different symptoms depending on the variant

Lisbon, Portugal – The persistent symptoms observed during a “long Covid” appear different depending on the type of SARS-CoV2 variant that causes the infection, according to an Italian study whose results were presented at the ECCMID 2022 Congress (European Congress of Clinical Microbiology and Infectious Diseases). became diseases) [1]. These differences mainly concern neurological and neurosensory symptoms.

Among patients who remain symptomatic more than a month after infection, those infected in 2021, when the alpha variant of the coronavirus is prevalent, report muscle pain, insomnia, brain fog and anxiety more frequently than those infected in 2020 with the original strain of the virus were infected. On the other hand, they are much less affected by the loss of taste and smell.

We found no differences in cardiovascular or respiratory symptoms

“These differences can be observed at a neurological, neurosensory or psychological level. We found no differences in terms of cardiovascular or respiratory symptoms,” commented the study’s lead author, Dr. Michele Spinicci (Department of Clinical and Experimental Medicine, University of Florence, Italy), during his presentation.

A still poorly understood post-Covid syndrome

After infection with SARS-CoV2, the symptoms usually disappear within two to three weeks. However, symptoms may persist or recur in some people. If they last longer than three months, we speak of Post-Covid Syndrome or more commonly “Long Covid”.

According to the World Health Organization (WHO), 25% of people with Covid-19 still have symptoms more than a month after contracting it. At least 10% have ‘long Covid’ with symptoms lasting more than three months. The main risk factors are initial severity, number of symptoms in the acute phase, and female gender.

The most frequently reported symptoms of “long covid” are severe fatigue, discomfort after exertion, cognitive (lack of concentration, memory loss, etc.), sensory (buzzing, dizziness, etc.) disorders, but also headaches, breathing difficulties, persistent cough or even digestive disorders, sleep disorders , irritability.

Vagus nerve dysfunction involved?

Damage to the vagus nerve during infection with SARS-CoV2 could explain the persistence of certain symptoms. This is suggested by a small Spanish study, also presented during this ECCMID session dedicated to Post-Covid Syndrome. [2].

In this study, researchers evaluated the structure and function of the vagus nerve through various examinations in patients who developed Covid-19 with or without persistent symptoms. Ultrasound scans showed hyperechogenicity and thickening of the vagus nerve, signs of change, in long-Covid patients. In addition, swallowing disorders and a loss of mobility of the diaphragm occur more frequently.

“Our results suggest that vagus nerve dysfunction is an important pathophysiological feature of post-Covid syndrome,” commented Dr. However, the results need to be confirmed in other studies, she added.

the long covid remains poorly understood

Despite the proliferation of work on the subject, “the long Covid remains largely misunderstood,” commented Dr. Spinicci. The actual definition of post-Covid syndrome is still debated. “Data on the pathophysiology are lacking and the clinical manifestations are not yet well characterized”.

To learn more about this post-Covid syndrome, the infectious disease specialist and his team conducted a retrospective observational study of patients hospitalized for Covid-19. They therefore included 428 patients (59% men) who were treated as outpatients between June 2020 and June 2021 at the Careggi University Hospital in Florence (Italy). They were on average 64 years old.

Between 4 and 12 weeks after their hospital discharge, they were asked to participate in a follow-up visit, during which they answered a questionnaire to assess the possible presence of ongoing symptoms. At the same time, the researchers accessed the data on their medical history and the clinical development of Covid-19.

Mainly shortness of breath and chronic fatigue

The results show that more than three-quarters of patients reported at least one persistent symptom after a median of 53 days after hospitalization. The majority complained of shortness of breath (37% of patients), chronic fatigue (36%), trouble sleeping (16%), visual disturbances (13%), a feeling of brain fog (13%), and persistent cough (11%).

Analysis of medical data made it possible to identify risk factors. Patients who have developed a severe form of the disease that requires the prescription of an immunosuppressant such as tocilizumab are six times more likely to have persistent symptoms. People given oxygen have a 40% increased risk.

In addition to the severity of Covid-19, there is the risk factor associated with gender, as women have been found to be twice as likely to report post-Covid symptoms as men. On the other hand, patients with type 2 diabetes appear to be surprisingly less likely to develop persistent symptoms (60% risk reduction), which should be the subject of more detailed studies, the authors suggest.

By distinguishing between patients infected between March and December 2020, when the original SARS-Co2 strain was prevalent, and patients infected between January and April 2021, after the alpha variant became the majority, the researchers were able to significant differences observed in some persistent symptoms have been reported.

Less dysgeusia and anosmia in the alpha variant

If the symptom rate appears similar between the two groups, cognitive disorders described as mental fog (difficulty concentrating, forgetfulness, etc.) are more frequently reported by patients infected with the alpha variant (16% versus 10% in those infected in 2020). ). They are also more likely to complain of myalgia (10% vs. 4%) and anxiety or depression (13% vs. 6%).

Conversely, loss of smell (anosmia) was reported less frequently (2% vs. 12%), as were changes in taste (dysgeusia) (4% vs. 11%).

The authors state that the study is an observational study and therefore the causal relationship regarding the effects of the variants on the symptoms cannot be established. In addition, an infection with the alpha variant or with the original virus strain was not detected, but only suspected.

SARS-CoV2 variants appear to induce different long Covid phenotypes.

“Variants of SARS-CoV2 appear to induce different long Covid phenotypes. Further studies need to be carried out to better understand the influence of the variants, but also the impact of vaccination against Covid-19 on the development of symptoms,” concluded Dr. Spinicci.

Asked at the end of the session about the interpretation of the increased risk of anxiety and depression observed in 2021 infected patients, the researcher acknowledged that it could also be a consequence of the stress associated with an epidemiological situation of prolonged duration and related limitations .

Spinicci M, A post-COVID syndrome: a never-ending story, SARS-CoV-2 variants can induce different long COVID phenotypes, ESCMID 2022, presentation of April 23, 2022, Lisbon, Portugal.

Llados G, A post-COVID syndrome: a never-ending story, Vagus nerve dysfunction in the post-COVID-19 state, ESCMID 2022, Presentation 23 April 2022, Lisbon, Portugal.

Continue to follow Medscape in French Twitter.

Follow theheart.org | Medscape Cardiology Twitter.

Leave a Comment