“It took me a year to get diagnosed with long Covid. Doctors acknowledged that I had long Covid, but they did not want to write it down. They put it down to anxiety or all sorts of vague things.”

Ryan was infected with Covid at the beginning of 2022. As symptoms lingered on after a few weeks, he went to his family doctor. The GP suspected long Covid but had to rule out other conditions first. After seeing numerous specialists, he finally got an appointment with one of the rare long Covid specialists in France. “Ultimately, my GP didn’t really have much say in all this. He received reports from specialists. He could simply follow their advice. Because, in reality, he knew these things existed, but he didn’t really understand them.”

Daniel Sindhøj, a GP from Copenhagen, confirms this reality from the other side: as a doctor, he starts from the remaining symptoms and follows the train of thought until the disease is ruled out. If not, either the patient is happy to learn that the result comes back negative and they get better, or he refers the patient to a specialist.

Ryan’s odyssey is not rare among long Covid patients. However, Solenn Tanguy, president of the French patients’ association Winslow Santé Publique, says: “The diagnosis of long Covid depends on the patient’s ability to navigate the healthcare system until a diagnosis is reached.”

This disparity can also be seen between continents, warns the World Health Organisation (WHO), depending on countries' “resources, access to health and care services, population immunity, access to vaccines, and healthcare provider awareness of long Covid can be different”, says Leonardo Palumbo, Technical Officer in Community Engagement in the Health Security Division of WHO Europe.

Moreover, with over 200 symptoms listed by WHO, no valid biological markers, and fewer people testing themselves, it is easy to see why any doctor may find it difficult to diagnose long Covid.

Claus Desler Madsen is an Associate Professor at the University of Copenhagen and coordinator of Point Project, a European initiative working on post-acute Covid infection care by bridging the gap between scientific research and clinical applications. He says, “When you have this overall understanding that long Covid is just everything, then you're basically losing a filter”. He adds that it is even harder as there is a general idea among practitioners that with infectious diseases such as Covid, “you either die or get over it and can get back to work”.

Often, health workers end up psychologising patients. It is particularly true for women, who also face a 31% higher risk of developing long Covid according to a 2024 NIH study, and who generally have to navigate gender bias in health care.

And yet documentation and clinical knowledge on long Covid have existed from a very early stage in the pandemic. Mark Katz, epidemiologist in the Pandemic Threats, Communicable Diseases and Anti-Microbial Resistance Unit, Division of Health Security, WHO Regional Office for Europe, explains that a vetted clinical case definition for long Covid was published by the organisation as early as 2021.

Helping doctors help long Covid patients

Desler from the Point Project says: “Studies have shown that if you give a guideline, then one third of physicians will follow it. One third will follow it wrongly or misinterpret it. And one third will ignore it.” Sindhøj puts it plainly: “National guidelines are very formal and originated in the disease, whereas the patient presents symptoms where a lot of diseases should be considered. Therefore, they are not as useful in practical medicine”.

A workshop led by the Point Project at the annual GP conference Wonca in Lisbon last September gathered feedback on this issue. One participant summed up one of the main issues about medical guidelines: “for us, without us”.

This is the missing link the Point Project addresses. The consortium works on three parallel steps towards a practical tool for doctors to diagnose long Covid but also evaluate the risk for patients of developing a post-acute phase infection.

Ove Andersen, professor in emergency medicine and infectious disease, says: “The project targets first line doctors, because the first line doctor could be in an emergency department or the patient’s GP. It totally depends on where every single patient gets their first contact with the health system”.

Andersen’s team is building a tool around a predictive algorithm that will take in various variables so as to evaluate a patient’s risk of developing a long form of Covid or, depending on the inputs, if the patient has long Covid.

To do so, the project is collecting data on post-acute infection from an ongoing cohort of Covid patients to find biomarkers of the disease. These are wet biomarkers, such as blood, and dry biomarkers. “Dry biomarkers are everything we know from registers or patients’ records” explains Andersen: age, prior diseases, socioeconomic conditions, mental health… And they also add soft biomarkers, which are symptoms: dry cough, absence of taste etc.

Desler and Andersen insist on the importance of seeing patients as a whole in the case of lingering infections instead of working in speciality silos to avoid dead ends.

The tool is being tested so as to be effective on the ground. Desler explains that the aim is to “give physicians an opportunity to go in and understand why a guideline is pointing in one direction, rather than just to direct them without any explanation”.

From peer support to patient-driven resource

In the absence of accessible biomarkers and of “political will” to tackle long Covid as Tanguy from Winslow Santé Publique regrets, patients have organised themselves. Patients share information online. Ryan explains: “The first thing it did for me was to make me realise I’m not mad.”

Patients’ associations emerged early in the pandemic to structure peer support and centralise information. Tanguy explains: “We had to learn how to sift through the information, how to interpret a study, how to tell if it’s reliable, which means looking at its limitations and conflicts of interest; it’s incredibly complex”. They now also federate themselves across countries. Winslow Santé Publique is, for instance, part of Long Covid Rise Up.

WHO shifted to a patient-centric and engaged community approach during the pandemic, building its myth-busting resources with an informal working group including patients. Cristina Salvi, Regional Adviser, Community Resilience and Protection, Health Security Division, WHO Regional Office for Europe, explains: “It uses community engagement to identify myths and infodemic management approaches, such as the ‘truth sandwich’, to address false information by placing it between clear facts, reinforced with real human stories to build trust and empathy”.

These efforts unfold as the general context grows more difficult. Katz says funds to work on Covid are getting thinner even at WHO. Meanwhile, Desler adds: “We want to make sure that society continues to remember that Covid is still a problem now”. He adds, and Tanguy with him, that looking at individual organ failures without addressing their cause risks turning long Covid into “a burden” on healthcare systems and society.

Despite all the difficulties and despite the fact that even after the diagnostic odyssey, there may be no cure, Ryan says recognition still matters: “The diagnosis didn’t help with the treatment, because it doesn’t offer any therapeutic solution, but at least there’s an anomaly that helps health workers believe me.” Desler adds: “Even if long Covid patients cannot be given any treatment, at least a diagnosis can give them that identity.”