The Houston rodeo with typical daily attendance between 50,000 and 75,000 (1) was cancelled 14 days ago, March 11 (2). South by Southwest was cancelled March 6, before it began, giving individual Texans a wake up call (3). Travel from Europe was stopped Friday the 13th (4) and until that time Houston’s international airport was freely receiving visitors from Italy. These three actions definitely did produce some voluntary, spontaneous social distancing, though likely not enough by itself to reduce the spread of Sars-COV2.
Texas went from 1,908 cumulative Sars-COV2 tests 7 days ago to 13,494 as of today, the vast majority of them still negative even among symptomatic individuals. (5, 6) Update: The daily case count on the Covid Tracking website has an error. The case total reported by the state on March 24 was over 700 and went to 974 on March 25. It appears that they may have left out one week of case data, as the March 24 increase was big. It was actually the biggest single day increase but it was nowhere near a tripling of cases overnight.
The incubation rate of Sars-COV2 is 1 to 14 days, with a median of 5 days. The first major milestone, the 14 day mark from the closure of the rodeo, passed with no major change (9).
Greg Abbott ordered all bars, restaurants, and schools closed 6 days ago. (7) Harris County did so three days before that. (8) We can expect another 5 to 8 days to see how much effect that will have had, because the incubation period can be up to 14 days (9).
The estimated R0, the number of people infected by each infected person, is between 2 and 2.5, likely around 2.2 according to trained epidemiologists conducting peer reviewed studies (10). At an R0 below 1, the virus begins to burn istelf out with slowly declining case rates. The R0 doesn’t have to be cut to nothing, it has to be cut below 1. (12) It has to be cut by 50 to 60% for this to happen. (57% would reduce the R0 from 2.2 to .95.)
The local population became obsessed with both hand sanitizer and hand washing since March 11. (This is the one point in this article for which I do not provide a source other than my own observation. I bought a hand sanitizer on March 10 and could not find any in Houston or online by March 12.) The people who couldn’t find hand sanitizer have been obsessively hand washing, whcih is even more effective. Major gatherings have been cancelled. Minor gatherings have been discouraged. Bars are closed. Schools, notorious factories of infection, are closed.
Everyone should be aware that, since recovery takes up to six weeks for severe cases according to the World Health Organization (11), the decline which is coming will be slow to start with and the total case count may increase even after the rate of infection declines significantly.
Finally, to date we have not implemented the approach that is actually recommended by epidemiologists for disease more infectious than this one (14) and which worked to contain the spread in South Korea (13) – testing for the disease, tracking contacts of infected people, and isolating the infected. We have taken the step of essentially quarantining millions of healthy people instead. While New York likely does fall under the category of “too late” to take lighter measures, Texas and indeed most of the United States do not.
Bottom line: Don’t max out your credit cards and mortgage your house to stockpile toilet paper, and more importantly – stop demanding that government further erode our rights.
1 – https://www.rodeohouston.com/About-Us/Who-We-Are/Attendance
2 – https://www.chron.com/news/houston-texas/houston/article/houston-rodeo-shut-down-coronavirus-concerns-15123010.php
3 – https://www.citylab.com/equity/2020/03/sxsw-cancellation-coronavirus-austin-music-film-festival/607669/
4 – https://www.politico.eu/article/coronavirus-donald-trump-europe-travel-ban-explained/
5 – https://covidtracking.com/data/state/texas/
6 – https://www.dshs.state.tx.us/news/updates.shtm#coronavirus
8 – https://www.houstonchronicle.com/news/houston-texas/houston/article/New-York-LA-Chicago-order-bars-restaurants-to-15134459.php
10 – https://www.ncbi.nlm.nih.gov/books/NBK554776/
11 – https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19—24-february-2020
12 – https://www.healthline.com/health/r-nought-reproduction-number#rsubsubvalues
13 – https://www.nytimes.com/2020/03/23/world/asia/coronavirus-south-korea-flatten-curve.html
14 – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6207419/