Unexplained Fever In Infectious Diseases: Section 2: Commonly Encountered Aerobic, Facultative Anaerobic, And Strict Anaerobic Bacteria, Spirochetes, And Parasites
Benedict Isaac, Serge Kernbaum, Michael Burke in Unexplained Fever, 2019
Bartonellosis (syn. Carrion’s disease) is caused by a small, motile aerobic Gram-negative bacillus, Bartonella bacilliformis. The disease is endemic in Peru, Ecuador, and Colombia. The organism invades the erythrocytes and reticuloendothelial cells. Various species of the sandfly vector, Phlebotomus, transmit the infection. There are two clinical forms: febrile (Oroya fever) and cutaneous (Verruga peruana). The former deserves a short mention because it may create problems of unexplained fever. After an incubation of approximately 20 days, or more, may appear a fever with shacking chills, malaise, headache, arthralgias, myalgias, changes in mentation, adenopathies, and severe anemia. Some critical forms may develop dyspnea, delirium, coma, and death. Intercurrent infections are common, especially salmonellosis, which may account for the prolongation of fever and adversely affect the prognosis. During the acute febrile stage, the organism may be identified on Giemsa-stained smears of the peripheral blood or by blood culture.80
Flies (Biting)
Gail Miriam Moraru, Jerome Goddard in The Goddard Guide to Arthropods of Medical Importance, Seventh Edition, 2019
Female sand flies are blood feeders; males are not, but they will suck moisture from available sources. Despite their medical importance, much of what is known about sand flies is speculative or based on limited field observations. Sand flies are usually found in microhabitats within larger biological communities. Examples of these microhabitats are caves, cavities, tree holes, burrows, pit latrines, animal enclosures, and other buildings. Breeding is believed to take place in these areas, and feeding on hosts occurs there or in close vicinity. Sand flies in the genus Brumptomyia feed on armadillos, whereas Lutzomyia spp. feed on both mammals and reptiles. Members of the genus Sergentomyia feed on reptiles and amphibians. Phlebotomus spp. are exclusively mammal feeders. Sand flies are generally active at night when there is little or no wind, but a few species may feed during the day if disturbed or under cloudy or shaded conditions. They normally rest during the day in their microhabitats. Sand fly development is relatively slow, taking up to several months to complete the life cycle. P. papatasi, the primary vector of leishmaniasis in the Middle East region, is a nocturnal, desert species flying from sunset through dark. It enters dwellings from animal burrows up to 50 meters away. Its activity diminishes rapidly when relative humidity falls below 65%, temperature rises above 80°F, or wind velocity exceeds 5 miles per hour.
Vectors and Reservoir Hosts
Yamuna Deepani Siriwardana in Leishmaniasis in Sri Lanka, 2023
Many morphological and genetic-based studies on sandfly taxonomy have been carried out in Sri Lanka. With the recent emergence (or recent discovery) of cutaneous leishmaniasis in the country, local scientists have undertaken further studies on sandfly vectors. First, such a report on attempts toward morphological characterization of Phlebotomus argentipes was published in 2005 (Surendran et al., 2005). Authors were able to collect the flies using human traps and further proved the anthropophagic nature of the sandflies in Northern Sri Lanka and in Southern Sri Lanka (in Delft islands and Moneragala, respectively).
The management of Babesia, amoeba and other zoonotic diseases provoked by protozoa
Published in Expert Opinion on Therapeutic Patents, 2023
Clemente Capasso, Claudiu T. Supuran
Leishmania spp. have straightforward life cycles that require a mammalian host and a vector stage. Phlebotomine sandflies spread the parasite Leishmania in the Americas, while the genus Phlebotomus is involved in the other parts of the world [121]. Sandflies become infected by feeding on hosts with active skin lesions of cutaneous leishmaniasis or with high parasitemia in the case of visceral leishmaniasis. Parasites become promastigotes in the sandfly midgut and multiply in 4–14 days [121]. These promastigotes travel to the salivary glands, become infectious metacyclic promastigotes, and await feeding. Sandflies inject infective promastigotes into susceptible mammals during eating. Resident phagocytes phagocytize promastigotes, which become tissue-stage amastigotes and divide in a parasitophorous vacuole. The amastigotes impede phagosome acidification, allowing them to persist within phagocytes. Depending on host and parasite parameters, the parasite infects more phagocytic cells at the site of cutaneous infection or in secondary lymphoid organs, causing parasitemia [121]. Leishmania species can stay hidden from the host immune system for years using their own special set of virulence mechanisms. Preventing the spread of the disease via sandflies is a top priority. Transmission can be considerably reduced if people stay inside between dark and dawn when sandflies are most active [122]. Topical insect repellents, bed nets, and clothing coated with permethrin are also efficient at keeping sandflies at bay. Residual household sprays have been used to minimize the prevalence of vectors in residential areas [122].
Epidemiological and clinical features of visceral leishmaniasis in children in Alicante Province, Spain
Published in Paediatrics and International Child Health, 2018
Jose M. Ramos, Agustin Clavijo, Luis Moral, Cesar Gavilan, Tatiana Salvador, Javier González de Dios
Leishmaniasis is caused by the protozoan pathogen genus Leishmania. There are three major clinical forms: cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis and visceral leishmaniasis (VL). Although the disease is endemic in 98 countries, more than 90% of cases occur in just six countries: India, Bangladesh, Sudan, South Sudan, Ethiopia and Brazil [1]. Georgia, Spain, Albania, Italy, Turkey, Tajikistan and Azerbaijan are the most commonly affected countries in the World Health Organization (WHO) European Region [1]. The Mediterranean region contributes only to 5–6% of the global burden of VL, which in Spain is hypo-endemic and caused by the protozoan Leishmania infantum [1]. The parasite is transmitted by the bite of an infected female sandfly of the phlebotomus genus (mainly Phlebotomus perniciosus) and is maintained in a zoonotic cycle, with dogs being the main reservoir [1–4].
The enemy at home: leishmaniasis in the Mediterranean basin, Italy on the focus
Published in Expert Review of Anti-infective Therapy, 2020
Elena Gianchecchi, Emanuele Montomoli
More than 54 species belong to the genus Leishmania, 21 of them with critical medical importance [1]. Leishmania complex digenetic life cycle includes a susceptible vertebrate host and a permissive insect vector. Specifically, (human) pathogenic species of Leishmania are spread by the bite of different female sandflies [2], Phlebotomus (P.) spp. and Lutzomyia spp. in the Old (Southern Europe, Mediterranean basin, Middle East, Asia, and Africa) and New World (Central and South America), respectively. The parasite populates in all continents, involving also Oceania [3], a continent thought to be free of Leishmania until recent years upon the identification of cutaneous leishmaniasis (CL) in native Australian macropods [4].
Related Knowledge Centers
- Ddt
- Leishmania
- Leishmania Donovani
- Leishmaniasis
- Malaria
- Parasitism
- Visceral Leishmaniasis
- Lutzomyia
- Canine Leishmaniasis
- Disease Vector