RESUMEN
We determined prevalence of Rickettsia spp. in 172 ticks of the Amblyomma maculatum group collected from 16 urban sites in Oklahoma City, Oklahoma, USA, during 2017 and 2018. Most ticks (59.3%) were collected from 1 site; 4 (2.3%) were infected with Rickettsia parkeri and 118 (68.6%) with Candidatus Rickettsia andeanae.
Asunto(s)
Amblyomma/microbiología , Infecciones por Rickettsia/prevención & control , Rickettsia/aislamiento & purificación , Animales , Demografía , Humanos , Oklahoma/epidemiología , Prevalencia , Población UrbanaRESUMEN
Aedes aegypti is an important subtropical vector species and is predicted to have a limited year-round distribution in the southern United States. Collection of the species has not been officially verified in Oklahoma since 1940. Adult mosquitoes were collected in 42 sites across 7 different cities in Oklahoma using 3 different mosquito traps between May and September 2016. Between July and September 2016, 88 Ae. aegypti adults were collected at 18 different sites in 4 different cities across southern Oklahoma. Centers for Disease Control and Prevention mini light traps baited with CO2 attracted the highest numbers of Ae. aegypti individuals compared to Biogents (BG)-Sentinel® traps baited with Biogents (BG)-lure and octenol and Centers for Disease Control and Prevention gravid traps baited with Bermuda grass-infused water. The discovery of Ae. aegypti mosquitoes within urban/exurban areas in Oklahoma is important from an ecological as well as a public health perspective.
Asunto(s)
Aedes , Distribución Animal , Control de Mosquitos/métodos , Feromonas/farmacología , Aedes/fisiología , Animales , Oklahoma , Dinámica PoblacionalRESUMEN
Birds play a central role in the ecology of tick-borne pathogens. They expand tick populations and pathogens across vast distances and serve as reservoirs that maintain and amplify transmission locally. Research into the role of birds for supporting ticks and tick-borne pathogens has largely been descriptive and focused in small areas. To expand inference beyond these studies, we conducted a quantitative review at the scale of North America to identify avian life history correlates of tick infestation and pathogen prevalence, calculate species-level indices of importance for carrying ticks, and identify research gaps limiting understanding of tick-borne pathogen transmission. Across studies, 78 of 162 bird species harbored ticks, yielding an infestation prevalence of 1981 of 38,929 birds (5.1 %). Avian foraging and migratory strategies interacted to influence infestation. Ground-foraging species, especially non-migratory ground foragers, were disproportionately likely to have high prevalence and intensity of tick infestation. Studies largely focused on Borrelia burgdorferi, the agent of Lyme disease, and non-migratory ground foragers were especially likely to carry B. burgdorferi-infected ticks, a finding that highlights the potential importance of resident birds in local pathogen transmission. Based on infestation indices, all "super-carrier" bird species were passerines. Vast interior areas of North America, many bird and tick species, and most tick-borne pathogens, remain understudied, and research is needed to address these gaps. More studies are needed that quantify tick host preferences, host competence, and spatiotemporal variation in pathogen prevalence and vector and host abundance. This information is crucial for predicting pathogen transmission dynamics under future global change.
Asunto(s)
Borrelia burgdorferi , Garrapatas , Animales , Aves , Enfermedad de Lyme , Infestaciones por GarrapatasRESUMEN
Few studies have taken a comprehensive approach of measuring the impact of inter- and intra-specific larval competition on adult mosquito traits. In this study, the impact of competition Aedes aegypti and A. albopictus was quantified over the entire life of a cohort.Competitive treatments affected hatch-to-adult survivorship and development time to adulthood of females for both species, but affected median wing length of females only for A. albopictus. Competitive treatments had no significant effect on the median adult female longevity nor were there any effects on other individual traits related to bloodfeeding and reproductive success.Analysis of life table traits revealed no effect of competitive treatment on net reproductive rate (R0) but there were significant effects on cohort generation time (Tc) and cohort rate of increase (r) for both species.Inter-specific and intra-specific competition among Aedes larvae may produce individual and population-level effects that are manifest in adults; however, benign conditions may enable resulting adults to compensate for some impacts of competition, particularly those affecting blood feeding success, fecundity, and net reproductive rate, R0. The effect of competition, therefore, affects primarily larva - to - adult survivorship and larval development time, which in turn impact the cohort generation time, Tc and ultimately cohort rate of increase, r.The lack of effects of larval rearing environment on adult longevity suggests that effects on vectorial capacity due to longevity may be limited if adults have easy access to sugar and blood meals.
RESUMEN
Some mosquito species utilize the small niches of water that are abundant in farmland habitats. These niches are susceptible to effects from agricultural pesticides, many of which are applied aerially over large tracts of land. One principal form of weed control in agricultural systems involves the development of herbicide-tolerant crops. The impact of sub-agricultural levels of these herbicides on mosquito survival and life-history traits of resulting adults have not been determined. The aim of this study was to test the effect of two commercial herbicides (Beyond and Roundup) on the survivorship, eclosion time, and body mass of Aedes aegypti. First instar A. aegypti larvae were exposed to varying concentrations (270, 550 and 820 µg/m(2) of glyphosate and 0.74, 1.49, 2.24 µL imazamox/m(2)), all treatments being below recommended application rates, of commercial herbicides in a controlled environment and resulting adult mosquitoes were collected and weighed. Exposure to Roundup had a significant negative effect on A. aegypti survivorship at medium and high sub-agricultural application concentrations, and negatively affected adult eclosion time at the highest concentration. However, exposure to low concentrations of Beyond significantly increased A. aegypti survivorship, although adult female mass was decreased at medium sub-agricultural concentrations. These results demonstrate that low concentrations of two different herbicides, which can occur in rural larval habitats as a result of spray drift, can affect the same species of mosquito in both positive and negative ways depending on the herbicide applied. The effects of commercial herbicides on mosquito populations could have an important effect on disease transmission within agricultural settings, where these and other herbicides are extensively applied to reduce weed growth.
Asunto(s)
Aedes/fisiología , Glicina/análogos & derivados , Herbicidas/farmacología , Imidazoles/farmacología , Control de Malezas/métodos , Aedes/efectos de los fármacos , Animales , Productos Agrícolas , Vectores de Enfermedades , Ecosistema , Glicina/farmacología , Rasgos de la Historia de Vida , GlifosatoRESUMEN
Reptiles were collected in nine counties in Oklahoma from September 2002 to May 2004 and examined for Ixodes scapularis (Say) larvae and nymphs to determine seasonal incidence and prevalence of these ticks. In total, 209 reptile specimens consisting of nine species of lizards and seven species of snakes were collected. Plestiodon fasciatus (L.) was the most numerous species collected (55%) followed by Sceloporus undulatus (Latreille) (17%) and Scincella lateralis (Say) (11%). Less than 10 individuals were collected for all remaining reptile species. The infestation prevalence of I. scapularis on all reptile specimens collected was 14% for larvae and 25% for nymphs. Larvae were found on lizards from April until September and peaked in May, while nymphs were found from March until September and peaked in April. I. scapularis larvae (84%) and nymphs (73%) preferentially attached to the axillae/front leg of P. fasciatus. Two chigger species, Eutrombicula splendens (Ewing) and Eutrombicula cinnabaris (Ewing), were found on 2% of the reptiles collected. No ectoparasites, including ticks, were obtained from the seven species of snakes collected.
Asunto(s)
Ixodes/fisiología , Lagartos/parasitología , Serpientes/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Incidencia , Ixodes/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/fisiología , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Oklahoma/epidemiología , Prevalencia , Estaciones del Año , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitologíaRESUMEN
Geographic distribution records for the lone star tick [Amblyomma americanum (L.)] in the peer-reviewed literature are incomplete for Oklahoma, preventing accurate disease risk assessments. To address this issue and document the presence of A. americanum in available habitats throughout the state, county-scale tick records published in U.S. Department of Agriculture-Cooperative Economic Insect Reports and specimens maintained at the K.C. Emerson Entomology Museum, Oklahoma State University, were reviewed. In addition, dry ice traps and tick drags were used to collect adult and nymphal A. americanum from throughout the state. Review of published USDA reports and the local museum collection documented A. americanum in 49 total counties (35 and 35, respectively). Active surveillance efforts confirmed the presence of this tick in 50 counties from which this species had not been previously reported to be established, documenting A. americanum is established in 68 of the 77 (88.3%) counties in Oklahoma. Taken together, these data verify that A. americanum ticks are much more widespread in Oklahoma than reflected in the literature, a phenomenon likely repeated throughout the geographic range of this tick in the eastern half of North America.
Asunto(s)
Ixodidae , Animales , Demografía , OklahomaRESUMEN
A series of statewide surveys were conducted in Oklahoma in the summers between 1991 and 2004 to identify the distribution of Aedes albopictus. Adult mosquitoes were identified in 63 counties, bringing the currently known distribution of Ae. albopictus in the state to 69 of 77 counties. The widespread presence of Ae. albopictus in Oklahoma has important current and future public and veterinary health implications for surveillance and control efforts.
Asunto(s)
Aedes/fisiología , Aedes/virología , Distribución Animal , Infecciones por Arbovirus/transmisión , Infecciones por Arbovirus/virología , Arbovirus/fisiología , Insectos Vectores , Animales , Insectos Vectores/fisiología , Insectos Vectores/virología , OklahomaRESUMEN
The mosquito fauna of Oklahoma has not been evaluated since 1965 and no report has been published concerning species associated with urban areas in the state. Mosquito collections were conducted as part of the West Nile virus (WNV) surveillance program between April and November from 2003 to 2006, using standard collection methods. A total of 74,756 adults were collected in 26 urban centers in 16 counties of Oklahoma. Altogether, 40 species were recorded during this study period, bringing the total mosquito species recorded in Oklahoma to 62 species in 9 different genera and 18 subgenera. An updated checklist of Oklahoma mosquito fauna is included with a comparison to historical records. New state records include 3 species: Aedes muelleri, Anopheles perplexens, and Culex coronator. In addition to updating the checklist, 12 species of mosquitoes were tested for WNV. Pools of Culex pipiens complex represented the highest proportion testing positive for WNV (134/766, 17.5%), followed by Cx. tarsalis (13/192, 6.8%) and Aedes albopictus (5/215, 2.3%). West Nile virus-positive mosquitoes were detected earliest in June 2005 and latest in November 2004. Infected Cx. pipiens complex testing positive for WNV were more prevalent in the eastern and central areas of Oklahoma, whereas positive Cx. tarsalis were found mainly in the western areas of the state. This distinct geographical difference needs to be monitored and followed up to ensure optimal mosquito control efforts in Oklahoma communities with mosquito control capabilities.
Asunto(s)
Distribución Animal , Culicidae/clasificación , Culicidae/virología , Insectos Vectores/clasificación , Insectos Vectores/virología , Virus del Nilo Occidental/aislamiento & purificación , Animales , Femenino , OklahomaRESUMEN
Urbanization alters abiotic conditions, vegetation, and wildlife populations in ways that affect tick abundance and tick-borne disease prevalence. Likely due to such changes, tick abundance has increased in many US urban areas. Despite growing public health importance of tick-borne diseases, little is known about how ticks are influenced by urbanization in North America, especially in the central United States where several pathogens occur at or near their highest incidences. To identify factors influencing tick abundance across a gradient of urbanization intensity, we used CO2 traps and flagging to sample ticks at 16 parks across Oklahoma City, Oklahoma, USA over 2 yr, conducted vegetation surveys, and used trail cameras to estimate a deer abundance index. Our results indicate there is a risk of encountering ticks across the entire urbanization gradient from exurban areas to the urban core, although some species (Dermacentor variabilis (Say)) appear less-common in heavily-urbanized areas. Vegetation variables were also associated with tick abundance. For example, Amblyomma maculatum Koch decreased with increasing woody plant and leaf litter cover, and there was a weak positive relationship between D. variabilis abundance and cover of understory eastern redcedar (Juniperus virginiana L.), indicating this native encroaching tree may increase tick populations in urban areas of the Great Plains. The deer abundance index was positively correlated with A. maculatum and D. variabilis abundance but unrelated to A. americanum (L.) abundance. Public health officials and land managers can use such information about parks/greenspaces and their surroundings to focus public education and land management efforts designed to reduce tick-borne disease prevalence.
Asunto(s)
Ciervos , Ixodidae , Enfermedades por Picaduras de Garrapatas , Garrapatas , Animales , Estados Unidos , Remodelación Urbana , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/veterinariaRESUMEN
Some of the most prevalent arthropod-borne pathogens impacting humans in the United States are transmitted by Ixodes ticks. However, little is known regarding the Rickettsia species that inhabit Ixodes scapularis in the United States. The aim of this study was to screen adult I. scapularis collected in central Oklahoma over an 8-yr period for the presence of tick-borne rickettsial pathogens or potential pathogens. During 2014-2021, 112 adult specimens of I. scapularis were collected from central Oklahoma. Amplicons for Rickettsia spp. were amplified from 53 (47.3%) of the samples. Of the positive ticks, 42 (79.2%) amplicon-positive Rickettsia samples were 100% identical to Rickettsia buchneri, 10 (18.9%) were 100% identical to R. tillamookensis strain Tillamook 23, and 1 (1.9%) specimen showed high identity for Rickettsia amblyommatis. This study highlights the importance of considering Rickettsia-specific assays when assessing Ixodes species ticks for potential pathogens.
Asunto(s)
Ixodes , Ixodidae , Rickettsia , Rickettsiaceae , Humanos , Animales , Ixodes/microbiología , Ixodidae/microbiología , Rickettsiales , OklahomaRESUMEN
Predatory mites display diverse ecological mechanisms to suppress pest population density below certain thresholds known to cause economic loss. The current study explored the numerical responses of the predatory mites, Cheyletus eruditus (Schrank) (Trombidiformes: Cheyletidae) and Cheyletus malaccensis Oudemans, to Liposcelis decolor (Pearman) (Psocodea: Liposcelididae). The numerical responses of these 2 cheyletid mites to nymphs, adult males, and adult females of L. decolor were determined under laboratory conditions at 24 ± 1 °C, 85 ± 5 RH, and 0:24 (L:D) photoperiod. Oviposition rate, oviposition efficiency, and efficiency of conversion of ingested (ECI) food resources were the key numerical response parameters assessed. The present study revealed a general trend of a strong negative and positive correlation between oviposition rates and increase in prey densities (number of prey per 16.98 cm2) for C. eruditus and C. malaccensis, respectively. The oviposition efficiency was mostly similar for both predatory mites and was inversely related to prey density. Generally, ECI (%) decreased considerably with increasing prey density across different prey types for both predators, however, C. malaccensis was more efficient than C. eruditus in utilizing prey biomass. Given the relatively weak numerical responses, we recommended further assessment of these predatory mites before recommending their use for managing stored-product insect pests in the United States.
Asunto(s)
Ácaros , Femenino , Masculino , Animales , Ácaros/fisiología , Insectos , Oviposición , Conducta Predatoria , Densidad de PoblaciónRESUMEN
Predator-prey interactions are linked through trophic relationships, and individual population dynamics are a function of multiple interactions among many ecological factors. The present study considered the efficacy of the predatory mites Cheyletus eruditus (Schrank) (Trombidiformes: Cheyletidae) and Cheyletus malaccensis Oudemans to manage Liposcelis decolor (Pearman) (Psocodea: Liposcelididae). Prey population suppression and progeny replacement efficiency of the predators were assessed under different predator-prey ratios (0:20, 1:20, 2:20, 4:20, and 10:20), temperatures (20, 24, 28, and 32 °C), and relative humidities (RH) (63, 75, and 85%) over 40 days under laboratory conditions of 0:24 (L:D) photoperiod. Suppression of L. decolor population when C. eruditus-related predator-to-prey ratios of 1:20, 2:20, 4:20, and 10:20 were used was ~61.7, 79.7, 85.1, and 87.5%, respectively, relative to the Control ratio (0:20). In the case of C. malaccensis, suppression of 70, 82.1, 92.9, and 96.5%, respectively, was achieved. Although the low 63% RH limited efficacy of these cheyletid mites, both predatory mites caused pest population suppression of ~67.1-97.2% and increased their progeny by ~96.7-844.4% fold for the predator-prey ratios of 1:20, 2:20, 4:20, and 10:20, temperatures of 20, 24, 28, and 32 °C, and RH levels of 63, 75, and 85%. The levels of psocid population suppression achieved indicate the potential of both predatory mites for psocid management.
RESUMEN
Rickettsia sp. and Bartonella sp. were detected in ectoparasites of free-roaming domestic cats (Felis catus) from a trap-neuter-release program in central Oklahoma during January and February 2020. We used polymerase chain reaction and sequencing to identify fleas containing DNA of five different pathogens: Rickettsia felis (84%), 'Candidatus R. andeanae' (8%), Bartonella henselae (32%), Bartonella clarridgeiae (36%), and Bartonella sp. (8%). Co-infections with R. felis with three Bartonella species were identified. One tick was positive for R. felis, one flea was positive for 'Candidatus R. andeanae' and one ear mite was positive for a Bartonella species. These results highlight the need for more focus on free-roaming domestic cats and their ectoparasites in the Great Plains region.
Asunto(s)
Enfermedades de los Gatos , Felis , Infestaciones por Pulgas , Rickettsia felis , Siphonaptera , Animales , Enfermedades de los Gatos/epidemiología , Gatos , Infestaciones por Pulgas/epidemiología , Infestaciones por Pulgas/parasitología , Infestaciones por Pulgas/veterinaria , Prevalencia , Rickettsia felis/genética , Siphonaptera/microbiología , Estados UnidosRESUMEN
Urbanization alters components of natural ecosystems which can affect tick abundance and tick-borne disease prevalence. Likely due to these changes, tick-borne pathogen prevalence has increased in many U.S. urban areas. Despite the growing public health importance of tick-borne diseases, little is known about how they are influenced by urbanization in North America, especially in the central U.S. where several pathogens occur at or near their highest levels of incidence nationally. To determine whether urban development influences tick infection with bacteria and protozoa, we collected ticks at 16 parks across a gradient of urbanization intensity in Oklahoma City, Oklahoma, USA and tested them using a variety of PCR assays. Adult ticks tested positive for Rickettsia parkeri, R. amblyommatis, R. rhiphicephali, 'Candidatus R. andeanae', Ehrlichia chaffeensis, E. ewingii, Panola Mountain Ehrlichia, 'Borrelia lonestari', Theileria cervi, Babesia spp. Coco, and Cytauxzoon felis. These results indicate the presence of a high diversity of tick-borne bacteria and protozoa across an expanding urban area in the U.S. Great Plains. Although there appeared to be some risk of encountering tick-borne microorganisms across the entire urbanization gradient, E. chaffeensis, E. ewingii, and T. cervi-infected ticks and microbe diversity decreased with increasing urbanization intensity. We identified a low rate of coinfection between different microorganisms, with coinfected ticks mainly collected from sites in the least-urbanized areas. This study suggests the need for awareness of tick-borne disease risk throughout urban areas in the central U.S., and highlights a need for studies of tick host habitat use and movement in cities.
Asunto(s)
Coinfección , Ehrlichia chaffeensis , Rickettsia , Enfermedades por Picaduras de Garrapatas , Garrapatas , Animales , Ecosistema , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , UrbanizaciónRESUMEN
Woody plant encroachment into grasslands is occurring worldwide, affecting ecosystems in ways that likely influence mosquito-borne disease transmission. In the U.S. Great Plains, encroachment by eastern redcedar (Juniperus virginiana) (ERC) may be expanding conducive habitat for mosquitoes and their hosts, but few studies have evaluated associations between ERC encroachment and West Nile virus (WNV). To test the hypotheses that mosquito abundance and WNV-infected mosquitoes increase with increasing ERC cover, we collected mosquitoes in 32 sites in Oklahoma reflecting various ERC encroachment stages. We found support for our first hypothesis, as mean abundance of Aedes albopictus increased significantly with ERC cover. However, Psorophora columbiae and Anopheles quadrimaculatus abundance decreased with increasing ERC. There was no significant association with ERC for other mosquito species. We could not test our second hypothesis due to low WNV prevalence, but the only detected WNV-infected pool of mosquitoes (Cx. tarsalis) was collected in ERC. Our results suggest ERC encroachment increases abundance of at least one medically important mosquito species, but further research is needed to clarify how encroachment affects ecology of the entire WNV disease system through changes to vector and host communities, vector-host interactions, and thus disease transmission and prevalence. Understanding relationships between woody plant encroachment and the nidus of infection for mosquito-borne diseases will be crucial for targeting public health efforts, including land management activities that limit and/or eradicate woody plant encroachment, particularly in areas with high levels of disease risk.
Asunto(s)
Aedes , Culex , Bosques , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Ecosistema , Mosquitos Vectores , OklahomaRESUMEN
Currently utilized molecular detection methods are based mainly on nucleic acid extraction, amplification, and detection procedures that may require costly equipment, numerous reagents, and highly trained personnel. These requirements make diagnostic tests expensive, time-consuming, and not suitable for point-of-care applications. There is an increasing demand for simple, low-cost portable technologies. To overcome these challenges, a paper-based elution independent collection device (EICD) was designed to collect microorganisms and recover nucleic acids for molecular biology applications with minimal steps. In this study, we demonstrate a simpler Anaplasma marginale detection that uses an EICD for nucleic acid collection combined with recombinase polymerase amplification (RPA), and a lateral flow dipstick for detection of the specified target. A pre-lysis blood treatment was optimized that uses Triton X-100 lysis buffer and bovine serum album in wash buffer. Blood samples were incubated for 5 min at room temperature and run through the EICD. Four 1-mm diameter discs excised from EICD were used as template in basic RPA and lateral flow (nfo) (endonuclease IV) RPA assays. Each disc of soluble central membrane (SCM) carried circa 0.249 pg/µl of Anaplasma DNA. The percentage of nucleic acid recoverable from the SCM ranged between 60% - 70%. Blood samples infected with A. marginale were treated with Triton X-100 pre-lysis protocol. All samples tested positive by PCR and RPA methods. EICD-driven collection of blood samples is a practical method successfully adapted to detect Anaplasma spp. or blood-borne pathogen DNA and has potential for point-of-care detection in resource-limited settings.
Asunto(s)
Anaplasma marginale , Anaplasma , Anaplasma marginale/genética , ADN , Técnicas de Amplificación de Ácido Nucleico , Recombinasas , Sensibilidad y EspecificidadRESUMEN
In the south-central United States, several tick-borne diseases (TbDs) occur at or near their highest levels of incidence of anywhere in the U.S. The diversity of Rickettsia species found in Amblyomma americanum continues to be under-characterized in this region and throughout the U.S. and Canada where this tick species is expanding. One reason for this lack of knowledge about Rickettsia diversity is the high prevalence of the endosymbiont Rickettsia amblyommatis that obscures detection of other bacteria in this genus. Focusing on unknown rickettsial agents, we used a recently described R. amblyommatis exclusion assay to screen 1909 A. americanum collected in Oklahoma City, Oklahoma, which resulted in eight ticks that had unique rickettsial sequences. Through the process of characterizing primary and secondary rickettsiae, we identified ticks primarily infected with Rickettsia rhipicephali and a Rickettsia species (2019-CO-FNY) previously linked with a canine rickettsiosis case in Tulsa, Oklahoma. We also identified a Rickettsia agent that was 97% identical with an endosymbiont of Amblyomma tonelliae and which aligned with archaic rickettsial species. Through this study, we further demonstrate the usefulness of this exclusion assay for rapid screening in large cohort A. americanum studies to identify a small number of ticks that contain poorly described and previously undocumented rickettsiae.
Asunto(s)
Ixodidae , Rickettsia , Garrapatas , Amblyomma , Animales , Canadá , Perros , Humanos , Ixodidae/microbiología , Oklahoma/epidemiologíaRESUMEN
Tick-borne diseases are an increasing concern for people and companion animals in the United States, but there is a need for continued vigilance regarding livestock in pasture systems. The south-central United States has some of the highest incidences of tick-borne diseases, and there is a need to re-examine the ecology of tick vectors in relation to pasture systems and livestock. The objective of this study was to establish a baseline of seasonal activity for tick species in diverse regional Oklahoma pastures and screen for important pathogens in Dermacentor variabilis (Say) and Amblyomma maculatum Koch group that may impact livestock and human health. Between 2015 and 2017, transects in five pastures across Oklahoma were visited each month. DNA extracted from adult D. variabilis and A. maculatum group was tested for the presence of bacterial pathogens. We found that tick communities in pastures across Oklahoma differ by season, abundance, and bacterial presence and prevalence. The peak abundance of Amblyomma americanum (L.) adults and nymphs occurred a month earlier over the 2 yr of the study compared with historical studies in the same regions. Additionally, we observed notable differences in peak activity between A. americanum adults and nymphs collected in pastures in central Oklahoma (April) versus pastures in northern part of the state (May). We detected Rickettsia parkeri, R. bellii, and Anaplasma sp. DNA in D. variabilis from pastures across the state. These results potentially have important ramifications for human and livestock risk of encountering infected ticks in pastures across the southern Great Plains.
Asunto(s)
Dermacentor , Ixodidae , Rickettsia , Enfermedades por Picaduras de Garrapatas , Amblyomma , Animales , Dermacentor/microbiología , Humanos , Ixodidae/microbiología , Ninfa , Oklahoma/epidemiología , Prevalencia , Rickettsia/genética , Enfermedades por Picaduras de Garrapatas/epidemiologíaRESUMEN
CONTEXT: A key element of the doctor-patient relationship is to understand the patient's and doctor's perceptions of quality care. OBJECTIVES: To assess the perceptions of good and bad doctors among first-year medical students and local community members in a semi-urban, African settings. METHODS: Using open-ended and closed dichotomous questions, 115 first-year medical students in Beira, Mozambique were surveyed regarding their perceptions of a 'good' and 'bad' doctor. Students then surveyed 611 community members in a predominately poor, semi-urban neighbourhood. RESULTS: Answers to open-ended questions provided by both groups produced the same four most important positive characteristics, with good diagnostic and therapeutic skills and dedication ranked highest. Closed-ended questions revealed that local community members felt that being concerned/considerate and diagnosing well were equally important (19.5% and 17.5%, respectively) compared to students (17.5% and 41.2%, respectively). The most important negative characteristics to the open-ended question for both groups were discrimination and contemptuous behaviour: 29.3% for community members and 27.4% for medical students. The biggest difference between groups was poor attending skills: 17.3% by community members and 3.9% by medical students. CONCLUSION: This study highlights differences and similarities between the perceptions of medical students and community members concerning a 'good' and a 'bad' doctor. Our data suggest that perceptions are guided by the experiences and values of those interviewed. Results indicate that medical education in developing countries should focus on patient-centered care, including communication skills and attitudes, besides training knowledgeable doctors.