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1.
Microbiome ; 11(1): 50, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36915209

RESUMO

BACKGROUND: The impact of host skin microbiome on horizontal transmission of tick-borne pathogens , and of pathogen associated transstadial and transovarial changes in tick microbiome are largely unknown, but are important to control increasingly emerging tick-borne diseases worldwide. METHODS: Focusing on a rickettsiosis pathogen, Rickettsia raoultii, we used R. raoultii-positive and R. raoultii-negative Dermacentor spp. tick colonies to study the involvement of skin microbiota in cutaneous infection with rickettsiae in laboratory mice, and the function of the tick microbiome on maintenance of rickettsiae through all tick developmental stages (eggs, larvae, nymphs, adults) over two generations. RESULTS: We observed changes in the skin bacteria community, such as Chlamydia, not only associated with rickettsial colonization but also with tick feeding on skin. The diversity of skin microbiome differed between paired tick-bitten and un-bitten sites. For vertical transmission, significant differences in the tick microbiota between pathogenic rickettsia-positive and -negative tick chorts was observed across all developmental stages at least over two generations, which appeared to be a common pattern not only for R. raoultii but also for another pathogenic species, Candidatus Rickettsia tarasevichiae. More importantly, bacterial differences were complemented by functional shifts primed for genetic information processing during blood feeding. Specifically, the differences in tick microbiome gene repertoire between pathogenic Rickettsia-positive and -negative progenies were enriched in pathways associated with metabolism and hormone signals during vertical transmission. CONCLUSIONS: We demonstrate that host skin microbiome might be a new factor determining the transmission of rickettsial pathogens through ticks. While pathogenic rickettsiae infect vertebrate hosts during blood-feeding by the tick, they may also manipulate the maturation of the tick through changing the functional potential of its microbiota over the tick's life stages. The findings here might spur the development of new-generation control methods for ticks and tick-borne pathogens. Video Abstract.


Assuntos
Ixodidae , Infecções por Rickettsia , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Camundongos , Ixodidae/microbiologia , Infecções por Rickettsia/microbiologia , Doenças Transmitidas por Carrapatos/microbiologia , Larva/microbiologia
2.
Emerg Infect Dis ; 28(10): 2132-2134, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36148970

RESUMO

We conducted enhanced acute febrile illness surveillance in an urban slum community in Salvador, Brazil. We found that rickettsial infection accounted for 3.5% of urgent care visits for acute fever. Our results suggest that rickettsiae might be an underrecognized, treatable cause of acute febrile illness in impoverished urban populations in Brazil.


Assuntos
Infecções por Rickettsia , Rickettsia , Anticorpos Antibacterianos , Brasil/epidemiologia , Febre/epidemiologia , Humanos , Áreas de Pobreza , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/epidemiologia
3.
Parasit Vectors ; 15(1): 162, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35526060

RESUMO

BACKGROUND: The raccoon Procyon lotor (Linnaeus, 1758) (Carnivora; Procyonidae) is one of the most important and most intensively studied invasive mammal species in Europe. Within the last 30 years the raccoon has spread at an increasing rate, resulting in the establishment of local populations in various regions of Europe. In these newly colonised areas, gaps in knowledge of the raccoon's biology concern not only most aspects of its ecology in a broad sense, but also its pathogens and parasites. Most micropathogens recorded hitherto in the raccoons that have colonised Europe have documented epizootic and zoonotic potential. Thus, it is considered especially important to investigate the role played by the raccoon in the spread of pathogens through both animal-animal and animal-human pathways. METHODS: Tissue samples of raccoons from Poland and Germany were examined in this study. In total, 384 tissue samples from 220 raccoons (170 spleen samples, 82 liver biopsies, 132 ear biopsies) were examined using molecular methods. The presence of Rickettsia spp. DNA was screened through amplification of a fragment of the gltA gene. Samples that were PCR positive for gltA were tested for other rickettsial genes, ompB and a 17-kDa antigen. For taxonomic purposes, the obtained sequences were compared with corresponding sequences deposited in GenBank using the Basic Local Alignment Search Tool, and phylogenetic analyses were conducted using Bayesian inference implemented in MrBayes software. RESULTS: Rickettsia DNA was confirmed only in skin biopsies; no isolates from the spleen or liver were positive for Rickettsia DNA. With the exception of one sample from Germany, which was positive for Rickettsia helvetica DNA, all the samples positive for Rickettsia DNA derived from the Polish population of raccoons. DNA of Rickettsia spp. was detected in 25 samples, i.e. 11.4% of the tested raccoons, and R. helvetica was confirmed in 52% of the positive samples. Additionally, single cases of Rickettsia monacensis, Rickettsia raoultii, and Candidatus Rickettsia kotlanii-like were found, and in 32% of all the positive samples similarity was shown to different Rickettsia endosymbionts. Out of the samples that tested positive for gltA, amplicons of ompB and 17 kDa were successfully sequenced from 14 and three samples, respectively. CONCLUSIONS: To the best of our knowledge, this study provides, for the first time, evidence of the occurrence of Rickettsia pathogens and endosymbionts in the European population of raccoons. Further, broader research on different species of wild vertebrates, and ticks, as potential vectors and hosts for tick-borne pathogens, in natural as well as in peri-urban environments, is therefore required.


Assuntos
Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Animais , Teorema de Bayes , Filogenia , Guaxinins
4.
Chinese Journal of Endemiology ; (12): 966-971, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991555

RESUMO

Objective:To investigate the infection of spotted fever group Rickettsiae (SFGR) and Rickettsia mooseri ( R.mooseri) of wild rodents in the field of plague foci in Western Yunnan. Methods:The DNA of liver samples of 2 512 wild rodents captured from the plague foci in Lianghe County, Jianchuan County and Yulong County in Western Yunnan from 2015 to 2016 was extracted by magnetic bead method, and the heat shock protein groEL gene primers were used for nested PCR amplification. Gene sequence splicing and Blast homology comparison were performed using DNAStar 7.1 software and GenBank of the National Center for Biotechnology Information (NCBI) of the United States, respectively, and DNAStar 7.1 and MEGA 6.0 softwares were used to construct phylogenetic trees.Results:The wild rodents infected with SFGR were Mus pahari, Rattus steini, Crocidura attenuata and Suncus murinus (one for each), with a total infection rate of 0.16% (4/2 512); no R.mooseri infection was detected. The SFGR infection rates of wild rodents in the plague foci of Lianghe County and Jianchuan County were 0.49% (3/611) and 0.10% (1/1 029), respectively; no SFGR infection was detected in the wild rodents in the plague foci of Yulong County. The homology analysis showed that the homology between SFGR positive samples and reference sequences was 95.45%-100.00%; some of the groEL gene sequences were highly similar among the four positive samples, and the homology was 89.60%-97.40%. Sequence evolution analysis showed that the sequences of three SFGR positive samples from the plague focus in Lianghe County were clustered in the same branch, and the homology reached 94.40%-97.40%; one positive sample sequence from the plague focus in Jianchuan County was clustered in one branch. Conclusion:SFGR infection rate of wild rodents in the field of plague foci in Western Yunnan is low, and no R.mooseri infection is found.

5.
Pathogens ; 10(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34832589

RESUMO

Tick-borne spotted fever group (SFG) rickettsioses were neglected in Taiwan. The study reported a seroepidemiological survey of SFG rickettsiae in residents in Gongliao District, Northeast Taiwan. Blood samples were examined for antibodies against SFG rickettsiae by enzyme-linked immunosorbent assay and immunofluorescence assay. Risk factors were assessed using logistic regression. Ticks parasitizing dogs were collected within a 2 km radius from the houses of seropositive participants, and PCR was performed to detect possible tick-borne pathogens. Of 1108 participants, 75 (6.8%) had antibodies against SFG rickettsiae. Residents were more likely to be seropositive if they were older than 65 years, recruited by Dr. Enjoy's Clinic, or resided in Jilin village. A total of 184 ticks including 5 species (Rhipicephalus sanguineus, Rhipicephalus haemaphysaloides, Dermacentor auratus, Haemaphysalis hystricis, Haemaphysalis ornithophila) were collected. Rickettsia spp. were detected in 6.5% (12/184) of ticks. Rickettsia sp. TwKM01 was found in 6 R. sanguineus and 4 R. haemaphysaloides; while Rickettsia sp. TwKM03 was identified in 1 R. sanguineus. Moreover, gene-based pairwise analysis indicated identification of a putative new species, Rickettsia sp. Da-1, in D. auratus. These findings provided evidence of SFG rickettsiae infection in ticks and suggested SFG rickettsiae exposure in the residents.

7.
J Med Entomol ; 58(6): 2398-2405, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34007993

RESUMO

During September-December 2018, 25 live ticks were collected on-post at Fort Leavenworth, Kansas, in a home with a history of bat occupancy. Nine ticks were sent to the Army Public Health Center Tick-Borne Disease Laboratory and were identified as Carios kelleyi (Cooley and Kohls, 1941), a species that seldom bites humans but that may search for other sources of blood meals, including humans, when bats are removed from human dwellings. The ticks were tested for numerous agents of human disease. Rickettsia lusitaniae was identified by multilocus sequence typing to be present in two ticks, marking the first detection of this Rickettsia agent in the United States and in this species of tick. Two other Rickettsia spp. were also detected, including an endosymbiont previously associated with C. kelleyi and a possible novel Rickettsia species. The potential roles of C. kelleyi and bats in peridomestic Rickettsia transmission cycles warrant further investigation.


Assuntos
Argasidae/microbiologia , Rickettsia/isolamento & purificação , Infestações por Carrapato/parasitologia , Animais , Argasidae/crescimento & desenvolvimento , Feminino , Habitação , Kansas , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia
8.
J Med Entomol ; 58(3): 1363-1369, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33399212

RESUMO

Spotted fever group rickettsiae, mainly maintained and transmitted by ticks, are important etiological agents of (re)emerging zoonotic diseases worldwide. It is of great significance to investigate spotted fever group rickettsiae in ticks in different areas for the prevention and control of rickettsioses. In this study, a total of 305 ticks were collected from wild and domestic animals in Chongqing, Guizhou, Yunnan, and Guangxi provinces of southwestern China during 2017-2019 and examined for the presence of spotted fever group rickettsiae by PCR with primers targeting the partial gltA, ompA, rrs, and htrA genes. Results showed that two spotted fever group rickettsiae species, including the pathogenic Candidatus Rickettsia jingxinensis (Rickettsiales: Rickettsiaceae) and a potential novel species Rickettsia sp. sw (Rickettsiales: Rickettsiaceae), were identified. The Ca. R. jingxinensis sequences were recovered from Rhipicephalus microplus (Ixodida: Ixodidae) and Haemaphysalis longicornis (Ixodida: Ixodidae) ticks and phylogenetically clustered with previous Ca. R. jingxinensis, Ca. R. longicornii (Rickettsiales: Rickettsiaceae), and Rickettsia sp. XY118 (Rickettsiales: Rickettsiaceae) strains. Rickettsia sp. sw was detected in Amblyomma geoemydae (Ixodida: Ixodidae) and Rh. microplus. Interestingly, as far as we know, this was the first report of Rickettsia (Rickettsiales: Rickettsiaceae) in A. geoemydae. Phylogenetic analyses indicated that this potential novel species was closely related to R. aeschlimannii (Rickettsiales: Rickettsiaceae) with gltA and ompA genes and grouped in a cluster composed of R. montanensis (Rickettsiales: Rickettsiaceae), R. raoultii (Rickettsiales: Rickettsiaceae), R. aeschlimannii, R. massiliae (Rickettsiales: Rickettsiaceae), and R. rhipicephali (Rickettsiales: Rickettsiaceae) with htrA, while formed a separate clade with rrs. The pathogenicity of Rickettsia sp. sw should be further confirmed. These results expand the knowledge of the geographical distribution and vector distribution of spotted fever group rickettsiae in China and are useful for assessing the potential public health risk.


Assuntos
Ixodidae/microbiologia , Rickettsia/isolamento & purificação , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , China , Feminino , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Rhipicephalus/microbiologia , Rickettsiose do Grupo da Febre Maculosa/transmissão
9.
J Trop Pediatr ; 67(3)2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32607585

RESUMO

Seasonal outbreaks of acute encephalitis syndrome have been occurring in Gorakhpur division in the Indian state of Uttar Pradesh during monsoon and post-monsoon months. Orientia tsutsugamushi was identified as the major aetiology of these outbreaks. Orientia tsutsugamushi was also identified as one of the important aetiology of febrile illness among children attending peripheral health facilities. The present study was undertaken to detect antibodies against spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) among children with acute febrile illness presenting at peripheral health facilities in Gorakhpur district. Of the 224 blood samples tested, SFGR infection was detected in 13 (6%) patients. None of the samples tested positive for TGR.


Assuntos
Encefalopatia Aguda Febril , Orientia tsutsugamushi , Rickettsia , Tifo por Ácaros , Rickettsiose do Grupo da Febre Maculosa , Anticorpos Antibacterianos , Criança , Humanos , Índia/epidemiologia , Tifo por Ácaros/complicações , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/diagnóstico , Rickettsiose do Grupo da Febre Maculosa/epidemiologia
10.
Ann Agric Environ Med ; 27(4): 505-511, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33356053

RESUMO

Rickettsiae from the spotted fever group, i.e. the etiological agents of tick-borne lymphadenopathy/Dermacentor-borne necrotic erythema and lymphadenopathy (TIBOLA /DEBONEL) syndrome, are associated with ticks, including Dermacentor marginatus and Dermacentor reticulatus. The expansion of these ticks into new areas increases the risk of infection of their hosts with tick-borne pathogens. The study summarises the importance of 2 species from the genus Dermacentor, i.e. D. marginatus and D. reticulatus, in the spread of spotted fever group rickettsiae in various regions of Europe. The study also focuses on the determinants of the presence of vectors and transmission of rickettsiae, as well as the effects of human infections with these pathogens. The climate changes observed nowadays affect vectors and increase the incidence and spread of tick-borne diseases worldwide. Due to the existing risk of exposure to an increasing number of people, knowledge about the course of these serious diseases and their etiological factors should be disseminated among healthcare professionals as well as in society. There is a great challenge for epidemiological services to provide access to medical and veterinary facilities in order to diagnose and treat rickettsioses. Therefore, the development of a strategy for tick control and the popularisation of knowledge concerning prophylaxis of tick-borne diseases is indispensable.


Assuntos
Vetores Aracnídeos/microbiologia , Dermacentor/microbiologia , Rickettsia/fisiologia , Rickettsiose do Grupo da Febre Maculosa/transmissão , Animais , Europa (Continente) , Humanos , Rickettsiose do Grupo da Febre Maculosa/microbiologia
11.
J Parasitol ; 106(5): 670-674, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33089326

RESUMO

Introduction of exotic tick vectors of bacteria, protozoa, viruses, and filarial parasites into the United States has accelerated in recent years, primarily because of globalization, increased frequency of travel, and a rise in legal and illegal animal trades. We herein report introduction of a live specimen of Amblyomma oblongoguttatum on a human into the United States from Central America, and we review 4 previous similar incidents. This tick species occurs widely in the neotropics, from western and southern Mexico, southwards through Central America, to the northern half of South America. It is a potential vector of bacterial agents of spotted fever group rickettsioses, raising concern that if A. oblongoguttatum ticks become established in this country, they might also be able to carry pathogens of human and veterinary concern. Given the potential for exotic ticks as vectors of numerous pathogens, proper surveillance, interception, and identification of these ticks are vital to protecting human and veterinary health. Rigorous governmental inspections of imported livestock and pet animals at ports of entry and educating human travelers and medical practitioners about the risks should be part of an overall national tick program.


Assuntos
Ixodidae/crescimento & desenvolvimento , Infestações por Carrapato/parasitologia , Abdome/parasitologia , Animais , Connecticut , Costa Rica , DNA/isolamento & purificação , Feminino , Humanos , Ixodidae/genética , Ixodidae/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Viagem
12.
Vector Borne Zoonotic Dis ; 20(8): 566-571, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32744925

RESUMO

Rickettsia species cause rickettsioses, which are zoonotic diseases found worldwide, and are transmitted by arthropods such as lice, fleas, ticks, and mites. In Thailand, flea infestations are common among cats and dogs. This study aimed at determining the exposure to spotted fever group rickettsiae (SFGR) of cats in surrounding areas of Rajabhat Maha Sarakham University, Muang district, Maha Sarakham province and rickettsial infection among cat fleas, Ctenocephalides felis, collected from dogs of the surrounding area of Waeng Noi district, Khon Kaen province. Forty-two cat sera were assessed for IgG antibody titers against SFGR by a group-specific enzyme-linked immunosorbent assay. The prevalence of seroreactive cats was 4.76% (2/42). DNA preparations from 23 individual cat fleas from three dogs were assessed by Rickettsia genus-specific, group-specific, and species-specific quantitative real-time PCR (qPCR) assays. Positive results were confirmed by ompB gene fragment sequencing. Twenty-one of 23 cat fleas were positive for Rickettsia asembonensis, and the other two DNA preparations were negative for rickettsial DNA. This study's finding indicates that companion cats and dogs in Northeast Thailand are exposed to SFGR and that exposure may be due to infection with R. asembonensis, an organism known to infect humans, monkeys, and dogs. Clinicians for humans and animals in Northeast Thailand should be aware of rickettsial infections among their patients.


Assuntos
Doenças do Gato/microbiologia , Infestações por Pulgas/veterinária , Rickettsia/isolamento & purificação , Sifonápteros/microbiologia , Rickettsiose do Grupo da Febre Maculosa/veterinária , Animais , Doenças do Gato/epidemiologia , Gatos , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Tailândia/epidemiologia
13.
Pathogens ; 9(8)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748891

RESUMO

Background: Ticks transmit a plethora of pathogens of zoonotic implications. Their distribution, diversity and the pathogens they transmit differ from one ecological location to another. Rickettsia africae is the agent of African tick bite fever found in South Africa, a zoonotic infection that is frequently reported among travelers who have visited many sub-Saharan African countries where the pathogen is prevalent. Methods: Ticks were collected from domestic animals in Raymond Nkandla Municipality, Eastern Cape, South Africa. The ticks were identified morphologically prior to DNA extraction followed by molecular identification of randomly selected ticks from the morphologically delineated groups. To assess for the presence of tick-borne pathogens belonging to Rickettsia spp. by PCR (polymerase chain reaction), we used specific primer pairs targeting the gltA, ompA and ompB genes. The selected amplified ticks, all positive ompB and forty three ompA amplicons were sequenced in a commercial sequencing facility. The obtained nucleotide sequences were edited and subjected to BLASTn for homology search and phylogenetic analyses were performed with MEGA 7 Version for genetic relationships with curated reference sequences in GenBank. Results: A total of 953 ticks collected in the study were delineated into three genera consisting of Amblyomma, Rhipicephalus and Hyalomma in decreasing order of abundance. The presence of rickettsial DNA was detected in 60/953 (6.3%) from the three genera of ticks screened. Genetic analyses of the DNA sequences obtained showed that they have phylogenetic relationship to members of the spotted fever group rickettsiae with R. africae, being the predominant SFGR (spotted fever group rickettsiae) detected in the screened ticks. Conclusion: This report shows that R. africae is the predominant spotted fever group rickettsiae in ticks collected from domestic animals in the study area and the human health impacts are not known.

14.
Ticks Tick Borne Dis ; 11(4): 101453, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32439385

RESUMO

The lone star tick (Amblyomma americanum) is the most common and abundant human-biting tick in the southeastern United States where spotted fever rickettsioses frequently occur. However, the role of this tick in transmitting and maintaining pathogenic and non-pathogenic spotted fever group rickettsiae (SFGR) remains poorly defined. This is partially due to the high prevalence and abundance of Rickettsia amblyommatis in most populations of A. americanum. Many molecular assays commonly employed to detect rickettsiae use PCR primers that target highly conserved regions in the SFGR so low abundance rickettsia may not be detected when R. amblyommatis is present. It is costly and inefficient to test for low abundance rickettsial agents with multiple individual specific assays even when they are multiplexed, as most samples will be negative. Real time PCR assays may also be hampered by inadequate limits of detection (LODs) for low abundance agents. We exploited the absence of an otherwise relatively SFGR-conserved genome region in R. amblyommatis to design a hemi-nested PCR-assay which has a sensitivity of 10 copies in detecting the presence of most SFGR, but not R. amblyommatis in DNA of infected lone star ticks. This deletion is conserved in 21 isolates of R. amblyommatis obtained from multiple states. We demonstrated the assay's utility by detecting a pathogenic SFGR, Rickettsia parkeri, in 15/50 (30 %) of field collected A. americanum ticks that were previously screened with conventional assays and found to be positive for R. amblyommatis. These co-infected ticks included 1 questing female, 6 questing nymphs, and 8 attached males. The high prevalence of R. parkeri among host-attached ticks may be due to several variables and does not necessarily reflect the risk of disease transmission from attached ticks to vertebrate hosts. This novel assay can provide accurate estimates of the prevalence of less common SFGR in A. americanum and thus improve our understanding of the role of this tick in the maintenance and transmission of the SFGR commonly responsible for human rickettsioses.


Assuntos
Amblyomma/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Rickettsia/isolamento & purificação , Amblyomma/crescimento & desenvolvimento , Animais , Feminino , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/instrumentação
15.
Emerg Infect Dis ; 26(5): 985-988, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32310072

RESUMO

In 2015, we evaluated 221 patients with undifferentiated fever and tick bite or animal exposure in Xinyang, China, for Rickettsia infection. Three with mild disease were infected with Candidatus R. xinyangensis, which clustered with R. fournieri and R. vini in phylogenetic analyses. Field investigations suggest Haemaphysalis longicornis ticks might be involved in transmission.


Assuntos
Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , China/epidemiologia , Humanos , Filogenia , Rickettsia/genética , Rickettsiose do Grupo da Febre Maculosa/diagnóstico , Rickettsiose do Grupo da Febre Maculosa/epidemiologia
16.
Transbound Emerg Dis ; 67 Suppl 2: 36-43, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31231971

RESUMO

Spotted fever group rickettsiae (SFGR) and Coxiella burnetii are intracellular bacteria that cause potentially life-threatening tick-borne rickettsioses and Q fever respectively. Sao Tome and Principe (STP), small islands located in the Gulf of Guinea, recently experienced a dramatic reduction in the incidence of malaria owing to international collaborative efforts. However, unexplained febrile illnesses persist. A One Health approach was adopted to investigate exposure to SFGR and C. burnetii in humans and examine the diversity of these bacteria in ticks parasitizing domestic ruminants. A cross-sectional human serological study was conducted in Agua Grande district in Sao Tome Island from January to March 2016, and ticks were collected from farmed domestic ruminants in 2012 and 2016. In total, 240 individuals varying in age were randomly screened for exposure to SFGR and C. burnetii by indirect immunofluorescence assay. Twenty of 240 individuals (8.3%) were seropositive for SFGR (4 for Rickettsia africae and 16 for R. conorii) and 16 (6.7%) were seropositive for C. burnetii. Amblyomma astrion were collected exclusively in 2012, as were A. variegatum in 2016 and Rickettsia spp. were detected in 22/42 (52.4%) and 49/60 (81.7%) respectively. Sequence analysis of multiple gene targets from Rickettsia spp. detected in ticks suggests the presence of a single divergent R. africae strain (Sao Tome). While no ticks were found positive for C. burnetii, Coxiella-like endosymbionts were detected in nearly all ticks. This is the first study in STP to provide serological evidence in humans of SFGR and C. burnetii and additional molecular evidence in ticks for SFGR, which may be responsible for some of the unexplained febrile illnesses that persist despite the control of malaria. Future epidemiological studies are needed to confirm the occurrence and risk factors associated with SFG rickettsioses and Q fever in both humans and animals.


Assuntos
Coxiella burnetii/isolamento & purificação , Febre Q/epidemiologia , Rickettsia/isolamento & purificação , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Adolescente , Adulto , Idoso , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Bovinos , Criança , Pré-Escolar , Coxiella burnetii/genética , Coxiella burnetii/imunologia , Estudos Transversais , DNA Bacteriano/genética , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Cabras , Humanos , Lactente , Recém-Nascido , Ilhas , Masculino , Pessoa de Meia-Idade , Biologia Molecular , Saúde Única , Reação em Cadeia da Polimerase , Febre Q/veterinária , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Rickettsia/genética , Rickettsia/imunologia , São Tomé e Príncipe/epidemiologia , Análise de Sequência de DNA/veterinária , Estudos Soroepidemiológicos , Rickettsiose do Grupo da Febre Maculosa/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Carrapatos
17.
Ticks Tick Borne Dis ; 10(4): 924-928, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31080140

RESUMO

Livestock and their ectoparasites are involved in the epidemiology of several zoonotic diseases. Studies regarding the molecular detection of infectious agents in ticks from Northwestern Algeria are scarce. Thus, the presence of spotted fever group Rickettsia spp., Anaplasmataceae microorganisms and Coxiella burnetii was investigated in ticks collected from ruminants in Sidi Bel Abbes and Saida provinces. Rickettsia aeschlimannii was detected in one Hyalomma excavatum pool and one H. marginatum pool. Moreover, 'Candidatus Rickettsia barbariae' was found in one H. excavatum and six Rhipicephalus bursa pools. Lastly, Coxiella burnetii was amplified in two H. excavatum and two R. bursa pools. No Anaplasmataceae bacterium was detected. This study demonstrates the presence of the tick-associated microorganism 'Candidatus R. barbariae' in the North of Africa, and corroborates the presence of the zoonotic pathogens R. aeschlimannii and C. burnetii in Algeria.


Assuntos
Coxiella burnetii/genética , Ixodidae/microbiologia , Gado/parasitologia , Rickettsia/genética , Infestações por Carrapato/veterinária , Argélia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Coxiella burnetii/isolamento & purificação , DNA Bacteriano/genética , Feminino , Ixodidae/genética , Gado/microbiologia , Filogenia , Reação em Cadeia da Polimerase , Rickettsia/isolamento & purificação , Ruminantes/microbiologia , Ruminantes/parasitologia
18.
Ticks Tick Borne Dis ; 10(4): 862-867, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31014939

RESUMO

Ticks and ear biopsies were collected from wild small rodents in 2011 and 2012 in the northern Apennines (Italy), up to 1650 m above sea level. Apodemus spp. (n = 83) and Myodes glareolus (n = 22) were infested by Ixodes ricinus (192 larvae and two nymphs), Dermacentor marginatus (179 larvae and 29 nymphs), and Ixodes trianguliceps (three larvae and two nymphs). We detected several Borrelia burgdorferi sensu lato (s.l.) genospecies (B. afzelii, B. burgdorferi sensu stricto, B. garinii, B. lusitaniae, B. valaisiana) in I. ricinus and skin biopsies. The most common genospecies found in I. ricinus was B. valaisiana, while it was B. lusitaniae in tissues. Spotted fever group (SFG) rickettsiae (Rickettsia monacensis, R. slovaca and R. raoultii) infected I. ricinus, D. marginatus and rodent tissues. Rickettsia slovaca was the Rickettsia species most frequently found in our samples. Coinfections by B. burgdorferi s.l. and SFG rickettsiae indicate an overlap of transmission cycles and potential risk for humans to be infected by multiple pathogens, resulting in more severe symptoms. The findings of B. lusitaniae and R. slovaca in bank voles, and of B. valaisiana in small rodents, open new questions about host-pathogen interactions. In addition, our results highlight the importance of small rodents as data sources for studying tick-borne pathogens.


Assuntos
Reservatórios de Doenças/microbiologia , Doença de Lyme/epidemiologia , Roedores/parasitologia , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Carrapatos/microbiologia , Altitude , Animais , Biópsia , Borrelia burgdorferi/isolamento & purificação , Grupo Borrelia Burgdorferi , Dermacentor/microbiologia , Feminino , Itália/epidemiologia , Ixodes/microbiologia , Larva/microbiologia , Masculino , Ninfa/microbiologia , Rickettsia/isolamento & purificação , Pele/parasitologia , Pele/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-30961819

RESUMO

Wild animals fulfill an important mission in the ecology of tick-borne diseases as both suitable hosts to tick vectors and reservoirs of the pathogens. However, current data regarding the role of wild animals in the ecology of tick-borne pathogens is insufficient and more investigations are required. In this study, we investigated tick-borne bacterial pathogens in wild boar, hare, and fox and their ticks in Turkey. A total of 102 tick pools comprised of 445 ticks and blood samples were analyzed for the presence of bacterial DNA by PCRs targeted rickettsial gltA and ompA genes, 5S-23S rDNA gene for Borrelia spp., and msp4 gene for Anaplasma spp. As a result of PCR and sequence analyses, three pathogenic spotted fever group (SFG) rickettsiae, two SFG rickettsiae with unknown pathogenicity and one pathogenic Borrelia burgdorferi sensu lato were detected in samples obtained from wild animals. Rickettsia slovaca was detected in ticks (13.7% of tick pools) collected from wild boars and blood of a wild boar. In addition, the presences of R. hoogstraalii (19.6% of tick pools), R. aeschlimannii (5.8% of tick pools), R. sibirica subsp. mongolitimonae (1.9% of tick pools) and Candidatus R. goldwasserii (0.9% of tick pools) were detected in ticks collected from wild animals. Furthermore, B. burgdorferi sensu stricto was detected in a tick pool collected from a wild boar. This is the first report on the presence of Candidatus R. goldwasserii in Turkey. Consequently, this study shows that pathogenic Rickettsia and Borrelia species are circulating in Turkish wildlife and these pathogens can pose a threat to human health. Also, it has been determined that the investigated wild animals play a role as maintenance host for vector ticks; therefore, these animals must also be considered in the ecology of the mentioned pathogens.


Assuntos
Anaplasma/isolamento & purificação , Borrelia burgdorferi/isolamento & purificação , Doença de Lyme/epidemiologia , Infecções por Rickettsia/epidemiologia , Rickettsia/isolamento & purificação , Doenças Transmitidas por Carrapatos/veterinária , Carrapatos/microbiologia , Anaplasma/genética , Animais , Animais Selvagens/microbiologia , Animais Selvagens/parasitologia , Borrelia burgdorferi/genética , DNA Bacteriano/genética , Feminino , Raposas , Doença de Lyme/microbiologia , Doença de Lyme/veterinária , Masculino , Coelhos , Rickettsia/genética , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Sus scrofa , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/transmissão , Turquia/epidemiologia
20.
Emerg Infect Dis ; 25(4): 836-838, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30882330

RESUMO

We report Rickettsia parkeri and Candidatus Rickettsia andeanae in ticks of the Amblyomma maculatum group collected from dogs in Sonora, Mexico. Molecular characterization of these bacteria was accomplished by DNA amplification and sequence analysis of portions of the rickettsial genes gltA, htrA, ompA, and ompB.


Assuntos
Rickettsia , Infestações por Carrapato/epidemiologia , Carrapatos/microbiologia , Animais , Genes Bacterianos , Humanos , México/epidemiologia , Tipagem Molecular , Reação em Cadeia da Polimerase , Rickettsia/classificação , Rickettsia/genética , Rickettsia/isolamento & purificação , Análise de Sequência de DNA
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