Is the SCV Special? COVID-19 and the County Perspective

UPDATE (10:18 pm, 5/14): The sources I obtained numbers from are in the “data dictionary” tab of the embedded spreadsheet. I generally deferred to local sources for Santa Clarita numbers, as they were trying to capture the region, not just the City. A few people have notified me that the County-released numbers spiked by comparison—apparently 15 deaths within just the City of Santa Clarita (population 220,424—does not include non-city portions of the valley), which would almost double the per capita death rate to about 7.7 deaths per 100K. The County hasn’t been perfect in its reporting; it had to fix a Val Verde/Castaic mix-up the other day. I haven’t seen coverage of this yet in the news, so the jump is alarming/puzzling, all the more so because the City reported 7 deaths as the count as of a presentation yesterday morning, and The Signal is still reporting a death count of 8. The bigger story here may be “what counts as a COVID-19 death in Santa Clarita?” Stay tuned.

In brief: The City Council wants to re-open Santa Clarita, justifying their intent by arguing that coronavirus hasn’t struck us nearly as severely as the rest of LA County. It’s true that Santa Clarita’s COVID-19 related death rate is vastly lower than the overall LA County rate. If people were dying here at that rate, there would be over 40 deaths instead of the 8 that have actually occurred. However, infection and death rates are definitely not as low as in the counties that are re-opening quickly, like Modoc. The closest comparisons in terms of death rate per capita are the counties of Contra Costa, Ventura, Solano, and Orange. A few more comparisons: SCV per capita death rate is about 3 per 100K; Alaska about 1 per 100K; California about 8 per 100K; USA about 28 per 100K; New York about 140 per 100K. Obviously, those numbers can go up.

Does the county comparison work?

The City Council wants to begin re-opening Santa Clarita by following State health orders instead of more restrictive LA County orders. This could be accomplished with some kind of order variance or waiver. There would still be some safeguards, but closures and restrictions wouldn’t be as severe as in the rest of LA County.

Various California counties have been allowed to re-open at different paces, so Mayor Cameron Smyth has pitched the idea of re-opening Santa Clarita by comparing the SCV to a county.[1] The SCV’s population exceeds that of many California counties, and it is geographically distinct—should we really have to act like coronavirus has affected us like it did south LA County?

More importantly, has it? And if so, does that means it’s “safe enough” to re-open—and by whose standards and judgment? (An impossible question, I know).

I pulled data from the news and government health websites to put together a hypothetical Santa Clarita “County” comparison. What other counties would we look like if we were our very own, distinct county? Perhaps like the ones that are being allowed to move forward? Below is a Google spreadsheet with three tabs—data, data dictionary to explain the data sources and assumptions, and a chart to make it more digestible.

If the SCV were its own county, it would be doing drastically better than LA County, but not as well as many others in terms of limiting COVID-19 related deaths.

If you want to do a simple statistical test, then yes, the number of COVID-19 deaths for our population size is substantially lower than the number for the rest of LA County ( χ2 = 32.29, p << 0.001). It can be interesting comparing city-to-city too, but that’s for another day.

Many of our neighbors are in the same range of 2-3 coronavirus-related deaths per 100,000 residents—Ventura, Orange, Santa Barbara, and Kern Counties. They’re taking different approaches, so I’m not sure what actionable lessons can be gleaned from the similarity in rates. Maybe it’s just all about geography.

The SCV data shows a high number of confirmed cases per capita despite relatively few deaths. As many have pointed out, simply reporting the number of cases can be misleading because the number will go up not only with greater prevalence but also with greater testing activity. Two areas could have identical true rates of infection, but the area that tests more will report more cases.

So is Santa Clarita ready to reopen?

Depends on who you ask.

[1]Twice in as many days, he has mentioned carving a separate county out of north LA County as not being the craziest of ideas.