COVID-19 in Poland: potential associations with epidemiology, population and healthcare quality

An attempt to assess basic epidemiological data was made 2 months after confirming the first case of SARS-CoV-2 in Poland (March 4^th, 2020). The aim of the study was to examine which indicators related to epidemiology, population characteristics and health care quality affect COVID-19 incidence, mortality and case fatality in Poland.

The study was based on national data as of May 4^th, 2020. For each voivodeship incidence rates, mortality rates, case fatality rates and daily cumulative index (DCI) were calculated. The correlations were examined using Pearson's and Spearman's rank correlation coefficient, with a significance level of p < 0.05 (2-tailed tests).

The overall COVID-19 incidence rate was 3.65 per 10,000 population, mortality rate 0.18 per 10,000 population and case fatality rate 5%. All three disease indicators were positively correlated with DCI and negatively correlated with the number of hospital beds in infectious diseases wards per 10,000 population. Both incidence and mortality rates were positively correlated with population density and number of cases per COVID-19 designated hospital.

The positive correlation between DCI and both mortality and case fatality suggests that DCI could be considered as an indirect indicator of healthcare burden, compared to incidence rate alone. Our analysis confirms the role of social distancing in reducing viral transmission. The results could be useful for policymakers to plan ahead in order to relieve the risk of healthcare system overload during the current and future epidemics.