# Predictive Model of Lyme Disease Epidemic Process Using Machine Learning Approach
## 3 Materials and Methods
### Data Analysis  
In Ukraine, Lyme disease is subject to mandatory registration. A doctor who has identified a case of Lyme disease sends an emergency notification of an infectious patient to the Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine (RCDC). This document contains information about the patient, his full name, age, address, contact details, place of work and profession, date of seeking medical help, and the main symptoms of the disease when detected. The epidemiologist investigates the case and enters data into the case investigation forms focusing on infectious diseases and the cases of humans. In addition to information about the patient, information is provided on the alleged place, infection circumstances, and measures taken. Information about cases is stored in the RCDC in the form of these documents and aggregated form in annual reports on infectious diseases in each region. In the RCDC, to conduct surveillance, field studies are carried out to collect ticks, after which laboratory studies (microscopic or PCR) of ticks are carried out to assess their infection. The data used in this study are stored at the Kharkiv RCDC and are available upon request. The incidence of tick-borne infections, including Lyme disease, depends mainly on climatic-geographical and landscape zones of the area where the pathogen is circulating [58]. The territory of Ukraine is characterized by various natural zones (a zone of mixed forests,forest-steppe, steppe, mountains, etc.). The accuracy of the incidence prediction depends on the quality of the epidemiological data collected in a particular area [63]. Therefore, the study was conducted on the territory of only one region of Ukraine--Kharkiv, located in zones of forest-steppe and steppe. We have analyzed the epidemic situation using official data from the Kharkiv RCDC. The information was analyzed and included data on cases of Lyme disease, their demographic characteristics (gender, age of the sick person), place of infection, number of people seeking medical help for a tick bite, infection of ticks taken from people and collected on blanket dragging and flagging, and the number of ticks on the studied territory. In the Kharkiv region, the first case of Lyme disease was registered in 2000, and since then, epidemiological surveillance has been carried out. An epidemiological and entomological analysis from 2000 to 2015 showed that the incidence rate in the Kharkiv region exceeded those in the rest of Ukraine before 2005. Since 2006 there has been a steady increase in the incidence rate (Figure 3). In recent years, the epidemic situation with regard to Lyme disease has worsened in the Kharkiv region, and the number of cases continues to grow (from 2 cases in 2000 to 228 in 2015). During the period of epidemiological surveillance, there were 4 abrupt increases in the incidence rate in 2005, 2009, 2012, and 2015, with a gradual increase in rates over the next two to three years, except for 2014, when there was a 1.8-fold decrease in incidence compared with the previous year. In 2015, the incidence quadrupled. On the territory of Ukraine, including the Kharkiv region, the primary vector of Lyme disease pathogens is the European tick _I. ricinus_, which dominates the territory of Ukraine. In the most active natural foci of Lyme disease in Ukraine, ticks infected with Borrelia reach 10-70%. In the territory of the Kharkiv region, seven species of ixodid ticks are found, of which the most epidemiologically significant are three: _I. ricinus_ (forest tick), _Dermacentor reticulatus_ (meadow tick), and _D. marginatus_ (pasture tick). The most numerous and widespread throughout the region is I. ricinus (86% of all tick collected in natural conditions), the _D. reticulatis_ is 10%, and the _D. marginatus_ is 4%. The number of ixodid ticks in natural conditions, which depends on the development cycle and several environmental factors, ranged from 12.1 per 1 km of the route in 2001 to 1.71 in 2012.