Kansas COVID-19 Update, Week 63

Our Delta wave nightmare continues to dissipate. New cases in Kansas are down to their lowest level since late July, and the downturn is slowly but surely opening up more hospital beds, especially in the Kansas City area. 

The Good: Total COVID-19 hospitalizations in Kansas are down from about 600 last week to 556 this week. ICU availability is right at 20% in the Kansas City area, which is about the minimum cushion we want to see. Wichita's ICUs are still overcapacity and operating on surge plans, but the trends are good there too — COVID hospitalizations are down from 187 to 157 and COVID patients in ICU are down from 73 to 63. 

The Neutral: The infection reproduction rate, Rt, remained at 0.93 for the second week in a row. This bolsters my suspicion that the brief drop to 0.85 two weeks ago was some sort of data fluke. The Rt seems to be pretty steady at 0.93 in Kansas. It would be nice if it were lower, but that's still low enough for cases to continue declining.

The Ugly: Test positivity rose from 28.3% to 31.6% this week, according to Johns Hopkins. That's fourth-worst in the country behind Idaho, Oklahoma and Iowa. It's a bit disconcerting that this number is going up, because it degrades some confidence in the new case numbers. We're certainly missing some infections, but I don't think it's enough to change the overall trajectory.

Bonus: There is much discussion about whether immunity from prior infection is as good or better than immunity from vaccination. The evidence we have now suggests that immunity from prior infection is highly variable - if you recovered from a severe infection, you probably have just as much protection as a vaccinated person, at least in the short term. If you had a mild case, you probably don't. And the best possible protection comes from a combination of both prior infection AND vaccination. That means there's no reason to turn down the vaccine just because you've already had COVID, given the safety profiles of these vaccines. 

To see a breakdown of the antibodies produced by four different COVID vaccines, compared to those produced by prior infection, click on the "Full text" tab of this study, and look at Figure 1. The green dots are Pfizer, the purple dots are Moderna, the orange dots are AstraZeneca (which is not currently available in the USA) and the blue dots are Johnson & Johnson. The gray dots are antibody levels from prior infection (convalescent). The gray dots (prior infection) are all up and down the antibody scale — some very high and some very low. Whereas, after two shots of the Pfizer or Moderna vaccine, the green and purple dots are much more clumped together, and clumped together at a higher level than most of the gray dots. And that's even without the third-shot boosters that are now rolling out, which dramatically increased antibody levels in trials. The other two vaccines are a different story. Based on this study (which, it should be noted, has not yet been peer-reviewed), one could make a good argument that prior infection usually provides protection that's equal to or better than the AstraZeneca or Johnson & Johnson shots. But the two mRNA vaccines (Pfizer and Moderna), which make up the vast majority of COVID shots given in the USA, provide better protection than almost any prior infection.