Difficulties in differential diagnosis in comorbid patients with tick-borne encephalitis

Tick-borne encephalitis (TBE) is a natural focal disease that is widespread in the Arkhangelsk Region. Of the 25 administrative territories of the Arkhangelsk Region, 20 are endemic for this disease. Moreover, according to Rospotrebnadzor data for 2023, more than 6,200 complaints about tick bites were registered in the Arkhangelsk Region, and 42 cases of tick-borne encephalitis were detected in the laboratory, which indicates a high incidence. The purpose of this work is to describe a case of a non-focal form of tick-borne encephalitis in the Arkhangelsk Region with carrying out differential diagnosis. When studying this topic, various research methods were used, including analysis of scientific literature posted in the scientific electronic libraries eLibrary, PubMed, and CyberLeninka. The article discusses the sources of TBE infection, the epidemic significance of ticks in the spread of tick-borne encephalitis virus, features of the spread of infection, as well as diagnostic criteria. The main topic is the differential diagnosis of TBE. The authors emphasize the importance of prevention, early diagnosis, and timely treatment, since TBE can cause serious complications as the disease becomes chronic. As an example of diagnostic problems, a clinical case was analyzed: the life history, epidemiological anamnesis, and clinical research data were studied. Timely suspicion of tick-borne encephalitis was prevented by an insufficiently collected epidemiological history during the patient’s initial request for medical help. The authors call for more attention to be paid to vaccine prevention of the disease and more careful collecting of epidemiological anamnesis from patients.