Epidemiology and diagnosis of infections caused by rickettsia
Diseases Transmitted by Ticks, NOVA Publications , ss.171-183, 2021
- Yayın Türü: Kitapta Bölüm / Araştırma Kitabı
- Basım Tarihi: 2021
- Yayınevi: NOVA Publications
- Sayfa Sayıları: ss.171-183
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Rickettsial infections are among the oldest diseases known to humans and caused by members of the Rickettsiaceae family. Despite resembling other gram-negative bacteria morphologically and biochemically, the species of the family consisting of the genera Rickettsia and Orientia are obligate intracellular parasites not stained with Gram stain. Rickettsiae need a vector to infect the host. Although mostly ticks are the vectors, which also serve as reservoirs, some of the rickettsial infections are associated with fleas, lice, or mites. Rickettsiae are transmitted to humans via the bites or feces of infected arthropods. Humans are random hosts, except for R. prowazekii. Human-to-human transmission through blood transfusion and organ transplantation has been reported. Over the last 30 years, many species of rickettsia have been identified with the development of molecular techniques such as multilocus sequence typing (MLST) or next-generation sequencing. The incidence pattern of rickettsial diseases follows the activity periods of the vectors. Rickettsial organisms are widespread on all continents apart from Antarctica. Reports have been published recently, warning that global warming facilitates the transmission of some vector-borne infectious diseases. However, the role of the increase in international travel and migrations and other variables in importing parasites and vectors should not be overlooked. Rickettsioses are bacterial diseases with a clinical spectrum ranging from common tick, flea or mite-induced mild febrile illnesses to lifethreatening complications. The diagnosis of rickettsial infections brings about challenges for both clinicians and laboratory professionals. Laboratory confirmation of the infection is also highly important for understanding the epidemiology of rickettsioses and their effect on public health. Among the diagnostic methods, there are serological tests, molecular tests, culture, immunohistochemistry, and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF).