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1.
J Med Entomol ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33825903

RESUMO

Lyme disease is the most common tick-borne disease in North America. Though human infection is mostly transmitted in a limited geography, the range has expanded in recent years. One notable area of recent expansion is in the mountainous region of southwestern Virginia. The ecological factors that facilitate or constrain the range of human Lyme disease in this region remain uncertain. To evaluate this further, we obtained ecological data, including remotely sensed data on forest structure and vegetation, weather data, and elevation. These data were aggregated within the census block groups of a 9,153 km2 area around the cities of Blacksburg and Roanoke, VA, an area with heterogeneous Lyme disease transmission. In this geographic area, 755 individuals were reported to have Lyme disease in the 10 yr from 2006 to 2015, and these cases were aggregated by block group. A zero-inflated negative binomial model was used to evaluate which environmental variables influenced the abundance of Lyme disease cases. Higher elevation and higher vegetation density had the greatest effect size on the abundance of Lyme disease. Measures of forest edge, forest integrity, temperature, and humidity were not associated with Lyme disease cases. Future southward expansion of Lyme disease into the southeastern states may be most likely in ecologically similar mountainous areas.

2.
Ticks Tick Borne Dis ; 12(3): 101679, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33578256

RESUMO

Ticks and tick-borne rickettsial diseases have been gaining greater attention in China over the past decade. However, most published studies to date have occurred in Northern China, with limited investigations occurring in China's southern provinces. As part of larger surveillance efforts, a cross-sectional survey was conducted in six sites at Guangdong, Guangxi and Yunnan investigating rickettsial infection in ticks. A total of 581 ticks were collected from hosts and screened via PCR, targeting rrs, gltA, ompB, sca4, and ompA gene fragments. Two of 12 Haemaphysalis formosensis ticks were infected with novel Rickettsia strain GD01, which was closest phylogenetically (97.3-98.9 % identity) to Rickettsia tamurae strain AT-1, but not within the same clade. Another detected strain (GD02) shared similar identity, 99-100 % across four gene targets, to recently detected Candidatus Rickettsia longicornii isolate ROK-HL727, with an overall prevalence of 12.5 % (71/569). The presence of such pathogens calls for increased public health attention and active surveillance in patients reporting recent tick bites.

3.
Pathogens ; 9(11)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202715

RESUMO

Tick-borne infections are a significant threat to public health, particularly in regions where individuals frequently enter tick habitats. Roughly 26% of the population in Mongolia practice nomadic pastoralism and are considered at high risk of exposure to ticks and the diseases they carry. This study tested ticks from Mongolia's southern border for Rickettsia spp. to better understand the epidemiology of tick-borne diseases in the region. Dermacentor nuttalli and Hyalomma asiaticum ticks (n = 4022) were pooled and tested for Rickettsia spp. by real-time PCR. Melt-curve analyses and Sanger sequencing were used to identify Rickettsia species. Approximately 64% of the 786 tick pools tested positive for Rickettsia bacteria. Melt curve analyses identified four different Rickettsia species circulating in these tick pools. Amplicon sequencing of the ompA gene identified Rickettsia spp. that closely resembled R. raoultii and R. sibirica. Dermacentor nuttalli ticks from Govi-Altai had the highest maximum likelihood estimation infection rate 48.4% (95% CI: 41.7-56.5%), while Hyalommaasiaticum collected in Omnogovi had a rate of 7.6% (95% CI: 6.2-9.2%). The high detection of Rickettsia suggests a substantial risk of infection in southern Mongolia. Further studies are necessary to investigate the clinical burden of tick-borne diseases in Mongolia.

4.
PLoS One ; 15(10): e0240786, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33064753

RESUMO

BACKGROUND: The Centers for Disease Control and Prevention (CDC) publishes COVID-19 non-pharmaceutical intervention (NPI) guidance for specific institutional audiences to limit community spread. Audiences include: business, clinical, public health, education, community, and state/local government. The swift, severe, and global nature of COVID-19 offers an opportunity to systematically obtain a national view of how larger institutions of higher education adopted NPI guidance at the onset of the pandemic. METHOD: An original database of COVID-19-related university NPI policy changes was compiled. Survey team members manually combed university websites and official statements capturing implementation decisions and dates for five NPI variables from 575 U.S. universities, across 50 states and the District of Columbia, during March of 2020. The universities included in this study were selected from the Department of Education Integrated Postsecondary Education Data System (IPEDS), which provides a set of university explanatory variables. Using IPEDS as the basis for the organizational data allows consistent mapping to event-time and institutional characteristic variables including public health announcements, geospatial, census, and political affiliation. RESULTS: The dataset enables event-time analysis and offers a variety of variables to support institutional level study and identification of underlying biases like educational attainment. A descriptive analysis of the dataset reveals that there was substantial heterogeneity in the decisions that were made and the timing of these decisions as they temporally related to key state, national, and global emergency announcements. The WHO pandemic declaration coincided with the largest number of university decisions to implement NPIs. CONCLUSION: This study provides descriptive observations and produced an original dataset that will be useful for future research focused on drivers and trends of COVID-19 NPIs for U.S. Universities. This preliminary analysis suggests COVID-19 university decisions appeared to be made largely at the university level, leading to major variations in the nature and timing of the responses both between and within states, which requires further study.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Controle de Infecções/métodos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Universidades , Centers for Disease Control and Prevention, U.S. , Infecções por Coronavirus/virologia , Tomada de Decisões , Educação a Distância/métodos , Humanos , Pneumonia Viral/virologia , Saúde Pública , Estudantes , Inquéritos e Questionários , Viagem , Estados Unidos/epidemiologia
7.
PLoS Med ; 17(5): e1003084, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32407380

RESUMO

BACKGROUND: The radical cure of Plasmodium vivax and P. ovale requires treatment with primaquine or tafenoquine to clear dormant liver stages. Either drug can induce haemolysis in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, necessitating screening. The reference diagnostic method for G6PD activity is ultraviolet (UV) spectrophotometry; however, a universal G6PD activity threshold above which these drugs can be safely administered is not yet defined. Our study aimed to quantify assay-based variation in G6PD spectrophotometry and to explore the diagnostic implications of applying a universal threshold. METHODS AND FINDINGS: Individual-level data were pooled from studies that used G6PD spectrophotometry. Studies were identified via PubMed search (25 April 2018) and unpublished contributions from contacted authors (PROSPERO: CRD42019121414). Studies were excluded if they assessed only individuals with known haematological conditions, were family studies, or had insufficient details. Studies of malaria patients were included but analysed separately. Included studies were assessed for risk of bias using an adapted form of the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Repeatability and intra- and interlaboratory variability in G6PD activity measurements were compared between studies and pooled across the dataset. A universal threshold for G6PD deficiency was derived, and its diagnostic performance was compared to site-specific thresholds. Study participants (n = 15,811) were aged between 0 and 86 years, and 44.4% (7,083) were women. Median (range) activity of G6PD normal (G6PDn) control samples was 10.0 U/g Hb (6.3-14.0) for the Trinity assay and 8.3 U/g Hb (6.8-15.6) for the Randox assay. G6PD activity distributions varied significantly between studies. For the 13 studies that used the Trinity assay, the adjusted male median (AMM; a standardised metric of 100% G6PD activity) varied from 5.7 to 12.6 U/g Hb (p < 0.001). Assay precision varied between laboratories, as assessed by variance in control measurements (from 0.1 to 1.5 U/g Hb; p < 0.001) and study-wise mean coefficient of variation (CV) of replicate measures (from 1.6% to 14.9%; p < 0.001). A universal threshold of 100% G6PD activity was defined as 9.4 U/g Hb, yielding diagnostic thresholds of 6.6 U/g Hb (70% activity) and 2.8 U/g Hb (30% activity). These thresholds diagnosed individuals with less than 30% G6PD activity with study-wise sensitivity from 89% (95% CI: 81%-94%) to 100% (95% CI: 96%-100%) and specificity from 96% (95% CI: 89%-99%) to 100% (100%-100%). However, when considering intermediate deficiency (<70% G6PD activity), sensitivity fell to a minimum of 64% (95% CI: 52%-75%) and specificity to 35% (95% CI: 24%-46%). Our ability to identify underlying factors associated with study-level heterogeneity was limited by the lack of availability of covariate data and diverse study contexts and methodologies. CONCLUSIONS: Our findings indicate that there is substantial variation in G6PD measurements by spectrophotometry between sites. This is likely due to variability in laboratory methods, with possible contribution of unmeasured population factors. While an assay-specific, universal quantitative threshold offers robust diagnosis at the 30% level, inter-study variability impedes performance of universal thresholds at the 70% level. Caution is advised in comparing findings based on absolute G6PD activity measurements across studies. Novel handheld quantitative G6PD diagnostics may allow greater standardisation in the future.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Espectrofotometria , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimaláricos/uso terapêutico , Criança , Pré-Escolar , Feminino , Deficiência de Glucosefosfato Desidrogenase/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Malária/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-32053906

RESUMO

Land use boundaries represent human-physical interfaces where risk of vector-borne disease transmission is elevated. Land development practices, coupled with rural and urban land fragmentation, increases the likelihood that immunologically naïve humans will encounter infectious vectors at land use interfaces. This research consolidated land use classes from the GLC-SHARE dataset; calculated landscape metrics in linear (edge) density, proportion abundance, and patch density; and derived the incidence rate ratios of the Zika virus occurrence in Colombia, South America during 2016. Negative binomial regression was used to evaluate vector-borne disease occurrence counts in relation to Population Density, Average Elevation, Per Capita Gross Domestic Product, and each of three landscape metrics. Each kilometer of border length per square kilometer of area increase in the linear density of the Cropland and Grassland classes is associated with an increase in Zika virus risk. These spatial associations inform a risk reduction approach to rural and urban morphology and land development that emphasizes simple and compact land use geometry that decreases habitat availability for mosquito vectors of Zika virus.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Colômbia/epidemiologia , Meio Ambiente , Humanos , Mosquitos Vetores , População Rural , América do Sul , População Urbana , Infecção por Zika virus/epidemiologia
9.
Malar J ; 19(1): 35, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964374

RESUMO

BACKGROUND: Quality control of indoor residual spraying (IRS) is necessary to ensure that spray operators (SOs) deposit the correct concentration of insecticide on sprayed structures, while also confirming that spray records are not being falsified. METHODS: Using high-performance liquid chromatography (HPLC), this study conducted quality control of the organophosphate insecticide pirimiphos-methyl (Actellic 300CS), during the 2018 IRS round on Bioko Island, Equatorial Guinea. Approximately 60 SOs sprayed a total of 67,721 structures in 16,653 houses during the round. Houses that were reportedly sprayed were randomly selected for quality control testing. The SOs were monitored twice in 2018, an initial screening in March followed by sharing of results with the IRS management team and identification of SOs to be re-trained, and a second screening in June to monitor the effectiveness of training. Insecticide samples were adhesive-lifted from wooden and cement structures and analysed using HPLC. RESULTS: The study suggests that with adequate quality control measures and refresher training, suboptimal spraying was curtailed, with a significant increased concentration delivered to the bedroom (difference = 0.36, P < 0.001) and wooden surfaces (difference 0.41, P = 0.001). Additionally, an increase in effective coverage by SOs was observed, improving from 80.7% in March to 94.7% in June after re-training (McNemar's test; P = 0.03). CONCLUSIONS: The ability to randomly select, locate, and test houses reportedly sprayed within a week via HPLC has led to improvements in the performance of SOs on Bioko Island, enabling the project to better evaluate its own performance.


Assuntos
Inseticidas/administração & dosagem , Malária/prevenção & controle , Controle de Mosquitos/normas , Compostos Organotiofosforados/administração & dosagem , Aerossóis , Animais , Cromatografia Líquida de Alta Pressão/economia , Guiné Equatorial , Habitação , Humanos , Ilhas , Controle de Mosquitos/métodos , Organofosfatos/análise , Controle de Qualidade , Estações do Ano , Fatores de Tempo
10.
PLoS One ; 15(1): e0226798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978068

RESUMO

Peromyscus leucopus (the white-footed mouse) is a known reservoir of the Lyme disease spirochete Borrelia burgdorferi. Sampling of white-footed mice allows for year-round B. burgdorferi surveillance as well as opportunities to establish the diversity of the different variants in a geographic region. This study explores the prevalence of B. burgdorferi infections in the tissues of white-footed mice, investigates the correlations between B. burgdorferi infected tissues, and determines the optimum field methods for surveillance of B. burgdorferi in P. leucopus. A total of 90 mice and 573 tissues (spleen, liver, ear, tongue, tail, heart, and kidney) were screened via nested PCR for B. burgdorferi infections. A large number of infections were found in the 90 mice as well as multiple infections within individual mice. Infections in a single mouse tissue (spleen, liver, ear, tongue and tail) were predictive of concurrent infection in other tissues of the same mouse at a statistically significant level. Ear tissue accounted for 68.4% of detected infections, which increased to 78.9% of the infected mice with the inclusion of tail samples. The use of ear punch or tail snip samples (used individually or in tandem) have multiple advantages over current Lyme disease ecological studies and surveillance methodologies, including lower associated costs, minimization of delays, year-round B. burgdorferi testing opportunities, as well as longitudinal monitoring of B. burgdorferi in defined geographic regions. In the absence of an effective vaccine, personal prevention measures are currently the most effective way to reduce Lyme disease transmission to humans. Thus, the identification and monitoring of environmental reservoirs to inform at-risk populations remains a priority. The sampling methods proposed in this study provide a reasonable estimate of B. burgdorferi in white-footed mice in a timely and cost-effective manner.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Doença de Lyme/veterinária , Peromyscus/microbiologia , Doenças dos Roedores/microbiologia , Manejo de Espécimes/normas , Animais , Reservatórios de Doenças , Feminino , Doença de Lyme/microbiologia , Masculino , Camundongos , Doenças dos Roedores/epidemiologia , Manejo de Espécimes/métodos
11.
Ticks Tick Borne Dis ; 11(1): 101316, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677968

RESUMO

Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause human granulocytic anaplasmosis, human monocytic ehrlichiosis, and are severe threats to livestock economies like Mongolia. In this study, ticks were collected, identified, and pooled (n = 299) from three distinct environments across central Mongolia. Each pool was initially tested for Anaplasma/Ehrlichia using a 16S rRNA PCR assay that detects both genera, and specific PCR testing was done to identify those positive samples. Maximum likelihood estimation (MLE) of infection rates of ticks collected from the environment in Selenge aimag (province) found infection rates of Ixodes persulcatus ticks to be 2.0% (95% CI: 0.7, 4.3%) for A. phagocytophilum and 0.8% (95% CI: 0.1, 2.5%) for both nonspecific Ehrlichia and Anaplasma. Ehrlichia muris was only detected in I. persulcatus ticks collected from the Selenge aimag, where the MLE was 1.2% (95% CI: 0.1, 2.5%). The calculated MLE infection rate of Anaplasma spp. in questing Dermacentor nuttalli ticks ranged from 1.9% (95% CI: 1.1, 9.1%) in the Tov aimag to 2.3% (95% CI: 1.3, 10.8%) in the Selenge aimag. However, when examining MLE in ticks removed from livestock, estimates increase substantially, ranging from 7.8% (95% CI: 4.2, 13.3%) in Dornogovi to 22.5% (95% CI: 14.3, 34.3%) in Selenge, suggesting that livestock play a key role in disease maintenance. Considering the collective economic losses that can result from these pathogens and the potential for illness in nomadic herdsmen, these results highlight the need for enhanced TBD surveillance and prevention measures within Mongolia.

12.
PLoS Med ; 16(12): e1002992, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31834890

RESUMO

BACKGROUND: To reduce the risk of drug-induced haemolysis, all patients should be tested for glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd) prior to prescribing primaquine (PQ)-based radical cure for the treatment of vivax malaria. This systematic review and individual patient meta-analysis assessed the utility of a qualitative lateral flow assay from Access Bio/CareStart (Somerset, NJ) (CareStart Screening test for G6PD deficiency) for the diagnosis of G6PDd compared to the gold standard spectrophotometry (International Prospective Register of Systematic Reviews [PROSPERO]: CRD42019110994). METHODS AND FINDINGS: Articles published on PubMed between 1 January 2011 and 27 September 2019 were screened. Articles reporting performance of the standard CSG from venous or capillary blood samples collected prospectively and considering spectrophotometry as gold standard (using kits from Trinity Biotech PLC, Wicklow, Ireland) were included. Authors of articles fulfilling the inclusion criteria were contacted to contribute anonymized individual data. Minimal data requested were sex of the participant, CSG result, spectrophotometry result in U/gHb, and haemoglobin (Hb) reading. The adjusted male median (AMM) was calculated per site and defined as 100% G6PD activity. G6PDd was defined as an enzyme activity of less than 30%. Pooled estimates for sensitivity and specificity, unconditional negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated comparing CSG results to spectrophotometry using a random-effects bivariate model. Of 11 eligible published articles, individual data were available from 8 studies, 6 from Southeast Asia, 1 from Africa, and 1 from the Americas. A total of 5,815 individual participant data (IPD) were available, of which 5,777 results (99.3%) were considered for analysis, including data from 3,095 (53.6%) females. Overall, the CSG had a pooled sensitivity of 0.96 (95% CI 0.90-0.99) and a specificity of 0.95 (95% CI 0.92-0.96). When the prevalence of G6PDd was varied from 5% to 30%, the unconditional NPV was 0.99 (95% CI 0.94-1.00), with an LR+ and an LR- of 18.23 (95% CI 13.04-25.48) and 0.05 (95% CI 0.02-0.12), respectively. Performance was significantly better in males compared to females (p = 0.027) but did not differ significantly between samples collected from capillary or venous blood (p = 0.547). Limitations of the study include the lack of wide geographical representation of the included data and that the CSG results were generated under research conditions, and therefore may not reflect performance in routine settings. CONCLUSIONS: The CSG performed well at the 30% threshold. Its high NPV suggests that the test is suitable to guide PQ treatment, and the high LR+ and low LR- render the test suitable to confirm and exclude G6PDd. Further operational studies are needed to confirm the utility of the test in remote endemic settings.


Assuntos
Testes Diagnósticos de Rotina , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Glucosefosfato Desidrogenase/genética , Primaquina/uso terapêutico , Testes Diagnósticos de Rotina/métodos , Doenças Endêmicas , Feminino , Deficiência de Glucosefosfato Desidrogenase/tratamento farmacológico , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Malária Vivax/epidemiologia , Masculino , Sistemas Automatizados de Assistência Junto ao Leito , Primaquina/efeitos adversos , Sensibilidade e Especificidade
13.
Emerg Infect Dis ; 25(11): 2147-2149, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31625860

RESUMO

Human yaws has historically been endemic to Kenya, but current epidemiologic data are lacking. We report seroprevalence for Treponema pallidum antibodies in olive baboons (Papio anubis) and vervet monkeys (Chlorocebus pygerythrus) in Laikipia County, Kenya. Our results suggest endemicity of the yaws bacterium in monkeys, posing a possible zoonotic threat to humans.


Assuntos
Anticorpos Antibacterianos/imunologia , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/microbiologia , Estudos Soroepidemiológicos , Treponema pallidum , Bouba/veterinária , Animais , Quênia/epidemiologia , Prevalência , Primatas , Vigilância em Saúde Pública , Treponema pallidum/imunologia
14.
Acta Trop ; 196: 42-47, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31077641

RESUMO

Over the past decade, insecticide resistance to malaria vectors has been identified in 71 malaria endemic countries. This has posed a major global health challenge in the fight against malaria, with declining rates of indoor residual spraying coverage attributed to pyrethroid-resistance. As part of its vector control monitoring strategies, the Bioko Island Malaria Control Project (BIMCP) in Equatorial Guinea conducted routine insecticide resistance bioassays using the WHO's standard susceptibility tests from 2013 to 2018. During the same period, the frequency of the target-site knockdown resistance allele (kdr) in the local vector population was also determined via PCR for detection of the L1014 F mutation. Biochemical analysis for metabolic resistance was also conducted in 2015. From 2016-2017, Fludora™ fusion, a formulated combination of clothianidin (a neonicotinoid) and deltamethrin (a pyrethroid) was evaluated for 9 months on Bioko Island, using the WHO's standard test procedure for determining residual effectiveness of insecticides on sprayed surfaces. In 2016, the mortality rate of the vectors on 0.05% deltamethrin was as low as 38%. The frequency of the West African form of knockdown resistance allele, L1014 F, in the vector population was as high as 80%, and metabolic resistance analysis indicated high upregulated cytochrome P450 s. However, the residual effectiveness of Fludora™ fusion recorded mortalities above 80% after 72 h of exposure for 8 months. Although both target-site knockdown resistance and metabolic resistance to pyrethroids were implicated in the local malaria vector population, Fludora™ fusion was effective under field conditions in controlling the resistant vectors for a period of 8 months on wooden surfaces on Bioko Island and represents a valuable addition to IRS programs, especially in regions with high levels of pyrethroid resistance.


Assuntos
Anopheles/efeitos dos fármacos , Guanidinas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrilos/farmacologia , Piretrinas/farmacologia , Tiazóis/farmacologia , Animais , Guiné Equatorial/epidemiologia , Guanidinas/administração & dosagem , Guanidinas/química , Humanos , Resistência a Inseticidas/genética , Inseticidas/administração & dosagem , Inseticidas/química , Inseticidas/farmacologia , Ilhas , Malária/epidemiologia , Malária/prevenção & controle , Neonicotinoides/administração & dosagem , Neonicotinoides/química , Nitrilos/administração & dosagem , Nitrilos/química , Piretrinas/administração & dosagem , Piretrinas/química , Tiazóis/administração & dosagem , Tiazóis/química
15.
Zoonoses Public Health ; 66(5): 480-486, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30969028

RESUMO

Twenty-six per cent of Mongolians live pastoral lifestyles, increasing their likelihood of exposure to ticks and placing them at a higher risk for contracting tick-borne diseases (TBDs). Anaplasma spp. and Rickettsia spp. have been identified in ticks, livestock and humans in Mongolia, but no known qualitative research has been conducted investigating the association between nomadic herder characteristics, tick bite history and exposure to TBDs. To better understand the association between self-reported tick bites and symptoms versus actual exposure to TBDs, this study paired serological data with 335 surveys administered to Mongolian herders, ages 12-69, from 2014 to 2015. Logistic regression results identified no significant associations between reported tick bites or symptoms with serological evidence of Anaplasma spp. and Rickettsia spp. controlling for age, gender and aimag. Among the 335 respondents who were seropositive to either Anaplasma spp. or Rickettsia spp., 32.9% self-reported experiencing abnormal symptoms such as redness, inflammation, headache, arthritis or fever after being bitten. Alternatively, 17.3% (58/335) of individuals reported experiencing symptoms following a tick bite in instances where serological results indicated no exposure to Anaplasma spp. or Rickettsia spp. Results also identified inconsistencies in reporting and seroprevalence among different age groups, with children having the highest reporting and treatment seeking rates but low levels of exposure in comparison with other groups. While survey results showed that individuals were aware of peak tick seasons and tick species that inhabit specific areas, 58% of heads of households (49/84) were unaware that ticks can cause disease in livestock or dogs. This study suggests that herders are an at-risk population in Mongolia with gaps in awareness of TBD risk. Increased surveillance paired with focused outreach to prevent TBDs targeted to the herder population is encouraged.


Assuntos
Anaplasmose/epidemiologia , Infecções por Rickettsia/epidemiologia , Picadas de Carrapatos/epidemiologia , Migrantes , Adolescente , Adulto , Idoso , Anaplasma/imunologia , Anaplasmose/sangue , Anaplasmose/transmissão , Criação de Animais Domésticos , Animais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mongólia/epidemiologia , Rickettsia/imunologia , Infecções por Rickettsia/sangue , Infecções por Rickettsia/transmissão , Estações do Ano , Carrapatos/classificação , Adulto Jovem , Zoonoses/epidemiologia
16.
J Med Entomol ; 56(4): 1071-1077, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-30882148

RESUMO

Sustaining high levels of indoor residual spraying (IRS) coverage (≥85%) for community protection against malaria remains a challenge for IRS campaigns. We examined biting rates and insecticide resistance in Culex species and Anopheles gambiae s.l., and their potential effect on community adherence to IRS. The average IRS coverage in urban Malabo between 2015 and 2017 remained at 80%. Culex biting rate increased 6.0-fold (P < 0.001) between 2014 and 2017, reaching 8.08 bites per person per night, whereas that of An. gambiae s.l. remained steady at around 0.68. Although An. gambiae s.l. was susceptible to carbamates and organophosphates insecticides, Culex spp. were phenotypically resistant to all four main classes of WHO-recommended IRS insecticides. Similarly, the residual activity of the organophosphate insecticide used since 2017, ACTELLIC 300CS, was 8 mo for An. gambiae s.l., but was almost absent against Culex for 2 mo post-spray. A survey conducted in 2018 within urban Malabo indicated that 77.0% of respondents related IRS as means of protection against mosquito bites, but only 3.2% knew that only Anopheles mosquitoes transmit malaria. Therefore, the increasing biting rates of culicines in urban Malabo, and their resistance to all IRS insecticides, is raising concern that a growing number of people may refuse to participate in IRS as result of its perceived failure in controlling mosquitoes. Although this is not yet the case on Bioko Island, communication strategies need refining to sensitize communities about the effectiveness of IRS in controlling malaria vectors in the midst of insecticide resistance in nonmalaria vector mosquitoes.


Assuntos
Culex , Resistência a Inseticidas , Controle de Mosquitos , Animais , Cidades , Guiné Equatorial , Comportamento Alimentar , Malária/prevenção & controle , Malária/transmissão
17.
Ecohealth ; 16(2): 330-337, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30825021

RESUMO

Years when the deer population is robust during the autumn hunting season may point toward an elevated risk of Lyme disease (LD) in the human population two summers later. We applied overdispersed Poisson regression models to county-specific data from New Jersey for each year from 2000 to 2014. The average relative risk of LD for each additional hunter-killed deer per square mile was 1.12 (1.10, 1.14) for 2000-2007 and 1.11 (1.09, 1.13) for 2008-2014. The hunting data already collected for conservation and wildlife management purposes may be a relevant component of LD surveillance activities.


Assuntos
Cervos/microbiologia , Doença de Lyme/epidemiologia , Animais , Animais Selvagens/microbiologia , Conservação dos Recursos Naturais/estatística & dados numéricos , Humanos , New Jersey/epidemiologia , Dinâmica Populacional , Tempo (Meteorologia)
18.
Vector Borne Zoonotic Dis ; 19(9): 658-661, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30835648

RESUMO

Introduction: In Asia, Borrelia garinii, B. afzelii, and B. bavariensis are transmitted by Ixodes persulcatus ticks and clinically present with a wide range of neurological and arthritic symptoms. This report aims to provide details on the geographic distribution of suspected cases of Lyme borreliosis (LB), reported to local Mongolian hospitals between 2007 and 2017. Methods: This report examines 150 reported cases of suspected LB from 13 aimags (provinces) in Mongolia from April 2007 to August 2017, including date and location of infection, method of diagnosis (indirect immunofluorescent assay and/or enzyme-linked immunosorbent assay test), frequency of specific symptoms, and case demographics. Information was gathered through collaboration with the National Center of Communicable Disease and the National Center for Zoonotic Diseases. Results: Zavkhan and Selenge, located in northern Mongolia, had the highest percentage of reported suspected cases, with 25% and 20%, respectively. Ages ranged from 1 to 78 years, with a mean age of 26 years, however, 37% of individuals were younger than 10. More than twice as many women sought treatment as men, and the distribution of men who sought treatment was skewed toward children and the elderly. Most frequently reported symptoms include fever, rash, headache, and enlarged lymph glands. Furthermore, peak months of tick bite and treatment seeking occurred between April and June. Conclusions: Based on these preliminary findings, syndromic surveillance should be expanded across northern Mongolia, with LB considered in differential diagnosis for patients reporting a recent tick bite.


Assuntos
Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Adolescente , Adulto , Idoso , Animais , Borrelia/classificação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mongólia/epidemiologia , Estudos Retrospectivos , Adulto Jovem
19.
Am J Trop Med Hyg ; 99(5): 1222-1228, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30226137

RESUMO

Burkholderia pseudomallei, the etiological agent of melioidosis, has been hypothesized to be endemic throughout the Caribbean, including the impoverished nation of Haiti. However, because of the protean clinical manifestations, presence of asymptomatic infections, and limited medical diagnostic capacity, the identification of active melioidosis cases remains challenging. A seroepidemiological study was conducted using a novel enzyme-linked immunosorbent assay (ELISA) to detect antibodies toward B. pseudomallei in the native population. The performance of an indirect ELISA with purified lipopolysaccharide (LPS) from B. pseudomallei was evaluated using serum collected from rhesus macaques exposed to aerosolized B. pseudomallei. After optimization, serum collected from asymptomatic population members (n = 756) was screened for polyvalent (immunoglobulin M [IgM]/ immunoglobulin G [IgG]/ immunoglobulin A) and monoclonal (IgG or IgM) immunoglobulins against B. pseudomallei LPS. The population seroprevalence was 11.5% (95% confidence interval [CI]: 9.2, 13.8) for polyvalent immunoglobulins, 9.8% (95% CI: 7.7, 11.9) for IgG, and 1.7% (95% CI: 0.8, 2.6%) for IgM. The seroprevalence was not significantly different by gender (P = 0.16), but increased significantly (P < 0.001) with age, yielding an estimated annual seroconversion rate of 1.05% (95% CI: 0.81, 1.3). The detection of both recent (IgM+) and previous (IgG+) exposure to B. pseudomallei provides serological evidence that melioidosis is endemic in Haiti.


Assuntos
Anticorpos Antibacterianos/sangue , Burkholderia pseudomallei/imunologia , Melioidose/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Infecções Assintomáticas/epidemiologia , Criança , Pré-Escolar , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática , Feminino , Haiti/epidemiologia , Humanos , Lipopolissacarídeos , Macaca mulatta/imunologia , Masculino , Melioidose/imunologia , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
20.
PLoS Negl Trop Dis ; 12(8): e0006696, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30148847

RESUMO

Transstadial transmission of tick-borne rickettsiae has been well documented. Few studies, however, have evaluated the role of transovarial transmission of tick-borne rickettsiae, particularly in nature within the host-vector ecosystem. This cross-sectional study aimed to understand the role of transovarial transmission of tick-borne rickettsiae among feeding ticks at different life stages. Tick eggs laid by engorged wild-caught adult female ticks were pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. using molecular techniques, while adult fed ticks were tested individually. Additionally, larval and nymphal ticks were collected in the wild from small mammals, pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. There were 38 fed adult and 618 larvae/nymphs (60 pools total) Dermacentor spp. ticks collected from livestock and rodents. All individual adult ticks and tick pools were positive for Rickettsia spp. While none of the larvae/nymphs were positive for Anaplasma/Ehrlichia spp., two adult fed ticks were positive. Rickettsia spp. DNA was detected in 91% (30/33) of the pooled eggs tested, and one pool of eggs tested positive for Anaplasma/Ehrlichia spp. Sequencing data revealed Rickettsia spp. shared ≥99% identity with R. raoultii ompA. Anaplasma/Ehrlichia spp. shared ≥89% identity with A. ovis 16S ribosomal RNA. This study identified potential transovarial transmission of Rickettsia spp. and Anaplasma spp. among D. nuttalli ticks. Additional studies are needed to further assess the proportion of transovarial transmission occurring in nature to better understand the burden and disease ecology of tick-borne rickettsiae in Mongolia.


Assuntos
Dermacentor/microbiologia , Rickettsia/fisiologia , Animais , Feminino , Interações Hospedeiro-Patógeno , Larva/microbiologia , Mongólia , Ninfa/microbiologia , Ovário/microbiologia
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