In the present study, we aimed to assess the anti-SARS-CoV-2 antibodies in population or in convalescents 6 months after infection with COVID-19. The study population consisted of 2 groups, i.e. group I: 232 post-COVID-19 patients, and group II: 544 patients from a population cohort. Detection of anti-N antibodies was performed with Elecsys Anti-SARS-CoV-2 and anti-S antibodies with LIAISON SARS-CoV-2 S1/S2 IgG tests. After the Omicron wave, gradual increase in the prevalence of the analyzed antibodies was observed in the general population - up to 92.5% of anti-S and 69.7% of anti-N antibodies. In the COVID-19 convalescents, 6 months after infection, 4.3% and 3.7% did not generate significant titer of anti-S and anti-N antibodies, respectively. Among patients, who were vaccinated, 1% did not generate anti-S antibodies. Median age of those who did not respond was higher than those who responded. Sex did not influence the results. Comparison of anti-N and anti-S antibodies 6 months after infection in the whole group showed higher anti-N titer in patients who suffered from the disease than in the general population. In the general population, 17.4% of participants had anti-N antibodies, and 9% had anti-S antibodies, despite no prior vaccination or history of COVID-19. High prevalence of anti-N antibodies in patients reporting no history of COVID-19 during last wave, even after official end of the pandemics suggests high prevalence of SARS-CoV-2 in the environment and frequent asymptomatic or unspecific COVID-19, what is of high importance from the public health perspective.

The coronavirus disease 2019 pandemic created a significant crisis in global health. The aim of the study was to compare the impact of the COVID-19 pandemic on self-rated health status and smoking and alcohol habits. The Bialystok PLUS cohort study was conducted in 2018–2022. A total of 1222 randomly selected city residents were examined and divided into two groups: before and during the COVID-19 pandemic. The participants’ lifestyle habits and medical history were collected from self-reported questionnaires. The Alcohol Use Disorders Identification Test (AUDIT) and the Fagerström Test for Nicotine Dependence (FTND) were used to assess the degree of alcohol and nicotine dependence. The survey revealed a reduced frequency of reported allergies vs. an increased frequency of reported sinusitis and asthma; increased incidence of declared hypercholesterolemia and visual impairment; a reduced number of cigarettes smoked per day, lower FTND score, and a greater desire to quit smoking in the next six months; and an increase in hs-CRP and FeNO levels in the population during the pandemic compared to the pre-pandemic population. The COVID-19 pandemic had a measurable impact on the general population’s prevalence of certain medical conditions and lifestyle habits. Further research should continue to examine the long-term health implications of the pandemic.

Tick-borne encephalitis (TBE) is the most prevalent viral infection of the central nervous system (CNS) in Poland. The disease is characterized by the presence of two stages. The first phase, called the viremic stage, presents with flu-like symptoms, while the second stage of TBE is characterized by damage to the nervous system and may follow a severe and dramatic course. The aim of this paper is to increase the awareness of the potential sequelae after TBE. In this study, we report cases of severe TBE in 36-year-old and 57-year-old female patients. The outcome of TBE varies from patient to patient, but there are some factors that can help to predict the severity of TBE infection. The risk factors presented in these patients were as follows: the monophasic course of TBE, high pleocytosis in cerebrospinal fluid (CSF) and older age. Both of our patients were not vaccinated despite the World Health Organization’s (WHO’s) recommendations. Both patients had no history of travel outside their region of residence prior to the onset of illness. The few risk factors shown in our patients and the serious sequelae of the disease may indicate the need to test patients for possible gene mutations.