March 16, 2020 | By


The following was recounted to me by an epidemiologist:

A female diplomat from the Philippines to the UN, Justin Trudeau’s wife, the Arsenal manager, a Chelsea player are positive for coronavirus.  I can’t see sporting events continuing.

New York state banned all gatherings with 500 or more people.  Many churches have suspended worship services globally including The Vatican.  Japan again insisted that the Tokyo Olympics will go ahead this summer, hours after Donald Trump added to speculation that the coronavirus pandemic could force them to be postponed or cancel.  Disney World Resort in Florida, and Disneyland Paris announced they would close through the end of the month, starting at the close of business Sunday.

Ghana and Gabon confirmed their first cases, becoming the 9th/10th countries in sub-Saharan Africa to register positive cases.  There are very few cases there or in South America, and they are mainly in travelers.  Australian Prime Minister Scott Morrison advised against non-essential travel, and starting Monday gatherings of over 500 people will be canceled.  He said he would be attending a football match this weekend.  The advice did not extend to schools and universities.  The Australian Grand Prix was cancelled, after a member of the McLaren Racing Team tested positive.

More tests being hampered by lack of buffer to extract viral nucleic acids.

Just to be clear regarding this R0 thing, and this is very basic but works:

R0 (R zero) is a measure of how many other people 1 person infects.

R0 = 1: means 1 infected person transmits to 1 other person.  If that happens every 5 days (time from infection to transmission), it takes nearly 5 million years to infect everyone in the US or Europe.

R0 = 2: 1 person infects two people who then infect 4, 8, etc until 135 billion people have been infected in about 6 months.

R0 <1: Transmission peters out and never really takes hold.

R0 is a function of social distancing.  Take a highly contagious (could still be asymptomatic) person from Italy, put them in a room with 350 other pharma colleagues from Biogen at the Cowen conference in Boston (which is what happened) to shake hands, hug, stand close, huddle together, and that person’s R0 can be 70.  Take the same person and put him or her on a desert island and their R0 will be zero.

Currently, in warmer weather, R0 appears to be <1. The evidence for that could change, if we see sustained transmission in warm weather, it will show evidence that R0 >1 and needs to be strongly contained.  We haven’t seen that yet but we are looking for it.

In crowded cities with cooler temperatures, R0 can be well above 2.

People who are taking precautions, staying 3 feet from others, sanitising things like some people do etc until we learn more are part of the group keeping the R0 <1.  Thosegoing to crowded bars in known hot spots, sitting v close, kissing hi, and shaking hands, are at risk of driving spread in the R0 >2 group.

There’s an interesting latitude based twitter map going around showing the major infected areas with places in Chinese:

Picture 1

It’s interesting that the hot spots track in a narrow band of coolish temperature; it could portend a summer of ‘COVID cooling’.  The map excludes the UK hotspot, but temperature there seems similar, but maybe as mentioned by Pete it’s the rain. A lift is not guaranteed as there could be other explanations for this pattern, and If there is a meaningful warm weather community outbreak, this thesis will be broken.  However, if it does play out, we might also see a reversal of intense COVID regions to cold ones as the seasons change, and vice versa, which could precipitate new crises in new countries.  Keep in mind, many cases in warm cities are people returning from hot zones.  From what I can tell, they might have led to a couple of other cases, but with an R0 well below 1.  Alternatively, they might be transmitting undetected due to lack of tests.  Also, you can’t treat the US like a big lump.  Some of if it is in warm zones, some is in cooler. If temperature/climate is key, we might have a couple of rough months from dense cool zones, but limited spread beyond.  As it warmscases may dissipate, but as the next cool season arrives, there may be renewed fears.  Many epidemiologists predict it will return aggressively the next flu season. This could lead to a W shaped, or saw-toothed recovery.  No one knows.