Infectious diseases in Poland in 2022

OBJECTIVES. We summarize the epidemiological situation of infectious diseases in 2022 in Poland, with particular attention to the potential impact of the COVID-19 pandemic and the influx of refugees from Ukraine, which occurred as a result of Russian aggression against this country. MATERIAL AND METHODS. The evaluation uses published surveillance reports for individual diseases (Epidemiological chronicle) and data from the national register of infectious diseases Epibaza, which collects mandatory reports and information obtained during epidemiological investigations conducted by the State Sanitary Inspection. Data on mortality were obtained from Statistics Poland. RESULTS. In 2022, 2,370,351 cases of COVID-19 and 29,026 deaths due to this disease were recorded. COVID-19 mortality in 2022 was significantly lower (by 68%) than in 2021, although COVID-19 still caused more deaths than other infectious diseases combined. In 2022, mass testing for SARS-CoV-2 was withdrawn, causing much higher incidence underestimation. For diseases such as influenza and influenza-like illnesses, chickenpox, Lyme disease, the 2022 incidence corresponded to the median for the years 2016-2020. The incidence of tick-borne encephalitis (+70.8% vs. 2016-2020 median), Clostridioides difficile infections (+93.5% vs. 2016-2020 median), norovirus infections (+62.8% vs. 2016-2020 median), invasive pneumococcal disease (+88.8% vs. 2016-2020 median), and sexually transmitted infections returned to the upward trend. In the case of HIV, diagnoses among migrants from Ukraine also contributed to the increased number of new diagnoses (+100.9%). Migrants from Ukraine accounted for the highest percentage of HIV/AIDS cases (23.9%), hepatitis B (6.2%) and C (10.6%), tuberculosis (4.6%), measles (11.1%), and rubella (4.8%). The size of the Ukrainian migrant population in Poland is estimated at 2%-3% of the general population. CONCLUSIONS. For most diseases, there was an increase in recorded incidence compared to 2020-2021 and a return to pre-pandemic trends. The impact of the influx of refugees from Ukraine was small for most diseases.