In recent years, the prevalence of tick-borne bacterial diseases has significantly increased in European countries. The emergence and reemergence of these illnesses are attributed to changes in the environment and human behavior. Several diseases are caused by bacteria initially isolated from ticks and subsequently considered pathogenic. It is necessary to consider the bacteria found in arthropods capable of biting humans as potential human pathogens. Here we review the clinical and epidemiological data on bacterial tick-borne diseases in European countries. We focus on the epidemiological and clinical aspects of tick-borne rickettsioses and give an overview of other tick-borne illnesses as well as the emergence and re-emergence of these diseases.

BACKGROUND: It has been observed that Muslim pilgrims departing France for Mecca have low national immunization rates against tetanus, diphtheria and poliomyelitis (TdP). Our purpose is to identify immigration, socio-economic and socio-cultural determinants of vaccination coverage against TdP. METHODS: A cross-sectional survey study was conducted in late 2006 among 580 pilgrims in preparation who attended the Infectious and Tropical Medicine ward in Hôpital Nord at Marseille to receive their N. meningitidis vaccine required for travel to Mecca. RESULTS: Total vaccination rates for tetanus (18.9%), diphtheria (14.7%) and poliomyelitis (15.0%) were comparable. Pilgrim's characteristic lower socio-economic and social status, in addition to their unifying linguistic, cultural and religious identity defines them as a particularly disadvantageous group in France. French citizenship, higher level of education, better French fluency and no previous travel to country of origin were the strongest and most significant determinants of TdP vaccination status. CONCLUSION: These results suggest that the Muslim community in France is at risk from inequities of national preventive care efforts.

Background. The majority of published studies on Hajj-related diseases were based on hospitalized patient cohorts. Methods. A total of 545 Hajj pilgrims from Marseille were enrolled in a prospective epidemiological study to evaluate the incidence of common health hazards. They were administered a questionnaire before traveling addressing demographic factors and health status indicators and a post-travel questionnaire about travel-associated diseases. Results. Respondents had a median age of 61 years and originated mainly from North Africa (81%). A significant proportion of individuals had chronic medical disorders such as walking disability (26%), diabetes mellitus (21%), and hypertension (21%). A total of 462 pilgrims were administered a questionnaire on returning home. A proportion of 59% of travelers presented at least one health problem during the pilgrimage and 44% of the cohort attended a doctor during travel; 3% were hospitalized. Cough was the main complaint among travelers (attack rate of 51%), followed by headache, heat stress, and fever. Few travelers suffered diarrhea and vomiting. Cardiovascular diseases, neurological disorders, trauma, skin and gastrointestinal problems were not frequently observed in our survey, suggesting that their prevalence among the causes of admission to Saudi hospitals reflects a bias of selection. Cough episodes were significantly more frequent in individuals >55 years. We also evidenced that women were more likely to present underlying chronic cardiovascular disorder and diabetes compared to men and that they more frequently suffered from cough episodes associated with fever during the Hajj. Conclusions. Health risks associated with the Hajj in our experience are much more related to crowding conditions than to travel. Our work suggests that the studies performed in Saudi specialized units probably overestimate the part of certain diseases within the spectrum of Hajj-associated diseases. Our results also suggest that old female Hajjes should be considered as a high-risk population and that preventive measures should be reinforced before departing for Saudi Arabia.

We investigated epidemiologic and clinical aspects of rickettsial diseases in 280 international travelers reported to the GeoSentinel surveillance Network during 1996-2008. Of these 280 travelers, 231 (82.5%) had spotted fever (SFG) rickettsiosis, 16 (5.7%) scrub typhus, 11 (3.9%) Q fever, 10 (3.6%) typhus group (TG) rickettsiosis, 7 (2.5%) bartonellosis, 4 (1.4%) indeterminable SFG/TG rickettsiosis, and 1 (0.4%) human granulocytic anaplasmosis. One hundred ninety-seven (87.6%) SFG rickettsiosis cases were acquired in sub-Saharan Africa and were associated with higher age, male gender, travel to southern Africa, late summer season travel, and travel for tourism. More than 90% of patients with rickettsial disease were treated with doxycycline, 43 (15.4%) were hospitalized, and 4 had a complicated course, including 1 fatal case of scrub typhus encephalitis acquired in Thailand.

We analyzed prospective data on 17,228 European patients who sought treatment at GeoSentinel sites from 1997 to 2007. Gastrointestinal illness (particularly in tourists), fever (those visiting friends and relatives [VFRs]), and skin disorders (in tourists) were the most common reasons for seeking medical care. Diagnoses varied by country of origin, region visited, or categories of travelers. VFRs who returned from sub-Saharan Africa and Indian Ocean islands were more likely to experience falciparum malaria than any other group. Multiple correspondence analysis identified Italian, French, and Swiss VFRs and expatriate travelers to sub-Saharan Africa and Indian Ocean Islands as most likely to exhibit febrile illnesses. German tourists to Southeast and south-central Asia were most likely to seek treatment for acute diarrhea. Non-European travelers (12,663 patients from other industrialized countries) were less likely to acquire certain travel-associated infectious diseases. These results should be considered in the practice of travel medicine and development of health recommendations for European travelers.

Ehrlichioses and anaplasmoses are caused by alpha-proteobacteria within the family of Anaplasmataceae. These diseases have been known for a long time in veterinary medicine and recently in human medicine. These tick-borne zoonoses are considered as emerging diseases. The first case of human monocytotropic ehrlichiosis occurred in 1986. Human granulocytic anaplasmosis was described as a separate entity in 1994 and ehrlichiosis caused by Ehrlichia ewingii was reported in humans in 1999. The number of cases has been rising steadily due to better diagnostic techniques and better surveillance worldwide. In this review, we will present human and animal ehrlichioses and anaplasmoses as emerging diseases and present candidate(s) for the future.