As the city of San Francisco approaches its 5,000th confirmed case of COVID-19, likely sometime this week, Mayor London Breed and Health Director Dr. Grant Colfax issued some grim predictions for the second half of the year, if infections don't slow down.

San Francisco is potentially looking at "a situation that reflects the challenges New York had" if the city's infection reproduction rate (Rt) doesn't dip back below 1.0 where it was back in May and early June, Colfax said in a Monday presentation. Looking at data up to July 4, the city's Rt metric is at 1.25.

"This is the slide that keeps me up at night," Dr. Colfax said as he showed graphs of hospitalization and infection rates projected through the end of the year. A median projection of hospitalizations, given the current rate of new infections, would put SF in a scenario with 830 COVID patients hospitalized on a given day in November.

"Let's think about that for a minute," he said, per ABC 7. "In April, we peaked at 94 hospitalizations."

Graph via SF Dept. of Public Health via UC Berkeley

A worst-case scenario would see a peak of 6,000 severely ill patients hospitalized with the coronavirus by early to mid-October.

While an Rt of 1.25 does not seem high, it represents the possibility of exponential growth. An Rt below 1, which is currently only being seen in Washington, D.C., Arkansas, and several New England states, means that infections will fall and eventually drop to zero — though maintaining that will likely require a return to more draconian sheltering measures.

Graph via SF Dept. of Public Health via UC Berkeley

The death toll in San Francisco remains relatively low compared to many U.S. cities, with only 50 deaths to date. However Colfax delivered the sobering news that the worst-case scenario projection puts us up around 3,000 deaths in the next six months.

"These times are hard but having a mass pandemic in our city is even worse," Colfax said.

So much for bars ever reopening...

Related: COVID Hospitalization Rates Consistently Rising Across The Bay Area