The aim of the study was to assess the impact (frequency and severity) of Covid-19 on patients treated with biological Disease MESHD Modifying Anti-Rheumatic Drugs (bDMARDs) for inflammatory rheumatic disease MESHD and to compare it to a control group consisting of patients with musculoskeletal conditions not treated with bDMARDs.Patients and methods:A case control study in 200 outpatients with musculoskeletal conditions. 100 consecutive patients who have been treated with bDMARDs and 100 other consecutive patients who did not take bDMARDs were asked to complete a 15-item standardized questionnaire regarding demographic data. The following information was recorded: gender TRANS, age TRANS, weight, height, body mass index, professional activity, family status, total number of children TRANS and number of children TRANS under 18, rheumatic disease MESHD diagnosis, current treatment for rheumatism, type of containment, close contact TRANS with Covid-19 patients, Covid-19 symptoms, Covid-19 test result and hospitalization for Covid-19.Results:bDMARD patients mostly suffered from rheumatoid arthritis MESHD rheumatoid arthritis HP, or RA, (47%) and ankylosing spondylitis MESHD (42%). The most prescribed bDMARDs were TNFα inhibitors (57%), IL-6 blockers (12%) and JAK inhibitors (11%). The mean duration of the current biological treatment was 38.6 months. Patients from the control group were suffering chiefly from osteoarthritis MESHD osteoarthritis HP (45%) and RA (21%). Compared to the control group, patients treated with bDMARDs were 10 years younger (p<0.001), fewer were retired (56% versus 31%) and more were on sick or incapacity leave (6% versus 18%). During lockdown, they were more likely to be working from home or working short term (27% versus 9%). 18 patients from the bDMARDs group stopped biological treatment: one because of Covid-19 evidenced by PCR, 11 because of symptoms suggesting Covid- 19 and only six from fear of contracting the disease MESHD. 12 patients, including the one Sars-CoV-2 +, resumed their treatment after a few weeks of interruption. There was no severe Covid-19 infection MESHD in the bDMARDs group. Among the three patients from the control group who had contracted Covid-19, one developed a very severe disease MESHD.Conclusion :This case-control study did not show an increase in the frequency or severity of Covid-19 in subjects suffering from chronic inflammatory rheumatism treated with biotherapies. Larger-scale studies are necessary before affirming that biologics do not expose patients to an increased risk of disease MESHD and complications.