Sam Trenholme's webpage
Support this website

COVID-19 growth


June 30 2020

COVID-19 is undergoing exponential growth again. 362 words

==COVID-19’s growth is going up==

COVID-19’s doubling time in San Diego. Lower numbers mean faster growth.

The number of COVID-19 cases in San Diego is surging. More worrying, the growth rate is surging, decreasing the doubling time.

At the current growth rate, we will have COVID-19 herd immunity (i.e. pretty much everyone will be exposed to COVID-19) by mid-October.

It does not appear to be the George Floyd protests which have caused growth to go up again; it looks like our re-opening of the economy is causing growth to go up.

Bars are already starting to close in other parts of California. The county with the most COVID-19 growth right now is Marin county, just north of San Francisco; my data shows that they are projected to have herd immunity in a month.

I am doing my best to stay at home, only leaving for a socially distanced walk, to buy groceries, or to take my daughter to and from school. I wear a mask if in an indoor public space; I maintain a distance of six feet from other people when going on my daily walks.

I have decided that it’s worth the increased possible exposure to the COVID-19 virus for my daughter to be back in school and able to socialize with her peers. They are taking a lot of measures to reduce spread at the school.

The New York Times recently published an opinion piece on why it is important for kids to go back to school.1

==MaraDNS update==

I am in the process of getting MaraDNS 3.5.0006 out the door. I have updated the Deadwood parser to no longer always be Python 2 compatible; leading whitespace is now allowed in Deadwood configuration files. The reason for this change is because Python 2 is no longer supported by the Python Software Foundation. Since Deadwood’s configuration files are not always Python 3 compatible, I no longer see a need for its configuration file be a full subset of Python 2 syntax.

I should have the 3.5.0006 release out later this week.


The COVID-19 data comes from The New York Times, over at I process the data to get doubling time figures, both actual and predicted; that code can be seen at While facts can not be copyrighted, The New York Times claims copyright on their COVID-19 data.

For a discussion on why it’s important for kids to be in school, see “Remote School Is a Nightmare. Few in Power Care.” by Michelle Goldberg, published by The New York Times.

Did you know that all of my blog entries are available in a free to download eBook at