Protocol for a prospective quasi-experimental study on SARS-CoV-2 transmission during outdoor sports events in France: the COVID-ESO project.

INTRODUCTION: The spread of SARS-CoV-2 and its variants in the community remains a major concern despite the application of control measures including the banning of mass sporting events. The circulation of SARS-CoV-2 within the general population, and potentially within the population practicing outdoor sports activities, suggests contexts conducive to the transmission of the virus. We hypothesise that outdoor sports events (OSEs) do not present a higher risk of SARS-CoV-2 contamination. The objective of the COVID-ESO project is to measure if individuals participating in OSE present a similar risk of SARS-CoV-2 transmission compared with individuals not participating in OSE, in France. METHODS AND ANALYSIS: The COVID-ESO project is a prospective, quasi-experimental study to be conducted in volunteer individuals likely to participate in OSE. Six events are targeted across France to be included. Three sport trials will be eligible for the study: running, cycling and triathlon. Each individual participating in the OSE will choose one of his or her usual training partner to be eligible for the unexposed control group. Individuals will be matched (1:1) on age, sex and the district of residence. Individuals assigned to the exposed group will participate in the OSE, whereas individuals assigned to the unexposed group will not participate in the OSE. All individuals will be asked to perform saliva tests on the day of the event and 7 days after the event. A questionnaire including sociodemographic, clinical and exposure data to SARS-CoV-2 will be sent by email for both groups on the day before the event and 7 days after the event. Differences in SARS-CoV-2 infection rates between the exposed versus the unexposed group will be analysed by fitting a conditional logistic regression model, adjusted for potential confounders. As the sport events unfold, data will be analyzed by performing sequential meta-analyses. ETHICS AND DISSEMINATION: This protocol has been approved by the ethical committee. Ethical approval has been obtained for the Clinical research and committee of South West of France, 10 June 2021. COMITE DE PROTECTION DES PERSONNES DU SUD-OUEST ET OUTRE-MER 4 under the reference number 21.03.23.71737/CPP2021-04-045 a COVID/2021-A00845-36. Findings generated from this study will be shared to national health and sport authorities.

Diagnosis of dermatophytosis: an evaluation of direct examination using MycetColor® and MycetFluo®.

Dermatophytes are an important cause of superficial fungal infection. Direct examination of skin, nail, or hair samples remains essential in diagnosis, as it provides a quick response to the clinician. However, mycological analysis, including direct examination and culture, often lacks sensitivity. The use of stains or fluorochromes may enhance the performance of direct examination. We analyzed 102 samples from patients with suspected dermatophytosis in 4 different diagnostic mycology laboratories. Two reagents, MycetColor® and MycetFluo®, which use Congo red and calcofluor dye, respectively, were evaluated for the direct microscopic examination of skin, hair, and nail specimens. The results were compared to those of culture and conventional direct examination. Both reagents were able to clarify the specimens and also to specifically stain fungal elements. Microscopic examination of the specimens was greatly facilitated with MycetFluo®, which allowed a higher number of positive cases to be detected compared to the other methods.

Efficient diagnosis of vulvovaginal candidiasis by use of a new rapid immunochromatography test.

The clinical symptoms of vulvovaginal candidiasis (VVC) are nonspecific, and misdiagnosis is common, leading to a delay in the initiation of antifungal treatment. We evaluated a new immunochromatography test (ICT), the CandiVagi assay (SR2B, Avrille, France), for the rapid diagnosis of VVC. This test, which employs an immunoglobulin M antibody directed against the beta-1,2-mannopyranosyl epitopes found in the yeast cell wall, was compared with direct microscopic examination and culture of vaginal swabs. Two-hundred five women were investigated, including 130 women with symptomatic vaginitis and 75 asymptomatic controls. Two vaginal swabs were obtained from each woman: one was used to prepare a wet mount and Gram-stained preparations for direct microscopic examination and was also cultured on Sabouraud dextrose agar for the isolation of Candida spp., and the second swab was used for ICT. The sensitivities of microscopic examination, culture, and ICT for the diagnosis of VVC were 61%, 100%, and 96.6%, respectively, while the specificities of the three methods were 100%, 82%, and 98.6%, respectively. ICT had a negative predictive value of 98.6%, a positive predictive value of 96.6%, and an efficiency of 98%. ICT provided a rapid result and a better compromise between sensitivity and specificity than conventional microscopy and culture for the diagnosis of VVC. This easy-to-perform diagnostic test will be useful to practitioners treating women with symptoms of vaginitis.

Development and evaluation of a rapid latex agglutination test using a monoclonal antibody to identify Candida dubliniensis colonies.

Cell components of the dimorphic pathogenic fungus Candida dubliniensis were used to prepare monoclonal antibodies (MAbs). One MAb, designated 12F7-F2, was shown by indirect immunofluorescence to be specific for a surface antigen of Candida dubliniensis yeast cells. No reactivity was observed with other fungal genera or with other Candida species, including Candida albicans, that share many phenotypic features with C. dubliniensis. The use of different chemical and physical treatments for cell component extraction suggested that the specific epitope probably resides on a protein moiety absent from C. albicans. However, we failed to identify the target protein by Western blotting, owing to its sensitivity to heat and sodium dodecyl sulfate. MAb 12F7-F2 was further used to develop a commercial latex agglutination test to identify C. dubliniensis colonies (Bichro-dubli Fumouze test; Fumouze Diagnostics). The test was validated on yeast strains previously identified by PCR and on fresh clinical isolates; these included 46 C. dubliniensis isolates, 45 C. albicans isolates, and other yeast species. The test had 100% sensitivity and specificity for C. dubliniensis isolated on Sabouraud dextrose, CHROMagar Candida, and CandiSelect media and 97.8% sensitivity for C. dubliniensis grown on Candida ID medium. The test is rapid (5 min) and easy to use and may be recommended for routine use in clinical microbiology laboratories and for epidemiological investigations.