Watching COVID-19: The OC

Orange County decided to open up their beaches on April 25th, so, it’s a good time to take a look at the Orange County COVID-19 website, and start monitoring their stats.

If many people were infected with SARS-CoV-2 from going to the beach, it could show up in the new cases they report every day.

The population of Orange County, California is 3.17 million people. The beach cities are Laguna Beach, Dana Point, San Clemente, Seal Beach, Huntington Beach, Newport Beach.

On April 25, they had: 1969 cases total, 38 deaths total, 23285 tests.

Testing capacity has generally increased, so while the raw number of positives has increased, the trend should be a smaller proportion of cases are positive. Testing is not random. I think they have rules to ration testing only to people with symptoms. According to their site:

“Because of continued challenges of obtaining testing supplies and Personal Protective
Equipment (PPE) for health care providers conducting tests, testing may be restricted at times to high priority groups, as defined by the California Department of Public Health or Orange County Public Health.”

Testing in Los Angeles is restricted to persons with symptoms, and people who have been in close contact with someone infected.

Requiring symptoms to get tested causes a lag in discovering infection. The virus infects, and then incubates for 2 to 14 days, and after the first signs, people go in to take a test. So, we don’t see changes in the stats for several days after a policy change.

Additionally, we might see not only a surge from the people who went to the beach, but increases in cases from people who live with the people who went to the beach.

Here’s the data. It’ll be updated as time allows, and things progress.

I’m generally against easing up on the stay-at-home rules, but if there’s any place to do it, it’s the beach. I think the risk outdoors can be low, if not too many people crowd into a single place.

I hope this policy change does not increase the cases of COVID-19.

Date Days New TestsNew Cases
4/22-266267 (10%)
4/23-167168 (10%)
4/240126732 (2.5%)
4/2511202124 (10.3%)
4/2622267105 (4.6%)
4/27379454 (6.8%)
4/284139032 (2.3%)
4/2952203108 (4.9%)
4/3061594133 (8.3%)

5/1 – Well, that was short lived. Newsom shut the beaches, and a bunch of nuts went to protest is in Huntington Beach. HB is like the SoCal capital of white rioters and beatings.

As far as the numbers go, maybe there’s a trend starting on 4/30 and 5/1. We won’t know for several days, because there’s no steady trend.

We may need to keep the page going longer, to see if this protest causes a surge.

5/3 – We might not be seeing open beaches.

I did a little averaging of the positive test rates. I threw out the highest and lowest value (10.3 and 2.3), and took the average. The result was 6.92.

The average for the past 5 days was 7.06.

I picked 5 days, because I figure it takes a couple days before symptoms start, and a couple days to get test results.

So, the trend might be an increase in positive cases.

I hesitate to say it is an increase, because I don’t know how this data is collected. I don’t know the rules for testing in OC, nor do I know what a “test” is in their counts.

5/6 – I updated some values, because the dashboard on the OC website changes. Some values have decreased. I hope they aren’t altering the data to look better.

So far, I just don’t see a surge in the proportion of tests that are positive. I’m not sure if we should see a decline in this proportion. (Perhaps looking at another county could be a comparison.)

I do see an increase in the number of case counts. It could simply be that increased testing is catching more cases.

Without information about how many cases could be related back to the beach, I can’t guess if opening the beaches is safe or not.

So far, though, I tend to think the beach is relatively safe. Given that they are testing and could be interviewing people, they should try to find out if the beach became a vector. If it was a vector, they’d know to not open up the beach, or at least open it up differently.





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