Montreal City Weblog

Kate 12:37 on 2020-05-16 Permalink Reply  

• david111 13:06 on 2020-05-16 Permalink

  It’s still unclear what effect the warmer weather and sun will have, and how much it’ll mitigate the spread, but there’s some pretty good reason to hope/expect that the change in season will make a second wave less likely.

  From the Washington Post today:

  A new working paper and database put together by researchers at Harvard Medical School, MIT and other institutions examines a host of weather conditions, from temperature and relative humidity to precipitation, at 3,739 locations worldwide to try to determine the “relative covid-19 risk due to weather.” They found that average temperatures above 77 degrees (25 celsius) are associated with a reduction in the virus’s transmission.

  Each additional 1.8-degree (.3 celsius) temperature increase above that level was associated with an additional 3.1 percent reduction in the virus’s reproduction number, called R0, and pronounced “R naught.” That is the average number of new infections generated by each infected person. When the R0 drops below 1, an epidemic begins to wane, although it doesn’t happen overnight.

  https://www.washingtonpost.com/health/summer-weather-could-help-fight-coronavirus-spread-but-wont-halt-the-pandemic/2020/05/15/70ee90e2-95f6-11ea-9f5e-56d8239bf9ad_story.html

  The landing page for that study is here: https://projects.iq.harvard.edu/covid19

  This is, of course, great news if it’s borne out. And goes some way to explain why all those southern US states haven’t been as hard hit, and also why Australia (which was in summer/fall for most of this process) escaped relatively unscathed. Also explains why some of these southern states in the news are not seeing a giant surge in cases as they’ve “re-opened.” https://www.axios.com/coronavirus-cases-map-high-risk-states-8ceeaa05-cc07-4e8b-b9f4-df3a3315f143.html

  This is, of course, dreadful news for my beloved Argentina and Uruguay, which are entering their winter now and probably will need to keep travel down for several more months. Eat a steak for me, guys!

• Alison Cummins 08:57 on 2020-05-17 Permalink

  David,

  Yes, warm weather will likely reduce transmission. We already know the coronavirus is seasonal. From WebMD on colds:

  “How and When They Strike

  “Cold viruses have a lot in common, but each type has its own style, too.

  “Rhinovirus. This bunch is most active in early fall, spring, and summer. They cause 10%-40% of colds. You’ll feel plenty miserable when you catch one, but the good news is they rarely make you seriously sick.

  “Coronavirus. These tend to do their dirty work in the winter and early spring. The coronavirus is the cause of about 20% of colds. There are more than 30 kinds, but only three or four affect people.”

  So if this coronavirus is like other human coronaviruses, it peaks in winter and early spring. Immunity also lasts about eight months so we can get the same coronavirus cold every year.

  This would make summer a perfect time to contain the virus. Maintain lockdown and pursue aggressive contact tracing now, and we can be ready to go by fall! We can be like Australia! Woot!

  Instead we’re trying to use the weather to maintain status quo. Warm weather reduces transmission, so we do things that increase transmission. Cool. Status quo of top-seven worst hit cities in the world is definitely where we want to be. Maybe we can be number one next year!?

• Tee Owe 12:23 on 2020-05-17 Permalink

  Alison
  *We can be like Australia* – their summer is now over, they had a Covid outbreak and quite a few deaths – is that what you meant? Or did you mean that they locked-down and beat Corona even in their summer? We in the northern hemisphere tend to forget that half the geographical world are in an opposite season to us, and I don’t see Brazil as being particularly protected by it being summer there.

• david100 13:46 on 2020-05-17 Permalink

  Your spike in Brazil just started, and May is their equivalent to our November.

  Alison – With proper social distancing, hand-washing, testing, and isolation of those who’ve tested positive, a nice hot summer seems like it should probably do the trick. No need to bankrupt the tens of thousands of companies that are currently on life support, really plunge us into a depression, and force Trudeau and his gang to dump even more tens/hundreds of billions onto the federal debt.

• Kevin 16:04 on 2020-05-17 Permalink

  Unfortunately our provincial govt has proven it is incapable of testing, tracing, and isolating the sick.

• Kevin 19:09 on 2020-05-17 Permalink

  David or Douglas
  Whichever of you had an antibody test: bettet check on it. Almost all of those tests have been rejected/recalled because of too many false positives and negatives

• david100 20:58 on 2020-05-17 Permalink

  David – Douglas is someone else.

  I took the Abbott antibody test, which isn’t getting the variety of results as the Abbott instant covid 19 test, which is a non-molecular active infection test.

• Alison Cummins 14:33 on 2020-05-18 Permalink

  Tee Owe,

  You’re right, Australia is experiencing a growth in cases now that it’s getting into fall. It shows quite clearly in this handy-dandy chart. (Set to logarithmic if you can’t see Australia.)

  https://datagraver.com/corona/#/?regions=australia%3Ahex000000,british%20columbia%3Ahex4CAF50,canada%3Ahex7B1FA2,new%20south%20wales%3Ahex5D4037,northern%20territory%3Ahex407D82,ontario%3AhexF44336,quebec%3Ahex2196F3,rwanda%3AhexE1DD34,tasmania%3AhexA1887F,victoria%3Ahex795548,new%20york%3Ahex303F9F&logScale=false&perCapita=true&cutYaxis=true&cumulative=false&types=2,3&mappingType=fatalities&mappingMaxDays=200&mappingStartNumber=1&mappingNumberStyle=relative&mappingEventType=lockdown&mappingDate=2020-3-14&smoothening=7&description=Tool%20for%20comparison%20on%20Covid%2019%20development%20for%20countries%20and%20regions

  As you can see from this other handy-dandy chart, Australia had a death on May 13 after six days of 0 deaths. *Definitely* a second wave hitting.

  https://www.worldometers.info/coronavirus/country/australia/