Ticks and Tickborne Bacterial Diseases in Humans: An Emerging Infectious Threat

Abstract

Ticks are currently considered to be second only to mosquitoes as vectors of human infectious diseases in the world. Each tick species has preferred environmental conditions and biotopes that determine the geographic distribution of the ticks and, consequently, the risk areas for tickborne diseases. This is particularly the case when ticks are vectors and reservoirs of the pathogens. Since the identification of Borrelia burgdorferi as the agent of Lyme disease in 1982, 15 ixodid-borne bacterial pathogens have been described throughout the world, including 8 rickettsiae, 3 ehrlichiae, and 4 species of the Borrelia burgdorferi complex. This article reviews and illustrate various aspects of the biology of ticks and the tickborne bacterial diseases (rickettsioses, ehrlichioses, Lyme disease, relapsing fever borrelioses, tularemia, Q fever), particularly those regarded as emerging diseases. Methods are described for the detection and isolation of bacteria from ticks and advice is given on how tick bites may be prevented and how clinicians should deal with patients who have been bitten by ticks.

Risk of acquiring tick-borne infections in forestry workers from Lazio, Italy

“…It may cause skin, joint, neurological, ocular and cardiac disorders. Since forests and woods are the preferred ecosystem for maintenance of LB [1], the risk of contracting LB is greater in forestry workers, farmers, and other workers in wooded areas [2,3] which can acquire LB from infected ticks taking a blood meal. Sero-epidemiological studies suggest that LB and TBE infections are more prevalent among people exposed to tick bites, such as forestry workers [4].…”

Broad-range PCR-TTGE for the first-line detection of bacterial pathogen DNA in ticks

“…Many tick-borne bacteria are considered as emerging pathogens [16] such as Borrelia burgdorferi lato sensu (sl), the agent of Lyme borreliosis, the most significant human tick-borne disease in the Northern Hemisphere, and Anaplasma phagocytophilum, the agent of animal and human anaplasmosis and spotted fever group Rickettsia spp.…”

“…(SFG) [4,16,20,21]. A single tick may transmit multiple pathogens [1,9,16] but little is known about the co-infection frequency between bacteria infecting ticks [1,16].…”

Acarine ectoparasites of Panti Forest Reserve in Johore, Malaysia

“…As part of the nation's preparedness for emerging and re-emerging infections, there is a need to document information of pathogens in local ticks and mites (acarines). Acarines have been used as epidemiological tools to detect the presence of a pathogen in a specific area [16] . In Malaysia, investigations of pathogens in local ticks and chiggers have only been recently initiated.…”