covid 19 infection surge

1. COVID 19 in NEJM ….

2. Aerosol and surface stability of CoV2
Published in Apr 19, 2020

3. Objective -
1. Evaluation of stability of SARS-CoV-2 & SARS-CoV-1 in aerosols and
on various surfaces ,
2. Estimation of their decay rates using a Bayesian regression model

4. Methodology
• Aerosols (<5 μm) containing SARS-CoV-2 or SARS-CoV-1 were generated with the use
of a three-jet Collison nebulizer and fed into a Goldberg drum to create an aerosolized
environment
• The inoculum resulted in cycle-threshold values between 20 & 22, similar to those
observed in samples obtained from the upper and lower respiratory tract in humans.
• Data consisted of 10 experimental conditions involving two viruses in five
environmental conditions- aerosols, plastic, stainless steel, copper, and cardboard .
• All experimental measurements are reported as means across three replicates

5. Observations
• SARS-CoV-2 remained viable in aerosols throughout the duration of experiment (3
hours), with a reduction in infectious titer from 103.5 to 102.7 TCID50 /L of air , similar
to CoV1
• SARS-CoV-2 was more stable on plastic and stainless steel , viable virus was detected up
to 72 hours
• The virus titer was greatly reduced from 103.7 to 100.6 after 72 hours on plastic &
103.7 to 100.6 after 48 hours on stainless steel .
• On copper & cardboard , no viable SARS-CoV-2 was measured after 4 & 24 hours
respectively

6. Titers of Viable Virus
The titer of aerosolized viable virus is expressed in 50% tissue-culture infectious dose (TCID50) per liter of air.
Viruses were applied to copper, cardboard, stainless steel, and plastic maintained at 21 to 23°C and 40% relative
humidity over 7 days
All samples were quantified by end-point titration on Vero E6 cells. Plots show the means and standard errors (I
bars) across three replicates.

7. Predicted Decay of Virus Titer
Regression plots indicate the predicted decay of virus titer over time; the titer
is plotted on a logarithmic scale.

8. Half-Life of Viable Virus
violin plots indicate posterior distribution for the halflife of viable virus based on the estimated exponential
decay rates of the virus titer. The dots in dicate the posterior median estimates, and the black lines indicate a
95% credible interval

9. Take home points
• Aerosol & fomite transmission of SARS-CoV-2 is plausible, since the
virus can remain viable and infectious in aerosols for hours and on
surfaces up to days (depending on the inoculum shed)
• High viral loads in the upper respiratory tract and the potential for
persons infected with SARS-CoV-2 to shed and transmit the virus
while asymptomatic – cause of epidemiologic difference in CoV2

10. Coagulopathy & APL antibodies in Covid- 19
Published -

13. • APL antibodies can also arise transiently in patients with critical
illness and various infections.
• The presence of these antibodies may rarely lead to thrombotic
events that are difficult to differentiate from other causes of
multifocal thrombosis in critically patients

14. nejm.org on April 19, 2020

15. • Myocardial injury with ST-segment elevation has been observed in
patients with coronavirus disease 2019 (Covid-19)
• We identified 18 patients with Covid-19 who had ST-segment
elevation indicating potential acute myocardial infarction

18. Learning points
• In this series of patients with Covid-19 who had ST-segment
elevation, there was variability in presentation, a high prevalence of
nonobstructive disease, and a poor prognosis
• Myocardial injury in patients with Covid-19 could be due to plaque
rupture, cytokine storm, hypoxic injury, coronary spasm,
microthrombi, or direct endothelial or vascular injury
• Myocardial interstitial edema has been shown on magnetic
resonance imaging in such patients.