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Emerging Infectious Diseases Nov 2023Murine typhus is a febrile, fleaborne disease caused by infection with Rickettsia typhi bacteria. Cases can range from mild and nonspecific to fatal. We report 2 cases...
Murine typhus is a febrile, fleaborne disease caused by infection with Rickettsia typhi bacteria. Cases can range from mild and nonspecific to fatal. We report 2 cases of murine typhus in Costa Rica, confirming the presence and circulation of R. typhi causing severe disease in the country.
Topics: Animals; Mice; Humans; Typhus, Endemic Flea-Borne; Costa Rica; Rickettsia typhi; Rickettsia
PubMed: 37877575
DOI: 10.3201/eid2911.221561 -
Vector Borne and Zoonotic Diseases... Apr 2024Flea-borne rickettsioses, collectively referred to as a term for etiological agents , , and RFLOs (-like organisms), has become a public health concern around the...
Flea-borne rickettsioses, collectively referred to as a term for etiological agents , , and RFLOs (-like organisms), has become a public health concern around the world, specifically in the United States. Due to a shared arthropod vector (the cat flea) and clinical signs, discriminating between species has proven difficult. While the effects of microbial coinfections in the vector can result in antagonistic or synergistic interrelationships, subsequently altering potential human exposure and disease, the impact of bacterial interactions within flea populations remains poorly defined. In this study, and systems were utilized to assess rickettsial interactions in arthropods. Coinfection of both and within a tick-derived cell line indicated that the two species could infect the same cell, but distinct growth kinetics led to reduced growth over time, regardless of infection order. Sequential flea coinfections revealed the vector could acquire both spp. and sustain coinfection for up to 2 weeks, but rickettsial loads in coinfected fleas and feces were altered during coinfection. Altered rickettsial loads during coinfection suggest and interactions may enhance the transmission potential of either agent. Thus, this study provides a functional foundation to disentangle transmission events propelled by complex interspecies relationships during vector coinfections.
Topics: Animals; Humans; Cats; Rickettsia typhi; Rickettsia felis; Ctenocephalides; Coinfection; Rickettsia; Siphonaptera; Flea Infestations; Felis; Cat Diseases
PubMed: 38422214
DOI: 10.1089/vbz.2023.0122 -
Veterinary World Aug 2023Scrub typhus and murine typhus are globally distributed zoonoses caused by the intracellular Gram-negative bacteria and , respectively. Numerous studies have been...
BACKGROUND AND AIM
Scrub typhus and murine typhus are globally distributed zoonoses caused by the intracellular Gram-negative bacteria and , respectively. Numerous studies have been undertaken on rickettsial illnesses in humans and animals, including arthropod vectors, in Thailand. However, the reports on the seroprevalence of antibodies to and in buffaloes is extremely rare. Thus, this study aimed to estimate the seroprevalence of both rickettsial infections in water buffaloes () in Phatthalung Province, southern Thailand.
MATERIALS AND METHODS
From February to March 2023, a total of 156 serum samples were collected from 156 water buffaloes on 29 farms in Phatthalung province. The sera were screened for antibodies against and using an indirect immunofluorescence assay.
RESULTS
The seroprevalence of antibodies against and in individual water buffaloes was 4.49% (95% confidence interval [CI]: 2.19%-8.97%) and 3.85% (95% CI: 1.77%-8.14%), respectively, whereas 31% (9/29) of the herds had buffaloes with antibodies. The number of buffaloes with scrub typhus infection and ectoparasite infestation was statistically significant (p < 0.05; odds ratio = 6.25 [95% CI: 1.19-33.33]). Intriguingly, the prevalence of scrub typhus antibodies in buffaloes that were not infested with ectoparasites was much higher than those that were.
CONCLUSION
This is the first report of and antibodies in water buffalo sera in Southern Thailand. Two serum samples showed a high antibody titer against . Seroprevalence mainly occurred in non-ectoparasite-infested buffaloes, especially for antibodies. At the herd level, one-third of the studied farms showed seroprevalence. Additional research on the occurrence of these pathogens in vectors and in other animal reservoirs is necessary.
PubMed: 37766717
DOI: 10.14202/vetworld.2023.1600-1604 -
The American Journal of Tropical... Jan 2024
Topics: Animals; Humans; Siphonaptera; Rickettsia typhi; Typhus, Endemic Flea-Borne; Rickettsia Infections; California; Rickettsia; Rickettsia felis
PubMed: 38109770
DOI: 10.4269/ajtmh.23-0742 -
Life (Basel, Switzerland) Sep 2023Different vector-borne pathogens are present or have (re-)emerged in Croatia. Flaviviruses tick-borne encephalitis (TBEV), West Nile (WNV), and Usutu (USUV) are widely... (Review)
Review
Different vector-borne pathogens are present or have (re-)emerged in Croatia. Flaviviruses tick-borne encephalitis (TBEV), West Nile (WNV), and Usutu (USUV) are widely distributed in continental regions, while Toscana virus (TOSV) and sandfly fever viruses are detected at the Croatian littoral. Recently, sporadic clinical cases of Tahyna orthobunyavirus (TAHV) and Bhanja bandavirus infection and seropositive individuals have been reported in continental Croatia. Acute infections and serologic evidence of WNV, TBEV, USUV, and TAHV were also confirmed in sentinel animals and vectors. Autochthonous dengue was reported in 2010 at the Croatian littoral. Lyme borreliosis is the most widely distributed vector-borne bacterial infection. The incidence is very high in northwestern and eastern regions, which correlates with numerous records of ticks. Acute human infections are reported sporadically, but there are many records of serologic evidence of anaplasmosis in animals. Mediterranean spotted fever () and murine typhus () are the main rickettsial infections in Croatia. Human leishmaniasis is notified sporadically, while serologic evidence of leishmaniasis was found in 11.4% of the Croatian population. After the official eradication of malaria in 1964, only imported cases were reported in Croatia. Since vector-borne diseases show a growing trend, continuous monitoring of vectors is required to protect the population from these infections.
PubMed: 37763260
DOI: 10.3390/life13091856 -
Emerging Infectious Diseases Jul 2023To elucidate the epidemiology of murine typhus, which is infrequently reported in Japan, we conducted a cross-sectional study involving 2,382 residents of...
To elucidate the epidemiology of murine typhus, which is infrequently reported in Japan, we conducted a cross-sectional study involving 2,382 residents of rickettsiosis-endemic areas in Honshu Island during August-November 2020. Rickettsia typhi seroprevalence rate was higher than that of Orientia tsutsugamushi, indicating that murine typhus is a neglected disease.
Topics: Animals; Mice; Humans; Typhus, Endemic Flea-Borne; Scrub Typhus; Seroepidemiologic Studies; Japan; Cross-Sectional Studies; Orientia tsutsugamushi; Rickettsia typhi
PubMed: 37347821
DOI: 10.3201/eid2907.230037 -
Infectious Disease Reports Oct 2023Murine typhus is an acute febrile illness caused by , an obligately intracellular Gram-negative coccobacillus. Rats () and their fleas () serve as the reservoir and... (Review)
Review
Murine typhus is an acute febrile illness caused by , an obligately intracellular Gram-negative coccobacillus. Rats () and their fleas () serve as the reservoir and vector of , respectively. Humans become infected when -infected flea feces are rubbed into flea bite wounds or onto mucous membranes. The disease is endemic throughout much of the world, especially in tropical and subtropical seaboard regions where rats are common. Murine typhus is reemerging as an important cause of febrile illness in Texas and Southern California, where an alternate transmission cycle likely involves opossums () and cat fleas (). Although primarily an undifferentiated febrile illness, a range of neurologic manifestations may occur, especially when treatment is delayed. Serology is the mainstay of diagnostic testing, but confirmation usually requires demonstrating seroconversion or a fourfold increase in antibody titer from acute- and convalescent-phase sera (antibodies are seldom detectable in the first week of illness). Thus, early empiric treatment with doxycycline, the drug of choice, is imperative. The purpose of this review is to highlight murine typhus as an important emerging and reemerging infectious disease, review its neurologic manifestations, and discuss areas in need of further study.
PubMed: 37987401
DOI: 10.3390/idr15060063 -
Travel Medicine and Infectious Disease 2024Rickettsia is a zoonotic bacterial pathogen transmitted by vectors and has extensive reservoirs in animal and human populations. Rickettsiosis is a public health problem... (Review)
Review
SUBJECT
Rickettsia is a zoonotic bacterial pathogen transmitted by vectors and has extensive reservoirs in animal and human populations. Rickettsiosis is a public health problem all over the world. However, comprehensive information on the geographical distribution of different Rickettsia species, infection status of reservoirs, vectors, and human cases is lacking in most parts of the world. Therefore, this study aimed to investigate the geographical distribution of different Rickettsia species and their vectors in countries of the WHO-EMRO region.
METHODS
In this review study, a search was conducted for reports and published studies on Rickettsia species from WHO-EMRO region countries in various databases from 1995 to 2022. Finally, the reported status of human cases, reservoirs, and vectors associated with each species in different countries was documented.
RESULTS
Reports of infections related to the detection of Rickettsia species were only available for 15 out of 22 WHO-EMRO member countries. A total of twenty-four Rickettsia species, including R. sibrica, R. lusitaniae, R. africae, R. prowazekii, R. felis, R. typhi, R. rickettsii, R. aeschlimannii, R. conorii, R. massiliae, R. helvetica, R. monacensis, R. rhipicephali, R. bellii, R. asembonensis, R. hoogstraalii, R. andeanae, R. raoultii, R. asiatica, R. slovaca, R. australis, R. barbariae, Candidatus R. amblyommii, and Candidatus R. goldwasserii, were reported from WHO-EMRO member countries. Furthermore, human cases infected with six different Rickettsia species, including R. sibrica, R. prowazekii, R. felis, R. typhi, R. rickettsii, R. aeschlimannii, R. conorii, R. massiliae, and R. helvetica, were reported from these countries.
CONCLUSION
The vast diversity of Rickettsia vectors has contributed to the ongoing discovery of new Rickettsia species. Therefore, further research on the reservoir hosts of Rickettsia infections in the understudied WHO-EMRO region is crucial. This research sheds light on Rickettsia disease's epidemiology and transmission dynamics in this region.
Topics: Animals; Humans; Rickettsia; Rickettsia Infections; World Health Organization
PubMed: 38360158
DOI: 10.1016/j.tmaid.2024.102695 -
Infection Dec 2023The number of homeless people in Germany is steadily increasing. Due to their often precarious living conditions, this specific population may be increasingly exposed to...
PURPOSE
The number of homeless people in Germany is steadily increasing. Due to their often precarious living conditions, this specific population may be increasingly exposed to ectoparasites that can transmit various pathogens. To assess the prevalence and thus the risk of such infections, we analyzed the seropositivity of rickettsiosis, Q fever, tularemia and bartonellosis in homeless individuals.
METHODS
A total of 147 homeless adults from nine shelters in Hamburg, Germany, were included. The individuals underwent questionnaire-based interviewing, physical examination, and venous blood was drawn between May and June 2020. Blood samples were analyzed for antibodies against rickettsiae (Rickettsia typhi and R. conorii), Coxiella burnetii, Francisella tularensis and bartonellae.
RESULTS AND CONCLUSION
A very low seroprevalence of R. typhi and F. tularensis infection was found (0-1%), while antibodies against R. conorii and C. burnetii were more common (7% each), followed by a relatively high seroprevalence of 14% for bartonellosis. Q fever seroprevalence was associated with the country of origin, whereas bartonellosis seroprevalence was associated with the duration of homelessness. Preventive measures targeting ectoparasites, especially body lice, should be put in place continuously.
Topics: Adult; Animals; Humans; Q Fever; Arthropods; Seroepidemiologic Studies; Bacterial Infections; Coxiella burnetii; Bartonella Infections; Ill-Housed Persons; Antibodies, Bacterial
PubMed: 37289422
DOI: 10.1007/s15010-023-02059-y -
MMWR. Morbidity and Mortality Weekly... Aug 2023Fleaborne typhus (also known as murine typhus), a widely distributed vectorborne zoonosis caused by Rickettsia typhi, is a moderately severe, but infrequently fatal...
Fleaborne typhus (also known as murine typhus), a widely distributed vectorborne zoonosis caused by Rickettsia typhi, is a moderately severe, but infrequently fatal illness; among patients who receive doxycycline, the case-fatality rate is <1%. Fleaborne typhus is a mandated reportable condition in California. Reported fleaborne typhus cases in Los Angeles County have been increasing since 2010, with the highest number (171) reported during 2022. During June-October 2022, Los Angeles County Department of Public Health learned of three fleaborne typhus-associated deaths. This report describes the clinical presentation, illness course, and methods used to diagnose fleaborne typhus in these three cases. Severe fleaborne typhus manifestations among these cases included hemophagocytic lymphohistiocytosis, a rare immune hyperactivation syndrome that can occur in the infection setting; myocarditis; and septic shock with disseminated intravascular coagulation. Increased health care provider and public health awareness of the prevalence and severity of fleaborne typhus and of the importance of early doxycycline therapy is essential for prevention and treatment efforts.
Topics: Mice; Humans; Doxycycline; Typhus, Epidemic Louse-Borne; Los Angeles; Typhus, Endemic Flea-Borne; Rickettsia typhi; Animals
PubMed: 37535465
DOI: 10.15585/mmwr.mm7231a1