Lyme boreliosis and tick-borne meningoencephalitis are a natural focal infections whose common vector is hard tick Ixodes ricinus but is also a main reservoir of the disease. Lyme boreliosis is a systemic disease also known as lyme disease, which is caused by the pathogen od the Borrelia burgdorferi, and is also characterized by skin changes and erythema chronicum migrans with general symptoms but in more severe cases it is possible to develop neurological complications. Tick-borne meningoencefalitis is a viral disease caused by RNA virus of the genus Flavivirus and is counted in arbovirus infections that occur exclusively in natural hotspots. There are three subtypes of the virus according to geographical distribution, tick vector, phatogenicity for humans and by clinical manifestation of infection, and the most significant subtype of the virus in Europe is the European type of virus who is manifested by symptoms of central nervous system dysfunction. Due to common vector of the disease, i.e. the tick Ixodes ricinus, there is a possibility of co-infection with both agents of the disease, which is a clinical and epidemiological problem due to various treatment therapies and may ultimatly result in a longer recovery period and in some cases death. Therefore, in terms of prevention for both diseases it is recommended to use adequate clothing and footwear when going to endemic areas of the disease and also impregnate clothing with repellents if is necessary. The vaccine for Lyme boreliosis does not exist, while for tick-borne meningoencephalitis is recommended to be vaccinated for people who are belonging to risk groups, who go professionally into the forests and people who are living in endemic hotspots of ticks Ixodes ricinus. In the area of the City of Zagreb in the period between 2014. and 2018. there were reported 824 people suffered from Lyme boreliosis, while 2 people where suffered from tick-borne meningoencephalitis in the same period. It is determined that from Lyme boreliosis is more likely to be sickened by woman with a share of 56,7% and males with a share of 43,3%. In year of 2014. there was reported one male person suffered from tick-borne meningoencephalitis and in year of 2015. was reported one female suffered from the same disease. Age-related analysis shows the highest number of Lyme boreliosis patients in people over 60 years of age, while tick-borne meningoencephalitis is one person in the 5 to 8 year old age group and the other person from 30 to 39 years of age. Analysis by application date shows that the highest number of reports are in months of May and June and the lowest number of reports are in months of December and January. Comparing the number of Lyme boreliosis patients in period from year of 2014. to 2018. between the City of Zagreb and Republic of Croatia it was determined that the highest number of patients was in year of 2018. were has been reported 820 cases in Republic of Croatia of which 292 cases were reported in the City of Zagreb which is 35,4% of the total number of applications. For tick-borne meningoencephalitis in period from year of 2014. to 2018. were much less reported cases in the City of Zagreb who is counting 2 infected people and Republic of Croatia who is counting 88 people.