Breakthrough: Covid’s Long, Scary Tail

in Australia's Northern Territory. When she was in high school in suburban Melbourne, Alex looked into becoming a midwife, and at a career spare, she watched instructors explain the childbirth process. It got to a point during a simulation of an obstetric patient that they said, all right, now this is where we stop. We'll have to go and get the doctor. You'd have to go and get the obstetrician. And I said, how what what about that? What can I do that?

And they said, oh, you'd have to go to medical school. So I went to medical school. Last forward to early Alex's entering her second year working as a fully qualified doctor when she hears news of a novel coronavirus emerging in China. The first place I heard about it when it was when I was in Argentina in January and the person that I was backpacking with he said, oh, have you heard about this coronavirus? And from from a science background, I just thought, what are you talking about?

What coronavirus? They're they're a family of viruses, which particular one are you talking about? And then it just snowballed from there. Patients are already coming to the Metropolitan Hospital with the disease by the time Alex gets back to Melbourne. Because you'd see young patients come in who were COVID positive and you can't help but think this could be me, or this could be a friend of mine, or this could be a family member. So it was it was

a scary time to work. A few months later, cases are escalating and Alex is working on a general medical award when she starts feeling off. I was doing run of seven nights in a row and I was on my seventh night and it was about two am and I was walking around the wards thinking, oh, I'm a

bit short of breath. I shouldn't be. I my heart rate didn't drop below a hundred so I thought, maybe something's up here, and I've been treating a lot of positive patients throughout the week um and towards the end of the shift, I got really sore all over my body. I couldn't really ignore those symptoms, so I went straight away to go and get tested. The test comes back positive, so Alex goes to a hotel. Australia uses hotels as quarantine centers to try to prevent the coronavirus spreading in

the community. About a week into her infection, Alex gets a running nose and cough, and then a few days later she completely loses her sense of smell and taste. I remember having a green curry delivered to my hotel quarantine, and I filmed myself putting my face right up against it, and I couldn't not smell a single thing. I could taste that it was hot, and I could taste that it had some texture, but beyond that, I could not taste a single thing. And I also put my head

in a coffee bag and that smelt nothing. It's a lot of weird videos that came out of COVID quarantine. Alex is eventually clear to leave quarantine, but her distorted sense of smell and taste persist. More than a year later, She's still suffering the consequences of catching COVID nineteen. It's unclear how long her symptoms will last, but Alex isn't alone and being plagued by the effects of the coronavirus long past her recovery from the initial stages of the illness.

There haven't been any studies published yet estimating the global prevalence of patients like Alex, but at least one inten COVID patients have symptoms six months later, so the number of these so called long haulers could run well into the millions, if not tens of millions, well t wide. Once Alex loses her sense of smell, she knows exactly who to contact. It's been a very, very fruitful friendship.

And then, obviously, when I got the very sad news that Alex was diagnosed with COVID, she Facebook message me. I think the message said a bit of fun news, I have COVID, you said it'll be right. That's Dr lea Bencham. She's a neuroscientist who studies smell. Alex and Lee are best friends. They've known each other for more than a decade inside, I was panicking um and then I asked her if she could smell, and she said, well,

I can't taste. And then I actually sent her an olfactory kit in the in the hotel because I worked with those a lot, and I quantified her sense of smell and she did or abysmally. I spoke with Leah and Alex at the same time in a studio at the University of Melbourne where they both studied. Alex and returned for a short visit. This is the story of two friends, two doctors in fact, who were trying to understand one of the most common signs of COVID night team.

The loss of the sense of smell or old faction, affects almost one and every two people who get the pandemic disease. Usually it resolves within a week or two. For some, like Alex, smell and taste distortions persist, leaving an invisible illness that leads to a profound disruption to their daily life that affects their mood and relationships. But scientists are learning that its significance doesn't end there. This is also a story about living with a mysterious condition

that may have a lasting impact on health. Evidence is emerging that COVID survivors like Alex could face even worse neurological issues later in life. I'm Jason Galas, Senior Editor and Chief by a security correspondent at Bloomberg News. From the Prognosis podcast. This is breakthrough Lea and Alex meant

just before beginning their first year at university. We were in a car on the way to an orientation camp and we met in the backseat and may have shared a bag of coon and we have been really good friends ever since. First friends. Goon listeners is an australianism that refers to wine that's sold in a plastic bag

inside a cardboard box. After that, Lea and Alex stay close throughout undergrad and then Alex popped off to do postgraduate medicine and I popped off to do postgraduate biomedical science. We lived together during our postgraduate years. Odship is just a tipping balance between beer and science. Really. Leahel works at the University of Melbourne's floor Re Institute of Neuroscience and Mental Health. It's one of the world's largest brain

research centers. After Leah gets the message about Alex's positive COVID tests. She says she wants to see how badly Alex has lost a sense of smell. Scientists have a standardized way of testing one's ability to detect sense and odors. It's a type of scratch and sniff test. It requires users to smell odorant molecules from separate panels in a series of booklets and then indicate which of four multiple choice answers best characterizes each smell. Users get a grad

out of forty. Alex failed spectacularly. A nosmere and dyscousia are terms doctors used to describe a loss or impaired sense of smell and taste. People sometimes lose these senses in the early stages of Parkinson's and Alzheimer's diseases, but short term losses occur more frequently with upper respiratory tract infections. COVID, though, has added another dimension. Leah says, we don't really know why the coronavirus results in longer term effects on smell

and taste. Initially it was thought to be because of inflammation, like the block nose you gave with a cold. I think it was a symptom that was ignored because It was very much thought of you've got a block nose. Of course you've lost your sense of smell. But then more and more data was coming out about people who had no other symptoms, that only symptom was a loss of spell. They had hyperson out, they didn't even have a running nose, and we started looking at that data

and thinking there was there was more to it. There was also the belief that any lost sense of smell would be recovered within a month. It turns out that was based more on optimism than evidence. A study in the Journal of Internal Medicine and January found almost a quarter of sufferers hadn't recovered that sense of smell after two months, and by six months five were still living

with the derangement. And we have no idea why. What we do know is that the coronavirus targets are protein on the surface of cells that lie the airways from the nose to the furthest reaches of the lungs inside the nasal cavity. The cells the coronavirus targets are right alongside the nerves that tell the brain what odors are being detected. Leah says it makes the nose a particularly interesting part of the body to study. This area of

the nose is fascinating. It's one of the reasons I got into olfactory science in that there are brain cells that project down into that region. So it's actually an area of your body where your central nervous system is exposed to the environment, and that makes that region particularly vulnerable. These nerve cells protrude the bone in the skull that separates the nasal cavity from the brain. The bone is

perforated like Swiss cheese. Some scientists contend that the loss of smell and COVID patients results from the virus infecting the nose and causing inflammation there that subsequently damages these olfactory neurons or nerve cells, but that doesn't really hold up when you're talking about a year down the track, there shouldn't be any more of this acute inflammation. Leah

has some other theories. So one is that because of these neurons that project into the nose directly from the brain, the virus is actually able to get into those neurons and it's able to get into your brain, therefore causing damage because you have viral particles in your brain. That's one hypothesis. The other is that it's not able to get into your brain, but it can get close enough to those neurons that it can trigger an inflammatory response.

Lea says that from there, the inflammatory response can cause a reaction that still harms the brain. Some scientists have published research showing that the virus can get into the brain. Others have published research showing that it can't. Intriguingly, scientists at the past Institute in Paris describe finding the sanskvt virus in the cells that line the roof of the nasal cavity in a half a dozen patients who lost

their sense of smell for months. I spoke with Dr p M Marie Leto, neuroscientists who led the study, which was published in Science Translational Medicine back in June, and one of our surprise came when we find in fact that for all of them, we could find the presence of the viruses in the sensory organs, explaining why those people were impaired in recovering this sense, which was very surprising for us because several publications at least report that

old factory censory neurons located in the old factory organ where those centory neurons were not expressing the receptor for the for the various is therefore they should not be infected. The French scientists found protein made by the coronavirus as well as antibodies against it, but they weren't able to demonstrate that TASKOV two can replicate in the sensory organ It's something P. M. Marie is still exploring because if they're still viable or infectious virus particles there, that could

have consequent answers for transmission. If with dealing with replicative viruses in the Austrila, those people might be contagious by by just breathing, they will be spreading the viruses around them. So it's it's a it's a question that we are now following by recruiting more and more people brooding chronicling their old factions in order to address this question. So this is under investigation. Lea says there's no agreement among scientists about whether the virus is able to persist in

the body, much less the nostrils. I think it's a good theory, though. Lea says it fits with another theory that scientists have mentioned several times in our earlier episodes that involves the consequences of immunization against the coronavirus. There's anecdotal evidence. None of this is published because it's very hard to quantify, but people have come out and said that after they've been vaccinated, they feel the symptoms of

long covid getting better. They are not necessarily fully recovering, and some people notice nothing. Some people feel like they're

a bit worse. But there are a large number of peabloo say I can actually smell a little bit better two weeks after the vaccinated, and that really lends itself to this reservoir hypothesis, because maybe your immune system wasn't able to clear that last little bit virus that's sitting in your ethelial cells, but a vaccine, which is a much sort of more direct approach at boosting the immune system,

was able to clear it. So I think it's definitely got legs, but I think it's very early on um and we need many more studies to replicate it for us to say this is actually what's happening. There's still a lot of questions around how long COVID causes us to lose some of our senses. While scientists are accumulating evidence about the virus and its long term impacts on biological processes such as aging. There's been a lot of research published documenting the ways in which the brain is

damaged following a saskvy to infection. There's inflammation, blood clots, and hemorrhages, not to mention respiratory failure that can cut off oxygen supply. But another aspect of COVID has surprise researchers in recent months, the loss of brain tissue. That's right, COVID is associated with brain shrinkage. A study in June from the University of Oxford, released a head of peer review and publication, found gray amount of deficits were more likely in patients who had had COVID than those who

were never infected with the coronavirus. It was a unique study that used medical records and brain scans from patients taken before the pandemic. The researchers then invited hundreds of these patients back for another round of m r I brain imaging. There were marked differences between those who have been infected with COVID nineteen and those who had not in terms of gray manner, which is made up of the seal bodies of neurons that process information in the brain.

More interesting still, there was a loss of brain volume even in COVID patients not sick enough to require hospitalization. The findings haven't been published in a scientific journal, but Leah says the study offers important insights into what might be going on inside the brains of long haulers. This is probably one of the most impressive papers that I've ever read. It is, and what they've shown is that quite scarily, actually there's there's a loss of gray matter

in a number of regions of the brain. Most of them are related to olfactory and gustatory pathways, which explains why potentially many people are not recovering their sen's a smell or even if they have recovered it, it's not fully recovered um because you've actually you've you've actually lost brain tissue in those regions. And there's also some indications that the limbic region might be involved. Lea says that the part of the sing that COVID appears to shrink

affects mood regulation. This might explain why anxiety, depression, and brain fog are common symptoms of long COVID. We're seeing huge numbers of anxiety above and beyond what we would have expected in long COVID. But it's not just that COVID can affect mood. Scientists predict that it will also be associated with longer term neurological problems like dementia. Lea says inflammation caused by COVID essentially primes the brain for

further injury down the road. And once your brain is primed, if you get another hit later in life, like another severe virus, viral infection that gets into your brain, or you're exposed to a toxin, you're closer to the edge because your brain is primed and it's ready to overfire. And when it does that and the new inflammation takes hold,

it's going to kill cells faster. So we're talking here about not COVID causing any of these diseases, but it's just an increased risk factor that we need to be aware of that a very large population of the world has now had. Leah says that because COVID affects so many different parts of the brain and its functions like memory, it could predispose degenerative diseases such as Alzheimer's. She's particularly concerned about what this could mean for Parkinson's disease too.

It's a disorder of the central nervous system that affects movement. About ten million people worldwide have the condition, and the number is growing, in part because age is a major risk factor and humans are living longer. So at the moment we're actually living through a Parkinson's pandemic. It's doubled in the last twenty years our incidents, and it's set to double again, and that's after we correct for the

aging population. Now that we've just added covid in, there's a chance that we have just even the slightest shift of people more likely to get Parkinson's that could push us into numbers that we can't cope with. Parkinson's is a very long disease. It's a very expensive disease. We don't have disease modifying drugs or we can do is help you symptomatically for a few years until that stops working. It's really scary and we need to be really vigilant.

There was a surge in cases of Parkinson's disease in the decades following the nineteen eighteen Spanish influenza pandemic. Epidemiologists determined that Spanish flu survivors had a two to three times higher risk of developing Parkinson's now term viral parkinson Is UM compared with those who didn't get the deadly flu strain. If a similar effect were to occur in the wake of COVID, Leah says EQUOD cripple health systems.

There's warning bells, and where we're trying to listen to those warning bells, I think because we don't want to be caught off guard and our community itself. Would you know, most people who are diagnosed with Parkinson's are still of working age. We can't lose that workforce loss, so there's an economic side to it as well. We need to be really prepared and the only way we're going to

do that is to keep studying it and preparing as best. Weekend, as we sit in the studio in Melbourne, Lea in our sitting side by side, Alex knows that when Lea talks about the future risks around long COVID, she's talking about pretty frightening things that she could face one day. It's a bit hard to listen to. I have known Lea for a very long time and She's been very frank and honest with me about the research and the

places that this could go. That's why I think research likely is is so amazing that we can be putting money into finding the exact mechanisms behind how this happens. Why why does one person get more affected than another person? Are the things that they could have changed in their life or their lifestyle factors that could have been different that makes them less or more susceptible to a disease and to long term COVID as well. Some of alex the smell has come back, but she says it's not

the same. It's quite sad not being able to smell and taste the things that you have loved before. I was previously quite into my beer and craft beer. I used to brew beer at home, and I now don't really like dark beer, which is it's maybe trivial to some people, but it's really sad to me. I don't like particular foods that I used to make. I make dumplings quite a lot with friends, and I can't eat them now because it tastes like COVID. I don't know

how to describe what that taste is. It doesn't taste like anything that I've tasted pre COVID, but it reminds me of particular time in my life, and it doesn't taste good. Alex says she's fortunate her loss of smell hasn't depressed her. I think I've had a lot of support from my friends and family about being able to talk about the ways that it's affected me. It has certainly removed a lot of the pleasure in tasting food, and I don't get a lot out of fine dining

experiences now that other people might find. But I'm also part of a Facebook community of people who have lost their smell and taste, and there are some really tragic stories of people not being able to smell their kids anymore and how much that upsets them, and how they're now six eighteen months down the truck from their COVID diagnosis and they still don't get any enjoyment from tasting food.

She's clearly concerned about the fact that long COVID might continue to affect her, and that the full extent of her infection might not be revealed for decades. I think the respiratory symptoms may play out in the next ten to twenty years. I don't have a scientific base for

that prediction. I think that as a fit, healthy person that can still run five case if I need to, I don't think my lungs have been that horribly scarred, but I would not rule out getting some kind of interstitial lung disease in my thirties or forties or fifties, which is really scary. Interstitial lung disease is a pretty horrible condition that causes the development of fibratic scar tissue.

Eventually the lungs become brittle and resemble honeycomb. In the US, there's already been a big jump in double lung transplants and COVID survivors because of this. I don't want to die prematurely. I don't want to have a chronic disease that leaves me on oxygen at home. That's not the future that I envisaged for myself. But I also know that I'm very lucky in that I don't have a lot of other symptoms of long COVID. So I don't have the memory fog, I don't have the anxiety or depression.

I don't have the crippling fatigue, I don't have the motor symptoms yet, So I also feel quite guilty when I talk about losing my sense of smell and taste, because I know that so many other people, including my patients that I treated at the time, have it so much worse. Alex says, hairy experience of COVID and it's alarming consequences will at least help it be a been a family doctor. I think it's it's scary to know

that I might have a shortened lifespan. Potentially, I might have Alzheimer's earlier, I might develop Parkinson's, I might end up one oxygen. But I can't change any of these things. All I can do is as a GP in the future, I can look after patients who have had COVID. I can support them through that and just impress upon other people the seriousness of COVID and the importance of getting vaccinated.

The legacy of COVID is still emerging, and we won't know the full extent of its economic and social impacts or the repercussions on health for decades. But the more we learn about the coronavirus and after it thanks, the more it's showing to be an infection. We should do whatever we can to avoid h that's it for this episode of Prognosis Breakthrough. On the next episode, my colleague John Lawman goes into a Boston hospital to learn how

the pandemic has reshaped health services. COVID is leaving indelible marks not just on patience, but also on those delivering medical care. I'm hearing more more clinicians now who say I cried all the way to work. I didn't want to get up this morning. I love my job, I usually love my job. I don't want to go to work. It's too hard, it's too much. This episode of Prognosis for Through was written and reported by me Jason gale Jo for Forehes is our senior producer. Cole Kevin Robinson Jr.

Is our associate producer. Special thanks to Chris hatss A. Theme music was composed and performed by Hannes Brown. Rick Shin is our editor. Francesco Levi is the head of Bloomberg Podcasts. Be sure to subscribe if you haven't already, and if you liked this episode, please leave us a review. It helps others to find out about the show. Thanks for listening.