ABO and Rh blood groups, demographics, and comorbidities in COVID-19 related deaths: A retrospective study in Split-Dalmatia County, Croatia.

BACKGROUND: Blood group phenotypes have been associated with COVID-19 susceptibility and severity. This study aimed to examine ABO/Rh blood group distribution in COVID-19-related deaths considering demographics and pathological conditions. METHODS: We conducted a retrospective study at the University Hospital Center Split, Croatia, that included 245 COVID-19 positive individuals that died from April 8, 2020, to January 25, 2021. We extracted data on their blood groups, demographics, and pre-existing comorbidities and compared findings with general population data from blood group donations (n = 101,357) and non-COVID-19 deaths from 2019 (n = 4968). RESULTS: The proportion of dead males was significantly higher than in non-COVID-19 cases (63.7% vs. 48.9%, P < 0.001), while the proportion of older individuals did not differ. The prevailing pre-existing diseases were hypertension (59.6%), diabetes (37.1%), heart failure (28.8%), digestive disorder (26.5%), and solid tumor (21.6%). The ABO distribution in the deceased and donors' group showed significant differences, with the higher prevalence of A/AB group and lower prevalence of 0, but with individual differences significant only for AB and non-AB groups. There was a reduced proportion of females within the deceased with group 0 (P = 0.014) and a higher proportion of AB individuals with coronary heart disease (P = 0.024). CONCLUSION: The study confirmed a higher risk of death in males. The lower proportion of type 0 in deceased individuals was greater in females, implying that group 0 is not necessarily an independent protective factor. Coronary heart disease was identified as a potential risk factor for AB individuals.

BUILDING THE COVID-19 TESTING CAPACITIES IN CROATIA: ESTABLISHING THE INTERDEPARTMENTAL COVID-19 UNIT AT THE SPLIT UNIVERSITY HOSPITAL CENTRE.

This paper presents the chronology, experiences, and challenges in introducing COVID-19 RT-PCR testing in Split, Croatia. We describe the processes from March 12, 2020 to May 26, 2020, starting from the initial knowledge transfer, expert team formation and management, testing implementation, and concluding with the standalone testing facilities, which used automated processes sufficient to meet testing requirements at that time. In the case presented, the COVID-19 unit was organized by joining human and laboratory resources from five clinical departments at the Split University Hospital Centre. Sample preparation procedures and analyses were launched within the restricted time frame while simultaneously training and organizing new laboratory staff and completing equipment requirements. As a result, the process that started with 30 tests per day was constantly improved over time and reached up to 160 tests per day when MagNA Pure was added to automatize RNA extraction at the end of April. At that pace, the cumulative number of samples soon exceeded the first thousand, and by the end of May it exceeded 4000. The case presented provides an example of good practice for crisis response and organization that successfully enabled sufficient COVID-19 testing capacities within the restricted time frame, human and technical resources. Despite limited understanding of COVID-19 at that time, appropriate management, transfer of knowledge, previous experiences in related laboratory and diagnostic work, as well as interdisciplinary and interdepartmental cooperation proved appropriate to overcome the above limitations and ensure adequate healthcare response.

SARS-CoV-2 Antibody Seroprevalence in Industry Workers in Split-Dalmatia and Sibenik-Knin County, Croatia.

OBJECTIVES: To examine seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in industry workers population sample. METHODS: From 23 to April 28, 2020, we conducted serological testing for antibodies (Immunoglobulin G (IgG) and Immunoglobulin M (IgM)) on 1494 factory employees living in the Split-Dalmatia and Sibenik-Knin County (Croatia). RESULTS: We detected antibodies in 1.27% of participants (95% confidence interval [CI] 0.77-1.98%). In Split facility 13/1316 (0.99%, 95% CI 0.53-1.68%) of participants were tested positive, of which 13/1079 (1.20%, 95% CI 0.64-2.05%) of those living outside the facility and 0/237 (0%, 95% CI 0-1.26%) of those living inside the facility. In Knin facility, 6/178 (3.37%, 95% CI 1.25-7.19%) participants were tested positive for antibodies. CONCLUSIONS: The study showed relatively small SARS-CoV-2 antibody seroprevalence in the DIV Group population sample.