German virologist Christian Drosten
Published by marco on
Professor Christian Drosten is a virologist working at the Charité University Hospital in Berlin. Since the beginning of March, he’s been doing an informative podcast in German called Coronavirus-Update. I’ve found him to be highly informative and factual in a world filled with propaganda, conspiracy theory and shoddy science.
The following interview with Drosten was one I found in English, which he also speaks fluently. I thought the 30 minutes, in particular, were very enlightening (citations below).
At about the 1:05:00 mark, Drosten discusses excess mortality and puts a wooden stake through the theory that COVID-19 is a slightly more contagious and therefore only slightly more deadly flu.
“You can look at the excess mortality. In Germany 850,000 people die per year. There is something like an average mortality per unit of time. You can compare the average mortality against the mortality for December-March, which is the flu season. This yields the influenza-related excess mortality. This can be between 8000 and 30,000 per year, in Germany. [presumably depending on whether the influenza vaccination was properly targeted. –ed.]
“For the countries that have already reported their mortality figures for this year—and they are reporting for March/April of this year—[…] what you see is an increase of mortality in the population that hasn’t been seen before—and this is with a lockdown in place.
“This is from countries with an efficient reporting system and with a national health-care system that enacted an early and efficient lockdown. Belgium, Netherlands … even UK. For Sweden, we don’t have numbers yet. But for many, we do have numbers and it’s out of any question that, in spite of the lockdown, the excess fatality rate in this period of time is so much higher than previously seen that this whole discussion about whether the virus is similar to influenza in terms of fatality, this is concluded. We don’t have to discuss this anymore.
“All we have to do is take care that we don’t see the true excess mortality that this virus could cause, without a lockdown. And I’m afraid we may see such figures in poorer countries of the global south. I can’t predict what the different age profiles in these countries will cause. Poor African countries have much fewer old people in their population. They have many more general immuno-modulatory diseases like warm infections that we don’t have, so all of this may even be beneficial—and we may not see the horrifying number, but I can’t predict. Nobody can predict.”
And, as Angela Richter points out, “There is a lot of underlying immunity [to influenza] in the population due to vaccination and also due to prior infection,” a factor that doesn’t affect COVID-19 in the least, in this, its first year. Drosten concurred that “It doesn’t look like the common cold is delivering a similar effect, or at least not a strong one.”
They then discussed a topic that I only rarely hear discussed: what are the outcomes in between a full recovery and death? Very few people are discussing the likelihood of prolonged reduced lung capacity or possibly chronic, life-long malady associated with having had the disease. It’s clear that there are those who get mild symptoms. It’s clear that some get hit by a proverbial truck and will take a long time to recover (e.g. from intubation, from weight loss, from having lain prone for weeks on a ventilator, etc.).
Richter asks about the reports of “organ damage”, for which Drosten has a more reassuring reply. He talks about how some of the receptors in blood vessels are the same as those that attach to COVID-19 in the lungs and that makes it possible for the virus to travel to other organs (Cytokine storms, strokes, blood clots). It can attack the heart and the kidneys, with “coagulation sources”. The primary attack vector is the lungs, but there are rare cases where other organs are attacked (but very rare … 30 cases per country, e.g. Germany). “In adults, it’s not the prime manifestation”. These cases are only just being examined because they’re quite rare.
Learning from other pandemics
The next podcast is in German and is from Drosten’s bi-weekly show.
The first fifteen minutes is the most interesting for the current crisis. After that, he discusses the flus of 2009 and 2014 and the inapplicability of the measures or medicines to COVID-19.
I picked up the following take-aways, which I have translated faithfully but loosely.
There is no chance that you’ll catch the virus from meat. It’s stored for a long time, there are lots of other organisms on meat that attack the virus, and you’re almost certainly going to cook it. The connection to meat is that the people packing the meat work in very close quarters and in very cold temperatures, which seems to lead to a higher contagiousness for COVID-19.
Excess Mortality Redux
As previously mentioned, there are new studies that show that the excess mortality for many European countries is clear and, in some places, much, much higher. In one region in Italy, a new study shows 150 dead in just one quarter, so it’s already at 15x the normal rate. 10 per 1000 usually die in the region. Maximum 21. In March of 2020, 155 died. At least 85 of these had tested positive for COVID-19.
There is no reason to believe that this excess mortality is due to a worse health-care system (it’s one of the richer regions in Italy) or that there were older people there (it wasn’t particularly excessive, no more so than other European countries). This was a region where they were caught by surprise, but were actually in quite a severe lockdown for most of March.
So there was clear excess mortality even with a lockdown and the lockdown started only just as the exponential curve was starting. If there had been no lockdown, the region would have experienced the full brunt of the exponential curve, which would have pushed excess mortality (and other damage) much, much higher than 15x normal. This is quite sobering.
Outbreak in Kano, Nigeria
Recently, in some countries in the global south, there are reports of, for example, Kano in Nigeria. It’s clear that they have a massive outbreak and it will most likely proceed there naturally because lockdowns are more difficult to enforce there. Nigeria’s actually doing well, all things considered. But they, too, have one study where 21 doctors in just one hospital tested positive for the virus (they actively had it). Even some of the lab personnel had it, even though they have no contact with patients.
Even anecdotally, a questionnaire of 100 family members and friends of one of the study authors yielded that nearly every member had had symptoms with loss of sense of smell and taste for a few days. It’s unclear what this will mean for death in these countries. Can they flatten the curve? Or will they look like New York City? Or something in between?
NYC as first-world warning
What is also unclear for those who don’t read/listen to English news is what happened in New York City. It tore through there like a firestorm. Germans seem to be largely unaware of what can happen if proper measures are not followed and the disease really spreads its wings. They believe that they, as a first-world country, can protect themselves no matter what. Drosten says that this leads to a much higher rate of denialism in both the population and media, both of which are highly counterproductive and could lead to more suffering if and when a second wave appears.
As for the Swine Flu, we underestimated it. About the same number of people died of it as died of the standard flu. Only 20% of those who died were over 65 years old, which is very different than the standard flu. There follows a long discussion of the various flus that continue to circulate and their relative dangers. There is unfortunately not very much similar between the Swine Flu and COVID-19, so we learn nothing from it that will help us in the short-term.
Finding the Red Marble
The most recent podcast from Friday discusses the importance of not only contact-tracing, but “controlling the red marble” i.e. stopping so-called super-spreaders.
I thought the most important take-aways from this most recent podcast were the following:
- Proximity × time = infection rate
- Being inside is vastly more risky than being outside. One reliable study from Japan shows you’re 19x as likely to be infected indoors as outdoors.
- That would indicate that we can take advantage of the summer by moving our public lives outside. Cafés could be encouraged to maybe not have the same distance requirements outside as inside.
- Masks should help inside, but not over longer stretches of time
- Being outside is very low-risk, as long as proximity rules are respected (e.g. garden party with a few people or while hiking)
- A lockdown is an admission that we don’t know where the disease might be; we use it to minimize number of simultaneous outbreaks
- Reliable tracing is the only way to avoid using lockdowns
- Tracing is made more difficult by probabilities. There is a decent chance that everything looks OK for a long time until a super-spreader activates a new outbreak. The is the “red marble” of which Drosten speaks. In his analogy, when you reach into a bag of 100 marbles, you might get the one red marble on your first try; or, it might take a dozen tries over months before you get the red marble. An outbreak awaits the whole time.
- The best way forward without full lockdowns is finding, tracing, and stifling clusters. This means quarantining anyone who can be associated with a positive result without testing first (as we do now). Instead, we should isolate, then test. Guilty until proven innocent works better for reigning in super-spreaders.
- The asymptomatic, potentially infectious phase is shorter than we at first thought—it is sufficient to wait only one week instead of the heretofore recommended two to catch all but the most extreme cases.
- E.g. If a teacher gets sick, then all students associated with that teacher should stay home for a week. Whoever doesn’t have the disease after a week can go back to school. For those who do, apply recursive tracing. The (new) good news is that you don’t need to keep people in lockdown for 2 weeks and you almost certainly don’t have to close the whole institution (unless perhaps there are multiple, simultaneous outbreaks).
In the podcast, Drosten recommends the science-writing of Kai Kupferschmidt, a German who happens to write in English for the magazine Science. His most recently articles are in fact quite informative. The article Study claiming new coronavirus can be transmitted by people without symptoms was flawed by Kai Kupferschmidt (Science) examines the by-now notorious pre-print that led many to believe that asymptomatic people were shedding viruses.
It turns out that the lady at the center of the study was not asymptomatic, but just had milder symptoms that were not as obvious to colleagues, who’d all reported that she “didn’t seem sick”. When they finally interviewed the woman herself, she readily reported that she’d felt tired and under-the-weather during her entire stay in Germany. A rush to publication and sloppiness in language led to a report that ran around the world and likely still serves as the kernel of people’s belief that COVID-19 can be spread by asymptomatic people.
“The German cluster does reveal another interesting aspect about the new virus, Drosten says. So far most attention has gone to patients who get seriously ill, but all four cases in Germany had a very mild infection. That may be true for many more patients, Drosten says, which may help the virus spread. “There is increasingly the sense that patients may just experience mild cold symptoms, while already shedding the virus,” he says. “Those are not symptoms that lead people to stay at home.””
Stopping Clusters and Super-Spreaders
The article Why do some COVID-19 patients infect many others, whereas most don’t spread the virus at all? by Kai Kupferschmidt (Science) discusses the k-value (dispersion factor) versus the R-value (reproduction number). A lower dispersion number means a higher number of people with an R of zero with a low number of people with a very high R (super-spreaders).
“Sometimes a single person infects dozens of people, whereas other clusters unfold across several generations of spread, in multiple venues.
“Other infectious diseases also spread in clusters, and with close to 5 million reported COVID-19 cases worldwide, some big outbreaks were to be expected. But SARS-CoV-2, like two of its cousins, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), seems especially prone to attacking groups of tightly connected people while sparing others. It’s an encouraging finding, scientists say, because it suggests that restricting gatherings where superspreading is likely to occur will have a major impact on transmission, and that other restrictions—on outdoor activity, for example—might be eased. (Emphasis added.)”
It also means that increased mobility between countries—even those with unequal R-values—will be less risky than previously thought.
“If k is really 0.1, then most chains of infection die out by themselves and SARS-CoV-2 needs to be introduced undetected into a new country at least four times to have an even chance of establishing itself, Kucharski says.”
The article also discusses how the virus seems to be spread—i.e. trying to explain why the k-value would be lower.
“Most published large transmission clusters “seem to implicate aerosol transmission,” Fraser says.
“Individual patients’ characteristics play a role as well. Some people shed far more virus, and for a longer period of time, than others, perhaps because of differences in their immune system or the distribution of virus receptors in their body. A 2019 study of healthy people showed some breathe out many more particles than others when they talk.”
The interviewed scientists also emphasize that the outdoors is really our friend for limiting COVID-19 outbreaks. While the heat of the coming summer is unlikely to affect the virus itself, the fact that people are more likely to be outside will limit transmission vectors and help to kill it off—at least for now.
“The factor scientists are closest to understanding is where COVID-19 clusters are likely to occur. “Clearly there is a much higher risk in enclosed spaces than outside,” Althaus says.”
This means, though, that white-collar workers (e.g. software developers, like myself), should stay in home office in order to reduce needless risk incurred by being inside. Drosten even recommends that schools start holding classes outside, wherever possible.
“If public health workers knew where clusters are likely to happen, they could try to prevent them and avoid shutting down broad swaths of society, Kucharski says. “Shutdowns are an incredibly blunt tool,” he says. “You’re basically saying: We don’t know enough about where transmission is happening to be able to target it, so we’re just going to target all of it.””
“Fraser […] says: “Understanding these processes is going to improve infection control, and that’s going to improve all of our lives.””
All of this information is encouraging in that it’s showing the way for shaping a society that knows how to live with a disease like COVID-19 while keeping mortality low, offering acceptable social activities, and being economically viable. We still don’t have a good answer for foreign vacations or foreign travel, but at least we might know how to hang out with friends without risking an outbreak. That should tide us over until the fall and winter, when “being outside” becomes much more difficult. This is us now…perhaps only for a few years, perhaps forever.