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Military Medicine Jul 2022Leptospirosis and rickettsial diseases are global zoonotic diseases. In severe infection cases, mortality can range from 10% to 30%. Currently most epidemiological data...
INTRODUCTION
Leptospirosis and rickettsial diseases are global zoonotic diseases. In severe infection cases, mortality can range from 10% to 30%. Currently most epidemiological data available are based on outbreak investigations and hospital-based studies from endemic countries. The U.S. soldiers at military bases in these countries are highly vulnerable due to the fact that most of them are immunologically naïve to these pathogens. No risk assessment of leptospirosis and rickettsial diseases among U.S. military personnel in Honduras is currently available. This study was aimed at determining the prevalence of leptospirosis and rickettsial diseases in U.S. military personnel deployed to Honduras using serological assays.
MATERIALS AND METHODS
A cohort of pre- and post-deployment sera from the most recent 1,000 military personnel stationed in Honduras for at least 6 months between 2000 and 2016 was identified for this study. Serum specimens from these eligible subjects were retrieved. All post-deployment serum specimens were screened at a dilution of 1:100 for the presence of IgG antibodies to Leptospira and Rickettsia pathogens. The pre-deployment sera from those individuals with post-deployment IgG antibodies above cutoff (i.e., seropositive) were tested to determine seroconversion. Seroconversion was defined as conversion of an optical density value from below the cutoff (i.e., negative) in a pre-deployed specimen to above the cutoff (i.e., positive) in a post-deployed specimen at a titer of 100.
RESULTS
The seropositive post-deployment specimens for antibodies against Leptospira (causing leptospirosis), Rickettsia typhi (causing murine typhus [MT]), spotted fever group rickettsioses (SFGR, causing SFG Rickettsia), Orientia tsutsugamushi (causing scrub typhus [ST]), and Coxiella burnetii (causing Q fever [QF]) were 11.6%, 11.3%, 6%, 5.6%, and 8.0%, respectively. The seroconverted rate in those assigned to Honduras from 2000 to 2016 was 7.3%, 1.9%, 3.9%, 4.3%, and 2.7% for leptospirosis, MT, SFGR, ST, and QF, respectively. Among the seroconverted specimens, 27 showed seroconversion of at least two antibodies. These seroconverted individuals accounted for 8.8% (3 out of 34) of the personnel who looked for medical attention during their deployment.
CONCLUSIONS
Our results suggest a leptospirosis seroconversion rate of 7.3%, which is higher than the 0.9% and 3.9% seroconversion in Korea and Japan, respectively. The higher rate of seroconversion indicates potential risk of Leptospira exposure. Additional testing of water samples in the pools and pits around the training sites to locate the infected areas is important to eliminate or reduce future exposure to Leptospira during trainings. The rates of seroconversion for ST, MT, spotted fever Rickettsia, and QF were 4.3%, 1.9%, 3.9%, and 2.7%, respectively, indicating the potential exposure to a variety of rickettsial-related pathogens. Testing of vectors for rickettsial pathogens in the areas could inform effective vector control countermeasures to prevent exposure. Proper precaution and protective measures are needed to better protect military personnel deployed to Honduras.
Topics: Animals; Antibodies, Bacterial; Honduras; Humans; Immunoglobulin G; Leptospira; Leptospirosis; Mice; Military Personnel; Rickettsia Infections; Scrub Typhus; Typhus, Endemic Flea-Borne
PubMed: 33861353
DOI: 10.1093/milmed/usab120 -
Journal of Vector Ecology : Journal of... Dec 2015The aim of this study was to determine the prevalence of Bartonella henselae, Rickettsia felis, and Rickettsia typhi in fleas and companion cats (serum and claws) and to...
The aim of this study was to determine the prevalence of Bartonella henselae, Rickettsia felis, and Rickettsia typhi in fleas and companion cats (serum and claws) and to assess their presence as a function of host, host habitat, and level of parasitism. Eighty-nine serum and claw samples and 90 flea pools were collected. Cat sera were assayed by IFA for Bartonella henselae and Rickettssia species IgG antibodies. Conventional PCRs were performed on DNA extracted from nails and fleas collected from cats. A large portion (55.8%) of the feline population sampled was exposed to at least one of the three tested vector-borne pathogens. Seroreactivity to B. henselae was found in 50% of the feline studied population, and to R. felis in 16.3%. R. typhi antibodies were not found in any cat. No Bartonella sp. DNA was amplified from the claws. Flea samples from 41 cats (46%) showed molecular evidence for at least one pathogen; our study demonstrated a prevalence rate of 43.3 % of Rickettsia sp and 4.4% of Bartonella sp. in the studied flea population. None of the risk factors studied (cat's features, host habitat, and level of parasitation) was associated with either the serology or the PCR results for Bartonella sp. and Rickettsia sp.. Flea-associated infectious agents are common in cats and fleas and support the recommendation that stringent flea control should be maintained on cats.
Topics: Animals; Bartonella henselae; Cat Diseases; Cat-Scratch Disease; Cats; Ecosystem; Female; Host-Pathogen Interactions; Male; Polymerase Chain Reaction; Rickettsia Infections; Rickettsia felis; Rickettsia typhi; Siphonaptera; Spain
PubMed: 26611956
DOI: 10.1111/jvec.12159 -
Scientific Reports Feb 2022Rodents living alongside humans increases the probability of encounter and also the transmission of rodent-borne diseases. Singapore's cosmopolitan urban landscape...
Rodents living alongside humans increases the probability of encounter and also the transmission of rodent-borne diseases. Singapore's cosmopolitan urban landscape provides a perfect setting to study the prevalence of four rodent-borne pathogens: Seoul hantavirus (SEOV), Leptospira species, Rickettsia typhi and Yersinia pestis, and identify the potential risk factors which may influence rodent density and transmission of rodent-borne diseases. A total of 1143 rodents were trapped from 10 unique landscape structures throughout Singapore. Real-time quantitative Polymerase Chain Reactions were used to detect pathogenic and intermediate Leptospira spp. and Yersinia pestis, whereas the seroprevalence of SEOV and R. typhi were analysed by Enzyme-Linked Immunosorbent Assay and Immunofluorescence Assay respectively. Multivariable logistic regression analysis was used to evaluate the association between prevalence of infection in rodent reservoirs and risk factors. Most of the rodents were caught in public residential developments (62.2%). Among the tested rodents, 42.4% were infected with Leptospira spp., while 35.5% and 32.2% were seropositive for SEOV and R. typhi respectively, whereas Yersinia pestis was not detected. Furthermore, risk factors including habitat, species, gender, and weight of rodents, influenced prevalence of infection to a varying extent. This study highlights the presence of Leptospira spp., SEOV and R. typhi in Singapore's rodent population, suggesting the need for effective rodent management and sanitation strategies to prevent further circulation and transmission to humans.
Topics: Animals; Disease Reservoirs; Humans; Leptospira; Rickettsia typhi; Rodentia; Seoul virus; Seroepidemiologic Studies; Singapore; Zoonoses
PubMed: 35177639
DOI: 10.1038/s41598-021-03954-w -
Tropical Medicine and Infectious Disease Sep 2020are the causative agents of murine typhus and cat-scratch disease, respectively. A small-scale survey (N = 202) was conducted in the Attica region, Greece, for...
are the causative agents of murine typhus and cat-scratch disease, respectively. A small-scale survey (N = 202) was conducted in the Attica region, Greece, for determining the prevalence rates of IgG antibodies against and by indirect fluorescence antibody test. IgG against and were present in 17.8% (36/202) and 4.5% (9/202) of the participants, respectively; co-occurring IgG against both and were detected in 3.5% (7/202), whereas only anti- IgG in 14.3% (29/202), and only anti- IgG in 1.0% (2/202). Titres 1/64, 1/128, 1/256, and 1/512, of anti- IgG were identified in 6.4%, 4.5%, 4.5%, and 2.4%, whereas titres 1/40 and 1/80 of anti- IgG were detected in 4.0%, and 0.5%, respectively. A positive association of anti- IgG prevalence with a coastal area featuring a major seaport ( = 0.009) and with younger age ( = 0.046) was identified. The findings of this survey raise concern for exposure of the population of Attica to and , which should be considered in the differential diagnosis when compatible symptoms are present. Our results also suggest that seaports may represent high-risk areas for exposure to spp.
PubMed: 32947795
DOI: 10.3390/tropicalmed5030145 -
Journal of Infection in Developing... Oct 2020Rickettsioses are zoonotic diseases caused by pathogenic bacteria of the genus Rickettsia and transmitted to man by means of arthropod vectors such as ticks, fleas,...
INTRODUCTION
Rickettsioses are zoonotic diseases caused by pathogenic bacteria of the genus Rickettsia and transmitted to man by means of arthropod vectors such as ticks, fleas, mites and lice. Historically, Caldas Department has reported a significant number of cases of murine typhus to the Colombian national health surveillance system, and consequent studies of flea-borne rickettsiosis identified the circulation of Rickettsia typhi and Rickettsia felis in multiple municipalities. Our aim was to genotype species of Rickettsia detected in fleas collected from domestic and wild mammals in Caldas.
METHODOLOGY
Flea samples were taken by convenience sampling from dogs, cats and wild mammals (rodents and marsupials) in 26 municipalities. Specimens were classified by current taxonomic keys and pooled for DNA extraction and molecular screening for Rickettsia spp. by PCR amplification of gltA, htrA and sca5 genes. Positive samples were genotyped by enzyme digestion (htrA) and sequencing.
RESULTS
A total of 1388 flea samples were collected. Rickettsia DNA was amplified in 818 (gltA), 883 (htrA) and 424 (sca5) flea pools. Alignment analysis with available Rickettsia DNA sequences showed greater similarity with R. asembonensis (gltA) and with R. felis (sca5 and htrA). Restriction pattern was compatible with R. felis. R. typhi was not identified.
CONCLUSION
The present study confirms the presence and high prevalence of R. asembonensis and R. felis in fleas from domestic and wild animals in different municipalities from Caldas Department.
Topics: Animals; Animals, Domestic; Animals, Wild; Cats; Colombia; Dogs; Flea Infestations; Genotype; Mammals; Rickettsia; Rickettsia Infections; Rodentia; Siphonaptera; Zoonoses
PubMed: 33175711
DOI: 10.3855/jidc.12524 -
Vector Borne and Zoonotic Diseases... Jul 2016In high-income countries, homeless individuals in urban areas often live in crowded conditions with limited sanitation and personal hygiene. The environment of... (Review)
Review
INTRODUCTION
In high-income countries, homeless individuals in urban areas often live in crowded conditions with limited sanitation and personal hygiene. The environment of homelessness in high-income countries may result in intensified exposure to ectoparasites and urban wildlife, which can transmit infections. To date, there have been no systematic evaluations of the published literature to assess vector-borne and zoonotic disease risk to these populations.
OBJECTIVES
The primary objectives of this study were to identify diversity, prevalence, and risk factors for vector-borne and zoonotic infections among people experiencing homelessness and extreme poverty in urban areas of high-income countries.
METHODS
We conducted a systematic review and narrative synthesis of published epidemiologic studies of zoonotic and vector-borne infections among urban homeless and very poor people in the United States and Europe from 1990 to 2014.
RESULTS
Thirty-one observational studies and 14 case studies were identified (n = 45). Seroprevalence to the human louse-borne pathogen Bartonella quintana (seroprevalence range: 0-37.5%) was identified most frequently, with clinical disease specifically observed among HIV-positive individuals. Seropositivity to Bartonella henselae (range: 0-10.3%) and Rickettsia akari (range: 0-16.2%) was noted in multiple studies. Serological evidence of exposure to Rickettsia typhi, Rickettsia prowazekii, Bartonella elizabethae, West Nile virus, Borellia recurrentis, lymphocytic choriomeningitis virus, Wohlfartiimonas chitiniclastica, Seoul hantavirus (SEOV), and Leptospira species was also identified in published studies, with SEOV associated with chronic renal disease later in life. HIV infection, injection drug use, and heavy drinking were noted across multiple studies as risk factors for infection with vector-borne and zoonotic pathogens.
CONCLUSIONS
B. quintana was the most frequently reported vector-borne infection identified in our article. Delousing efforts and active surveillance among HIV-positive individuals, who are at elevated risk of complication from B. quintana infection, are advised to reduce morbidity. Given documented exposure to rodent-borne zoonoses among urban homeless and marginalized people, reducing human contact with rodents remains an important public health priority.
Topics: Animals; Bacterial Infections; Europe; Ill-Housed Persons; Humans; Social Marginalization; United States; Zoonoses
PubMed: 27159039
DOI: 10.1089/vbz.2015.1863 -
Journal of Medical Entomology Jul 2017Flea-borne rickettsiosis occurs worldwide and includes a number of pathogens, namely, Rickettsia typhi and Rickettsia felis. Most studies in the United States have...
Flea-borne rickettsiosis occurs worldwide and includes a number of pathogens, namely, Rickettsia typhi and Rickettsia felis. Most studies in the United States have occurred in southern Texas and California where flea-borne rickettsiosis is endemic, resulting in a lack of information from other regions of the country. Between March and August 2016, 222 fleas were collected from 52 client-owned dogs and cats in two urban areas in Oklahoma. Fleas were identified using morphological characteristics then pooled and tested by polymerase chain reaction (PCR) using published primers for gltA, ompB, and 17-kDa. The majority (98.6%) of fleas collected were Ctenocephalides felis (Bouché) followed by Pulex irritans (L) (1.4%). Overall, fleas collected from 30.0% (6/20) cats and 43.8% (14/32) dogs were infected with R. felis. Three C. felis-pools collected from three dogs, two in the Enid area (central Oklahoma) and one in the Elk City area (western Oklahoma), were infected with R. typhi as well as R. felis. 'Candidatus R. senegalensis' was detected in one pool of fleas taken from a cat in Oklahoma City. This is the first evidence that flea-borne Rickettsia species occur in fleas obtained from client-owned dogs and cats in the Great Plains region. The impact of these Rickettsia species on public health in the region needs further investigation.
Topics: Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Flea Infestations; Oklahoma; Polymerase Chain Reaction; Prevalence; Rickettsia Infections; Rickettsia felis; Rickettsia typhi; Siphonaptera; Typhus, Endemic Flea-Borne
PubMed: 28399210
DOI: 10.1093/jme/tjx069 -
IDCases 2020A 39 year-old male was residing along the south coast of Texas, the USA, presented with fever, myalgias, headaches, and weight loss for ten days. Symptoms and...
A 39 year-old male was residing along the south coast of Texas, the USA, presented with fever, myalgias, headaches, and weight loss for ten days. Symptoms and manifestations progressed to include nuchal rigidity, photophobia, hyponatremia, thrombocytopenia, and transaminitis despite the intravenous administration of ceftriaxone and azithromycin. A lumbar puncture performed in the Emergency Department yielded pleocytosis and glucose cerebrospinal fluid/serum ratio of 0.35, suggestive of meningoencephalitis. Conglomerate data raised the suspicion of meningitis secondary to a zoonotic acquired infection, which was later confirmed to be . Doxycycline is the drug of choice for the suspected disease. After doxycycline administration, the patient improved and was discharged home asymptomatic.
PubMed: 32509531
DOI: 10.1016/j.idcr.2020.e00852 -
Journal of Infection in Developing... Sep 2017Rickettsia sibirica mongolitimonae was recently reported as a common rickettsiosis in France. Current serological evidence suggests the presence of scrub typhus and...
INTRODUCTION
Rickettsia sibirica mongolitimonae was recently reported as a common rickettsiosis in France. Current serological evidence suggests the presence of scrub typhus and spotted fever group rickettsiosis in Sri Lanka. We detected a human case of R. sibirica mongolitimonae in Sri Lanka.
METHODOLOGY
A skin biopsy of the eschar was tested for the presence of Rickettsia spp. using qPCR assay targeting a 109-bp fragment of a hypothetical protein and by PCR amplification and sequencing targeting the ompA gene.
RESULTS
A 30-year-old woman who had just returned from travel to a jungle in Sri Lanka was evaluated as an outpatient for fever. Examination revealed an enlarged axillary lymph node, a maculopapular rash and an eschar at her left flank and a skin biopsy of the eschar was performed. The skin biopsy was positive for the presence of Rickettsia spp. by qPCR and PCR amplification and sequencing targeting the ompA gene revealed R. sibirica mongolitimonae. Immunofluorescence assay on an acute serum sample for spotted fever group rickettsial antigens (Rickettsia conorii conorii, R. sibirica mongolitimonae, Rickettsia felis) and typhus group rickettsiae (Rickettsia typhi) was negative. The patient was treated by oral doxycycline (200 mg/day) for one week.
CONCLUSIONS
R. sibirica mongolitimonae should be considered in the differential diagnosis of patients with suspected rickettsiosis in, or returning from, Sri Lanka.
PubMed: 31085830
DOI: 10.3855/jidc.8743 -
Acta Tropica Feb 2017Murine or endemic typhus, a febrile disease caused by Rickettsia typhi, is often misdiagnosed due to its non-specific presentation. We sought to evaluate all available... (Review)
Review
Murine or endemic typhus, a febrile disease caused by Rickettsia typhi, is often misdiagnosed due to its non-specific presentation. We sought to evaluate all available evidence in the literature regarding the clinical and laboratory manifestations, epidemiological characteristics, and outcomes of murine typhus. Pubmed was searched for all articles providing available data. In an effort to incorporate contemporary data, only studies from 1980 were included. Thirty-three case series including 2074 patients were included in final analysis. Available evidence suggests that the classic triad of fever, headache and rash is encountered in only one-third of patients. Other frequent symptoms were chills, malaise, myalgia, and anorexia. A tetrad of reported laboratory abnormalities consisting of elevated liver enzymes, lactate dehydrogenase, erythrocyte sedimentation rate and hypoalbuminemia was detected. Complications were observed in one-fourth of patients, reported mortality was extremely low, but untreated patients had notably longer duration of fever. Among epidemiological characteristics, a seasonal distribution with most cases reported during warmer months, was the most prominent finding. Murine typhus in children exhibits several different characteristics, with abdominal pain, diarrhea, and sore throat reported more commonly, higher frequency of anemia, lower frequency of hypoalbuminemia, hematuria and proteinuria and a much lower rate of complications. This systematic review of published evidence provides a thorough description of the clinical and laboratory features of murine typhus and highlights important differences in children.
Topics: Animals; Child; Exanthema; Fever; Headache; Humans; Treatment Outcome; Typhus, Endemic Flea-Borne
PubMed: 27983969
DOI: 10.1016/j.actatropica.2016.10.018