Epidemiological characteristics of COVID-19 travel-associated cases in Vojvodina, Serbia, during 2020.

Coronavirus disease 2019 (COVID-19) is currently the biggest public health problem worldwide. Intensive international travel and tourism have greatly contributed to its rapid global spreading. This study is the first comprehensive analysis of the epidemiological characteristics and clinical outcomes of the travel-associated COVID-19 cases in Vojvodina, Serbia, from March 6 to December 31, 2020 and it concerns permanent residents of Serbia. A cross-sectional study was conducted using data from the dedicated surveillance database of the Institute of Public Health of Vojvodina. Overall, 650 travel-associated COVID-19 cases were recorded in Vojvodina during the observed period, mainly imported from Bosnia and Herzegovina, followed by Austria and Germany (N = 195, 30%; N = 79, 12.15% and N = 75, 11.54%, respectively). The majority of cases were in the working-age groups, 18-44 and 45-64 years (56.46% and 34.15%, respectively). Overall, 54 (8.31%) patients developed pneumonia. In comparison to patients without pneumonia, those with pneumonia were older (mean age = 55.39 years vs. 41.34 years, p<0.01) and had a higher percentage of comorbidities (57.41% vs. 16.61%). Men were more likely to develop pneumonia than women (OR = 2.22; 95% CI: 1.14-4.30, p = 0.02), as well as those in retired-age group (OR = 4.11; 95% CI: 2.0-8.46, p<0.01). Obesity (OR = 14.40; 95% CI: 3.8-54.6, p<0.01), diabetes (OR = 9.82; 95% CI: 3.15-30.61, p<0.01) and hypertension (OR = 7.99; 95% CI: 3.98-16.02, p<0.01) were the most prominent main comorbidities as predictors of pneumonia. Our results represent general epidemiological and clinical dynamics of COVID-19 disease in Vojvodina. Also, they provide evidence that the predictors of pneumonia were: increasing age, male sex, having underlying comorbidities, an increasing number of days from the return to laboratory confirmation of COVID-19 (OR = 1.08, 95% CI: 1.03-1.12, p<0.01), as well as an increasing number of days from symptoms onset to diagnosis (OR = 1.14, 95% CI: 1.07-1.21, p<0.01), while anosmia and ageusia were protective factors for developing it (OR = 0.31, 95% CI: 0.12-0.79, p = 0.01).