Reemergence of Dengue Virus Serotype 3, Brazil, 2023.

We characterized 3 autochthonous dengue virus serotype 3 cases and 1 imported case from 2 states in the North and South Regions of Brazil, 15 years after Brazil's last outbreak involving this serotype. We also identified a new Asian lineage recently introduced into the Americas, raising concerns about future outbreaks.

Severe Acute Respiratory Syndrome Coronavirus 2 P.2 Lineage Associated with Reinfection Case, Brazil, June-October 2020.

A 37-year-old healthcare worker from the northeastern region of Brazil experienced 2 clinical episodes of coronavirus disease. Infection with severe acute respiratory syndrome coronavirus 2 was confirmed by reverse transcription PCR in samples collected 116 days apart. Whole-genome sequencing revealed that the 2 infections were caused by the most prevalent lineage in Brazil, B.1.1.33, and the emerging lineage P.2. The first infection occurred in June 2020; Bayesian analysis suggests reinfection at some point during September 14-October 11, 2020, a few days before the second episode of coronavirus disease. Of note, P.2 corresponds to an emergent viral lineage in Brazil that contains the mutation E484K in the spike protein. The P.2 lineage was initially detected in the state of Rio de Janeiro, and since then it has been found throughout the country. Our findings suggest not only a reinfection case but also geographic dissemination of the emerging Brazil clade P.2.

More than just a common cold: Endemic coronaviruses OC43, HKU1, NL63, and 229E associated with severe acute respiratory infection and fatality cases among healthy adults.

Respiratory viral infection can cause severe disease and hospitalization, especially among children, the elderly, and patients with comorbidities. In Brazil, the official surveillance system of severe acute respiratory infection (SARI) investigates influenza A (IAV) and B (IBV) viruses, respiratory syncytial virus (RSV), adenovirus (HAdV), and parainfluenza viruses (hPIV 1-3). In Rio Grande do Sul (RS), Brazil, many fatalities associated with SARI between 2013 and 2017 occurred among patients without underlying diseases and for whom the causative agent had not been identified using official protocols. This cross-sectional study analyzed the presence of coronaviruses (HCoV), bocavirus (HBoV), metapneumovirus (hMPV), and rhinovirus in patients who died of SARI despite not having comorbidities, and that were negative for IAV, IBV, RSV, HAdV, and hPIV. Nasopharyngeal aspirates/swabs from patients were used for nucleic acid extraction. The presence of HCoVs OC43, HKU1, NL63, and 229E; HBoV; hMPV; and rhinovirus was assessed by quantitative reverse transcription-polymerase chain reaction. Clinical data were also analyzed. Between 2013 and 2017, 16 225 cases of SARI were reported in RS; 9.8% of the patients died; 20% of all fatal cases were patients without comorbidities and for whom no pathogen was detected using standard protocols. Analysis of 271 of these cases identified HCoV in nine cases; HBoV, hMPV, and rhinovirus were detected in 3, 3, and 10 cases, respectively. Of note, patients infected with HCoV were adults. Results reinforce the importance of including coronaviruses in diagnostic panels used by official surveillance systems because besides their pandemic potential, endemic HCoVs are associated to severe disease in healthy adults.

Re-emergence of Gamma-like-II and emergence of Gamma-S:E661D SARS-CoV-2 lineages in the south of Brazil after the 2021 outbreak.

BACKGROUND: We report a genomic surveillance of SARS-CoV-2 lineages circulating in Paraná, southern Brazil, from March 2020 to April 2021. Our analysis, based on 333 genomes, revealed that the first variants detected in the state of Paraná in March 2020 were the B.1.1.33 and B.1.1.28 variants. The variants B.1.1.28 and B.1.1.33 were predominant throughout 2020 until the introduction of the variant P.2 in August 2020 and a variant of concern (VOC), Gamma (P.1), in January 2021. The VOC Gamma, a ramification of the B.1.1.28 lineage first detected in Manaus (northern Brazil), has grown rapidly since December 2020 and was thought to be responsible for the deadly second wave of COVID-19 throughout Brazil. METHODS: The 333 genomic sequences of SARS-CoV-2 from March 2020 to April 2021 were generated as part of the genomic surveillance carried out by Fiocruz in Brazil Genomahcov Fiocruz. SARS-CoV-2 sequencing was performed using representative samples from all geographic areas of Paraná. Phylogenetic analyses were performed using the 333 genomes also included other SARS-CoV-2 genomes from the state of Paraná and other states in Brazil that were deposited in the GISAID. In addition, the time-scaled phylogenetic tree was constructed with up to 3 random sequences of the Gamma variant from each state in Brazil in each month of 2021. In this analysis we also added the sequences identified as the B.1.1.28 lineage of the Amazonas state and and the Gamma-like-II (P.1-like-II) lineage identified in different regions of Brazil. RESULTS: Phylogenetic analyses of the SARS-CoV-2 genomes that were previously classified as the VOC Gamma lineage by WHO/PANGO showed that some genomes from February to April 2021 branched in a monophyletic clade and that these samples grouped together with genomes recently described with the lineage Gamma-like-II. Additionally, a new mutation (E661D) in the spike (S) protein has been identified in nearly 10% of the genomes classified as the VOC Gamma from Paraná in March and April 2021.Finally, we analyzed the correlation between the lineage and the Gamma variant frequency, age group (patients younger or older than 60 years old) and the clinical data of 86 cases from the state of Paraná. CONCLUSIONS: Our results provided a reliable picture of the evolution of the SARS-CoV-2 pandemic in the state of Paraná characterized by the dominance of the Gamma strain, as well as a high frequencies of the Gamma-like-II lineage and the S:E661D mutation. Epidemiological and genomic surveillance efforts should be continued to unveil the biological relevance of the novel mutations detected in the VOC Gamma in Paraná.

Digital PCR detection of EGFR somatic mutations in non-small-cell lung cancer formalin fixed paraffin embedded samples.

BACKGROUND: Digital PCR (dPCR) is proposed to replace real time PCR and Sanger sequencing for detection and quantification of rare mutations, frequently unnoticed in the mass of tumoral cells. Screening of endothelial growth factor receptor (EGFR) mutations is mandatory before treatment with EGFR-targeted therapy with small-molecule tyrosine kinase inhibitors, which has been approved for the treatment of advanced non-small-cell lung cancer (NSCLC). OBJECTIVE: In order to establish a cost-effective method for detection of mutations, we optimized dPCR identification of EGFR mutations in exons 18-21, and determined dPCR sensitivity, limits of detection (LoD) and quantification (LoQ). METHODS: For clinical validation, we compared the performance of dPCR and castPCR in 57 NSCL formalin fixed paraffin embedded samples and 10 lung cancer-free formalin fixed paraffin embedded samples. RESULTS: EGFR mutations DEL19, p.L858R, p.G719X, p.L861Q and p.T790 M were detected by dPCR in 27 samples versus 11 detected by castPCR (p = 0.014). LoD was determined as 100 molecules of DNA/uL and LoQ as 1%. Most of the samples (87%) identified by competitive Allele-Specific TaqMan (castPCR) as wild-type and by dPCR as mutated, presented less than 10% mutated DNA molecules (mean 4.57%). Accuracy of dPCR was 94.44%, as measured with the assay recommended by the College of American Pathologists. CONCLUSION: These results indicated higher sensibility and specificity of dPCR for screening EGFR mutations in NSCLC biopsies, compared to castPCR.

Whole-Genome Characterization of a Novel Human Influenza A(H1N2) Virus Variant, Brazil.

We report the characterization of a novel reassortant influenza A(H1N2) virus not previously reported in humans. Recovered from a a pig farm worker in southeast Brazil who had influenza-like illness, this virus is a triple reassortant containing gene segments from subtypes H1N2 (hemagglutinin), H3N2 (neuraminidase), and pandemic H1N1 (remaining genes).

Oseltamivir-resistant influenza A(H1N1)pdm2009 strains found in Brazil are endowed with permissive mutations, which compensate the loss of fitness imposed by antiviral resistance.

The 2009 pandemic influenza A virus outbreak led to the systematic use of the neuraminidase (NA) inhibitor oseltamivir (OST). Consequently, OST-resistant strains, carrying the mutation H275Y, emerged in the years after the pandemics, with a prevalence of 1-2%. Currently, OST-resistant strains have been found in community settings, in untreated individuals. To spread in community settings, H275Y mutants must contain additional mutations, collectively called permissive mutations. We display the permissive mutations in NA of OST-resistant A(H1N1)pdm09 virus found in Brazilian community settings. The NAs from 2013 are phylogenetically distinct from those of 2012, indicating a tendency of positive selection of NAs with better fitness. Some previously predicted permissive mutations, such as V241I and N369K, found in different countries, were also detected in Brazil. Importantly, the change D344N, also predicted to compensate loss of fitness imposed by H275Y mutation, was found in Brazil, but not in other countries in 2013. Our results reinforce the notion that OST-resistant A(H1N1)pdm09 strains with compensatory mutations may arise in an independent fashion, with samples being identified in different states of Brazil and in different countries. Systematic circulation of these viral strains may jeopardise the use of the first line of anti-influenza drugs in the future.

COVID-19 in real world: Survival and medical costs of hospitalized patients in Brazil´s first wave.

OBJECTIVE: To evaluate survival and direct medical costs of patients admitted in private hospitals with COVID-19 during the first wave. METHODS: A retrospective, observational study analyzing survival and the economic data retrieved on hospitalized patients with COVID-19. Data from March 2020 to December 2020. The direct cost of hospitalization was estimated using the microcosting method with each individual hospitalization. RESULTS: 342 cases were evaluated. Median age of 61.0 (95% CI 57.0‒65.0). 194 (56.7%) were men. The mortality rate was higher in the female sex (p = 0.0037), ICU (p < 0.001), mechanical ventilation (p<0.001) and elderly groups. 143 (41.8%) patients were admitted to the ICU (95% CI 36.6%-47.1%), of which 60 (41.9%) required MV (95% CI 34.0%-50.0%). Global LOS presented median of 6.7 days (95% CI 6.0-7.2). Mean costs were US$ 7,060,00 (95% CI 5,300.94-8,819,00) for each patient. Mean cost for patients discharged alive and patients deceased was US$ 5,475.53 (95% CI 3,692.91-7,258.14) and US$ 12,955.19 (95% CI 8,106.61-17,803.76), respectively (p < 0.001). CONCLUSIONS: Patients admitted with COVID-19 in these private hospitals point to great economic impact, mainly in the elderly and high-risk patients. It is key to better understand such costs in order to be prepared to make wise decisions during the current and future global health emergencies.

Molecular Investigation Confirms Myotis Genus Bats as Common Hosts of Polychromophilus in Brazil.

Plasmodium spp. and some other blood parasites belonging to the order Haemosporida are the focus of many epidemiological studies worldwide. However, haemosporidian parasites from wild animals are largely neglected in scientific research. For example, Polychromophilus parasites, which are exclusive to bats, are described in Europe, Asia, Africa, and Oceania, but little is known about their presence and genetic diversity in the New World. In this study, 224 samples of bats from remaining fragments of the Atlantic Forest and Pantanal biomes, as well as urbanized areas in southern and southeastern Brazil, were analyzed for the presence of haemosporidian parasites by PCR of the mitochondrial gene that encodes cytochrome b (cytb). The PCR fragments of the positive samples were sequenced and analyzed by the Bayesian inference method to reconstruct the phylogenetic relationships between Polychromophilus parasites from bats in Brazil and other countries. Sequences from Brazilian lineages of Polychromophilus were recovered in a clade with sequences from Polychromophilus murinus and close to the one Polychromophilus sequence obtained in Panama, the only available sequence for the American continent. This clade was restricted to bats of the family Vespertilionidae and distinct from Polychromophilus melanipherus, a parasite species mainly found in bats of the family Miniopteridae. The detection of Polychromophilus and the genetic proximity to P. murinus were further confirmed with the amplification of two other genes (clpc and asl). We also found a Haemosporida parasite sequence in a sample of Noctilio albiventris collected in the Pantanal biome, which presents phylogenetic proximity with avian Haemoproteus sequences. Morphological and molecular studies are still needed to conclude and describe the Polychromophilus species in Brazilian Myotis bats in more detail and to confirm Haemoproteus parasites in bats. Nevertheless, these molecular results in Brazilian bats confirm the importance of studying these neglected genera.

Potential use of high-resolution melting analyses for SARS-CoV-2 genomic surveillance.

The pandemic caused by COVID-19 and the emergence of new variants of SARS-CoV-2 have generated clinical and epidemiological impacts on a global scale. The use of strategies for monitoring viral circulation and identifying mutations in genomic regions involved in host interaction are important measures to mitigate viral dissemination and reduce its likely complications on population health. In this context, the objective of this work was to explore the potential of high-resolution melting (HRM) analysis combined with one-step real-time reverse transcription PCR in a closed-tube system, as a fast and convenient method of screening for SARS-CoV-2 mutations with possible implications on host-pathogen interactions. The HRM analyses allowed the distinction of the Gamma, Zeta, Alpha, Delta, and Omicron variants against the predecessors (B.1.1.28, B.1.1.33) of occurrence in Brazil. It is concluded that the molecular tool standardized here has the potential to optimize the genomic surveillance of SARS-CoV-2, and could be adapted for genomic surveillance of other pathogens, due to its ability to detect, prior to sequencing, samples suggestive of new variants, selecting them more assertively and earlier for whole genome sequencing when compared to random screening.

Increased interregional virus exchange and nucleotide diversity outline the expansion of the chikungunya virus ECSA lineage in Brazil.

The emergence and reemergence of mosquito-borne diseases in Brazil such as Yellow Fever, Zika, Chikungunya, and Dengue have had serious impacts on public health. Concerns have been raised due to the rapid dissemination of the chikungunya virus (CHIKV) across the country since its first detection in 2014 in Northeast Brazil. Faced with this scenario, on-site training activities in genomic surveillance carried out in partnership with the National Network of Public Health Laboratories have led to the generation of 422 CHIKV genomes from 12 Brazilian states over the past two years (2021-2022), a period that has seen more than 312 thousand chikungunya fever cases reported in the country. These new genomes increased the amount of available data and allowed a more comprehensive characterization of the dispersion dynamics of the CHIKV East-Central-South-African (ECSA) lineage in Brazil. Tree branching patterns revealed the emergence and expansion of two distinct subclades. Phylogeographic analysis indicated that the northeast region has been the leading hub of virus spread towards other regions. Increased frequency of C>T transitions among the new genomes suggested that host restriction factors from the immune system such as ADAR and AID/APOBEC deaminases might be driving CHIKV ECSA lineage genetic diversity in Brazil.

SARS-CoV-2 intra-host diversity, antibody response, and disease severity after reinfection by the variant of concern Gamma in Brazil.

The rapid spread of the SARS-CoV-2 Variant of Concern (VOC) Gamma in Amazonas during early 2021 fueled a second large COVID-19 epidemic wave and raised concern about the potential role of reinfections. Very few cases of reinfection associated with the VOC Gamma have been reported to date, and their potential impact on clinical, immunological, and virological parameters remains largely unexplored. Here we describe 25 cases of SARS-CoV-2 reinfection in Brazil. SARS-CoV-2 genomic analysis confirmed that individuals were primo-infected with distinct viral lineages between March and December 2020 (B.1.1, B.1.1.28, B.1.1.33, B.1.195, and P.2) and reinfected with the VOC Gamma between 3 to 12 months after primo-infection. We found a similar mean cycle threshold (Ct) value and limited intra-host viral diversity in both primo-infection and reinfection samples. Sera of 14 patients tested 10-75 days after reinfection displayed detectable neutralizing antibodies (NAb) titers against SARS-CoV-2 variants that circulated before (B.1.*), during (Gamma), and after (Delta and Omicron) the second epidemic wave in Brazil. All individuals had milder or no symptoms after reinfection, and none required hospitalization. These findings demonstrate that individuals reinfected with the VOC Gamma may display relatively high RNA viral loads at the upper respiratory tract after reinfection, thus contributing to onward viral transmissions. Despite this, our study points to a low overall risk of severe Gamma reinfections, supporting that the abrupt increase in hospital admissions and deaths observed in Amazonas and other Brazilian states during the Gamma wave was mostly driven by primary infections. Our findings also indicate that most individuals analyzed developed a high anti-SARS-CoV-2 NAb response after reinfection that may provide some protection against reinfection or disease by different SARS-CoV-2 variants.

Increased interregional virus exchange and nucleotide diversity outline the expansion of chikungunya virus in Brazil.

The emergence and reemergence of mosquito-borne diseases in Brazil such as yellow fever, zika, chikungunya, and dengue have had serious impacts on public health. Concerns have been raised due to the rapid dissemination of the chikungunya virus across the country since its first detection in 2014 in Northeast Brazil. In this work, we carried out on-site training activities in genomic surveillance in partnership with the National Network of Public Health Laboratories that have led to the generation of 422 chikungunya virus genomes from 12 Brazilian states over the past two years (2021-2022), a period that has seen more than 312 thousand chikungunya fever cases reported in the country. These genomes increased the amount of available data and allowed a more comprehensive characterization of the dispersal dynamics of the chikungunya virus East-Central-South-African lineage in Brazil. Tree branching patterns revealed the emergence and expansion of two distinct subclades. Phylogeographic analysis indicated that the northeast region has been the leading hub of virus spread towards other regions. Increased frequency of C > T transitions among the new genomes suggested that host restriction factors from the immune system such as ADAR and AID/APOBEC deaminases might be driving the genetic diversity of the chikungunya virus in Brazil.

Genomic epidemiology unveils the dynamics and spatial corridor behind the Yellow Fever virus outbreak in Southern Brazil.

Despite the considerable morbidity and mortality of yellow fever virus (YFV) infections in Brazil, our understanding of disease outbreaks is hampered by limited viral genomic data. Here, through a combination of phylogenetic and epidemiological models, we reconstructed the recent transmission history of YFV within different epidemic seasons in Brazil. A suitability index based on the highly domesticated Aedes aegypti was able to capture the seasonality of reported human infections. Spatial modeling revealed spatial hotspots with both past reporting and low vaccination coverage, which coincided with many of the largest urban centers in the Southeast. Phylodynamic analysis unraveled the circulation of three distinct lineages and provided proof of the directionality of a known spatial corridor that connects the endemic North with the extra-Amazonian basin. This study illustrates that genomics linked with eco-epidemiology can provide new insights into the landscape of YFV transmission, augmenting traditional approaches to infectious disease surveillance and control.

Detection of RD(Rio) strain of Mycobacterium tuberculosis in tapirs (Tapirus terrestris) from a zoo in Brazil.

Tuberculosis is a chronic infection caused by strains of the Mycobacterium tuberculosis complex and occurs in both animal and human populations. The death of a tapir showing purulent material and a hard mass in the lungs at necropsy raised suspicion of a potential disease caused by mycobacteria species in a Brazilian zoo. Later, two other tapirs with similar signs died and were further investigated. Polymerase chain reaction (PCR) from bronco-alveolar lavages was performed, and both animals tested positive for the RD(Rio) strain of M. tuberculosis, which is a recently discovered Latin American-Mediterranean sublineage and the main cause of human tuberculosis in Rio de Janeiro, Brazil. To investigate the possibility of human infection and the source of transmission, all 50 zoo employees underwent tuberculin skin testing; four were reactive, but radiographic exams and direct sample staining did not suggest tuberculosis. Thus, direct human to animal transmission was not proven. However, the presence of RD(Rio) M. tuberculosis in tapirs highlights the lack of attention to diseases that human beings may transmit to wildlife.

An outbreak of tuberculosis by Mycobacterium bovis in coatis (Nasua nasua).

Mycobacterium tuberculosis complex, which includes Mycobacterium bovis, infrequently causes severe or lethal disease in captive wildlife populations. A dead coati from a wildlife triage center showing pulmonary lesions compatible with tuberculosis had raised suspicion of a potential disease caused by mycobacteria species and was further investigated. Four native coatis (Nasua nasua) with suspected mycobacterial infection were sedated, and bronchoalveolar lavages and tuberculin skin tests (TSTs) were performed. All animals tested positive upon TST. Mycobacterial culturing, Ziehl-Neelsen staining, and genetic testing were performed on postmortem samples and the etiologic agent was identified as M. bovis. Molecular genetic identification using a polymerase chain reaction panel was crucial to achieving a definitive diagnosis.

A case-control study to determine the effectiveness of a tetravalent dengue vaccine in the state of Paraná, Brazil.

Background: The Brazilian state of Paraná conducted a mass vaccination campaign against dengue with the tetravalent attenuated vaccine CYD-TDV. The campaign targeted thirty endemic municipalities. The objective of this study was to assess the effectiveness of CYD-TDV in preventing symptomatic virologically confirmed dengue cases according to specific age groups in five of the municipalities. Methods: A case-control study was carried out in the five most populous municipalities targeted by the vaccination, with a vaccine uptake of 25%. Symptomatic dengue cases were identified by the municipal health departments. The age groups targeted were 15-18 and 19-27 in four municipalities and 9-14 and 28-44 in one municipality. All cases were confirmed by real time reverse transcription quantitative polymerase chain reaction (RT-qPCR). For each case, two controls were selected: a neighbourhood control and a workplace or school/college control, matched by age group. A conditional logistic regression model was used to determine the odds ratio for vaccination and the vaccine effectiveness. Findings: Study participants included 618 RT-qPCR-confirmed dengue cases and 1,236 matched controls (with a non-reactive dengue IgM serologic test). Vaccine effectiveness against dengue due to any serotype was 11·1% (95% CI: -19·0%; 33·6%). Effectiveness against DENV-1 was 33·3% (95% CI: -5·0%; 57·6%) and against DENV-2 was -56·7% (95% CI: -142·2%; -5·0%). No DENV-3 was detected. The vaccine was significantly effective in the prevention of DENV-4 cases (VE = 93·3%; 95% CI: 47·7%; 99·2%). Interpretation: CYD-TDV was effective in the prevention of symptomatic cases due to DENV-4, but not due to any serotype. The low dengue seroprevalence in the target population could possibly be related to these results. Funding: This study was supported through a grant to the Sabin Vaccine Institute from Sanofi-Pasteur. Sanofi-Pasteur had no role in the study design, protocol development, data collection, analysis, or publication of results.

Novel duplex RT-qPCR for animal rabies surveillance.

Rabies is a lethal zoonosis affecting mammals worldwide. Diagnosis of rabies follows international standard protocols, primarily relying on direct immunofluorescence (DI) followed by mouse inoculation test (MIT). WHO recommends molecular biology techniques such as RT-qPCR for replacing MIT to diagnose rabies in animal samples. Recently, a real-time PCR protocol that detects all rabies virus variants identified worldwide was validated. This assay is a pan-Lyssavirus TaqMan quantitative RT-PCR called LN34. A modified LN34 assay protocol was tested at the Paraná State Reference Laboratory (Lacen/PR) using animal samples previously tested by DI and MIT, the gold standard (GS). This method has been changed to a RT-qPCR duplex format to better fit the diagnostic routine. The new assay was called duplex LN34 and ß-actin RT-qPCR. All the 88 samples evaluated using the GS test, modified pan-Lyssavirus TaqMan RT-qPCR and duplex LN34 and ß-actin RT-qPCR showed 100% agreement with each other. This novel duplex RT-qPCR protocol has shown adequate diagnostic performance and may be used in research and surveillance purposes, replacing the standard MIT and ending mice use for rabies diagnosis.

Genetic characterization of Chikungunya virus circulating in individuals from Paraná, Brazil.

Phylogenetic analysis carried out in several Brazilian regions shows the circulation of the Asian and East-Central South African (ECSA) Chikungunya virus (CHIKV) genotypes in the country. Until now, there are no genetic studies about CHIKV strains circulating in the South region. In this study, we sequenced 5 new partial sequences of the CHIKV Envelope 1 gene from strains detected in Paraná state during the years 2016-2017. Maximum likelihood and neighbor-joining trees grouped all sequences in Brazilian branches within ECSA genotype and comparative analysis did not show E1-A226V mutation. However, we identified E1-K211T amino acid substitution in a sample demonstrating the dispersion of mutant strains in the country.

Clinical trial and detection of SARS-CoV-2 by a commercial breath analysis test based on Terahertz technology.

Public health threats such as the current COVID-19 pandemics have required prompt action by the local, national, and international authorities. Rapid and noninvasive diagnostic methods may provide on-site detection and immediate social isolation, used as tools to rapidly control virus spreading. Accordingly, the aim of the present study was to evaluate a commercial breath analysis test (TERA.Bio®) and deterministic algorithm for detecting the SARS-CoV-2 spectral signature of Volatile Organic Compounds present in exhaled air samples of suspicious persons from southern Brazil. A casuistic total of 70 infected and 500 non-infected patients were sampled, tested, and results later compared to RT-qPCR as gold standard. Overall, the test showed 92.6% sensitivity and 96.0% specificity. No statistical correlation was observed between SARS-CoV-2 positivity and infection by other respiratory diseases. Further studies should focus on infection monitoring among asymptomatic persons. In conclusion, the breath analysis test herein may be used as a fast, on-site, and easy-to-apply screening method for diagnosing COVID-19.