Peter Lombard MD
Guam COVID update for April 9th, evening edition.
Good evening Guam! Good news: only 3 new cases today bringing our 7 day rolling growth rate down to 1.07x. Using this number, our ICU 15 bed break point date is pushed out to T+12 days in the future. Good but not good enough. We’re averaging 6 to 7 new patients a day if you average the past 7 days, while only recovering 2 to 3 per day. I have designed a crude model that shows we need to be in the 1.02x to 1.04x range to be able to sustain our COVID sick within the constraints of our healthcare system.
Six days ago on April 3rd, the official worst-case projections had us at 75 admissions by April 10th (tomorrow). That’s not happening, obviously. We only have 90-ish active cases in total. Looking at the model that was used for these predictions and I think we have reached the point where we *have* to say that the assumptions made in that model were too conservative. WAY too conservative. And that’s ok.
But now can we go back to the original model, which was based on an appropriate SEIR epidemiologic model and ask ourselves how we can revise the parameters to make it look more appropriate to what we’re seeing today? Initially we used 2.6 as the R0 value and a 20% reduction in R was assumed after interventions, a value of 2.2. This gave the doomsday predictions. (Remember R is the reproductive number. An R of 3 means every person infected will infect 3 people.)
It turns out you can go back and plug in numbers that make sense with reality. You keep R0 the same, but if we actually improved the R value by 50% for the first week down to 1.3, then with better compliance with social distancing, we improved R by about 60 to 65% thereafter to a value close to 1, I think this actually gives us a pretty good estimation of where we are today. I’m hoping Dr. Cruz and Dr. Cabrera and the DPHSS epidemiologists are seeing something similar.
And what would that tell us about the future? Well at 60% reduction the new R value is very close to 1. So if we fluctuate a little above and/or below 1, we will NOT overwhelm our healthcare resources. The further below 1 we can take this, the better off we’ll be, and this is all dependent on how well we can continue the social distancing measures as we try to resume our normal lives. And dependent on how well we deal with local sparks, which will inevitably come.
Are we peaking? If we’re not peaking now I think we will be within a week. I split the new cases down into 5 day cohorts since March 15th (Slide 5). In the most recent 5 day grouping (April 4-8) we have seen our new cases continue to rise, but the rate of increase has been declining. If we have less than 36 cases over the next 5 days (about 7 per day) then we will be at the peak. I’ll be able to do a 7-day cohort analysis after the 4/11 data.
Lastly I have to touch on the DPHSS announcement about the clusters. We’ve been asking for this type of information from day 1, and now that it was provided, all it does is raise more questions. At least in the context it was provided. What did they expect? They asked the public to contact public health if we thought we might be in any of the group settings. Settings such as “a health clinic” or “a hotel”. No dates, no times, no other specifics. If this is perceived as being a little bit ridiculous I hope they understand why.
I get it, they want to be seen as providing more details and being more transparent. Well I’ll give them a B for effort but a D for execution, as constructively as that can be done. There are two separate issues, one is the decision to release more details, and the other is how you do that if the details are vague.
For the first issue, if there was any internal debate about whether or not to be FULLY transparent, I hope there were some voices and arguments for more robust transparency. Because you know what, the safety of the public should supersede any other considerations, full stop. Without knowing any other details, whatever fears swayed them from providing more information should have been overruled by the need to inform the public in the interest in finding more cases. I don’t think you can reasonably argue finding *all* potential people infected isn’t the #1 priority. I also don’t think you can argue that effective tracing alone is better than effective tracing PLUS an informed public. More people potentially affected by each cluster can be identified because everyone will have the opportunity to consider how they might have been affected, even if they are 2 to 3 degrees away from the location involved. There’s no way tracing would be able to investigate to the same depth.
For the second issue, if there are valid reasons to not provide more detail, they could at least attempt to explain them to us. Don’t treat us like we’re dullards, at least give us the benefit of some sort of explanation that we can try to come to terms with. Sure some of us are going to be more understanding than others… but if it was the fear of backlash that kept them from telling us more information, how is that more important than finding more people that might have been affected? Then there’s the whole issue of the public finding out anyway, and how much worse that’s going to look for them.
I wonder who makes the final call on these matters. I think most of us want to give the benefit of the doubt, we don’t know what they know and that might make all the difference in the world. But if they want to be perceived in a better light, they’ve got to at least try to send a better message.
#Masks4All #Covid19 #coronavirus #flattenthecurve
(charts accessible at https://docs.google.com/presentation/d/1YmBfAcbLcCk3TUdP4zV4oOTqipp_p32-Vfdh3IJ2XCE/edit?usp=sharing)