Philly Leader

98.4 percent of Philadelphia County COVID-19 patients have survived as of Jan. 25, according to the COVID-19 Data Repository by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University.

The CSSE confirmed there were 291,747 COVID-19 cases in Philadelphia County by Jan. 25.

There were 4,557 fatalities, equalling 1.6 percent of Philadelphia County's COVID-19 patients.

More than 50 percent of US citizens are considered fully vaccinated against COVID-19, nearing the target for "herd immunity." Herd immunity happens when enough of the population has become immune to the virus from previous infection that it effectively protects those who are not immune.

"The number of people who are immune to the coronavirus is increasing every day," professors David Dowdy and Gypsyamber D'Souza said in an interview.