Quantitative analysis of RT-PCR test results for SARS-CoV-2 diagnostics across Poland during COVID-19 pandemic: Comparison between early stage and major pandemic waves in 2020 and 2021 with reference to SARS-CoV-2 variants.

PURPOSE: From April to September 2020, Poland was minimally affected by COVID-19 compared to other EU countries. We aimed to investigate the risks of false reverse transcription polymerase chain reaction (RT-PCR) results during the first wave (compared to later waves), that rises when cycle threshold (Ct) of positive result is close to limit of detection (LOD). MATERIALS/METHODS: We analyzed Ct values of SARS-CoV-2 positive RT-PCR results of 7726 patients in Poland from April-September 2020. SARS-CoV-2 positive RT-PCR results of 14,534 patients in the 2nd-3rd wave and 10,861 patients in the 4th-5th pandemic waves were used. Statistical analysis was based on one-way analysis of variance. To verify, 95% confidence intervals with Bonferroni correction were computed. Incidence of SARS-CoV-2 variants in Poland was analyzed using Whole Genome Sequencing from 923 (3.6%) patients. RESULTS: The mean Ct of RT-PCR positive test results analyzed ranged between 22.89 and 26.71 depending on the month of the results collection. The differences between months were significant (p â€‹< â€‹0.001). Differences in Ct were observed between age groups, with younger patients displaying higher Ct values, however, major trends over time were paralleled between age groups. CONCLUSIONS: The mean Ct of the tested RT-PCR positive test results was lower than 35 which is considered an upper borderline for reliable positive results of the assay. Therefore, most COVID-19 cases recorded in Poland from April to September 2020 were detected with minor risks of inaccuracy. Data from a single center exhibited greater consistency for both virus Ct level and SARS-CoV-2 virus variant identification.

Factors Associated with Falls During Hospitalization for Coronavirus Disease 2019 (COVID-19).

BACKGROUND During the current Coronavirus Disease 2019 (COVID-19) pandemic, falls have been identified as a potential presenting symptom in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; however, data on factors increasing fall risk in this patient population are limited. This study aimed to examine the factors that may predispose hospitalized COVID-19 disease patients to falls. MATERIAL AND METHODS In this retrospective observational study, hospitalized COVID-19 disease patients were examined for fall incidence, as well as demographics, comorbidities, and clinical and laboratory data. Patients were stratified according to their fall status and their characteristics were compared using Fisher's exact test or Mann-Whitney U test. A total of 312 hospitalized COVID-19 disease patients were enrolled (median age, 75 years; males, 51.3%), of whom 11 (3.5%) fell. RESULTS There was a greater prevalence of falls among patients who experienced arrhythmias than those that did not (28.6% vs 1.7%; P<0.001). Additionally, a significantly greater proportion of those that were discharged to the internal ward and to the intensive care unit fell (10.3% and 10.0%, respectively) compared to those that were discharged home (1.6%, P=0.008). Thyroid-stimulating hormone (TSH) was significantly elevated in patients who fell (5.3 vs 0.97 µIU/mL, P=0.013), while alanine aminotransferase (ALT) was significantly lower in those who fell (17.1 vs 33.5 IU/L, P=0.041). CONCLUSIONS Arrhythmias may be an important predisposing factor for falls in COVID-19 disease patients and fall prevention programs should prioritize interventions directed at this vulnerable patient population.

Comparison of anti-SARS-CoV-2 IgG and IgA antibody responses post complete vaccination, 7 months later and after 3rd dose of the BNT162b2 vaccine in healthy adults.

BACKGROUND: The mRNA Covid-19 vaccine (BNT162b2) is administered in two doses with 21 days interval. On 4th October 2021 European Medicines Agency approved administration of a booster dose in at least 6 months after the second dose for people aged 18 years and older. OBJECTIVES: In the present study we compare the anti-SARS-COV-2 IgG and IgA antibody responses post complete vaccination, 7 months later and after the 3rd (booster) dose of the BNT162B2 vaccine in healthy adults. STUDY DESIGN: The levels of vaccine IgG and IgA antibodies to SARS-CoV-2 were assessed in serum samples obtained from individuals vaccinated with two doses and a booster of BNT162b2 vaccine. Samples were tested using the SARS-CoV-2 receptor-binding domain (RCB) IgG and IgA semi-quantitative commercial ELISA assay. RESULTS: The geometric mean of the anti-SARS-COV-2 IgG and IgA antibody level 7 months after vaccination of 90 healthy adults with BNT162B2 vaccine decreased significantly from 12.0 to 5.4 and 5.6 to 2.3, respectively. After the third dose of the same vaccine, the antibody level increased again, to values higher than at the beginning after the second dose. CONCLUSIONS: Significant decrease of antibody levels within a few months after full vaccination could result in the higher risk of SARS-CoV-2 infection, especially when new variants of the virus emerge. The booster could be crucial for protection against new SARS-CoV-2 variants. The antibody level seems to decrease slower in vaccinated individuals with history of COVID-19 and in younger individuals.

Stanowisko Komitetu Zdrowia Publicznego Polskiej Akademii Nauk w sprawie szczepień przeciw COVID-19

Public health community worldwide encouraged by successes of former campaigns have always accepted vaccination as the most effective way to handle infectious diseases pandemics. Even before the outburst of SARS-CoV-2 pandemic in many countries mandatory vaccination against many diseases, especially child related had been implemented. From among 193 countries under study in as many as 105 (54%) such obligation existed and in 62 of them (59%) at least one form of punishment or harm for those opposing was involved. Following this sort of available solutions and facing COVID-19 pandemic disaster the authors on behalf of the Public Health Committee of the Polish Academy of Science recommend to the government implementation od mandatory vaccination against COVID-19 for all workers in sectors of health care, education and welfare.

Healthcare workers highly affected during the COVID-19 epidemic wave in Poland prior to vaccination availability: seroprevalence study.

BACKGROUND: The aim of the study was to assess seroprevalence of anti-SARS-CoV-2 antibodies among healthcare workers (HCW) before introduction of vaccination, in selected areas in Poland as well as to identify potential risk factors and estimate the cumulative incidence of COVID-19 infections in this population. MATERIAL AND METHODS: The authors conducted a sero-epidemiological, cross-sectional study among HCW of 5 non-COVID-19 hospitals in Poland. The recruitment took place in December 1-23, 2020, all HCW at selected hospitals could volunteer into the study. All persons were screened with rapid SARS-CoV-2 IgM/IgG tests in capillary blood. In case of positive result, 5 ml of venous blood was drawn for confirmatory testing with ELISA assay. The authors estimated prevalence of laboratory confirmed anti-SARS-CoV-2 antibody presence and examined factors associated with positive result. Cumulative incidence was estimated applying 2-source capture-recapture method to serology results and self-report of past infection. RESULTS: Out of 1040 HCW included in the analysis, one-fourth (25.2%) received a positive result for anti-SARS-CoV-2 antibodies by ELISA test, the prevalence among women was 25.3% (95% CI: 22.5-28.4) and 24.6% (95% CI: 19-31.2) among men. The prevalence of anti-SARS-CoV-2 antibodies was the highest among respondents who declared home contact with a confirmed COVID-19 case, 43.9% (95% CI: 32.4-56.1). It was also elevated among those who indicated contact with patients with COVID-19, 32.5% (95% CI: 26.7-38.8) and business contacts, including at the workplace, 28.9% (95% CI: 22.5-36.3). The estimated cumulative incidence of COVID-19 infections in the population, using the capture-recapture method was 41.2% (95% CI: 38.1-44.2). CONCLUSIONS: Healthcare workers remained at increased risk of infection largely due to work-related contacts with infected patients, although home exposure was also common. Estimated cumulative incidence is higher than the antibody prevalence, which indicates the need to monitor HCW for possible immunity waning, also post-immunization immunity. Med Pr. 2022;73(2):109-23.

Characterization of the significant decline in humoral immune response six months post-SARS-CoV-2 mRNA vaccination: A systematic review.

Accumulating evidence shows a progressive decline in the efficacy of coronavirus disease 2019 (COVID-19) (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) messenger RNA (mRNA) vaccines such as Pfizer-BioNTech (mRNA BNT161b2) and Moderna (mRNA-1273) in preventing breakthrough infections due to diminishing humoral immunity over time. Thus, this review characterizes the kinetics of anti-SARS-CoV-2 antibodies after the second dose of a primary cycle of COVID-19 mRNA vaccination. A systematic search of the literature was performed and a total of 18 articles (N = 15 980 participants) were identified and reviewed. The percent difference of means of reported antibody titers was then calculated to determine the decline in humoral response after the peak levels postvaccination. Findings revealed that the peak humoral response was reached at 21-28 days after the second dose, after which serum levels progressively diminished at 4-6-month postvaccination. Additionally, results showed that regardless of age, sex, serostatus, and presence of comorbidities, longitudinal data reporting antibody measurement exhibited a decline of both anti-receptor binding domain immunoglobulin G (IgG) and anti-spike IgG, ranging from 94% to 95% at 90-180 days and 55%-85% at 140-160 days, respectively, after the peak antibody response. This suggests that the rate of antibody decline may be independent of patient-related factors and peak antibody titers but mainly a function of time and antibody class/molecular target. Hence, this study highlights the necessity of more efficient vaccination strategies to provide booster administration in attenuating the effects of waning immunity, especially in the appearance of new variants of concerns.

Prevalence and Sociodemographic Factors Associated with Overweight and Obesity among Adults in Poland: A 2019/2020 Nationwide Cross-Sectional Survey.

Detailed characteristics of the weight status of the population is necessary for the effective prevention of health disorders, e.g., through personalized nutrition education. This study aimed to characterize weight status and identify sociodemographic factors associated with overweight/obesity in a representative sample of adult inhabitants of Poland. This cross-sectional study was carried out from July 2019 to February 2020 on a representative nationwide sample of individuals aged 18+ in Poland. The study consisted of two parts: questionnaire survey and anthropometric measurements. The body mass index was calculated. Data on 1831 adults (50.3% females; mean age 51.7 ± 19.9 years) were included in this analysis. The prevalence of overweight was 42.2% (52.4% among males and 32.0% among females). Of the 1831 participants, 16.4% were obese (16.5% of males and 16.2% of females). Out of 11 factors analyzed in this study, only 5 were significantly associated with overweight/obesity. Males, older participants, occupationally active individuals, those living in rural areas and individuals with at least one chronic disease had greater odds of overweight/obesity. This study demonstrated a high prevalence of overweight and obesity among adults in Poland. This is the most up-to-date representative study on nutritional status carried out before the COVID-19 pandemic.

The Prevalence of Acute Respiratory Distress Syndrome (ARDS) and Outcomes in Hospitalized Patients with COVID-19-A Study Based on Data from the Polish National Hospital Register.

Acute respiratory distress syndrome (ARDS) is a serious complication of COVID-19. This study aimed to evaluate the prevalence of ARDS among patients hospitalized with COVID-19 in Poland as well as to characterize clinical outcomes in patients hospitalized with COVID-19-associated ARDS. This is a retrospective, secondary analysis of epidemiological data from 116,539 discharge reports on patients hospitalized with COVID-19 in Poland between March and December 2020. The overall prevalence of ARDS was 3.6%, respectively 2.9% among females, and 4.4% among males (p < 0.001). Of the 4237 patients hospitalized with COVID-19-associated ARDS, 3764 deaths were reported (88.8%). Participants aged 60 years and over had more than three times higher odds of COVID-19-associated ARDS. Men had higher odds of COVID-19-associated ARDS than women (OR = 1.55; 95% CI: 1.45-1.65; p < 0.001). Patients with COVID-19 and diabetes had higher odds of COVID-19-associated ARDS (OR = 1.16; 95% CI: 1.03-1.30; p = 0.01). Among patients with COVID-19-associated ARDS, older age, male sex (OR = 1.27; 95% CI: 1.03-1.56; p = 0.02), and presence of cardiovascular diseases (OR = 1.26; 95% CI: 1.00-1.59; p = 0.048) were significantly associated with the risk of in-hospital death. Among patients hospitalized with COVID-19 in Poland, the prevalence of ARDS was relatively low, but the in-hospital mortality rate in patients with COVID-19-associated ARDS was higher compared to other EU countries.

Characteristics and Clinical Outcomes of 116,539 Patients Hospitalized with COVID-19-Poland, March-December 2020.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019 (COVID-19). This study aimed to characterize patients hospitalized with COVID-19 in Poland between March and December 2020, as well as to identify factors associated with COVID 19-related risk of in-hospital death. This retrospective analysis was based on data from the hospital discharge reports on COVID-19 patients hospitalized in Poland between March and December 2020. A total of 116,539 discharge reports on patients hospitalized with COVID-19 were analyzed. Among patients with COVID-19, 21,490 (18.4%) died during hospitalization. Patients over 60 years of age (OR = 7.74; 95%CI: 7.37-8.12; p < 0.001), men (OR = 1.42; 95%CI: 1.38-1.47; p < 0.001) as well as those with cardiovascular diseases (OR = 1.51; 95%CI: 1.46-1.56; p < 0.001) or disease of the genitourinary system (OR = 1.39; 95%CI: 1.31-1.47; p < 0.001) had much higher odds of COVID 19-related risk of in-hospital death. The presence of at least one comorbidity more than doubled the COVID 19-related risk of in-hospital death (OR = 2.23; 95%CI: 2.14-2.32; p < 0.01). The following predictors of admission to ICU were found in multivariable analysis: age over 60 years (OR: 2.03; 95%CI: 1.90-2.16), male sex (OR: 1.79; 95%CI: 1.69-1.89), presence of at least one cardiovascular disease (OR: 1.26; 95%CI: 1.19-1.34), presence of at least one endocrine, nutritional and metabolic disease (OR: 1.17; 95%CI: 1.07-1.28).

Hospitalizations for COVID-19 in Poland: a study based on data from a national hospital register.

INTRODUCTION COVID­19 has been identified by the World Health Organization as a pandemic. Poland introduced extensive antiepidemic measures relatively early in order to slow down the spread of the disease. OBJECTIVES The study aims to present recent data on COVID­19 hospitalizations during the first months of the disease outbreak in Poland. PATIENTS AND METHODS This is a retrospective, population­based study conducted using hospital discharge records that included a diagnosis of COVID-19. Data were obtained from the National Institute of Public Health, where they had been originally collected for a Polish hospital morbidity study. They included 8840 hospitalization records from the period between February and September 2020. RESULTS Overall, there were 8252 records of patients hospitalized for COVID­19 for the first time, which accounted for 93% of all hospitalizations. The study group consisted of 4161 men (50.4%) and 4091 women (49.6%). Significantly more patients from urban than rural areas were hospitalized (21.8 per 100 000 vs 20.5 per 100 000; P <0.02). In the period subject to analysis, 1073 in­hospital deaths were observed (13% of all patients), 965 of which occurred during first­time hospitalizations (11.7% of all patients). In the study group, patients who died during hospitalization compared with those who survived hospitalization were significantly older, more frequently lived in urban areas, and had more comorbidities. CONCLUSIONS The findings of our study, especially the differences between survivors and nonsurvivors with COVID-19, may be helpful in recognizing patients requiring special medical care and preventive measures during hospitalization.

Ozone disinfection of community pharmacies during the COVID-19 pandemic as a possible preventive measure for infection spread.

The COVID-19 pandemic is currently one of the major global health and economic challenges. An efficient method for reducing the transmission of the virus is a still unmet medical need. Existing experimental data have shown that coronavirus survival is negatively impacted by ozone, high temperature, and low humidity. Therefore, it is feasible to use area ozonation in pharmacies - the front line of the healthcare system. Nevertheless, further work is needed to evaluate the effectiveness of ozone disinfection to reduce the transmission of this virus in pharmacies, hospitals, and other public environments. Med Pr. 2021;72(5):529-34.

The first SARS-CoV-2 genetic variants of concern (VOC) in Poland: The concept of a comprehensive approach to monitoring and surveillance of emerging variants.

PURPOSE: We analyzed the SARS-CoV-2 genome using our integrated genome analysis system and present the concept of a comprehensive approach to monitoring and surveillance of emerging variants. MATERIAL/METHODS: A total of 69 SARS-CoV-2 positive samples (with Ct value â€‹≤ â€‹28) were tested. Samples included in this study were selected from 7 areas of eastern Poland. All samples were sequenced on an Illumina MiSeq platform using a 300-cycle MiSeq Reagent Kit v2. BWA was used for reads mapping on the reference SARS-CoV-2 sequence. SAMTools were used for post-processing of reads to genome assembly. Pango lineage and Nexstrain were used to identify variants and amino acid mutations. Statistical analysis was performed with R 4.0.2. RESULTS: This study shows the first confirmed case of SARS-CoV-2 in Poland with the lineage B.1.351 (known as 501Y.V2 South African variant), as well as another 18 cases with epidemiologically relevant lineage B.1.1.7, known as British variant. Supplementary analysis of SARS-CoV-2 sequences deposited in GISAID shows that the share of a new variant can change rapidly within one month. In addition, we show a complete, integrated concept of a networked system for analyzing the variability of the SARS-CoV-2 genome, which, used in the present study, generated data and a variant report within 6 days. CONCLUSION: The analyzed viral genomes showed considerable variability with simultaneous clear distinction of local clusters of genomes showing high similarity. Implementing real-time monitoring of new SARS-CoV-2 variants in Poland is urgently needed, and our developed system is available to be implemented on a large scale.

[Health protection of employees against SARS-CoV-2 coronavirus infection causing the COVID-19 disease - the current state of knowledge and recommendations]. / Ochrona zdrowia pracujacych przed zakazeniem koronawirusem SARS-CoV-2 wywolujacym COVID-19 ­ aktualny stan wiedzy i zalecenia.

The COVID-19 pandemic, despite the restrictions and preventive measures applied, has rapidly spread and reached Poland. The adaptation to the dynamically changing epidemiological situation requires a prompt implementation of effective preventive measures. The aim of the publication is to provide current knowledge to all persons involved in the preventive care system, i.e., employees, employers and professionals of occupational medicine, about the epidemiological situation related to SARS­CoV- 2, as well as recommendations and possible solutions. In order to analyze these issues, a review of literature was conducted based on medical research databases: PubMed, SCOPUS, and the Web of Science Core Collection. The literature was supplemented with studies found on websites of the Ministry of Health and the World Health Organization. Data on the cases of and deaths due to COVID-19 come from reports provided by the Ministry of Health, data published on the websites of the European Center for Disease Prevention and Control, and ourworldindata.org. By the time of submitting the publication, 34 154 cases and 1444 deaths due to coronavirus had been recorded in Poland. Data from published studies suggest that the virus is mainly transmitted via droplets or through contact with contaminated objects and surfaces. Therefore, in the absence of an effective vaccine, preventive actions are based mainly on strategies that minimize the risk of pathogen transmission. In addition to discussing the current epidemiological situation, diagnostic procedures, risk groups and COVID-19 characteristics, the paper presents recommendations and proposed solutions for employers and employees regarding the prevention of SARS­CoV- 2, along with currently applicable laws and recommendations on employee prophylactic examinations during the pandemic. Subsequently, COVID-19 was discussed in the aspect of an occupational disease and other health threats related to the pandemics. The epidemiological situation regarding coronavirus indicates the need to take immediate and effective actions to minimize infection transmission among employees, and to develop procedures for a quick and effective ability to locate the COVID-19 outbreaks in workplaces. Med Pr. 2021;72(1):69-87.

Flu Vaccinations in Pharmacies-A Review of Pharmacists Fighting Pandemics and Infectious Diseases.

The phenomenon of population ageing observed over recent years involves growing healthcare needs and the limited staffing and financing of healthcare systems, and as such demands some functional changes in the healthcare model in many countries. This situation is particularly significant in the face of a pandemic, e.g., flu, and currently COVID-19.As well as social education, preventive vaccinations are the most effective method of fighting the infectious diseases posing a special threat to seniors. Despite this, the vaccination coverage level in most European countries is relatively low. This is largely due to patients having limited access to vaccinations. In some countries, implementing vaccinations in pharmacies and by authorized pharmacists has significantly improved vaccination coverage rates and herd immunity, while lowering the cost of treating infections and the resulting complications, as well as minimizing the phenomenon of inappropriate antibiotic therapies. This article presents the role of pharmacists in the prevention of infectious diseases, pointing out the measurable effects of engaging pharmacists in conducting preventive vaccinations, as well as analyzing the models of implementing and conducting vaccinations in pharmacies in selected countries, and depicting recommendations regarding vaccinations developed by international organizations. The presented data is used to suggest requirements for the implementation of preventive vaccinations in community pharmacies.

Readiness and Willingness to Provide Immunization Services after Pilot Vaccination Training: A Survey among Community Pharmacists Trained and Not Trained in Immunization during the COVID-19 Pandemic in Poland.

BACKGROUND: Immunization rates among the adult population in Poland are below desired targets, urging the need to expand this service in the community. During the COVID-19 pandemic, the ultimate goals for limiting the spread of the infection are vaccines against SARS-CoV-2. Pharmaceutical companies are in a race for the fastest possible way to deliver vaccines. Community pharmacists in Poland are recognised as an accessible yet underutilised group of medical professionals. Therefore, involving pharmacists in vaccinations may have beneficial results for the healthcare system. OBJECTIVES: The objectives of this study were to assess the readiness and willingness of community pharmacists following the Pharmacist Without Borders project who had either been trained or not in providing immunization services, and to identify the factors that may support the implementation of such services in Poland. METHODS: This study was conducted among pharmacists between February and August 2020 in Poland. A survey was developed to determine their readiness to provide vaccination services in their pharmacies, to recognise any barriers to vaccinations, as well as the factors necessary to implement vaccination services in Polish pharmacies. RESULTS: A total of 1777 pharmacists participated in the study, comprising 127 (7.1%) pharmacists trained in vaccinations during the Pharmacists Without Borders project and 1650 (92.9%) pharmacists not participating in the workshops. Pharmacists participating in the workshops more often indicated that providing vaccinations in community pharmacies would improve the overall vaccination rate (p = 0.0001), and that pharmacists could play an important role in advertising and promoting vaccinations (p = 0.0001). For the pharmacists not participating in the workshops, they indicated to a much greater extent possible barriers affecting the readiness to provide vaccinations in pharmacies. They most often pointed out that vaccination services would result in a significant workload increase (p = 0.0001), that pharmacies were not adapted to immunization, and that there were not enough training courses for pharmacists (p = 0.0001). CONCLUSION: The pharmacists working in community pharmacies indicated many advantages of vaccinations in pharmacies. This study identified barriers to the introduction of vaccinations and factors necessary to implement these services in pharmacies. The pharmacists trained during the immunization programme of the Pharmacists Without Borders project showed a greater readiness to provide immunization services.

Prevalence of Current and Past SARS-CoV-2 Infections among Police Employees in Poland, June-July 2020.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We aimed to determine the prevalence of current and past SARS-CoV-2 infections among police employees. METHODS: This cross-sectional survey was undertaken among 5082 police employees from Mazowieckie Province, Poland. RT-PCR testing for current SARS-CoV-2 infection and serological tests (ELISA) for the presence of anti-SARS-CoV-2 IgM+IgA and IgG antibodies were performed. RESULTS: All RT-PCR tests were negative. The anti-SARS-CoV-2 IgM+IgA index was positive (>8) in 8.9% of participants, including 11.2% women and 7.7% men (p < 0.001). Equivocal IgM+IgA index (6-8) was found in 9.8% of participants, including 11.9% women and 8.7% men (p < 0.001). The IgG index was positive (>6) in 4.3% and equivocal (4-6) in 13.2% of participants. A higher odds of positive IgM+IgA index was found in women vs. men (OR: 1.742) and police officers vs. civilian employees (OR: 1.411). Participants aged ≥60 years had a higher odds of positive IgG index vs. those aged 20-29 years (OR: 3.309). Daily vaping also increased the odds of positive IgG index (OR: 2.058). CONCLUSIONS: The majority of Polish police employees are seronegative for SARS-CoV-2 infection. Vaping and older age (≥60 years) were associated with a higher risk of SARS-CoV-2 infection.

Occupational risks for SARS-CoV-2 infection: the Polish experience.

OBJECTIVES: The disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), termed COVID-19, is asymptomatic or mild in most cases. These patients do not need treatment in hospital and can be isolated at home. To date, most studies have been conducted among inpatients with severe COVID-19. In this study, the authors surveyed patients with mild COVID-19 who remained in home isolation, and analyzed the sources and occupational risk factors for SARS-CoV-2 infections. MATERIAL AND METHODS: This cross-sectional study was carried out on April 17-18, 2020, among patients infected with SARS-CoV-2 who remained in home isolation in Poland. Data were acquired through a structured interview that included questions about the isolation course, symptoms, comorbidities, infection source, household characteristics, occupation, and workplace. Data were presented with descriptive statistics. RESULTS: Of the 4878 patients in home isolation, the authors were able to contact 3313. Of them, 1191 patients declined their invitation, and 2122 agreed to take part. The median age of the patients included in the study was 50 years; 59% were female. Most patients (92%) had not been abroad before the infection. More than half (55%) knew how they became infected; of them, 75% became infected at work. Of all patients, 70% were occupationally active. Nearly half of the occupationally active patients (48%) worked in healthcare, 3% worked in public administration or defense, 3% worked in transportation, and 2% worked in education. Sixty-five percent of the occupationally active patients worked in companies with >100 employees. CONCLUSIONS: Most of the patients with COVID-19 in home isolation in Poland were occupationally active, wherein the majority of people who were aware of the source of SARS-CoV-2 infection worked in healthcare. As most of the infected patients worked in companies with >100 employees, which is not a Polish employment pattern, the authors expect that smaller companies may have a lower risk of SARS-CoV-2 infections. Int J Occup Med Environ Health. 2020;33(6):781-9.