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  • Thanks to Brilliant for supporting this episode of SciShow.

  • Go to Brilliant.org/SciShow to learn more.

  • [♪ INTRO]

  • Hello everyone! We think nothing looks different right now,

  • but if it does, it's because we've moved our studio to my home.

  • Because the state of Montana has told everybody to stay home for now.

  • We're doing that, because that is what we can do

  • to make this whole thing better.

  • I'll show you - I'll grab my phone right now.

  • And show you what it looks like from my angle.

  • This is where I sit and do my work!

  • And this is now the SciShow studio.

  • We want to keep you informed, so we are going to continue

  • bringing you SciShow News.

  • Regular SciShow is going to continue as well, and we'll have plenty

  • of videos about weird worms and cool stuff in outer space

  • to keep you occupied.

  • Now these days, a lot of people might be getting coughs or fevers

  • and stressing out because they're worried they have COVID-19 —

  • the disease a lot of people are just callingcorona

  • orthe coronavirus.”

  • And this is like totally understandable.

  • The main symptoms for COVID-19 can overlap with those

  • of common illnesses like the flu.

  • And, at least in the northern hemisphere, it's still cold and flu season

  • and the spring allergy season is beginning.

  • Meanwhile, it can be hard to even know if you have COVID-19.

  • Doctors want several kinds of tests to confirm.

  • It also can take multiple tests to know for sure

  • that you don't have it.

  • Even if you're tested and it comes back negative,

  • some reports suggest that in as many as 15-30% of cases,

  • that is a false negativemeaning you have the disease

  • but the test didn't detect it.

  • Which is why doctors may advise some people who get tested

  • to self-isolate, even if they test negative.

  • But knowing more about the symptoms of COVID-19

  • can give you some clues about what to do next

  • if you start feeling crummy.

  • First things first: If you think you might have the coronavirus

  • or want medical advice, you should talk to an actual doctor.

  • I am not that.

  • If you have acute symptoms, like trouble breathing,

  • pause all YouTube videos and call your doctor or the emergency room.

  • Still, the available research does tell us a lot

  • about what this disease generally looks like.

  • The three main symptoms everyone's talking about are fever,

  • dry cough, and difficulty breathing.

  • Which makes sense, because this coronavirus is mainly

  • a respiratory infection.

  • Two major review papersone in Travel Medicine and Infectious

  • Disease, one in the Journal of Medical Virologylooked at

  • symptoms across thousands of patients, mainly in China,

  • where much of our early info is coming from.

  • According to their analyses, close to 90% of adult patients

  • present with a fever, and about 58-72% have a cough.

  • Big range there, yeah, but this comes from doing statistical analysis

  • it means that we're 95% certain that the true number

  • is in between those two numbers.

  • Only the Travel Medicine authors looked at trouble breathing,

  • and they found that about 46% of patients had that symptom.

  • Now, the US Centers for Disease Control lists these as the top 3 symptoms.

  • But according to these reviews, fatigue and muscle aches

  • are right up there with difficulty breathing,

  • occurring in 29-43% of patients.

  • Kids seem to have much milder symptoms in general

  • for example, the review paper from the Travel Medicine group

  • found that only 44% had fever, and just 22% had a cough.

  • And there's some evidence that kids may actually have

  • different symptomslike more gastrointestinal issues, for example.

  • Also, it's important to remember that among both adults and kids,

  • many cases are presymptomaticthey already have the virus,

  • but do not yet have symptoms.

  • We still don't quite know what that means for how those people

  • spread the disease, but it is probably not good.

  • Likewise, we know that there is at least a small group of adults,

  • and probably kids, who are asymptomatic, meaning

  • they have no symptoms at all.

  • In fact, a mathematical analysis published in mid-March,

  • which looked at early cases in China and how COVID-19 then spread

  • around the world, estimated that up to 86% of cases

  • were mild enough to go undocumented.

  • That doesn't necessarily mean asymptomaticit's just not like

  • “I need to go to the doctorbad.

  • But the illness, of course, can still become very severe

  • especially when the fever, cough, and trouble breathing combo

  • turns into pneumonia, where the lungs become inflamed

  • and fill with fluid.

  • By the way, you may keep hearing that older patients

  • and those with preexisting conditions are more at risk,

  • and that is true. But even younger, healthier patients

  • can develop pneumonia, which ain't nice.

  • The two papers found that in 15-33% of confirmed COVID-19 cases,

  • the pneumonia can progress to acute respiratory distress syndrome,

  • where fluid buildup leads to a severe shortness of breath

  • that can be fatal.

  • That's why having enough ventilators, which help people breathe,

  • is so important.

  • None of these symptoms, of course, are surprising;

  • there's a good chance you've heard all of this before.

  • But there are the rarer symptoms, too.

  • The paper in Travel and Infectious Disease didn't specify numbers

  • for these, but the other group found that about 11% of patients

  • had a sore throat, 8% had a headache, and 6% had diarrhea.

  • This is where you start to see how research on something

  • as new as this coronavirus can be tricky.

  • Both of the review papers we've been talking about

  • only looked at studies released through the end of February.

  • But some of the more recent research seems to disagree

  • about how common digestive symptoms are.

  • In a study that followed patients through March 18,

  • researchers in China found that of 204 hospitalized patients,

  • half had digestive symptomsloss of appetite, diarrhea, vomiting,

  • or stomach pain.

  • And even if you don't count loss of appetite as a digestive symptom,

  • 19% of the patients still had GI issues.

  • The researchers note that this study has some limitations

  • for example, it doesn't have a huge sample size.

  • But it's a sign that digestive symptoms may be more common

  • than we thought based on earlier studies.

  • Again, all of the symptoms of COVID-19 can be caused by

  • plenty of other infections, from flu to a stomach virus

  • to the common cold.

  • And in many places that don't have big outbreaks,

  • it is still much more likely for people experiencing symptoms

  • to be sick with something other than COVID-19.

  • Even in New York State, which has one of the largest outbreaks

  • in the world as of this recording, about 2/3 of tests

  • were coming back negative as recently as last Sunday.

  • It's also worth noting that the coronavirus doesn't usually

  • come with itchy, watery eyes, and a runny nose or sneezing are rare.

  • So those symptomsespecially without a fever

  • might point to allergies or a cold instead.

  • Then again, there's no reason someone couldn't have allergies

  • or a cold and also have coronavirus.

  • So if you've got a runny nose, that doesn't mean that you can

  • run out and celebrate that you don't have COVID.

  • And there is one weird symptom that might be a sign it's COVID-19:

  • it's losing your sense of smell.

  • As of when we're filming this, which is March 31st,

  • this is still very much an emerging possibility,

  • not a for sure thing yet.

  • But anecdotal reports started coming out a few weeks ago,

  • and once people were paying attention to it,

  • researchers started finding more evidence of it as a symptom.

  • An initial analysis, published on March 26 by researchers in Germany,

  • cited reports that up to two thirds of patients

  • had lost their sense of smell.

  • And a group of British researchers report that in South Korea,

  • 30% of otherwise mild cases had a loss of smell as their main symptom.

  • The World Health Organization, or WHO, says it's looking into this link,

  • but that there's not enough evidence yet to say

  • the connection is really there.

  • Because even this isn't a for sure sign of coronavirus

  • other respiratory infections can also affect your sense of smell.

  • What's more, there's the possibility of this bias where people

  • start reporting symptoms that they've heard about

  • so the media or social media picks up on the smell thing,

  • and then more people start to notice it and report it.

  • Still, researchers are starting to recommend that people

  • who lose their sense of smell should be told to self-isolate

  • for a week or two.

  • They think it might help reduce the number of mild cases

  • walking around and spreading the disease.

  • All in all, it's tricky to diagnose people without

  • actually testing them for COVID-19.

  • Because even with testing capability ramping up in many countries,

  • there are still limitationslike having enough people

  • to administer and process those tests.

  • That's why the WHO has two main sets of recommendations.

  • The first is for people who have severe symptoms,

  • like a high fever, bad cough, or difficulty breathing.

  • In those cases, those people should seek medical attention.

  • The other recommendations are for people who are otherwise healthy

  • but have mild symptoms that could be COVID-19.

  • In those cases, the WHO recommends people self-isolate

  • and contact their doctor or a COVID-19 hotline

  • for advice about getting tested.

  • Doctors also say you can take medicines like acetaminophen

  • or ibuprofen to help with symptoms.

  • Those aren't going to help the course of the disease,

  • but they will help you feel better temporarily.

  • There was news that went viral recently about the French Ministry

  • of Health saying ibuprofen or similar medications

  • could make the illness worse, but that was speculation

  • based on an unproven theory about how infections work.

  • It was speculation published in a reputable journal,

  • but in science we actually need evidence, and so far there isn't any.

  • Some people might have issues with ibuprofen, and if that's you,

  • you probably already know to avoid it.

  • And none of that is specific to COVID-19.

  • So far, the WHO hasn't recommended against taking ibuprofen.

  • They also have some recommendations on how. to care

  • for someone with this disease, if hospitalization isn't an option.

  • There's a link to that in the video description.

  • It includes vigilant handwashing and trying to maintain

  • at least a one-meter distance between the patient

  • and the other members of the household.

  • This is a scary time, but if you have seasonal allergies,

  • you are probably pretty familiar with how they affect you

  • so your old reliable allergy symptoms are nothing to panic over.

  • If you feel like your symptoms are more unusual,

  • stay in and call your doctor for advice.

  • This is a good opportunity to recognize that we often

  • sort of colloquially say like this particular disease starts

  • with this symptom, then it progresses this way -

  • but this is different for different people.

  • So there's no one symptom or one disease progression

  • that tells you for sure that you have COVID-19.

  • Especially because many people have it and do not have symptoms yet,

  • or may not ever have symptoms.

  • So limiting contact with others, whether we are symptomatic or not,

  • is still the best thing we can do for our society

  • and for the people on the front lines of this fight.

  • But researchers are working hard to change that.

  • We'll be keeping an eye out, and you can expect upcoming SciShow News

  • episodes to bring you more info in the coming weeks.

  • Until then, stay safe, and thanks for watching.

  • If you, like me, might need things to take your mind off current events,

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  • Right now, they're offering the first 200 viewers to sign up

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  • And by checking them out, you're also supporting SciShowso thanks.

  • [♪ OUTRO]

Thanks to Brilliant for supporting this episode of SciShow.

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