a long time," said Farley.
Cases in the city this week increased from an average of 110 per day to 143 in the last 24 hours. One third of the new coronavirus cases in Philadelphia are in people younger than 30.
"There's a lot of young people that choose not to wear the mask when they go out to certain events and stuff," said Jabrea Kennedy of Southwest Philadelphia.
"To me without this, shows a disrespect for all of you. It's all about respect," said Pam Zenzola of South Philadelphia.
She's seen a shift in behavior when it comes to mask wearing.
"Everybody was getting into it. Then there was a lack, everyone was slacking off, if you will. And then in the last few days definitely more. Not enough! Still need everybody," said Zenzola.
Now, officials are monitoring compliance.
"We are looking at people who are at indoor septa stations and inside stores at scattered places throughout the city," said Farley.
Throughout the survey, 55% of commuters at SEPTA stations wore a mask and 78% of customers in store cameras did.
Farley wants to see those numbers rise to at least 80%.