COVID19 Perspective
@covidperspectiv
Superb Q&A on coronavirus, Simply put a must read & guaranteed to learn something. Slightly foreboding... "We’ve been searching for an HIV vaccine for 35 years & we still don’t have one"
COVID19 Perspective
@covidperspectiv
45m
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@covidperspectiv
Two comments on this Q&A...
1. It was written the first week in March. The majority of the info is timeless, but there are a couple of dated references
2. We have an issue with the advice on masks. Please see our primer on face masks linked from our pinned thread up top
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100 Questions of Peter Piot, LSHTM Director
By:
Jay Walker, TEDMED Curator
Thursday 12 March 2020
Q&A with Peter Piot
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1. TEDMED: Let’s start with the basics. What is a virus?
A virus is a very tiny particle of RNA or DNA genetic code protected by an outer protein wrapper.
2. TEDMED: How common are viruses?
Viruses are everywhere. It’s amazing to realize that if you add them all up, all the viruses in the world weigh more than all the living matter in the world – including all of the plants, animals and bacteria. 10% of the human genome is derived from virus DNA. The Earth truly is a “virus planet!”
3. TEDMED: Why is it so hard to stop a virus from spreading?
Because virus particles are so incredibly small, billions can float on tiny droplets in the air from just one cough.
4. TEDMED: Exactly how small is a virus?
Tiny. Even with a regular microscope, you can’t see a virus. 100 million viral particles of the novel coronavirus, can fit on a pinhead. That’s how incredibly small they are.
5. TEDMED: What do virus particles do?
Virus particles try to insert themselves into living cells in order to multiply, infect other cells and other hosts.
6. TEDMED: Why do viruses try to get into living cells?
It’s how viruses “reproduce.” Viruses act like parasites. They hijack living cells in order to force each cell to make more viruses. When a cell is hijacked, the virus sends out hundreds or thousands of copies of itself. It often kills the hijacked cell as a result.
7. TEDMED: What does it mean to be infected with the new coronavirus, which scientists have designated “SARS-CoV2”?
It means that SARS-CoV2 has started reproducing in your body.
8. TEDMED: What is the difference between SARS-CoV2 and COVID-19?
SARS-CoV2 is the virus; COVID-19 is the disease which that virus spreads.
9. TEDMED: Is it easy for a virus to get into a living cell?
This depends in the first place whether the cell has the right receptor for the particular virus, just as a key needs a specific keyhole to work. Most viruses are blocked by our immune system or because we don’t have the right receptors for the virus to enter the cell. Thus, 99% of them are harmless to humans.
10. TEDMED: How many kinds of viruses exist, and how many of them are harmful to humans?
Of the millions of types of viruses, only a few hundred are known to harm humans. New viruses emerge all the time. Most are harmless.
11. TEDMED: On average, how many particles of the virus does it take to infect you?
We really don’t know yet for SARS-CoV2. It usually takes very little.
12. TEDMED: What does it look like?
SARS-CoV2 looks like a tiny strand of spaghetti, wound up in a ball and packed inside a shell made of protein. The shell has spikes that stick out and make it look like the corona from the sun. This family of viruses all have a similar appearance; they all look like a corona.
13. TEDMED: How many different coronaviruses affect humans?
There are 7 coronaviruses that have human- to-human transmission. 4 generate a mild cold. But 3 of them can be deadly, including the viruses that cause SARS and MERS, and now the new coronavirus, SARS-CoV2.
14. TEDMED: Why is it called the “novel” coronavirus?
Novel just means it is new to humans, meaning that this specific virus is one that we’ve never seen before. Our immune system has been evolving for 2 million years. But since our bodies have never seen this virus before, there has been no opportunity for humans to develop immunity. That lack of immunity, combined with the virus’s ability to spread easily and its relative lethality, is why the arrival of SARS-CoV2 is so disturbing.
15. TEDMED: How often does a novel virus emerge that we need to care about?
It’s rare… but it happens. Examples include the viruses that cause diseases such as HIV, SARS, MERS and a few others. It will happen again. The emergence of a novel virus is a very big problem … if it can easily spread among people and if it is harmful.
16. TEDMED: How easily does the new virus spread?
SARS-CoV2 spreads fairly easily from person to person, through coughs and touch. It is a “respiratory transmitted” virus.
17. TEDMED: Is there any other way that the virus spreads?
Recent reports indicate that it may also spread via fecal and urine contamination, but that requires confirmation.
18. TEDMED: How is this new virus different from the earlier known coronaviruses that spread SARS or MERS?
SARS-CoV2 is different in 4 critical ways:
First, many infected people have no symptoms for days, so they can unknowingly infect others, and we don’t know who to isolate. This is very worrisome because SARS-CoV2 is highly infectious.
Second, 80% of the time, COVID-19 is a mild disease that feels like a minor cold or cough, so we don’t isolate ourselves, and infect others.
Third, the symptoms are easily confused with the flu, so many people think they have the flu and don’t consider other possibilities.
Fourth, and perhaps most importantly, the virus is very easy to spread from human to human because in the early stages it is concentrated in the upper throat. The throat is full of viral particles so when we cough or sneeze, billions of these particles can be expelled and transmitted to another person.
19. TEDMED: I thought the virus leads to pneumonia? How is the throat involved?
The disease often starts in the throat (which is why tests often take a swab from the throat) and then as it progresses it moves down to the lungs and becomes a lower respiratory infection.
20. TEDMED: I hear the word “asymptomatic” used a lot. What does it mean?
It simply means having no symptoms.
21. TEDMED: Are you saying that someone can be infected with the new virus and never show symptoms at all?
Unfortunately, yes. Many infected people do not show any symptoms for the first few days and then a mild cough or low fever shows up. This is the opposite of SARS, where you had clear symptoms for a few days but were only contagious when sick.
22. TEDMED: If you have no symptoms, can you still infect other people?
Unfortunately, yes. And that makes it much more difficult to slow the spread.
23. TEDMED: How likely is it that scientists will develop a vaccine to prevent people from getting infected?
It is reasonably likely, but there are no guarantees that we will even have a vaccine. Failure is possible. For example, we’ve been searching for an HIV vaccine for 35 years and we still don’t have one. I’m optimistic that we will develop a vaccine for SARS-CoV2, but we will have to extensively test it for efficacy and safety – which takes a lot of people and time.
24. TEDMED: Assuming that a vaccine for coronavirus is possible and further assuming that it will be discovered fairly quickly, how long before we have a vaccine that we can start to inject into millions of people?
We will have vaccine “candidates” in a month or two. But because of the need for extensive testing to prove it protects and is safe, it will be at least a year before we have a vaccine we can inject into people that is approved by a major regulatory agency. In fact, 18 to 24 months is more likely by the time we scale it up to millions of doses, and that is optimistic.
25. TEDMED: Why will it take so long to develop a vaccine if this is an emergency?
It’s not necessarily vaccine discovery that takes so long, but vaccine testing. Once a “candidate” vaccine exists in the lab, a series of clinical trials are needed, first on animals and then on successively larger groups of people.
26. TEDMED: Have we made progress already?
The good news is that only weeks after the discovery and isolation of SARS-CoV2, which occurred in early January of 2020, vaccine development started immediately. Funding has been allocated by many governments and many companies and scientists around the world are working on it with great urgency.
27. TEDMED: Are scientists in these countries cooperating, or are they competing with each other?
A bit of both, and that is not a bad thing. But international cooperation has generally been good. That’s encouraging.
28. TEDMED: Can’t we develop a vaccine faster?
Unfortunately, there are no shortcuts. The human body’s immune system is complex and unpredictable. Viral mutations may occur. Children are different from adults. Women may respond differently than men. We need to be sure that any vaccine is 100% safe for everyone who gets it. To accomplish that, we need to test drugs and vaccines at various doses on a wide range of healthy human volunteers under carefully measured conditions.
29. TEDMED: How deadly is the new virus?
Most scientists believe that it kills 1% to 2% of all the people who become infected. The WHO currently reports a higher figure of more than 3%, but that estimate is likely to come down as they figure out how to count many unreported or mild cases. Mortality is clearly higher in older people and those with underlying conditions.
30. TEDMED: Is the average death rate the figure to focus on?
Not really. You can drown in an “average” of 3 inches of water. A better way to understand the risks are recognizing that it can be deadly for certain groups of people and much less so for other groups – with a wide range of outcomes.
31. TEDMED: So what are the numbers and checkpoints to focus on?
80% of the time it’s a mild disease, but in 20% of cases it becomes more severe, with the worst cases reporting high fever or shortness of breath. As a result some people require hospitalization, and some will need intensive care to survive through a few critical days when their lungs are extensively infected.
32. TEDMED: Which groups of people are most at danger here?
First of all, older people like me: I'm 71. The older you are, the higher your risk. Also at greater risk are people with underlying diseases such as diabetes, chronic obstructive lung disease and pulmonary disease or cardiovascular disease or immune deficiencies.
33. TEDMED: How much danger do these high-risk groups face?
Their mortality rate can be as high as 10% or even 15%. And, your risk increases when you have more health conditions. The scientific data about all of this is regularly updated on the web.
34. TEDMED: So your risk increases significantly if you have other conditions, such as diabetes. Why?
Because your immune system reacts poorly to any infectious virus, but particularly to this one.
35. TEDMED: It seems that generally speaking, children and young people are only mildly affected, if at all. Is that true?
This is what it looks like, but as for so many other issues on COVID-19, this requires confirmation.
36. TEDMED: If true, why would SARS-CoV2 affect older people much more, but not younger people and children?
We actually don’t know. It’s going to be a while before we figure it out.
37. TEDMED: Anything else unusual?
You can infect other people even if you are totally asymptomatic and feeling fine. That’s unusual, though it can also happen with HIV infection.
38. TEDMED: We often hear COVID-19 compared to the seasonal flu. What’s the right way to frame this comparison? For example, are the seasonal flu and coronavirus equally dangerous?
The seasonal flu typically infects up to 30 million people a year in the U.S., and fewer than 1/10th of 1% of the infected group will die – but that is still a big number. Worldwide, in an average year, a total of 300,000 people die from seasonal flu. But, on an average basis, the new coronavirus is 10-20 times more deadly, and in contrast to influenza, we cannot protect ourselves through vaccination.
39. TEDMED: Does the new virus spread as easily as the flu?
The new virus appears to spread as easily the flu.
40. TEDMED: Continuing with the comparison of flu and COVID-19, what about causes? Is the flu also caused by a virus?
Yes. Flu is caused by the influenza virus. But the influenza virus and coronavirus are very different. A flu shot doesn’t help you with the new coronavirus, but it greatly reduces your risk of flu. The common cold, for which there is no vaccine or cure, is often caused by another type of tiny virus called a rhinovirus, and occasionally another coronavirus.
41. TEDMED: How does the infection progress when the new coronavirus gets a foothold in your body?
It usually starts with a cough. Then a low fever. Then the low fever turns into a high fever and you get shortness of breath.
42. TEDMED: At what point is good medical care the difference between life and death?
It is usually when your fever is very high and your lungs are compromised so that you are short of breath or you need help to breathe.
43. TEDMED: How is the new virus different from a disease such as the measles, mumps or chicken pox?
SARS-CoV2 is currently far less infectious and dangerous but there is still a lot we don’t know about it. The other diseases are well understood.
44. TEDMED: If the new coronavirus is less dangerous than other viruses, why are many people so afraid of it?
Because new things that can kill us or cause us to be sick, make us very nervous. But accurate knowledge is the antidote to fear, so here in the U.S., I urge you to pay attention to CDC.gov. In other countries go your national health ministry or WHO websites.
45. TEDMED: How often should people check the CDC or WHO websites, or the website of their national health ministry?
We continuously update our knowledge as we learn more about the new virus, so these sites should be checked frequently.
46. TEDMED: Has mankind ever wiped out a virus completely?
Yes. Smallpox, which used to kill millions of people. And, we’re very close with polio thanks to the Gates Foundation and many governments around the world such as the U.S. Let’s not forget what a terrible plague that was in the world.
47. TEDMED: How does the new virus get to new places around the world?
By road, air and sea. Viruses travel by airplane nowadays. Some of the passengers may carry SARS-CoV2.
48. TEDMED: So, every international airport is a welcome mat for the new virus?
The reality is that SARS-CoV2 is already firmly present in most countries, including in the U.S., and far from any major international airport.
49. TEDMED: Since the epidemic began in China, do visitors from that country represent the biggest danger of importing coronavirus into the U.S.?
Since the new virus emerged in China in 2019, 20 million people have come into the U.S. from countries all over the world. The U.S. stopped most direct flights from China 4 weeks ago, but it did not prevent entry of the virus. Now cases of COVID-19 in China are often imported from other countries as the epidemic in China appears to be declining for the time being.