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COVID-19: Good news


March 22 2020

Some good news in San Diego: We are making progress controlling the spread of the virus, and the full lockdown now in effect should control its spread even more.

==COVID-19’s growth rate==

COVID-19’s growth in San Diego

The amount of growth we are currently seeing (which should go down) would saturate San Diego’s population in about eight weeks. Previous growth, before the quarantine was in effect, would had saturated our population in five weeks.

The thing to keep in mind is that we can stop saturation with less economic impact once we ramp up testing: We test large numbers of people and only quarantine those who test positive. This way, we can hang out with our friends and open up schools again, without the virus spreading unchecked. But we need wide scale testing to pull it off.

If we can get the growth factor to be small enough, the virus will burn out; I don’t think that’s achievable without testing, but, then again, I’m a computer software developer, not an epidemiologist.


As of the afternoon of March 22, San Diego now has 205 cases, which is a 29% increase over the previous day. This is a higher increase than the one we had the previous day (21%), so is hopefully just a blip and we will see the increase go down again.

March 23, 2020 update: San Diego now has 230 cases, which is only a 12% increase from yesterday. Taking in to account yesterday’s blip, we are seeing the same 21% increase we saw two days ago; saturation (everyone in San Diego being infected) remains about seven or eight weeks away. If this 12% increase can be sustained, saturation will take 12 weeks, probably longer.

March 24, 2020 update: San Diego has 242 cases, only a 5% growth from yesterday. The quarantine is working! It would take over six months to saturate at this point; we may have effective medicines and possibly even a vaccine before then.

Final update: San Diego has 1696 cases and a doubling time of over 11 days on April 11, 2020.

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