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1.
An Acad Bras Cienc ; 95(suppl 3): e20230741, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126386

RESUMO

Numerous Antarctic species are recognized as reservoirs for various pathogens, and their migratory behavior allows them to reach the Brazilian coast, potentially contributing to the emergence and circulation of new infectious diseases. To address the potential zoonotic risks, we conducted surveillance of influenza A virus (IAV) and coronaviruses (CoVs) in the Antarctic Peninsula, specifically focusing on different bird and mammal species in the region. During the summer of 2021/2022, as part of the Brazilian Antarctic Expedition, we collected and examined a total of 315 fecal samples to target these respiratory viruses. Although we did not detect the viruses of interest during this particular expedition, previous research conducted by our team has shown the presence of the H11N2 subtype of influenza A virus in penguin fecal samples from the same region. Given the continuous emergence of new viral strains worldwide, it is crucial to maintain active surveillance in the area, contributing to strengthening integrated One Health surveillance efforts.


Assuntos
Infecções por Coronavirus , Vírus da Influenza A , Influenza Aviária , Spheniscidae , Animais , Regiões Antárticas , Conduta Expectante , Influenza Aviária/epidemiologia , Filogenia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Mamíferos
2.
BMC Oral Health ; 23(1): 696, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37759210

RESUMO

BACKGROUND: Early studies have highlighted the possible development of dysgeusia and anosmia in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and these manifestations should be considered a potential indication of coronavirus disease 19 (COVID-19). As potential contributors to these symptoms, dentists should perform careful oral and oropharyngeal examinations and document suspicious oral lesions in patients with COVID-19, especially in those who complain of loss of taste and smell. The study's objective was to assess the prevalence of oral manifestations among ambulatory unvaccinated symptomatic patients with suspected COVID-19 during the acute phase of the disease. METHODS: This cross-sectional study evaluated oral manifestations in adults (aged ≥ 18 years) with suspected and confirmed SARS-CoV-2 infection. Chi-square and Fisher's exact tests were used to compare data between the groups (rRT-PCR-positive and rRT-PCR-negative patients). RESULTS: One hundred thirty-six participants were included. Most were female (n = 79; 58.1%), with a mean age of 39.53 (± 14.17) years. Of these, 54 (39.7%) had a positive rRT-PCR test, and 82 (60.3%) had negative rRT-PCR results. Oral manifestations were observed in 40 participants (74.1%) in the rRT-PCR-positive group and 67 participants (81.7%) in the rRT-PCR-negative group. The most common oral manifestations were xerostomia (n = 85; 62.5%) and dysgeusia/ageusia (n = 57; 41.9%). Different rates of gingivitis (n = 12; 22.2% vs. n = 5; 6.1%; p = 0.005) and halitosis (n = 7; 13.0% vs. n = 1; 1.2%; p = 0.007) were observed between the rRT-PCR-positive and -negative groups, respectively. Mouth ulcers, glossitis, tongue coating, and petechiae were reported in both groups without significant differences. CONCLUSIONS: A high prevalence of oral manifestations was observed in symptomatic patients with suspected or confirmed COVID-19. CLINICAL RELEVANCE: This study highlights the importance of routine oral examinations by dentists as part of the multidisciplinary care of COVID-19 patients.


Assuntos
COVID-19 , Adulto , Humanos , Feminino , Masculino , COVID-19/complicações , SARS-CoV-2 , Estudos Transversais , Disgeusia/epidemiologia , Disgeusia/etiologia , Disgeusia/diagnóstico , Reação em Cadeia da Polimerase
4.
Sci Rep ; 13(1): 7306, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147348

RESUMO

The rapid spread of the SARS-CoV-2 Variant of Concern (VOC) Gamma in Amazonas during early 2021 fueled a second large COVID-19 epidemic wave and raised concern about the potential role of reinfections. Very few cases of reinfection associated with the VOC Gamma have been reported to date, and their potential impact on clinical, immunological, and virological parameters remains largely unexplored. Here we describe 25 cases of SARS-CoV-2 reinfection in Brazil. SARS-CoV-2 genomic analysis confirmed that individuals were primo-infected with distinct viral lineages between March and December 2020 (B.1.1, B.1.1.28, B.1.1.33, B.1.195, and P.2) and reinfected with the VOC Gamma between 3 to 12 months after primo-infection. We found a similar mean cycle threshold (Ct) value and limited intra-host viral diversity in both primo-infection and reinfection samples. Sera of 14 patients tested 10-75 days after reinfection displayed detectable neutralizing antibodies (NAb) titers against SARS-CoV-2 variants that circulated before (B.1.*), during (Gamma), and after (Delta and Omicron) the second epidemic wave in Brazil. All individuals had milder or no symptoms after reinfection, and none required hospitalization. These findings demonstrate that individuals reinfected with the VOC Gamma may display relatively high RNA viral loads at the upper respiratory tract after reinfection, thus contributing to onward viral transmissions. Despite this, our study points to a low overall risk of severe Gamma reinfections, supporting that the abrupt increase in hospital admissions and deaths observed in Amazonas and other Brazilian states during the Gamma wave was mostly driven by primary infections. Our findings also indicate that most individuals analyzed developed a high anti-SARS-CoV-2 NAb response after reinfection that may provide some protection against reinfection or disease by different SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Brasil/epidemiologia , COVID-19/epidemiologia , Diversidade de Anticorpos , Raios gama , Reinfecção , Gravidade do Paciente
5.
BMC Infect Dis ; 23(1): 295, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147601

RESUMO

BACKGROUND: While nasopharyngeal (NP) swabs are considered the gold standard for severe acute respiratory coronavirus 2 (SARS-CoV-2) real-time reverse transcriptase-polymerase chain reaction (RT-PCR) detection, several studies have shown that saliva is an alternative specimen for COVID-19 diagnosis and screening. METHODS: To analyze the utility of saliva for the diagnosis of COVID-19 during the circulation of the Omicron variant, participants were enrolled in an ongoing cohort designed to assess the natural history of SARS-CoV-2 infection in adults and children. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Cohen's kappa coefficient were calculated to assess diagnostic performance. RESULTS: Overall, 818 samples were collected from 365 outpatients from January 3 to February 2, 2022. The median age was 32.8 years (range: 3-94 years). RT-PCR for SARS-CoV-2 was confirmed in 97/121 symptomatic patients (80.2%) and 62/244 (25.4%) asymptomatic patients. Substantial agreement between saliva and combined nasopharyngeal/oropharyngeal samples was observed with a Cohen's kappa value of 0.74 [95% confidence interval (CI): 0.67-0.81]. Sensitivity was 77% (95% CI: 70.9-82.2), specificity 95% (95% CI: 91.9-97), PPV 89.8% (95% CI: 83.1-94.4), NPV 87.9% (95% CI: 83.6-91.5), and accuracy 88.5% (95% CI: 85.0-91.4). Sensitivity was higher among samples collected from symptomatic children aged three years and older and adolescents [84% (95% CI: 70.5-92)] with a Cohen's kappa value of 0.63 (95% CI: 0.35-0.91). CONCLUSIONS: Saliva is a reliable fluid for detecting SARS-CoV-2, especially in symptomatic children and adolescents during the circulation of the Omicron variant.


Assuntos
COVID-19 , Pacientes Ambulatoriais , Adolescente , Adulto , Criança , Humanos , Saliva , Teste para COVID-19 , SARS-CoV-2/genética , COVID-19/diagnóstico , Nasofaringe , Manejo de Espécimes
6.
Acta Parasitol ; 67(4): 1657-1666, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36125653

RESUMO

PURPOSE: Small mammals are important reservoirs of ticks and their pathogens in nature. However, studies reporting these associations are still rare in Brazil. In the present study, we investigated the presence of Rickettsia DNA in ticks parasitizing rodents and marsupials captured in different areas throughout the Atlantic rainforest biome, Bahia, Northeastern (NE), Brazil. METHODS: The study was conducted in five municipalities within of the Atlantic Forest biome, Bahia state, in NE Brazil. Two campaigns were done in each municipality. For host captures Sherman and Tomahawk traps were used, and pitfall traps. After being captured, the hosts were anesthetized and their entire body examined for ticks. When ticks were detected, they were manually removed and stored in eppendorf tubes (1.5 ml) containing absolute PA ethanol for future laboratory analysis (identification of ticks and detection of Rickettsia spp.). RESULTS: A total of 609 mammals were captured. Overall, 208 ticks of the genus Amblyomma and Ixodes were collected: A. ovale, I. loricatus and A. varium. Rickettsia DNA was detected in A. ovale and it was 99-100% of identity to the sequence deposited in GenBank as Rickettsia parkeri strain Atlantica rainforest. CONCLUSION: These results suggest that R. parkeri strain Atlantic rainforest occurs in the region, and A. ovale is likely the vector.


Assuntos
Ixodidae , Rickettsia , Carrapatos , Animais , Brasil/epidemiologia , Ixodidae/microbiologia , Floresta Úmida , Rickettsia/genética , Roedores
7.
Microbiol Spectr ; 10(5): e0142722, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36121294

RESUMO

Influenza A viruses infect a range of host species, including a large variety of mammals and more than a hundred species of birds. A total of 95 avian fecal samples were collected from penguin colonies in the South Shetland Islands, close to the Antarctic Peninsula, and tested by reverse transcription-PCR (RT-PCR) to detect avian influenza viruses (AIVs). Five out of seven samples collected from Penguin Island were positive for AIVs. Analysis of the genomes recovered from four samples revealed the detection of influenza A(H11N2) virus in fecal samples from Adélie penguins (Pygoscelis adeliae) and from a colony of chinstrap penguins (Pygoscelis antarcticus). Bayesian phylogeographic analysis revealed the clustering of all currently available H11N2 samples from Antarctica's avifauna in a single cluster that emerged at least in the early 2010s, suggesting its continued circulation on the continent. Our results reinforce the need for continuous surveillance of avian influenza on the Antarctic continent. IMPORTANCE Although wild birds play a role in the transmission and ecology of avian influenza viruses (AIVs) across the globe, there are significant gaps in our understanding of the worldwide distribution of these viruses in polar environments. In this study, using molecular analysis and full-genome sequencing, we describe the detection of distinct influenza A(H11N2) viruses in fecal samples of penguins in the Southern Shetland Islands, Antarctica. We emphasize the need for virus monitoring as AIVs may have implications for the health of endemic fauna and the potential risk of the introduction of highly pathogenic AIVs to the continent.


Assuntos
Vírus da Influenza A , Influenza Aviária , Influenza Humana , Spheniscidae , Animais , Humanos , Regiões Antárticas , Teorema de Bayes , Influenza Aviária/epidemiologia , Vírus da Influenza A/genética , Mamíferos
8.
Int J Infect Dis ; 114: 58-61, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34757006

RESUMO

We describe a case of prolonged COVID-19 caused by the SARS-CoV-2 Gamma variant in a fully vaccinated healthcare worker, 387 days after an infection caused by lineage B.1.1.33. Infections were confirmed by whole-genome sequencing and corroborated by the detection of neutralizing antibodies in convalescent serum samples. Considering the permanent exposure of this healthcare worker to SARS-CoV-2, the waning immunity after the first infection, the low efficacy of the inactivated vaccine at preventing COVID-19, the immune escape of the Gamma variant (VOC), and the burden of post-COVID syndrome, this individual would have benefited from an additional dose of a heterologous vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil , COVID-19/complicações , COVID-19/terapia , Humanos , Imunização Passiva , Reinfecção , Vacinas de Produtos Inativados , Soroterapia para COVID-19 , Síndrome de COVID-19 Pós-Aguda
9.
Ticks Tick Borne Dis ; 13(2): 101891, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34942561

RESUMO

Wild animals are of considerable importance in the ecology of infectious agents, as they can function as hosts and even as possible vectors. In this study, DNA from Rickettsia spp. was detected on ticks and fragments of skin collected from wild coatis with synanthropic habits in the Iguaçu National Park (INP) in the state of Paraná in southern Brazil. Testing was carried out on a total of 566 ticks, comprising Amblyomma spp. larvae, nymphs of Haemaphysalis juxtakochi, Amblyomma brasiliense, Amblyomma coelebs, and adults of Amblyomma ovale. The samples were tested by polymerase chain reaction (PCR) by amplifying htrA, gltA, ompA, and ompB gene fragments to detect Rickettsia spp. A fragment of each positive sample was sequenced in both directions, submitted to Genbank for a homology search, and also used for phylogenetic analyses. Samples of A. coelebs (1.90%, 8/420), A. ovale (13%, 6/45), and ring-tailed coati skin (1%, 1/75) amplified Rickettsia spp. DNA. Through sequencing, Rickettsia bellii was observed in A. ovale, Rickettsia amblyommatis in A. coelebs, while Rickettsia rhipicephali was detected in the skin samples. Wild ring-tailed coatis with synanthropic habits in the INP and their ticks are infected by Rickettsia spp., and associations with new hosts have been described.


Assuntos
Ixodidae , Procyonidae , Rickettsia , Carrapatos , Animais , Brasil/epidemiologia , Ixodidae/microbiologia , Parques Recreativos , Filogenia , Floresta Úmida , Rickettsia/genética
10.
PLoS One ; 16(4): e0250853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909706

RESUMO

BACKGROUND: Infection by SARS-CoV-2 in domestic animals has been related to close contact with humans diagnosed with COVID-19. Objectives: To assess the exposure, infection, and persistence by SARS-CoV-2 of dogs and cats living in the same households of humans that tested positive for SARS-CoV-2, and to investigate clinical and laboratory alterations associated with animal infection. METHODS: Animals living with COVID-19 patients were longitudinally followed and had nasopharyngeal/oropharyngeal and rectal swabs collected and tested for SARS-CoV-2. Additionally, blood samples were collected for laboratory analysis, and plaque reduction neutralization test (PRNT90) to investigate specific SARS-CoV-2 antibodies. RESULTS: Between May and October 2020, 39 pets (29 dogs and 10 cats) of 21 patients were investigated. Nine dogs (31%) and four cats (40%) from 10 (47.6%) households were infected with or seropositive for SARS-CoV-2. Animals tested positive from 11 to 51 days after the human index COVID-19 case onset of symptoms. Three dogs tested positive twice within 14, 30, and 31 days apart. SARS-CoV-2 neutralizing antibodies were detected in one dog (3.4%) and two cats (20%). In this study, six out of thirteen animals either infected with or seropositive for SARS-CoV-2 have developed mild but reversible signs of the disease. Using logistic regression analysis, neutering, and sharing bed with the ill owner were associated with pet infection. CONCLUSIONS: The presence and persistence of SARS-CoV-2 infection have been identified in dogs and cats from households with human COVID-19 cases in Rio de Janeiro, Brazil. People with COVID-19 should avoid close contact with their pets during the time of their illness.


Assuntos
COVID-19/epidemiologia , COVID-19/veterinária , Animais de Estimação/virologia , Animais , Animais Domésticos/virologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Brasil/epidemiologia , Doenças do Gato , Gatos , Doenças do Cão , Cães , Estudos Longitudinais , Prevalência , SARS-CoV-2/patogenicidade
11.
PLoS One ; 16(3): e0248578, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33765012

RESUMO

The epidemic of coronavirus disease 2019 (COVID-19), caused by a novel Betacoronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a public health emergency worldwide. Few reports indicate that owned pets from households with at least one human resident that was diagnosed with COVID-19 can be infected by SARS-CoV-2. However, the exposure to SARS-CoV-2 of pets from households with no COVID-19 cases or stray animals remains less assessed. Using real-time reverse transcriptase polymerase chain reaction (RT-PCR) and plaque reduction neutralization test (PRNT90), we investigated the infection and previous exposure of dogs and cats to SARS-CoV-2 during the ongoing COVID-19 epidemic in Rio de Janeiro, Brazil. From June to August 2020, 96 animals were sampled, including 49 cats (40 owned and 9 stray) and 47 dogs (42 owned and 5 stray). Regarding owned pets, 75.6% (62/82) belonged to households with no COVID-19 cases. Samples included serum, and rectal and oropharyngeal swabs. All swabs were negative for SARS-CoV-2 RNA, but serum samples of a stray cat and a stray dog presented neutralizing antibodies for SARS-CoV-2, with PRNT90 titer of 80 and 40, respectively. Serological data presented here suggest that not only owned pets from households with COVID19 cases, but also stray animals are being exposed to SARS-CoV-2 during the COVID-19 pandemic.


Assuntos
Anticorpos Neutralizantes/sangue , SARS-CoV-2/imunologia , Animais , COVID-19/patologia , COVID-19/virologia , Doenças do Gato/patologia , Doenças do Gato/virologia , Gatos , Doenças do Cão/patologia , Doenças do Cão/virologia , Cães , Feminino , Masculino , Orofaringe/virologia , RNA Viral/metabolismo , Reto/virologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
12.
Vet Parasitol Reg Stud Reports ; 21: 100413, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862893

RESUMO

The Brazilian state of Maranhão is located in a transition area of the Amazon and Cerrado biomes, where there is a rich fauna of vertebrates. This study aimed to update the list of the ticks occurring in Maranhão, through a compilation of literature records and examination of three tick collections, plus the addition of unpublished collections of ticks from road-killed animals during recent years. Our results indicate that the tick fauna of Maranhão includes 26 species: seven in the family Argasidae (Antricola guglielmonei, Argas miniatus, Ornithodoros cavernicolous, Ornithodoros hasei, Ornithodoros mimon, Ornithodoros rietcorreai and Ornithodoros rudis); and 19 in the family Ixodidae (Amblyomma auricularium-provisional, Amblyomma cajennense sensu stricto, Amblyomma calcaratum, Amblyomma dissimile, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, Amblyomma oblongoguttatum, Amblyomma ovale, Amblyomma parvum, Amblyomma rotundatum, Amblyomma sculptum, Amblyomma triste, Dermacentor nitens, Ixodes luciae, Haemaphysalis juxtakochi, Rhipicephalus microplus, and Rhipicephalus sanguineus sensu lato). Eleven of the above species are reported for the first time in Maranhão. We consider previous reports of Ornithodoros talaje and Amblyomma pseudoconcolor in Maranhão as misidentification with O. hasei and A. auricularium, respectively. Until 1958, only 11 tick species were reported in Maranhão, with no additional reports until 2009. During 2010-2019, 15 additional species were reported. We also highlight the importance of ticks for public and veterinary health in Maranhão.


Assuntos
Distribuição Animal , Argasidae/fisiologia , Ixodidae/fisiologia , Animais , Argasidae/classificação , Brasil , Ixodidae/classificação , Estudos Retrospectivos
13.
Mem Inst Oswaldo Cruz ; 115: e200232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32965332

RESUMO

Coronavirus disease 2019 (COVID-19) surveillance, in Brazil, initiated shortly after its description, in China. Our aim was to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and additional pathogens in samples from the initial phase of the outbreak in Brazil, from late February to late March. From 707 samples analysed, 29 (4.1%) were SARS-CoV-2 positive. Fever and cough were their most prevalent symptoms. Co-detection of rhinovirus was observed in 2 (6.9%) cases. Additional pathogens were identified in 66.1% of the SARS-CoV-2 negative cases, mainly rhinovirus and influenza A(H1N1)pdm09. Thus, we emphasise the importance of differential diagnosis in COVID-19 suspected cases.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Brasil/epidemiologia , COVID-19 , China , Infecções por Coronavirus/epidemiologia , Diagnóstico Diferencial , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Pandemias , Pneumonia Viral/epidemiologia , Rhinovirus/isolamento & purificação , SARS-CoV-2
14.
Front Microbiol ; 11: 615280, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33679622

RESUMO

A previous study demonstrates that most of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) Brazilian strains fell in three local clades that were introduced from Europe around late February 2020. Here we investigated in more detail the origin of the major and most widely disseminated SARS-CoV-2 Brazilian lineage B.1.1.33. We recovered 190 whole viral genomes collected from 13 Brazilian states from February 29 to April 31, 2020 and combined them with other B.1.1 genomes collected globally. Our genomic survey confirms that lineage B.1.1.33 is responsible for a variable fraction of the community viral transmissions in Brazilian states, ranging from 2% of all SARS-CoV-2 genomes from Pernambuco to 80% of those from Rio de Janeiro. We detected a moderate prevalence (5-18%) of lineage B.1.1.33 in some South American countries and a very low prevalence (<1%) in North America, Europe, and Oceania. Our study reveals that lineage B.1.1.33 evolved from an ancestral clade, here designated B.1.1.33-like, that carries one of the two B.1.1.33 synapomorphic mutations. The B.1.1.33-like lineage may have been introduced from Europe or arose in Brazil in early February 2020 and a few weeks later gave origin to the lineage B.1.1.33. These SARS-CoV-2 lineages probably circulated during February 2020 and reached all Brazilian regions and multiple countries around the world by mid-March, before the implementation of air travel restrictions in Brazil. Our phylodynamic analysis also indicates that public health interventions were partially effective to control the expansion of lineage B.1.1.33 in Rio de Janeiro because its median effective reproductive number (R e ) was drastically reduced by about 66% during March 2020, but failed to bring it to below one. Continuous genomic surveillance of lineage B.1.1.33 might provide valuable information about epidemic dynamics and the effectiveness of public health interventions in some Brazilian states.

15.
Ticks Tick Borne Dis ; 10(5): 981-986, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31109835

RESUMO

Capybaras (Hydrochoerus hydrochaeris Linnaeus, 1766) (Rodentia: Caviidae) are important hosts of Amblyomma ticks (Acari: Ixodidae), which in turn can transmit rickettsiae to humans and animals. However, there is a scarcity of studies about the tick fauna and rickettsial infection in the Amazon region. The present study evaluated rickettsial infection in capybaras and ticks in different areas of the municipality of Rio Branco, state of Acre, in the Western Brazilian Amazon, where rickettsiosis has never been reported. Blood sera from 43 capybaras from four localities in Rio Branco were tested by indirect immunofluorescence assay using Rickettsia rickettsii antigens. Ticks were collected from capybaras and from vegetation as well. Ticks were taxonomically identified to the species level and some of them were tested by PCR, targeting a fragment of the rickettsial gltA gene. Additionally, ticks were tested for bacteria from the genus Borrelia and family Anaplasmatacae. All capybaras submitted to the serological examination were considered non-reactive to R. rickettsii. A total of 410 ticks were collected directly from the capybaras. Amblyomma dubitatum Neumann, 1899 was the most abundant species (82.4%), followed by Amblyomma naponense (Packard, 1869) (14.3%), Amblyomma humerale Koch, 1844 (0.7%), Amblyomma pacae Aragão, 1911 (0.4%), Amblyomma rotundatum Koch 1844 (0.2%) and Amblyomma sp. (1.7%). From the environment 262 ticks were collected: Rhipicephalus microplus (Canestrini, 1888) (88.9%), Dermacentor nitens Neumann, 1897 (9.9%), Amblyomma varium Koch, 1844 (0.7%) and A. rotundatum (0.3%). With the exception of A. humerale, A. rotundatum and R. microplus, all other species are reported here for the first time in the state. Some of the ticks sampled (N = 317) were tested by molecular methods for infection by Rickettsia spp. Rickettsia bellii was identified infecting A. dubitatum and A. rotundatum, while Rickettsia amblyommatis only was found infecting A. humerale and Rickettsia sp. strain Tapirapé was found in A. naponense. This is the first detection of R. bellii and Rickettsia sp. strain Tapirapé in Acre. No Borrelia or Anaplasmataceae were found in the tested ticks. These results add relevant knowledge about the Rickettsia spp. and the acarological fauna in the region of the Western Amazon, and are essential for the maintenance of vigilance about possible pathogens that occur in the state and determination of the risks that they pose to humans and animals that inhabit the region.


Assuntos
Doenças dos Roedores/epidemiologia , Roedores , Rickettsiose do Grupo da Febre Maculosa/veterinária , Infestações por Carrapato/veterinária , Carrapatos/microbiologia , Carrapatos/fisiologia , Anaplasmataceae/isolamento & purificação , Animais , Antígenos de Bactérias/análise , Borrelia/isolamento & purificação , Brasil/epidemiologia , Feminino , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Rickettsia/isolamento & purificação , Rickettsia rickettsii/isolamento & purificação , Doenças dos Roedores/microbiologia , Doenças dos Roedores/parasitologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Carrapatos/classificação
16.
Ticks Tick Borne Dis ; 10(4): 853-861, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30992179

RESUMO

Reliable data on distributional ranges of soft ticks (Argasidae) and assessments of putative tick-borne agents enhance the understanding on tick-associated microorganisms. A total of 96 ticks morphologicaly and molecularly identified as Ornithodoros rietcorreai were collected in Tocantins State, Brazil, using Noireau traps with living bait as CO2 source. Ninety-six ticks (54 nymphs, 32 males, 10 females) with different engorgement degrees were collected. Fourty-seven (48.9%) of them were individually screened by PCR for detecting bacteria of Anaplasmataceae family and genera Rickettsia, and Borrelia. The presence of protozoans of the genus Babesia was assessed as well. Fourty seven ticks were submitted to analysis. Nine ticks (19.1%) yielded sequences for gltA and htrA genes most identical with a series of endosymbiont rickettsiae and Rickettsia bellii, respectively. Upon two ticks (4.2%) we retrieved DNA of a potential new Wolbachia sp., and DNA of a putative novel Hepatozoon was characterized from three (6.4%) specimens. No DNA of Babesia or Borrelia was detected. Remarkably, amplicons of unidentified eukaryotic organisms, most closely related with apicomplexans but also with dinoflagellates (91% of identity after BLAST analyses), were recovered from two ticks (4.2%) using primers designed for Babesia 18S rRNA gene. Our records expand the distribution of O. rietcorreai into Brazilian Cerrado biome and introduce the occurrence of microorganisms in this tick species.


Assuntos
Bactérias/genética , Ornithodoros/microbiologia , Ornithodoros/parasitologia , Filogenia , Anaplasmataceae/genética , Anaplasmataceae/isolamento & purificação , Animais , Babesia/genética , Babesia/isolamento & purificação , Bactérias/isolamento & purificação , Borrelia/genética , Borrelia/isolamento & purificação , Brasil , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Feminino , Geografia , Larva/microbiologia , Masculino , Ninfa/microbiologia , Rickettsia/genética , Rickettsia/isolamento & purificação
17.
Rev. colomb. cienc. pecu ; 31(1): 26-35, ene.-mar. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-978239

RESUMO

Abstract Background: South American birds are known to play a significant role in life cycles of various hard ticks, particularly within Amblyomma genus. However, the tick fauna from the Amazon region has been poorly studied, being limited to very few studies. Objective: To report tick infestations on wild birds captured in a region of the Amazon forest, Acre state, Brazil, and to evaluate rickettsial infection in these ticks. Methods: Wild birds were captured by mist-nets and examined for the presence of ticks, which were all collected and identified to species level by taxonomic keys and/or molecular methods. In addition, part of these ticks was individually tested by PCR targeting portions of three rickettsial genes (gltA, ompA, ompB). Results: Among 1,322 captured birds, 79 individuals (6.0%) were infested by one of the following ticks species: Amblyomma nodosum Neumann, 1899 (72 nymphs), Amblyomma longirostre (Koch, 1844; seven larvae, 13 nymphs), Amblyomma humerale Koch 1844 (four nymphs), Amblyomma geayi Neumann, 1899 (two larvae, two nymphs), and 421 larvae of Amblyomma spp Rickettsia sp strain NOD was detected in 3/26 A. nodosum, and Rickettsia amblyommatis in 5/8 A. longirostre and 1/2 A. geayi ticks tested. Conclusion: This is the first study about ticks parasitizing wild birds in Acre state, adding new host-parasite relationships, new tick species records (A. humerale and A. nodosum) and two rickettsial agents (R amblyommatis and Rickettsia sp strain NOD) for the first time in Acre.


Resumen Antecedentes: En América del Sur, las aves actúan como importantes hospedadores dentro del ciclo biológico de garrapatas del género Amblyomma, que por su parte, se encuentran naturalmente infectadas con rickettsias patógenas. Aunque la diversidad de aves en esta región es alta, el conocimiento de la fauna de garrapatas asociadas es aún escaso. Objetivo: Reportar la fauna de garrapatas asociadas a aves presentes en la Amazonía, estado de Acre, Brasil, y evaluar en éstas infección por Rickettsia. Métodos: Las aves fueron capturadas con redes de niebla y examinadas en busca de garrapatas, las que a su vez fueron identificadas por medio de claves taxonómicas y métodos moleculares. Parte de estas garrapatas fueron individualmente sometidas a PCR convencional en busca de fragmentos de tres genes rickettsiales (gltA, ompA, ompB). Resultados: De un total de 1.322 aves capturadas, 79 (6,0%) se encontraron parasitadas con alguna de las siguientes especies de garrapatas: Amblyomma nodosum Neumann, 1899 (72 ninfas), Amblyomma longirostre (Koch, 1844; siete larvas, 13 ninfas), Amblyomma humerale Koch 1844 (cuatro ninfas), Amblyomma geayi Neumann, 1899 (dos larvas, dos ninfas) y 421 larvas de Amblyomma spp Rickettsia sp cepa NOD fue detectada en 3/26 A. nodosum y Rickettsia amblyommatis en 5/8 A. longirostre, así como también en 1/2 A. geayi analizadas. Conclusión: Este es el primer estudio sobre garrapatas parásitas de aves desarrollado en el estado de Acre. Además, se reportan nuevas relaciones parásito-hospedador, nuevos registros para dos especies de garrapatas (A. humerale y A. nodosum) y dos rickettsias (R. amblyommatis y Rickettsia sp cepa NOD) por primera vez en Acre.


Resumo Antecedentes: Aves sul-americanas são conhecidas por desempenhar um papel significativo no ciclo de vida de várias espécies de ixodídeos, particularmente dentro do gênero Amblyomma. No entanto, a ixodofauna da região amazônica tem sido pouco estudada, sendo limitada apenas a alguns estudos. Objetivo: Relatar as infestações de carrapatos em aves silvestres capturadas na região de floresta amazônica, Acre, Brasil, e avaliar as infecções por riquétsias. Métodos: As aves silvestres foram capturadas por redes de neblina e examinadas para a presença de carrapatos, que foram coletados e identificados até espécies, utilizando chaves taxonômicas e/ou métodos moleculares. Além disso, uma parte desses carrapatos foram testados individualmente pela PCR para a pesquisa de fragmentos de três genes de riquétsias (gltA, ompA, ompB). Resultados: Entre as 1.322 aves capturadas, 79 indivíduos (6,0%) estavam infestados pelas seguintes espécies de carrapatos: Amblyomma nodosum Neumann, 1899 (72 ninfas), Amblyomma longirostre (Koch, 1844; sete larvas, 13 ninfas), Amblyomma humerale Koch 1844 (quatro ninfas), Amblyomma geayi Neumann, 1899 (duas larvas, duas ninfas) e 421 larvas de Amblyomma spp Rickettsia sp cepa NOD foi detectada em 3/26 A. nodosum e Rickettsia amblyommatis em 5/8 A. longirostre e 1/2 A. geayi dos carrapatos testados. Conclusão: Este é o primeiro estudo de carrapatos parasitando aves silvestres no estado do Acre, demostrando novas relações parasita-hospedeiro e registros inéditos de espécies de carrapatos (A. humerale e A. nodosum) e riquétsias (R. amblyommatis e Rickettsia sp strain NOD) para o Acre.

18.
Ticks Tick Borne Dis ; 8(4): 646-656, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28457822

RESUMO

New genotypes of Anaplasmataceae agents have been detected in wild carnivores, birds and deer in Brazil. The present work aimed to investigate the presence of Ehrlichia and Anaplasma species in rodents sampled in Brazil. Additionally, a newly designed quantitative 5' nuclease real-time multiplex PCR for Ehrlichia and Anaplasma spp. detection based on groEL gene amplification was designed, showing high specificity and sensitivity (10 groEL fragment copy/µL). Between 2000 and 2011, different rodent species [n=60] were trapped in 5 Brazilian biomes. Among 458 rodent spleen samples, 0.4% (2/458) and 2.4% (11/458) were positive for Ehrlichia and Anaplasma spp., respectively. Of 458 samples, 2.0% (9/458) and 1.1% (5/458) were positive for Anaplasma sp. and Ehrlichia sp., respectively, using conventional 16S rRNA PCR assays. Maximum Likelihood phylogenetic analyse based on a small region of 16S rRNA genes positioned the Anaplasma genotypes in rodents near Anaplasma phagocytophilum or Anaplasma marginale and Anaplasma odocoilei isolates. Ehrlichia genotypes were closely related to E. canis. There was a low occurrence of Anaplasma and Ehrlichia in wild and synanthropic rodents in Brazil, suggesting the circulation of new genotypes of these agents in rodents in the studied areas.


Assuntos
Anaplasma/isolamento & purificação , Proteínas de Bactérias/genética , Chaperonina 60/genética , Ehrlichia/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Roedores/epidemiologia , Roedores , Anaplasma/genética , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Animais , Brasil/epidemiologia , Ehrlichia/genética , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Ehrlichiose/veterinária , Prevalência , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Doenças dos Roedores/microbiologia
19.
Ticks Tick Borne Dis ; 8(1): 90-98, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769655

RESUMO

Information about tick fauna and monitoring of pathogen prevalences in ticks (Acari: Ixodidae) in various habitat types can enhance knowledge about the epidemiology of tick-borne pathogens in Brazil. This work shows the results of a study of tick parasitism of wild rodents and marsupials collected in seven localities in the southern part of Brazil, within Atlantic Forest and Cerrado biomes. A total of 61 ticks were collected from small mammals, and after identification to the species level, the ticks were individually tested for the presence of bacteria of the genera Rickettsia, Borrelia, family Anaplasmataceae, and protozoa of the genus Babesia. The following species of ticks were found: Amblyomma ovale Koch, 1844, Amblyomma dubitatum Neumann, 1899, Amblyomma fuscum Neumann, 1907, Ixodes aragaoi Fonseca, 1935, Ixodes fuscipes Koch, 1844, Ixodes loricatus Neumann, 1899, and Ixodes schulzei Aragão and Fonseca, 1951. Among tested ticks, no DNA of Borrelia, Babesia or Anaplasmataceae was detected. Two nymphs of A. ovale were found infected with Rickettsia bellii and four nymphs of I. aragaoi with Rickettsia sp., genetically close to Rickettsia monacensis, Rickettsia tamurae and the endosymbiont Rickettsia spp., previously found in various Ixodidae. In one nymph of A. fuscum, DNA of a novel Hepatozoon sp. was found. Additionally we provide novel tick-host associations.


Assuntos
Babesia/isolamento & purificação , Bactérias/isolamento & purificação , Ixodidae/microbiologia , Marsupiais/parasitologia , Roedores/parasitologia , Infestações por Carrapato/veterinária , Animais , Babesia/genética , Babesiose/epidemiologia , Babesiose/parasitologia , Bactérias/genética , Brasil/epidemiologia , Ixodidae/classificação , Ninfa/classificação , Filogenia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
20.
J Med Entomol ; 53(4): 843-850, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27230435

RESUMO

The hard tick Amblyomma aureolatum (Pallas) is a vector of the bacterium Rickettsia rickettsii, the etiologic agent of Brazilian spotted fever (BSF) in parts of Brazil. Despite its wide distribution in southeastern South America and its public health importance, there is no information about genetic variation of this species that might help to understand the epidemiology of BSF. Using data from eight microsatellite markers and ticks from six localities, we used a population genetics approach to test the hypothesis that tick populations from areas with the presence of R. rickettsii are genetically different from ticks from areas without R. rickettsii Contrary to expectations, we found low genetic structure between studied regions. Thus, the presence of R. rickettsii in the specific area is more likely correlated with ecological and the environmental conditions or due to unknown gene coding regions of A. aureolatum genome that would be related to R. rickettsii infection resistance.


Assuntos
Variação Genética , Ixodidae/fisiologia , Repetições de Microssatélites , Animais , Brasil , Ixodidae/genética , Ixodidae/microbiologia , Dinâmica Populacional , Rickettsia rickettsii/fisiologia
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