Tick-borne encephalitis (TBE), caused by the TBE virus (TBEV), is a life-threatening disease with clinical symptoms ranging from non-specific to severe inflammation of the central nervous system. Despite TBE is a notifiable disease in Serbia since 2004, there is no active TBE surveillance program for the serologic or molecular screening of TBEV infection in humans in the country. This prospective cohort study aimed to assess the TBEV exposure among tick-infested individuals in Serbia during the year 2020. A total of 113 individuals exposed to tick bites were recruited for the study and screened for anti-TBEV antibodies using a commercial indirect fluorescent antibody test (IFA) test. Blood samples from 50 healthy donors not exposed to tick bites were included as a control group. Most of the enrolled patients reported infestations with one tick, being I. ricinus the most frequent tick found in the participants. The TBEV seroprevalence was higher (13.27%, 15 total 113) in tick-infested individuals than in healthy donors (4%, 2 total 50), although the difference was not significant. Notably, male individuals exposed to tick bites showed five times higher relative risk (RR) of being TBEV-seropositive than healthy donors of the same gender (RR= 5.1, CI = 1.6–19; p = 0.007). None of the seropositive individuals developed clinical manifestations of TBE, but the first clinical-stage of Lyme borreliosis (i.e., erythema migrans) was detected in seven of them. Potential TBEV foci were identified in rural areas, mostly in proximity or within the Fruška Gora mountain. We conclude that the Serbian population is at high risk of TBEV exposure. Further epidemiological studies should focus on potential TBEV foci identified in this study. The implementation of active surveillance for TBEV might contribute to evaluating the potential negative impact of TBE in Serbia.

The tick-borne encephalitis virus (TBEV) causes a life-threatening disease named Tick-borne encephalitis (TBE). The clinical symptoms associated with TBE range from non-specific to severe inflammation of the central nervous system and are very similar to the clinical presentation of other viral meningitis/encephalitis. In consequence, TBE is often misclassified by clinical physicians, mainly in the non-identified high-risk areas where none or only a few TBE cases have been reported. Considering this situation, we hypothesized that among persons from northern Serbia who recovered from viral meningitis or encephalitis, there would be evidence of TBEV infection. To test this hypothesis, in this observational study, we evaluated the seroreactivity against TBEV antigens in patients from northern Serbia who were hospitalized due to viral meningitis and/or viral encephalitis of unknown etiology. Three cases of seroreactivity to TBEV antigens were discovered among convalescent patients who recovered from viral meningitis and/or encephalitis and accepted to participate in the study (n = 15). The clinical and laboratory findings of these patients overlap with that of seronegative convalescent patients. Although TBE has been a notifiable disease in Serbia since 2004, there is no active TBE surveillance program for the serologic or molecular screening of TBEV infection in humans in the country. This study highlights the necessity to increase the awareness of TBE among physicians and perform active and systematic screening of TBEV antibodies among patients with viral meningitis and/or encephalitis.

Background: This study aimed to investigate the clinical form, risk factors, and outcomes of patients with COVID-19 and Clostridioides difficile co-infections. Methods: This retrospective study (2 September 2021–1 April 2022) included all patients with Clostridioides difficile infection (CDI) and COVID-19 infection who were admitted to the Covid Hospital of the University Clinical Center of Vojvodina. Results: A total of 5124 COVID-19 patients were admitted to the Covid Hospital, and 326 of them (6.36%) developed hospital-onset CDI. Of those, 326 of the CDI patients (88.65%) were older than 65 years. The median time of CDI onset was 12.88 days. Previous hospitalizations showed 69.93% of CDI patients compared to 38.81% in the non-CDI group (p = 0.029). The concomitant antibiotics exposure was higher among the CDI group versus the non-CDI group (88.65% vs. 68.42%, p = 0.037). Albumin levels were ≤ 25 g/L among 39.57% of the CDI patients and 21.71% in the non-CDI patients (p = 0.021). The clinical manifestations of CDI ranged from mild diarrhea (26.9%) to severe diarrhea (63.49%) and a complicated form of colitis (9.81%). Regarding outcomes, 79.14% of the CDI patients recovered and 20.86% had fatal outcomes in-hospital. Although a minority of the patients were in the non-CDI group, the difference in mortality rate between the CDI and non-CDI group was not statistically significant (20.86% vs. 15.13%, p = 0.097). Conclusions: Elderly patients on concomitant antibiotic treatments with hypoalbuminemia and with previous healthcare exposures were the most affected by COVID-19 and CD co-infections.

Tick-borne encephalitis (TBE) is an emerging vector-borne disease in Europe, but its epidemiology remains poorly defined in Serbia. In orthoflavivirus-endemic settings, diagnostic challenges may contribute to underrecognition of TBE, particularly among patients with suspected West Nile virus (WNV) infection. We conducted a multicenter retrospective study including patients hospitalized between 2018 and 2023 with suspected WNV neuroinvasive disease or viral encephalitis of unknown etiology. Serum samples were tested for TBEV-neutralizing antibodies using a microneutralization assay. Among 79 patients, TBEV-neutralizing antibodies were detected in four (5.1%). Most reactive cases occurred in patients initially classified as having suspected WNV-associated meningoencephalitis, while TBE had not been considered in the differential diagnosis at admission. These findings suggest that TBE may be underrecognized in Serbia and highlight the importance of confirmatory testing in orthoflavivirus-endemic settings. Strengthening clinical awareness and surveillance will be essential to better define the burden of TBE and inform prevention strategies.

Background and Objectives: Sepsis is a life-threatening organ dysfunction, and specific biomarkers could improve prognostic assessment in septic patients. The Sequential Organ Failure Assessment (SOFA) score is the standard tool for clinical sepsis monitoring. Recent studies highlight the need for its revision and the identification of rapid, specific, sensitive predictors of sepsis mortality. The aim of this study was to determine the significance of cardiac biomarkers alone or combined with the SOFA score for evaluating sepsis-related mortality. Materials and Methods: This is a retrospective, single-center study with a relatively small sample size of 73 septic patients (Sepsis-3 criteria) hospitalized in an intensive care unit (ICU) and intermediate care unit (IMCU). All patients had standard laboratory parameters, cardiac biomarkers, and the SOFA score available upon admission. Statistical analyses included non-parametric Mann–Whitney U test, ROC (Receiver Operating Characteristic) curve analysis, Hanley & McNeil method and Hosmer–Lemeshow goodness-of-fit test. Results: Lactate (p < 0.001) and SOFA (p < 0.001) showed the highest area under the curve (AUC) values, and all cardiac biomarkers had statistically significant AUCs (p < 0.05) for sepsis mortality prediction. A comparison of all ROC curves was conducted, but no statistically significant differences were observed. Adding hs-cTn (high-sensitivity cardiac troponin) and lactate to the SOFA score increased its AUC from 0.767 to 0.827 (p = 0.421). Conclusions: The results highlight the potential role of cardiac biomarkers alone or in combination with the SOFA score as useful clinical tool for predicting sepsis mortality. Further research with a larger sample size is required to validate and generalize the findings.

West Nile neuroinvasive disease (WNND) causes substantial morbidity in endemic regions, yet data on its burden in Serbia remain limited. We conducted a retrospective, population-based study of WNND cases reported in Vojvodina Province, Serbia, from 2012 to 2025. Incidence and mortality trends were analysed by year, residence, age, sex, and week of symptom onset. Multivariable logistic regression was used to identify predictors of fatal outcome. Of 1337 suspected cases, 557 (41.66%) met the WNND case definition (530 confirmed, 27 probable cases) and 98.9% were autochthonous. The mean annual incidence was 2.17/100,000 (95% CI 0.60–3.75), ranging from 0.48/100,000 (2015) to 10.31/100,000 (2018), with additional peaks in 2013 and 2022. Cases clustered predominantly in epidemiological weeks 31–34. The mean mortality was 0.28/100,000 (95% CI 0.02–0.53) and the mean case fatality rate was 12.93% (95% CI 10.14–15.71%). Incidence increased with age, peaking at 5.97/100,000 in those 70–79 years; highest mortality occurred in ≥80 years (1.78/100,000). All districts reported cases, with the highest incidence and mortality in South Banat. Higher Charlson Comorbidity Index, cardiovascular disease, diabetes and malignancy independently predicted fatal outcome. WNND remains a significant public health problem in Vojvodina, requiring improved surveillance, targeted prevention, and early treatment of high-risk patients.