Terrifying! A second case of "community transmission" of the Wuhan coronavirus has now been confirmed in Santa Clara County, marking the first two U.S. instances — both in the Bay Area — of an infection with no discernible connection to a traveler returned from China.

The Bay Area is poised to become a new nexus of the covid-19 pandemic, as two cases of community transmission have been discovered here in just two days — suggesting that the virus is already circulating in at least two communities, in and around Vacaville and Santa Clara County.

The first such case just appeared on Wednesday, in Solano County, and the patient there is a woman who was hospitalized with respiratory problems who was not properly tested for the virus for at least four days.

As the Chronicle reports via county health officials, the Santa Clara County patient is an older woman with chronic health conditions who was hospitalized with a respiratory illness. She had not been traveling recently and had no known contact with anyone who had been traveling or had exposure to the virus.

The Washington Post reported earlier today that the woman is 65 years old. And unlike in the Solano County case, where dozens of infected or potentially exposed people have landed after being evacuated from China and the Diamond Princess cruise ship, there have only been two previously confirmed cases in Santa Clara County.

Jennifer Nuzzo, senior scholar at the Johns Hopkins Center for Health Security, tells the Post, "I think there’s a strong possibility that there’s local transmission going on in California. In other words, the virus is spreading within California, and I think there’s a possibility other states are in the same boat — they just haven’t recognized that yet."

Brace yourselves for more panic as the next week unfolds.

Related: Newsom: 8,400 Californians Being Monitored for Coronavirus