COVID-19 Update 18: When are patients really infectious?

Individuals are infectious with COVID-19 when they're shedding the virus, which means that the virus replicates in the cells of their upper or lower respiratory tract. In this video, we will examine published articles discussing viral shedding, the incubation period (mean incubation period was 5.2 days) and the serial interval, by examining the results of 77 COVID-19 transmission pairs.
The study found that infectiousness starts 2.3 days before symptom onset. That patients are most infectious 0.7 days before symptom onset.They also found that 44% of infectiousness or infections occurred in the pre-symptomatic phase making it difficult to track.
#medmastery #coronavirus #COVID19 #sarscov2 #coronaviruschina #coronavirustruth #coronavirusdeaths #WHO #wuhan #infection #pandemic #publichealth
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Links for reference:
www.nature.com/articles/s4159...
www.nejm.org/doi/full/10.1056...
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More updates by Dr. Wiesbauer:
COVID-19 Update 1: How to tell if a pandemic is likely to occur or not-R0 and the serial interval: • COVID-19 Update 1: How...
COVID-19 Update 2: How to stop an epidemic - Herd immunity: • COVID-19 Update 2: How...
COVID-19 Update 3: Symptoms of COVID-19: • COVID-19 Update 3: Sym...
COVID-19 Update 4: Clinical characteristics of COVID-19: • COVID-19 Update 4: Cli...
COVID-19 Update 5: Estimating case fatality rates for COVID-19: • COVID-19 Update 5: Est...
COVID-19 Update 6: Seasonality: will COVID-19 go away in the summer?: • COVID-19 Update 6: Sea...
COVID-19 Update 7: This is probably the most important picture of the whole Coronavirus-epidemic: • COVID-19 Update 7: Thi...
COVID-19 Update 8: Zinc and chloroquine for the treatment of COVID-19?: • COVID-19 Update 8: Zin...
COVID-19 Update 9: Hydroxychloroquine and azithromycin for the treatment of COVID-19-Review of study by Didier Raoult: • Hydroxychloroquine and...
COVID-19 Update 10: Is COVID-19 an airborne disease? Will we all need to wear face-masks against SARS-CoV-2? • COVID 10: Is COVID-19 ...
COVID-19 Update 11: How exactly the coronavirus becomes airborne. • COVID-19 Update 11: Ho...
COVID-19 Update 12: Attack rates of COVID-19 depend on face-to-face time spent with infected persons: • COVID-19 Update 12: At...
COVID-19 Update 13: Randomized Controlled Trial of Hydroxychloroquine in Patients with COVID-19: • COVID-19 Update 13: Ra...
COVID-19 Update 14: Are children contributing to the spread of COVID-19? • COVID-19 Update 14: Ar...
COVID-19 Update 15: Can we disinfect and reuse N95 masks?:
• COVID-19 Update 15: Ca...
COVID-19 Update 16: Effectiveness of surgical masks for prevention
• COVID-19 Update 16: Ef...
COVID-19 Update 17: How an app can get us out of lockdown
• COVID-19 Update 17: Ho...
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Useful resources:
For checking daily developments of cases, deaths and more:
gisanddata.maps.arcgis.com/ap...
www.worldometers.info/coronav...
Other useful resources:
Journal Watch:
www.jwatch.org/na51020/2020/0...
New England Journal of Medicine:
www.nejm.org/coronavirus
Github collaboration:
github.com/midas-network/COVI...
CDC:
www.cdc.gov/coronavirus/2019-...
WHO:
www.who.int/emergencies/disea...
Nucleuswealth:
nucleuswealth.com/articles/up...
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Speaker: Franz Wiesbauer, MD MPH
Internist & Founder at Medmastery
LinkedIn: / franzwiesbauer
PubMed: www.ncbi.nlm.nih.gov/pubmed/?...
Check out our course library and register for a free trial account: www.medmastery.com/user/register
Facebook: / medmastery
Twitter: / medmastery
Please Note: Medmastery's videos, medical lectures, medical illustrations, and medical animations are for medical education and exam preparation purposes, and not intended to replace recommendations by your doctor or health care provider.

[@jaehochoi5064]

Personal bookmark 2:20 Transmission pairs 7:06 infectiousness starts 2.3 days before symptom onset, most infectious on 0.7 days before symptom onset, and almost no infectiousness on seven days after symptom onset

[@MrMetalWarlock]

thanks

[@smalltalk1373]

Thanks

[@jendrizzyy]

Thanks, why couldn’t he just say it like that instead of all this scientific mumbojumbo

[@drpardeepkapoor2562]

As usual; excellent presentation. This concept of pairs is entirely new to me. Great

[@guillelainez]

Thank you for posting these great videos! Im a last year medical student from Honduras!

[@syr1981]

Amazing vedio as usual.Thanks a lot❤

[@quadruplelatte]

And why everyone should be wearing masks.

[@AwesomeBlackDude]

Many folks would just circumvent the tracking app if it (ever) was mandatory. One solution that actually worked... UBI, this the government won't implemented their greed are too high. Jim Crow and Hitler couldn't never imagine nor accomplished this feat.

[@zmartkooky244]

masks are way more complex than the layman face-rag fundamentalist believes. The right mask in the right way for the right time in the right place helps a little, some times a bunch. Problem is the "right" part. You have to know which mask to wear when, how long to wear it, when to dispose it (2 hrs), how to place and remove, no to touch it, no to put it in the chin, replace when entering or leaving an area, etc, etc, etc. Do any of those wrong and you are making things worse, nut just a little less bad. A correct sneezing/coughing technique is way more efficient, easy and secure than the face rags.

[@AndysGeneral]

@@zmartkooky244 you're missing a big part of the equation. People speaking close to you

[@ah6169]

Props Doc !! This is the detailed OG breakdown people need....Stay Fly

[@LifeForceChannel]

60 days of quarantine/ safedistancing, mask wearing and all other measures in place Should have already resolved (all seriously ill) and others would have recovered. And life can and should go on.

[@kennyw871]

The only civilization I know that could pull-off your suggestion would be ant colonies! There's just enough selfish people in the world to prevent this from happening. Look at human behavior around you, you'll see what I mean. Then study an ant colony and see how cohesive and organized they are. How knows, maybe that's how ants handle potential pandemics?

[@lifecontent6525]

@@kennyw871 I agree. I am all for freedom, but in some instances (like world health) If everyone would stay in their homes and let groceries be delivered by a small group in hazmet suits for about 60 days, and the ones with active covid be cared for in hospitals (for the severe cases) until it was completely resolved. We could all have real freedom once again after it completely died as there was no where for it to host. Unfortunately that will never happen. I would sacrifice for 60 days in a NY heartbeat, I want this over with! I had covid and dr said I was uncontagious after 7 days from getting the positive test. I have stayed in for 21 days because I dont trust it is not to be contagious. I feel normal but dont trust this disease and the last thing I want to do is spread it. BTW I was and am very meticulous w mask wearing and hand washing as well as disinfecting all doorknobs, phones, tv remotes, light switches, fridge , microwave and oven handles every day. I have clorox wipes everywhere. I really dont know how I caught it but I did. It will eventually resolve but it will take much much longer. Stay safe!

[@TheProdiKaLiSon]

@@lifecontent6525 so it's a year later....more people have died under Biden, inflation through the roof, and nobody wants to work. What say you now about all this? Or are you still a paranoid freak about covid? So sorry your commie wet dream of men in hazmat suits didn't come to deliver groceries like you wanted! Lol good lord, we need to commit people back to the psych wards asap!

[@bartekkwiatkowski4278]

what about this study ? Current data says that sympthoms start usually 5 days after transmission and viral load peaks when symptoms onset then is slowly dropping .

[@KarineLago]

REALLY GOOD! thanks

[@christinecapota9165]

Thanks! I have a follow up question: I heard a person has a latency period, where they are not contagious for 24-48 hours after being exposed to the virus. Is this true? I understand you can calculate a certain amt of time before symptoms, but can you calculate infectiousness from the time you are exposed to enough virus. Thanks!

[@stymell]

You ever figure out an answer to this question?

[@christinecapota9165]

​@@stymell No, I didn't. I found the original article but it's referential and I couldn't find citations www.weizmann-usa.org/news-media/in-the-news/four-days-of-work-followed-by-10-days-of-lockdown-could-help-prevent-another-wave-of-infections. I've asked a few doctors and scientists since then, and the answer I got was we don't know. All of the research on covid-19 to date measures contagiousness from Day 1 of SYMPTOMS not EXPOSURE. So, people are most contagious 2-3 days before symptoms. No research to my knowledge has been done on contagiousness after exposure. My own interpretation of this, is that it's possible but less likely that someone would be contagious on Day 1 after exposure vs Day 3.

[@AndysGeneral]

That is very likely

[@respublikas]

If ive had a full contact with an infector at his prime of infectiousness when am i most likely to start being infectious aswell ?

[@hix9306]

So if someone in your house shows symptoms and test positive what do you do about it ? They’ve been in quarantine since we found out .

[@johnsopensky1586]

Pretty good presentation. Hence the rapid spread of this disease.

[@Unknown-bq2mw]

Can Someone Spread Virus Before coming of the symptoms ??? Please Tell?

[@kosh9639]

Contact Tracking like that is Futile & Intrusive... You would have to Quarantine everyone they know-- right from the beginning.. Regardless, of Initial Test-- to have any meaningful effect..

[@polypus74]

Thanks for all the great vids. Just for future reference, it's not pronounced "inTERval" but INTerval. I couldn't figure out what speaker was saying at first.

[@lg95]

I had no problems understanding him, especially as it SPELLED out interval before he started saying it. I believe he’s Austrian and has a light accent give him a break.

[@polypus74]

@@lg95 Was I being harsh? I don't thinks so. Now he might know how to pronounce it. I am also multi-lingual and appreciate it when people give me tips. Maybe grow a pair

[@datamesh8418]

As a statistic this sounds like an okay plan, but as a person, it sounds like it is not so much of a consolation that I have an app if I catch it but maybe a bonus for those who might get it from me. I don’t see this as a substitute for a lockdown or contact tracing. It is a thought experiment run with no friction but the real world obstacles, logistic, social, political, ethical, etc... makes this idea seem much less feasible or likely to be the home run the video presents it to be.

[@joecoates8383]

Can you catch it and spread it within 2 days

[@brendandoherty1283]

So is there any chance someone is still contagious After about 16 days of first showing symptoms? I wanna see my girlfriend before i go away, but she got corona a couple days before New Years

[@Unknown-bq2mw]

Can Someone Spread Virus Before coming of the symptoms ??? Please Tell?

[@Inkling777]

Digital tracing is both too much and too little. It's too much because it includes in the tracking list contacts that are so brief and casual they are unlikely to lead to an infection. It's too little in the sense that someone who rode an elevator might infect someone who also rides it fifteen minutes later even though they never got within a mile of one another. The contacts that matter are the ones that are extensive enough, say dining together, that people can remember them without digital tracking. That's where the effort should be devoted. It's also ridiculous to assume that the data could remain anonymous when it really matters. If a dictator took over, within days the contract tracing could included the names of who met who.

[@Unknown-bq2mw]

Can Someone Spread Virus Before coming of the symptoms ??? Please Tell?

[@arcticdragon104]

Yes

[@caitlynkelly6786]

Yes up to 2-3 days before showing symptoms

[@Unknown-bq2mw]

@@caitlynkelly6786 Thanks for The Information🤗

[@Unknown-bq2mw]

@@caitlynkelly6786 By the Way Can I get your Instagram ?

[@carolrocky9803]

I went to my new Doctor who was vaccinated and for the following 2 days I felt under my skin a sort of vibration, as if it was numb, but only on my skin, although I didn't have a fever, but did not feel well, I felt weak, and had to force myself to eat. She was much younger than my old Doc, and she mayhave been vaccinated months before. I didn't believe in the "shedding," before but I sure do now. I took a shower that morning, but I'm going to make sure to have at least 3 days of my bodies natural immunity on my skin before my next apointment

[@kcashion4735]

I know y’all are concerned about privacy and that’s why we don’t have the app that tracks covid cases, I propose that I am the person to run the app and store the data because I am just a normal person and I am not smart enough to abuse the knowledge.

[@fushiace5858]

Ct value is more reliable

[@user-fx1nt9jw8x]

in easy way they infected before the first infected show sign of symtop

[@mtidbit6343]

Lots of graphs and explanation... but by an Internal medicine doctor... not a virologist. There is a reason infectious disease is a specialized medical profession and Ill opt for their input and daily focus with the ever changing discoveries of this virus

[@OnlyOneAlly]

Can someone spread the virus on the day they were exposed

[@AndysGeneral]

Almost impossible

[@abag55]

No

[@Unknown-bq2mw]

@@abag55 I went to a friend's house, but after 2 days of my arrival, the symptoms of Corona started with her father , So in the Fear of Expose, I isolated myself and today is my 11th days and I am not getting any covid-19 Symtoms . Can I end my quarantine.

[@Unknown-bq2mw]

@@abag55 please Help 🙏

[@oibal60]

Ummmm nope #NoJab4Me I'll take #Ivermectin instead thankyou. #koolbeanz #EmergencyUseAuthorization #GeneTherapy

[@deldickens3rd]

So u recovered from the commons cold...want a 🍪? #StopTheHype

[@ankurhotnot]

Common cold does not kill 3 lakh plus people in 3 months.

[@deldickens3rd]

Ankur Bisht It’s not the common cold that’s killing them it’s the doctors misdiagnosing patients and utilizing improper treatment methods that weren’t needed in the first place. Besides I don’t trust all of their numbers as far as deaths go period from any medical facility...ie scenario A- I come in with corona symptoms but I die after utilizing a ventilator or other prescribed drugs that was given...they won’t say I died from the drugs or improper ventilator use they will just say I died from Corona. So all the numbers are skewed and just a means to get the ignorant to go get the vaccine once they produce it just like they normally do when they introduce a new vaccine to the public.

[@rafaelmatevos7177]

Trump 2024

[@bentrider]

Read the actual scientific studies. Then decide. wellnessdoc.com/1200studies