After one day with no new cases, the San Francisco Department of Public Health says that it has four more confirmed cases in the city — and it will now be updating the tally daily at 10 a.m. instead of noon.
News went up on the department website Thursday morning that the total number of confirmed cases in the city has risen to 18, up from 14 the last two days. As KRON4 reports via health officials, two of the new cases are hospitalized in isolation, and two are currently isolated at home. One of the four had a known contact with an existing confirmed case, while the other three did not — meaning that they were the result of community spread.
We have known that community spread is occurring on some level here since the first confirmed cases were reported — neither of the first two SF cases had known contacts with anyone who had traveled to an affected country.
The only place in the U.S. so far that has done a specific tracing investigation with regard to community spread of the virus is New York, where one attorney who lives in New Rochelle just outside of Manhattan, and works near Grand Central Station, is seen as the original source for 50 infections, including those of his family and a friend's family, and several members of a synagogue he attends. Also infected were two caterers who worked at a bar mitzvah attended by the attorney before he became ill. It was this outbreak that has led to the unprecedented lockdown of a perimeter around New Rochelle this week — between March 2, when the attorney was hospitalized, and March 10, there were 108 cases in that town alone, which Governor Andrew Cuomo called a "true geographic cluster."
The New Rochelle attorney's case is becoming an early case study — like the Patient Zero case in Washington State — in how rapidly and widely the coronavirus can spread from just a single carrier, and how wildly contagious it appears to be.