China
Africa
Explore chapters and articles related to this topic
Severe Influenza Pneumonia and Its Mimics in the Critical Care Unit
Published in Cheston B. Cunha, Burke A. Cunha, Infectious Diseases and Antimicrobial Stewardship in Critical Care Medicine, 2020
Specifically, dengue virus has a huge dynamic with multiple manifestations, from flu-like illnesses with headache, retro-orbital eye pain arthralgia, myalgia, and leukopenia to severe organ (liver, heart, and central nervous system) impairment and bleeding. Persistent vomiting, abdominal pain, and mucosal bleeding are important warning symptoms. The biphasic pattern of the fever, the truncal rash, and the elevated serum ferritin are key findings [38]. Typhoidal tularemia resulting from Francisella tularensis is characterized by productive cough, pleuritic chest pain, dyspnea, prostration, and frequently gastrointestinal symptoms. Typhoidal and pneumonic tularemia are the most likely forms to lead to sepsis and multi-organ failure [40].
Host-Parasite Interactions With Macrophages In Culture
Published in Hans H. Gadebusch, Phagocytes and Cellular Immunity, 2020
Lee S. F. Soderberg, Morris Solotorovsky
Francisella tularensis, another facultative intracellular parasite, has also been useful since strains of differing virulence are available. Thorpe and Marcus51 investigated three strains of F. tularensis differing by more than 10,000-fold in LDS0, mixed with uninduced peritoneal macrophages from normal rabbits. Conditions were adjusted to produce an average parasitization of five organisms per macrophage and viability counts were determined daily for 3 days. The avirulent organisms were killed within 48 hr. Organisms of intermediate virulence persisted longer but were reduced to 10% of the original inoculum at 72 hr. Virulent organisms remained relatively stationary in number for 36 to 48 hr and then increased to approximately tenfold.
Unexplained Fever In Infectious Diseases: Section 2: Commonly Encountered Aerobic, Facultative Anaerobic, And Strict Anaerobic Bacteria, Spirochetes, And Parasites
Published in Benedict Isaac, Serge Kernbaum, Michael Burke, Unexplained Fever, 2019
Tularemia is a rare infection caused by a Gram-negative coccobacillus, Francisella tularensis. It is characterized by high fever and severe constitutional symptoms that may persist for weeks to several months, if not treated appropriately. There are four clinical types: the most frequent, ulceroglandular, comprises over 80% of cases; the remainder being the glandular, oculoglandular and typhoidal forms. Problems of unexplained fever may arise in the typhoidal and ulceroglandular forms: the former, because the disease may be manifested only by fever without a primary lesion; the latter, because the primary lesion at the site of infection (papule, ulceration of the skin or mucous membrane) may be overlooked. In these two forms, the clinical and the differential diagnosis may be very difficult. The onset occurs suddenly 3 to 7 days after the infective contact, with high fever, chills, headache, nausea, vomiting, drenching sweats, severe prostration, regional lymph nodes, and splenomegaly.
The clinical impact of implementing GenMark ePlex blood culture panels for around-the-clock blood culture identification; a prospective observational study
Published in Infectious Diseases, 2020
Anders Krifors, Gunilla Rådberg, Sultan Golbob, Zhino Omar, Camilla Svensson, Daniel Heimer, Christina Carlander
The choice of the panel (BCID-GP or BCID-GN) was based on Methylene blue stain microscopy identification of cocci or rods . Methylene blue stain was chosen over Gram stain as it is easier to learn and faster to perform. Detection of a pan Gram positive or pan Gram negative target resulted in sequential testing of both panels. The fungal panel was not used. The regular laboratory biomedical analysts conducted all analyses as per the manufacturer’s instructions and within 1 h of indication of microbial growth. All preparations were conducted in a Class II biosafety cabinet. A time limit for the aerobic blood culture positivity was set to 72 h to avoid the risk of Brucella sp. or Francisella tularensis in the sample. No additional personnel were employed during the study period. At 7 am, all positive blood cultures were transported to the microbiology laboratory for culture-based identification, MALDI-TOF MS, and antibiotic susceptibility testing (AST).
Prevalence of Anaplasma phagocytophilum in humans in Belgium for the period 2013–2016.
Published in Acta Clinica Belgica, 2019
Mony Hing, Dorien Van Den Bossche, Tinne Lernout, Christel Cochez, Jean-Paul Pirnay, Walter Heuninckx
Ticks are important vectors of zoonotic pathogens affecting humans and (domestic) animals. The Ixodes ricinus tick (castor bean tick) is a chiefly European species, which can be found from Ireland to the Ural and from northern Sweden to North Africa, and has frequently been reported to bite humans [2]. Ticks primarily ‘quest’ to find hosts from spring to autumn in microenvironments with more than 85% relative humidity in woodland areas as well as in suburban and urban environments and roadsides. Ticks can become infected with various pathogens when feeding on mammals (e.g. rodents, deer, livestock) that carry these pathogens in their blood. The list of these tick-borne pathogens is expanding continuously, including Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Francisella tularensis, Rickettsia spp., Babesia divergens and Babesia microti, Neoehrlichia mikurensis, the tick-borne encephalitis virus and, last but not least, A. phagocytophilum [2,3].
Emerging and threatening vector-borne zoonoses in the world and in Europe: a brief update
Published in Pathogens and Global Health, 2019
Tularemia is caused by the gram-negative bacteria Francisella tularensis, which is one of the most virulent microorganisms currently known [93]. The lifecycle of F. tularensis takes place through terrestrial or aquatic environment. In terrestrial lifecycle, lagomorphs, rodents, and ticks are the main source of human infection and tularemia incidence is related to changes in rodent dynamics and to the expanding zone of ticks [94]. In aquatic lifecycle, the source is the water contaminated by carcasses and excrements of infected animals [94]. Tularemia outbreaks related to the aquatic lifecycle are more frequent [94]. Tularemia is highly infectious, can be easily transmitted by aerosol droplets, has a high mortality rate (up to 30%), remains in the environment for a long period of time and there is no vaccine available [93,95]. These alarming characteristics led to the consideration of tularemia as a potential bio-warfare weapon and it is currently classified as the most dangerous, category A infectious agent [81] F. tularensis was used for manufacturing of biological weapons during World War 2, although its use has never been reported [94]. Recently, tularemia has been detected in an increasing number of wild animal species, including lagomorphs, rodents, carnivores, fish and invertebrate arthropods [93]. The incidence of human tularemia is steeply increasing in Balkan countries and in Turkey [96]. In the rest of Europe, human incidence has declined, probably because of a more urban life style, decreasing number of people working outside in the countryside and a low exposition to infected wild animals [78]. However, it can represent a real threat to forest and field workers or to people living at the edge of society, such as homeless people; the transmission can be very fast and easy between them and they may comprise a center of infection outbreaks [78].