Hardly anyone in Switzerland knows as much about Long COVID as Milo Puhan. The epidemiologist at the University of Zurich regularly writes a report on the state of research for the Swiss Federal Office of Public Health (FOPH) and conducts research on the topic himself.
Milo, Omicron is spreading like wildfire across the country, with unprecedented case numbers. How great is the risk of getting Long COVID with this variant?
The high number of infections began in January with an initial peak at the end of January. However, the number of those who were infected that end up suffering from Long COVID can only be seen after three months. Even other countries where Omicron appeared a little earlier don’t have much of a head start to help us. Omicron has really spread brutally fast, so we don’t know enough about it yet.
Despite this, are the first trends starting to become evident?
There are only hypotheses so far. We could make the assumption that because it’s still the same virus, a similar number of long-term ailments are to be expected. Or we could assume that Long COVID is rarer in this case because of the milder symptoms. But these are all speculations. In Switzerland, we will be able to see the first indications from April/May. We are looking at this specifically in the studies carried out by Corona Immunitas.
You are investigating Long COVID yourself with a cohort study. What is that exactly?
A cohort is a group of test persons who are repeatedly interviewed and examined over a lengthy period of time. This enables the researcher to find out how their state of health changes over time and what factors influence it. With Long COVID, this type of study design is, of course, very interesting.
And what are you investigating in your Zurich cohort study?
The cohort consists of about 1,550 people who tested positive for coronavirus in February 2020 or later. We are monitoring who develops long-term symptoms, how long they last and how severe they are.
An initial result has been observed: after six months, 25 out of 100 people do not feel like they have fully recovered and have attributed this to the infection. Of those 25, 18 are mildly affected and four are moderately affected. Moderately affected means they can no longer work full-time, for example. Three are severely affected. In the case of those severely affected due to symptoms such as fatigue, shortness of breath or poor concentration, they are only able to participate in social and professional life to a very limited extent.
25 out of 100 patients do not feel like they have fully recovered six months after infection. (Image: Milo Puhan, University of Zurich)
After a further six months, nine out of the 25 affected individuals have fully recovered, 16 have not recovered or have only recovered partially. One person is still severely affected, three are still moderately affected. Thus, natural improvements do occur, but not for everyone and not to the same extent.
Can the complaints become chronic?
It’s still too early to say. Most of them improve, but we don’t know yet whether this is the case for everyone. It is also important that the correct diagnosis is made and that other possible causes of the complaints are ruled out.
16 out of 100 infected people still suffer from long-term symptoms a year after infection. (Image: Milo Puhan, University of Zurich)
Who is particularly at risk of being affected by long-term symptoms?
Pre-existing conditions certainly play a role here. The worse your health is before infection, the more vulnerable you are. However, it is not clear to what extent which pre-existing conditions have an influence. Asthma is a relatively consistent risk factor, but it is less clear for cardiovascular diseases. We are also taking a closer look at this in the cohort study.
Let’s talk about treatments: what progress has been made here?
A treatment that cures Long COVID currently doesn’t exist. What helps is being consciously aware of your own strength levels, what’s known as energy management or “Pacing”. This involves preventing setbacks as much as possible. Those affected also shouldn’t overexert themselves too quickly.
Then there are treatments for certain symptoms, such as shortness of breath, which we know of from other diseases, and empirical values can be seen here. We also know from other viral diseases that some people are limited for a relatively long time.
So we aren’t starting from scratch, but a great deal still needs to happen in terms of treatment. Various treatment studies are currently underway worldwide, but almost nothing has been published yet. We will hopefully be further along in this regard in six months’ time.
“A great deal still needs to happen in terms of treatment.”
How well are those affected cared for in Switzerland compared to abroad?
In Switzerland, the situation is similar to that of many other countries: there are a lot of local initiatives for those affected, but very few countries have a strategy in place for the overall healthcare system.
One country that does have an overall strategy is England, for example, where they have a good online service and an app where those affected can get information and self-management is encouraged. Family doctors are supported, and various specialist clinics are available. There is a clear plan behind this, which was launched back in 2020.
In Switzerland, everything is in place to take a similar approach. Information platforms such as Altea are available, plus dedicated family doctors – who could benefit from better support – and specialist clinics. However, they still operate relatively independently of each other; the various initiatives have not yet been brought together consistently. The care situation is currently being evaluated by the FOPH.
Wouldn’t the often-discussed registry be useful for this?
A registry can be structured in different ways and can serve different purposes. It is not simply a count of the total number of cases; that wouldn’t even be fully possible right now anyway. For health services research, a registry could be of use if there is minimal standardization to help characterize cases. After all, the type and severity of symptoms differ greatly among those with Long COVID. However, other tools such as cohort studies are more appropriate for determining the total number of cases.
What additional support would family doctors need? Would guidelines help, as we have seen them used in other countries?
A standardized assessment would certainly be helpful in order to objectify the complaints and to have a basis for triage: mild cases can be placed under the care of family doctors, people with organ-specific complications can be referred to specialists, and complex cases can be referred to interdisciplinary clinics.
As far as guidelines are concerned, it’s not like there’s nothing available at all; pulmonologists have actually already prepared some. We shouldn’t also forget that a hundred-page document that no one can consult on a day-to-day basis is only of limited use. The best, most practical guidelines should be able to fit on one page. In mid-March, a first compact assessment from the field of insurance medicine , developed by the University Hospital Basel and with our participation, has been presented. This recommendation will also be useful for family doctors.
This is a slightly shortened version of an interview (in German) first published on the University of Zurich websiteand in the Institute of Epidemiology, Biostatistics and Prevention’s ges.UND? blog.
Show
