Last week, the governor of Texas lifted all COVID restrictions, to be effective March 10, in the middle of Spring Break for most of Texas. He acknowledged COVID hasn’t disappeared, but is confident we have enough vaccine to get ahead of this pandemic.

The current 7-day average is between 4000–5000 new cases per day across the state.

Eric Gay/AP Riverwalk, San Antonio.

So do we have enough people vaccinated?

There are 26.2 million people over the age of 16 (the youngest age for the Pfizer vaccine). As of March 5, 2021, 8.56% of people over 16 have been fully vaccinated and 15.5% have received at…


But maybe not in April 2021

Edit: definitely not in April and maybe not in June, definitely not indoor events in June.

San Antonio Express-News Photo: Kin Man Hui / Staff file photo.

For those not in San Antonio, Texas, Fiesta is an annual, officially 10 day but unofficially nearly month long celebration of the life and culture of San Antonio. Fiesta also serves as a major source of fundraising for many non-profits as well as the city. It has an economic impact of $340 million each year for San Antonio. And not just that, it’s a significant part of our culture and community. …


As COVID continues to rear its ugly head, in San Antonio we’ve seen cases inching up for the last few weeks. Yes we’re testing more. An increasing positivity rate means we’re finding cases, which is the only way to stop it spreading undetected.

In March, I wrote about what we’d likely see in San Antonio. And we did. In July, Black and Hispanic/Latinos disproportionately affected. Also in March, I wrote about T3: testing, tracing, tracking (isolation/quarantine).

In April, the mayor of San Antonio had the wisdom to pull together experts from across the city to develop a “Transition Plan.” The…


Confession. One of my favorite parts of applied epidemiology is trying to find the source of an outbreak. It is, after all, what the Father of Epi, John Snow, did to stop the cholera outbreak.

Identifying the *source* of an outbreak of a respiratory disease is more difficult. On an individual case level, it’s rare that we can, unless we do molecular epidemiology. We can, however, identify clusters.

There are two parts to Disease Investigation:

Prospective Contact Tracing

This is when we talk to a case, find out with whom they’ve been in contact (for COVID, we ask for 48…


Quickie summary of flu in Texas for those who asked.

The 2008–2009 flu season was relatively mild, with a small peak in late January/early February (blue line). But in April of 2009, the first cases of H1N1, later to be a pandemic, were identified in Guadalupe County. Cases dropped over the summer, then spiked up again in late August/early September (orange line). The remainder of the season stayed mild. The 2010–2011 season saw cases start to peak in mid-January into February

April is usually the end of flu season. But in April of 2009, 2 individuals in Guadalupe County were…


Six plus months into this pandemic, my spouse has overheard many calls. So when recently he listened to me answer the same question — if different ways — 10 times, he asked “How can you stand answering over and over again?”

I hadn’t even noticed.

I once had a professor who, after I’d asked to explain something for the umpteenth time, then apologized for not getting it sooner, say that my not getting it meant he didn’t understand it well enough to explain it clearly.

And that’s how I view those questions — ask me 10 times, I’ll try 10…


In the Spring and well into the summer, reliance upon the gold standard RT-PCR tests meant a delay in results across the country. At times, results might take up to two weeks, long past the time the individual was contagious. There has been much talk of rapid COVID-19 tests to identify positive individuals more quickly. And we have them now, we call them “Antigen tests.”

There are many different types, but first let’s explain the scientific jargon.

RT-PCR is “real time reverse transcriptase polymerase chain reaction.” This is a molecular test that picks up viral RNA in the person’s’ nostrils…


A couple of weeks ago, I wrote about the Spurs and victory being snatched from us at the last moments.

Here’s an update: we’re holding steady, but still above the threshold recommended by Dr. Tom Frieden, former CDC director (back when we could trust the CDC) and lead of Resolve to Save Lives. His team suggests less than 40 NEW cases per 1 Million people per day on average is needed to shift from Level 4 High Alert to Level 3 Moderate. Here is San Antonio compared to the (simplified) global alert system:

San Antonio Data from COSA. See note below re staffed bed.

The black line is the 40 per…


How many of us San Antonio Spurs fans know the heartbreak of being so close to the victory, only to have it snatched from our grasp at the final buzzer?

San Antonio’s COVID-19 situation feels a bit like a 3rd Quarter rain of threes, pulling out ahead of the Lakers, the Heat, the Mavs.

There has been much excitement locally as Bexar County’s COVID-19 cases continue to decrease. This is great news. Hospitals have more capacity, ICUs are no longer at their limits, everyone can breathe a bit.

We can, and should, celebrate this stage. …


A good friend of mine is a finance guy. One of the best pieces of advice he gave me when I asked about long term investment planning (with my very meager public health income) was “Don’t look at the daily rates. Look at trends over time.” Daily rates go up and down, we need to see long term trends.

The same is true for an outbreak of a respiratory disease with a 14 day incubation period. And especially true for a pandemic when lab results are taking 10–14 days to report.

It’s easy to be hopeful about the recent decline…

Cherise Rohr-Allegrini, PhD, MPH

Dr. Rohr-Allegrini is an epidemiologist and tropical disease scientist currently working to prevent diseases through immunizations.

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