Philly sets re-masking precedent, but Chicago's not following suit

Philadelphia officials announced the return of an indoor mask mandate starting April 18 due to rising COVID-19 cases and hospitalizations.

Why it matters: Chicago's case rates are higher than Philly's, but local officials don't seem any closer to following suit.

By the numbers: Philly is reporting about 225 cases a day, while Chicago's daily average was 414 yesterday.

• For comparison's sake, Philly has a million fewer residents than Chicago and has also seen a more than 50% jump in hospitalizations over the last 10 days.

What they're saying: "While Chicago and much of the country are experiencing an increase in new COVID-19 cases, hospitalizations and deaths are as low as we've seen them since the start of the pandemic," city officials tell Axios in a statement.

Yes, but: Local cases are likely much higher than official figures suggest because the city doesn't count positive home test results.

• Better infection indicators, like last week's CDC wastewater report, showed 1,000% to 1,000,000% increases in COVID prevalence for some Cook County areas.
• Those wastewater figures do appear more stable this week, though IDPH officials say that wastewater data interpretation is still "a work in progress."

The latest: IDPH announced yesterday it's moving to metrics that more closely follow the CDC model — ditching positivity rates while leaning almost entirely on case rates per 100k and hospitalizations.

The bottom line: Those CDC COVID metrics still classify Chicago's community COVID levels as "low," with no need to reinstate mandatory masking.

• But they also say the same thing about Philly.