1/8 - “There is overwhelming evidence that inhalation of severe acute respiratory syndrome coronavirus 2 (#SARSCoV2) represents a major transmission route for coronavirus disease 2019 (#COVID19) science.sciencemag.org/content/370/65…
2/8 - “We must clarify the terminology to distinguish between aerosols and droplets using a size threshold of 100 µm, not the historical 5 µm. This size more effectively separates their aerodynamic behavior, ability to be inhaled, and efficacy of interventions.”
3/8 - “Viruses in droplets (larger than 100 µm) typically fall to the ground in seconds within 2 m of the source and can be sprayed like tiny cannonballs onto nearby individuals. Because of their limited travel range, physical distancing reduces exposure to these droplets.”
4/8 - “Viruses in aerosols (<100 µm) can remain suspended in the air for many seconds to hours, like smoke, and be inhaled. They are highly concentrated near an infected person, so they can infect people most easily in close proximity...”
5/8 - “... But aerosols containing infectious virus can also travel more than 2 m and accumulate in poorly ventilated indoor air, leading to superspreading events.”
6/8 - “Individuals with #COVID19, many of whom have no symptoms, release thousands of virus-laden aerosols and far fewer droplets when breathing and talking. Thus, one is far more likely to inhale aerosols than be sprayed by a droplet...”
7/8 - “...So the balance of attention must be shifted to protecting against airborne transmission.”
8/8 - “In add. to mandates of mask-wearing, social distancing,and hygiene efforts,we urge public health officials to add clear guidance about the importance of moving activities outdoors, improving indoor air using ventilation and filtration,and protection for high-risk workers.”
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2/21. Switzerland will be experiencing a rapid and worrying surge in its #COVID19 epidemic activity at high levels, with low levels of mortality, for 7 more days.
3/21. Italy will be experiencing a rapid and worrying surge in its #COVID19 epidemic activity at high level, with increasing low levels of mortality, for 7 more days.
1/6. The USA, Oct. 17 to 23 - Will be experiencing a rise in its #COVID19 epidemic activity at high levels, with high-medium mortality for 7 more days.
New risk map and 5 states detailed.
Data: Johns Hopkins Univ. renkulab.shinyapps.io/COVID-19-Epide…
Powered by @ISG_UNIGE & @SDSCdatascience
2/6. New York will be plateauing in its #COVID19 epidemic activity at medium levels, with low levels of mortality, for 7 more days. A situation apparently better controlled than currently in Western Europe.
3/6. Texas will be plateauing at high level of its #COVID19 epidemic activity, with decreasing although still high levels of mortality, for 7 more days.
1/5 - Un changement de stratégie de recherche des contacts s’impose en urgence. À Genève on ne trace les contacts jusqu’à maximum 48h avant les premiers symptômes (“forward tracing”recherche prospective des contacts). Mais ce n’est pas assez performant de faire ainsi...
2/5 - ...Il faut plutôt rechercher en priorité dans les 12-14 derniers jours quels ont pu être le ou les contact(s) contaminant(s) et s’arrêter d’abord sur celui (ou ceux) qui aurai(en)t pu être à l’origine d’une super-propagation (megaclusters). Et se focaliser sur ceux-là...
3/5 - Exercice pratique : Mme X, 30 ans, détectée positive. Elle vit seule, prend le bus 2 jours/sem pdt environ 25 min pour aller au travail, précautionneuse, masquée.
Les questions à poser : avez vous été à la cafétéria, restaurant, bar, théâtre,cinéma,culte,club de sport,...?
2/21. Switzerland will be experiencing a rapid and worrying surge in its #COVID19 epidemic activity at high levels, with increasing although still low levels of mortality, for 7 more days.
3/21. Italy will be experiencing a rapid and worrying surge in its #COVID19 epidemic activity at high level, with increasing low levels of mortality, for 7 more days.
2/21. Austria is experiencing a worrying surge in its #COVID19 epidemic activity at high levels, with increasing medium levels of mortality.
3/21. Italy will be experiencing a rapid and worrying surge in its #COVID19 epidemic activity at high level, with increasing low levels of mortality, for 7 more days.
1/8 - Il y a deux modalités de traçage des contacts:
a) Traçage prospectif, classique, on recherche les contacts du cas;
b) Traçage rétrospectif,”à la japonaise”,on recherche qui a contaminé le cas.
La priorité des priorités c’est de privilégier b) et ne faire a) que si on peut.
2/8 - Le fondement théorique vient du paramètre k de dispersion, élevé pour la grippe (de dynamique homogène) et faible pour le #SARSCoV2 dont la dynamique est hétérogène, émerge en clusters et en événements super-propagateurs: 10 à 20% des contaminations drive toute la pandémie.
3/8 - Si 80-90% des cas contaminent 0 ou 1 cas, on n’a pas à se fatiguer à tracer leurs contacts. Ils ne nous inquiètent pas. En revanche, il faut tout mettre en œuvre pour stopper la propagation causée par les 10 ou 20% restants, à commencer par les identifier. Comment faire ?