SAN FRANCISCO, Calif. (KRON) – “We talk about what the new normal will look like, normal it will not be until we have herd immunity and a vaccine,” Governor Gavin Newsom said.
The term herd immunity came up again Tuesday as the governor discussed modifying the stay at home order put in place to slow the spread of the coronavirus.
“Herd immunity refers to a phenomenon when there is enough immunity in a population where a microorganism cannot be transmitted efficiently and dies out, for measles that is 96% of the population” Dr. George Rutherford said.
UCSF infectious disease specialist Dr. George Rutherford says there are two primary ways to achieve herd immunity.
“In the old days everyone got infected, measles, rubella and chicken pox in schools,” Rutherford said.
Rutherford says that’s not how herd immunity will be achieved with COVID-19 because as high as the number of infections seems, it’s not even approaching more than 90% of the population.
“In northern Italy, they have calculated to less than 4%, so here where we are less scathed it will be quite low,” Rutherford said.
Low meaning about 1%. That means more likely way to create herd immunity is the way it’s done now for measles mumps and whooping cough, through a vaccine.
The idea being the more people who have got a vaccine allowing them to fight off the virus and prevent infection, the fewer people who will be able to spread it to one another.
As we keep hearing that vaccine is still at least a year to a year and a half off, another reason for continued social distancing.