RESUMO
The Pacific Coast tick (Dermacentor occidentalis Marx, 1892) is a frequently encountered and commonly reported human-biting tick species that has been recorded from most of California and parts of southwestern Oregon, southcentral Washington, and northwestern Mexico. Although previous investigators have surveyed populations of D. occidentalis for the presence of Rickettsia species across several regions of California, populations of this tick have not been surveyed heretofore for rickettsiae from Baja California, Oregon, or Washington. We evaluated 1,367 host-seeking, D. occidentalis adults collected from 2015 to 2022 by flagging vegetation at multiple sites in Baja California, Mexico, and Oregon and Washington, United States, using genus- and species-specific assays for spotted fever group rickettsiae. DNA of Rickettsia 364D, R. bellii, and R. tillamookensis was not detected in specimens from these regions. DNA of R. rhipicephali was detected in D. occidentalis specimens obtained from Ensenada Municipality in Baja California and southwestern Oregon, but not from Washington. All ompA sequences of R. rhipichephali that were amplified from individual ticks in southwestern Oregon were represented by a single genotype. DNA of the Ixodes pacificus rickettsial endosymbiont was amplified from specimens collected in southwestern Oregon and Klickitat County, Washington; to the best of our knowledge, this Rickettsia species has never been identified in D. occidentalis. Collectively, these data are consistent with a relatively recent introduction of Pacific Coast ticks in the northernmost extension of its recognized range.
Assuntos
Dermacentor , Rickettsia , Animais , Rickettsia/isolamento & purificação , Rickettsia/genética , Dermacentor/microbiologia , Washington , Oregon , Feminino , México , MasculinoRESUMO
Recent research has found that repetitive negative thinking (RNT) is an important transdiagnostic process both in adult and child psychopathology. This finding has led some authors to design content-independent measures of RNT that can be administered across disorders. One of these instruments is the Perseverative Thinking Questionnaire (PTQ) and its version for children (PTQ-C). This study presents the Spanish translation of the PTQ-C and its psychometric analysis in a sample of 1,127 Colombian children and adolescents (8-18 years old). All items obtained good discrimination indexes, and internal consistency was excellent (.93). A cross-validation study was conducted to analyze the factor structure of the PTQ-C, which strongly supported the one-factor structure. Measurement invariances across gender and age-group (8-12 and 13-18 years old) were also found. The PTQ-C scores for older boys were lower than for younger boys, whereas the inverse pattern was found for girls. The PTQ-C showed strong correlations with measures of pathological worry, emotional symptoms, and psychological inflexibility. In conclusion, the Spanish translation of the PTQ-C appears to be a valid and reliable measure of RNT.
Assuntos
Ansiedade , Transtornos Mentais , Adolescente , Adulto , Criança , Colômbia , Feminino , Humanos , Masculino , Psicometria , Inquéritos e QuestionáriosRESUMO
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 DNARESUMO
Rickettsia felis is an emerging human pathogen associated primarily with the cat flea Ctenocephalides felis. In this study, we investigated the presence of Rickettsia felis in C. felis from Guatemala and Costa Rica. Ctenocephalides felis were collected directly from dogs and cats, and analyzed by polymerase chain reaction for Rickettsia-specific fragments of 17-kDa protein, OmpA, and citrate synthase genes. Rickettsia DNA was detected in 64% (55 of 86) and 58% (47 of 81) of flea pools in Guatemala and Costa Rica, respectively. Sequencing of gltA fragments identified R. felis genotype URRWXCal(2) in samples from both countries, and genotype Rf2125 in Costa Rica. This is the first report of R. felis in Guatemala and of genotype Rf2125 in Costa Rica. The extensive presence of this pathogen in countries of Central America stresses the need for increased awareness and diagnosis.
Assuntos
Ctenocephalides/microbiologia , DNA Bacteriano/isolamento & purificação , Infecções por Rickettsia/veterinária , Rickettsia felis/isolamento & purificação , Rickettsia felis/patogenicidade , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Gatos/microbiologia , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Costa Rica/epidemiologia , DNA Bacteriano/genética , Cães/microbiologia , Ectoparasitoses/epidemiologia , Ectoparasitoses/veterinária , Guatemala/epidemiologia , Humanos , Reação em Cadeia da Polimerase , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/transmissãoRESUMO
Circulation of a unique genetic type of Rickettsia rickettsii in ticks of the Rhipicephalus sanguineus complex was detected in Mexicali, Baja California, Mexico. The Mexican R. rickettsii differed from all isolates previously characterized from the endemic regions of Rocky Mountain spotted fever in northern, central, and southern Americas. Rhipicephalus ticks in Mexicali are genetically different from Rh. sanguineus found in the United States.
Assuntos
Rhipicephalus/microbiologia , Rickettsia rickettsii/isolamento & purificação , Animais , DNA Bacteriano/genética , México , Filogenia , Rickettsia rickettsii/genéticaRESUMO
Several outbreaks of Rocky Mountain spotted fever have occurred in recent years in Colombian communities close to the border with Panama. However, little is known about rickettsiae and rickettsial diseases in eastern Panamanian provinces, the Darien Province and the Kuna Yala, located north of the endemic area in Colombia. In 2007, 289 ticks were collected in several towns from dogs, horses, mules, cows, and pigs. DNA was extracted from 124 Dermacentor nitens, 64 Rhipicephalus sanguineus, 43 Amblyomma ovale, 35 A. cajennense, 10 Boophilus microplus, 4 A. oblongoguttatum, and 9 A. cajennense nymphs. SYBR-Green polymerase chain reaction assays targeting a fragment of the OmpA and 16S rRNA genes were used for detection of DNA of the spotted fever group rickettsiae (SFGR) and Anaplasmataceae (Anaplasma and Ehrlichia), respectively. In total, 37.4% ticks were positive for SFGR, including 20.3% R. sanguineus, 27.9% A. ovale, 25.8% D. nitens, 50% B. microplus, 50% A. oblongoguttatum, and 100% A. cajennense. The presence of Rickettsia amblyommii DNA was confirmed by sequencing in A. cajennense, A. oblongoguttatum, A. ovale, B. microplus, and R. sanguineus. DNA of R. rickettsii was only detected in one D. nitens collected from a horse in Santa Fe, Darien Province. Prevalence of Anaplasmataceae varied from 6.3% in R. sanguineus to 26.5% in A. cajennense. DNA of Ehrlichia chaffensis was found in three D. nitens and three A. cajennense from horses. This is the first study providing molecular characterization and prevalence information on SFGR in ticks from these areas and thus will be helpful for future evaluations of the risk of rickettsial diseases for individuals living in this region.