7 May 2020 – Thursday – #53

Everyone is excited about llamas. Meanwhile, Republicans are like ostriches putting their heads in the sand. The results are not hard to predict.

The White House is deep-sixing CDC guidelines on how to relax Covid-19 restrictions.

Florida is covering up Covid-19 deaths.

Arizona is opening up for business and shutting down its Covid-19 science panel.

The US is becoming a Covid-19 Tale of Two Countries, the Blue US and the Red US. That explains why the overall US mortality trend fools me each day. Some days I think it’s finally flattening, others not so much.

Covid-19 mortality per million people by country.

Every country on the chart above has a clear flattening inflection in its Covid-19 mortality curve except Brazil and the US. By now, I would have expected an inflection in the US curve, so I looked for what might explain the lack of inflection.

It’s a red state versus blue state thing. Here’s a chart that makes that clear.

Covid-19 cases by early and late US states (Washington Post)

The US has two Covid-19 trends. States that had the most Covid-19 cases in early April are seeing their caseload decline as a result of social distancing. The rest of the states are seeing their Covid-19 caseload increase.

This explains why I haven’t seen an inflection in the overall US mortality curve, and probably won’t for at least a month. States like Texas, Georgia, and Arizona that are relaxing Covid-19 restrictions increase their upside risk in R, the viral infection rate. That, in turn, leads me to believe the increasing Covid-19 case trend (“Other states”) will get steeper rather than inflect down until there is a course correction by these states.

Of the early states in the chart, California, New York, New Jersey, and Massachusetts have Democratic governors and a combined population of 75 million, or 23% of the total US. The other three early states have Republican governors. Florida, Michigan, and Louisiana have a combined population of 36 million, or 11% of the total US.

In the “Other states” category, that leaves 23 states with Republican Governors and 20 with Democratic Governors. The red states in the climbing trend line have 120 million people, or 37% of the total US. The blue states have 97 million people, or 30% of the total US. Another way of looking at this is that about 1/3rd of the US population has sheltered in place to achieve a decline in Covid-19 caseload while the other 2/3rds of the population has increasing caseload. Most of the “Other state” population is in red states aggressively relaxing Covid-19 restrictions.

Of course, it’s difficult to predict what will happen as a result of changing Covid-19 restrictions. How difficult? Here’s a Harvard paper that discusses a Covid-19 outbreak model and below is a small part of what the model predicts. This chart shows Covid-19 infection for a population that does eight weeks of social distancing without corrections for possible seasonality.

Harvard Covid-19 transmission model for 8 weeks of social distancing without seasonality.
Red line = 20% reduction in R0, blue = 40%, green = 60%.

The models tell us a few things. One is that completely relaxing social distancing leads to an increase in R. That means states or countries relaxing social distancing either need to have thorough test, track, and quarantine programs in place, or need to measure the response of overall R to a set of relaxations and reverse the relaxations if R increases. The latter is the case here in Spain and will be for most of the world until testing ramps up enough so that tracking can be implemented. In the absence of either rigorous testing or overall R monitoring, R will increase and force another lockdown.

Another thing the model tells us is that we’re at the mercy of Covid-19 immunity in terms of strength and duration, neither of which we understand yet. Sweden makes an assumption in its effort to achieve herd immunity that such immunity is long-lasting, but those with mild cases of Covid-19 appear to generate a small immune response that may not last. Also, there are various reports of SARS-Cov-2 mutation to a more virulent form that is not only predicted to increase Covid-19 virulence and mortality, but may also defeat existing immunity.

The Harvard model also says seasonality is important. Again, we know nothing about Covid-19 seasonality other than similar viruses are seasonal. We know that Covid-19 was a catastrophe in Ecuador, which has a tropical climate.

There is a lot of uncertainty! But not at the White House!

Here is a Twitter post about the new White House model for Covid-19.

Republicans clinging to office need Covid-19 to go away. Unlike the Harvard model, the Republican Covid-19 model makes the whole mess disappear! The White House “improves visualization” by applying a cubic fit to the data. In other words, someone fiddled with Excel until they found the line fit function that suited Trump’s political visualization.

Unfortunately, if the Harvard model is close, it predicts that a quick relaxation of Covid-19 restrictions will lead to rebound in caseload in August or September. It would be unfortunate for Republican Covid-19 messaging to have ICUs overloaded in red states a month or two before the election.

But there are always the llamas to save us.

The researchers linked two copies of a special kind of antibody produced by llamas to create a new antibody that binds tightly to a key protein on the coronavirus that causes COVID-19. This protein, called the spike protein, allows the virus to break into host cells. Initial tests indicate that the antibody blocks viruses that display this spike protein from infecting cells in culture.

Science Daily, “Antibodies from llamas could help in fight against COVID-19, study suggests,” 1 May 2020

Researchers from UT Austin and National Institutes of Health and Ghent University in Belgium have found an antibody in llamas that binds to the so-called spike protein that allows SARS-Cov-2 to hijack cells in order to replicate.

I hope it works!

But I’m going to be a Debby Downer. The soonest we should be planning for something brand new like a vaccine or a monoclonal antibody is later next year.

Should some of the more “scalable” vaccines prove to be protective, it’s conceivable that they could be made at existing plants, rather than require the construction of whole new facilities. Production of this type of candidate could reach hundreds of millions of doses within about a year, Emini said. But any vaccines that would require bricks-and-mortar construction is obviously going to take longer to reach those output levels.

Stat, “Mounting promises on Covid-19 vaccines are fueling false expectations, experts say,” 6 May 2020

Excited researchers issuing pre-prints have got my Mom convinced we’ll have something later this year. The reality is that at the scale we need to make the world safe again, we’re at least a year away from protection.

An important political note about vaccines. Of the eight vaccines currently in human trials, four are in China. If Trump got you worked up about how China was so terrible during the Covid-19 outbreak (you trusted something Trump said?), you may be singing a different tune this summer if China has the only vaccine that works. We have to work together to solve Covid-19 problems because we’re going to have to share the solutions.

I really wanted to talk about the economy today, but that will wait for tomorrow.

In the meantime, Brad wants to remind you that it’s not Trump who will save us from Covid-19. It’s Dolly Parton!

So, for Dolly’s sake, please stay at home and get back to work!

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