Overview of latest articles and publications on ebola in PubMed. PubMed is a service of the US National Library of Medicine that includes over 18 million citations from MEDLINE and other life science journals.
- Vector status of Aedes species determines geographical risk of autochthonous Zika virus establishment.
Vector status of Aedes species determines geographical risk of autochthonous Zika virus establishment. [Journal Article]PLoS Negl Trop Dis 2017 Mar 24; 11(3):e0005487.PNGardner L, Chen N, Sarkar S Results from the analysis reveal that if Ae. aegypti is the only competent Zika vector, then risk is geographically limited; in North America mainly to Florida and Texas. However, if Ae. albopictus pro...Publisher Full TextThe 2015-16 Zika virus pandemic originating in Latin America led to predictions of a catastrophic global spread of the disease. Since the current outbreak began in Brazil in May 2015 local transmission of Zika has been reported in over 60 countries and territories, with over 750 thousand confirmed and suspected cases. As a result of its range expansion attention has focused on possible modes of transmission, of which the arthropod vector-based disease spread cycle involving Aedes species is believed to be the most important. Additional causes of concern are the emerging new links between Zika disease and Guillain-Barre Syndrome (GBS), and a once rare congenital disease, microcephaly.Like dengue and chikungunya, the geographic establishment of Zika is thought to be limited by the occurrence of its principal vector mosquito species, Ae. aegypti and, possibly, Ae. albopictus. While Ae. albopictus populations are more widely established than those of Ae. aegypti, the relative competence of these species as a Zika vector is unknown. The analysis reported here presents a global risk model that considers the role of each vector species independently, and quantifies the potential spreading risk of Zika into new regions. Six scenarios are evaluated which vary in the weight assigned to Ae. albopictus as a possible spreading vector. The scenarios are bounded by the extreme assumptions that spread is driven by air travel and Ae. aegypti presence alone and spread driven equally by both species. For each scenario destination cities at highest risk of Zika outbreaks are prioritized, as are source cities in affected regions. Finally, intercontinental air travel routes that pose the highest risk for Zika spread are also ranked. The results are compared between scenarios.Results from the analysis reveal that if Ae. aegypti is the only competent Zika vector, then risk is geographically limited; in North America mainly to Florida and Texas. However, if Ae. albopictus proves to be a competent vector of Zika, which does not yet appear to be the case, then there is risk of local establishment in all American regions including Canada and Chile, much of Western Europe, Australia, New Zealand, as well as South and East Asia, with a substantial increase in risk to Asia due to the more recent local establishment of Zika in Singapore.
- Rapid Surveillance for Vector Presence (RSVP): Development of a novel system for detecting Aedes aegypti and Aedes albopictus.
Rapid Surveillance for Vector Presence (RSVP): Development of a novel system for detecting Aedes aegypti and Aedes albopictus. [Journal Article]PLoS Negl Trop Dis 2017 Mar 24; 11(3):e0005505.PNMontgomery BL, Shivas MA, Hall-Mendelin S, et al. RSVP can rapidly detect nucleic acids from low numbers of target species within large samples of endemic species aggregated from multiple ovitraps. This screening capability facilitates deployment of o...Publisher Full TextThe globally important Zika, dengue and chikungunya viruses are primarily transmitted by the invasive mosquitoes, Aedes aegypti and Aedes albopictus. In Australia, there is an increasing risk that these species may invade highly urbanized regions and trigger outbreaks. We describe the development of a Rapid Surveillance for Vector Presence (RSVP) system to expedite presence- absence surveys for both species.We developed a methodology that uses molecular assays to efficiently screen pooled ovitrap (egg trap) samples for traces of target species ribosomal RNA. Firstly, specific real-time reverse transcription-polymerase chain reaction (RT-PCR) assays were developed which detect a single Ae. aegypti or Ae. albopictus first instar larva in samples containing 4,999 and 999 non-target mosquitoes, respectively. ImageJ software was evaluated as an automated egg counting tool using ovitrap collections obtained from Brisbane, Australia. Qualitative assessment of ovistrips was required prior to automation because ImageJ did not differentiate between Aedes eggs and other objects or contaminants on 44.5% of ovistrips assessed, thus compromising the accuracy of egg counts. As a proof of concept, the RSVP was evaluated in Brisbane, Rockhampton and Goomeri, locations where Ae. aegypti is considered absent, present, and at the margin of its range, respectively. In Brisbane, Ae. aegypti was not detected in 25 pools formed from 477 ovitraps, comprising ≈ 54,300 eggs. In Rockhampton, Ae. aegypti was detected in 4/6 pools derived from 45 ovitraps, comprising ≈ 1,700 eggs. In Goomeri, Ae. aegypti was detected in 5/8 pools derived from 62 ovitraps, comprising ≈ 4,200 eggs.RSVP can rapidly detect nucleic acids from low numbers of target species within large samples of endemic species aggregated from multiple ovitraps. This screening capability facilitates deployment of ovitrap configurations of varying spatial scales, from a single residential block to entire suburbs or towns. RSVP is a powerful tool for surveillance of invasive Aedes spp., validation of species eradication and quality assurance for vector control operations implemented during disease outbreaks.
- Elongated and shortened peptidomimetic inhibitors of the proprotein convertase furin.
Elongated and shortened peptidomimetic inhibitors of the proprotein convertase furin. [Journal Article]ChemMedChem 2017 Mar 23.CHardes K, Ivanova T, Thaa B, et al. Novel elongated and shortened derivatives of the peptidomimetic furin inhibitor phenylacteyl-Arg-Val-Arg-4-amidinobenzylamide were synthesized. The most potent compounds, e.g., Nα(carbamidoyl)Arg-Arg-V...Publisher Full TextNovel elongated and shortened derivatives of the peptidomimetic furin inhibitor phenylacteyl-Arg-Val-Arg-4-amidinobenzylamide were synthesized. The most potent compounds, e.g., Nα(carbamidoyl)Arg-Arg-Val-Arg-4-amidinobenzylamide (Ki = 6.2 pM), contain additional basic residues at the N-terminus and inhibit furin in the low picomolar range. Furthermore, to decrease the molecular weight of this inhibitor type, compounds lacking the P5-moiety were prepared. The best inhibitors of this series, 5-(guanidino)-valeroyl-Val-Arg-4-amidinobenzylamide and its P3 tert.leucine analogue, displayed Ki values of 2.50 nM and 1.26 nM, respectively. Selected inhibitors, together with our previously described 4-amidinobenzylamide derivatives as references, were tested in cell culture for their activity against furin-dependent infectious pathogens. The propagation of the alphaviruses Semliki Forest virus and chikungunya was strongly inhibited in the presence of selected derivatives. Moreover, a significant protective effect of the inhibitors against diphtheria toxin was observed. These results confirm that the inhibition of furin should represent a promising approach for a short-term treatment of acute infectious diseases.
- Building the road to a regional zoonoses strategy: A survey of zoonoses programmes in the Americas.
Building the road to a regional zoonoses strategy: A survey of zoonoses programmes in the Americas. [Journal Article]PLoS One 2017; 12(3):e0174175.PlosMaxwell MJ, Freire de Carvalho MH, Hoet AE, et al. The survey is the first comprehensive effort to date to inform the status of zoonoses programmes in LAC. The information collected here will be used to develop a regional strategy for zoonoses (both en...Publisher Full TextIn recent years, global public health security has been threatened by zoonotic disease emergence as exemplified by outbreaks of H5N1 and H1N1 influenza, SARS, and most recently Ebola and Zika. Additionally, endemic zoonoses, such as rabies, burden countries year after year, placing demands on limited finances and personnel. To survey the baseline status of the emerging and endemic zoonoses programmes of the Latin American and the Caribbean (LAC) countries, the Pan American Health Organization (PAHO) conducted a survey of priority emerging and endemic zoonoses, countries´ prioritization criteria and methodologies, and suggestions to strengthen countries capacities and regional approaches to zoonoses control.A fillable online questionnaire was sent to the zoonoses programme managers of the Ministries of Health (MOH) and Ministries of Agriculture (MAg) of 33 LAC countries from January to April of 2015. The questionnaire comprised 36 single, multiple choice and open-ended questions to inform the objectives of the survey. A descriptive exploratory analysis was completed.Fifty-four ministries (26 MOH, 25 MAg, and 3 combined responses) in 31 LAC countries responded to the survey. Within the ministries, 22 (85%) MOH, 5 (20%) MAg, and 2 (67%) combined entities indicated they had specialized zoonoses units. For endemic zoonoses, 32 of 54 ministries responded that they conduct formal prioritization exercises, most of them annually (69%). The three priority endemic zoonoses for the MOHs were leptospirosis, rabies, and brucellosis while the three priorities for the MAgs were brucellosis, rabies, and tuberculosis. Diagnosis for rabies and leptospirosis were cited as the capacities most in need of development. The most needed cross-cutting capacity was coordination between stakeholders. For emerging zoonoses, 28 ministries performed formal prioritization exercises. The top prioritization criteria were probability of introduction into the country and impact. The three priority emerging zoonoses for the MOHs were Ebola viral disease, avian influenza, and Chikungunya while for the MAgs were avian influenza, bovine spongiform encephalopathy and West Nile virus disease. Surveillance for avian influenza and Ebola, and diagnosis for BSE were quoted as the capacities most needed. For all zoonoses, the majority of respondents (69%) ranked their relationship with the other Ministry as productive or very productive, and 31% minimally productive. Many countries requested a formal regional network, better regional communication and collaboration, and integrated surveillance.The survey is the first comprehensive effort to date to inform the status of zoonoses programmes in LAC. The information collected here will be used to develop a regional strategy for zoonoses (both endemic and emerging), increase efforts, advocacy, and promote prompt identification and management of EIDs and improvement of endemic programmes.
- Spatial-temporal analysis of dengue deaths: identifying social vulnerabilities.
Spatial-temporal analysis of dengue deaths: identifying social vulnerabilities. [Journal Article]Rev Soc Bras Med Trop 2017 Jan-Feb; 50(1):104-109.RSSilva MD, Branco MD, Aquino J, et al. The use of geo-technology tools pointed to a concentration of dengue deaths in specific intra-urban areas.Publisher Full TextCurrently, dengue fever, chikungunya fever, and zika virus represent serious public health issues in Brazil, despite efforts to control the vector, the Aedes aegypti mosquito.This was a descriptive and ecological study of dengue deaths occurring from 2002 to 2013 in São Luis, Maranhão, Brazil. Geoprocessing software was used to draw maps, linking the geo-referenced deaths with urban/social data at census tract level.There were 74 deaths, concentrated in areas of social vulnerability.The use of geo-technology tools pointed to a concentration of dengue deaths in specific intra-urban areas.
- Molecular and clinical epidemiological surveillance of dengue virus in Paraíba, Northeast Brazil.
Molecular and clinical epidemiological surveillance of dengue virus in Paraíba, Northeast Brazil. [Journal Article]Rev Soc Bras Med Trop 2017 Jan-Feb; 50(1):19-26.RSGuerra-Gomes IC, Gois BM, Peixoto RF, et al. Our findings support the hypothesis that co-circulation of the four DENV serotypes may be a reason for the increased prevalence of severe forms of dengue in the years studied. This study may contribute...Publisher Full TextDespite being the most prevalent arboviral disease worldwide, dengue has been neglected lately. However, recent epidemics of arboviruses such as Zika and chikungunya in locations throughout the world have alerted health authorities to these diseases. This study evaluated the incidence pattern of dengue, its clinical characteristics, and co-circulation of serotypes from 2007 to 2015 in Paraiba State, Northeast Brazil.Data on dengue cases from 2007 to 2015 were extracted from clinical reports of the National System for Notifiable Diseases [Sistema Nacional de Agravos de Notificação (SINAN)] of Brazil provided by the Paraiba Health Department. Reverse transcription polymerase chain reaction (RT-PCR) assays for dengue serotypes were carried out on plasma samples obtained from patients with suspected dengue. The data were analysed using descriptive statistics.According to clinical features, dengue fever [n = 39,083 (70.2%)] and dengue without warning signs [n = 15,365 (27.7%)] were the most common classifications of dengue. On RT-PCR, DENV 1 was the most commonly identified serotype (80.5%) in all years studied. Co-circulation of all four DENV serotypes was observed in 2013 and 2014. Furthermore, we observed an increase in dengue notifications in 2015, possibly due to the rise of Zika and chikungunya.Our findings support the hypothesis that co-circulation of the four DENV serotypes may be a reason for the increased prevalence of severe forms of dengue in the years studied. This study may contribute to directing research, health policy, and financial resources toward reducing poorly controlled epidemic diseases.
- Potential Antivirals: Natural Products Targeting Replication Enzymes of Dengue and Chikungunya Viruses.
Potential Antivirals: Natural Products Targeting Replication Enzymes of Dengue and Chikungunya Viruses. [Journal Article, Review]Molecules 2017 Mar 22; 22(3)MOliveira AF, Teixeira RR, Oliveira AS, et al. Dengue virus (DENV) and chikungunya virus (CHIKV) are reemergent arboviruses that are transmitted by mosquitoes of the Aedes genus. During the last several decades, these viruses have been responsible ...Publisher Full TextDengue virus (DENV) and chikungunya virus (CHIKV) are reemergent arboviruses that are transmitted by mosquitoes of the Aedes genus. During the last several decades, these viruses have been responsible for millions of cases of infection and thousands of deaths worldwide. Therefore, several investigations were conducted over the past few years to find antiviral compounds for the treatment of DENV and CHIKV infections. One attractive strategy is the screening of compounds that target enzymes involved in the replication of both DENV and CHIKV. In this review, we describe advances in the evaluation of natural products targeting the enzymes involved in the replication of these viruses.
- Persistent Arthralgia Associated with Chikungunya Virus Outbreak, US Virgin Islands, December 2014-February 2016.
Persistent Arthralgia Associated with Chikungunya Virus Outbreak, US Virgin Islands, December 2014-February 2016. [Journal Article]Emerg Infect Dis 2017 Apr; 23(4):673-676.EIFeldstein LR, Rowhani-Rahbar A, Staples JE, et al. After the 2014-2015 outbreak of chikungunya virus in the US Virgin Islands, we compared the prevalence of persistent arthralgia among case-patients and controls. Prevalence was higher in case-patients ...Publisher Full TextAfter the 2014-2015 outbreak of chikungunya virus in the US Virgin Islands, we compared the prevalence of persistent arthralgia among case-patients and controls. Prevalence was higher in case-patients than controls 6 and 12 months after disease onset. Continued vaccine research to prevent acute illness and long-term sequelae is essential.
- From eggs to bites: do ovitrap data provide reliable estimates of Aedes albopictus biting females?
From eggs to bites: do ovitrap data provide reliable estimates of Aedes albopictus biting females? [Journal Article]PeerJ 2017.:e2998.PManica M, Rosà R, Della Torre A, et al. This work provides the first evidence of the possibility to predict mean number of adult biting Ae. albopictus females based on mean number of eggs and to compute the threshold of eggs/ovitrap associat...Publisher Full TextAedes albopictus is an aggressive invasive mosquito species that represents a serious health concern not only in tropical areas, but also in temperate regions due to its role as vector of arboviruses. Estimates of mosquito biting rates are essential to account for vector-human contact in models aimed to predict the risk of arbovirus autochthonous transmission and outbreaks, as well as nuisance thresholds useful for correct planning of mosquito control interventions. Methods targeting daytime and outdoor biting Ae. albopictus females (e.g., Human Landing Collection, HLC) are expensive and difficult to implement in large scale schemes. Instead, egg-collections by ovitraps are the most widely used routine approach for large-scale monitoring of the species. The aim of this work was to assess whether ovitrap data can be exploited to estimate numbers of adult biting Ae. albopictus females and whether the resulting relationship could be used to build risk models helpful for decision-makers in charge of planning of mosquito-control activities in infested areas.Ovitrap collections and HLCs were carried out in hot-spots of Ae. albopictus abundance in Rome (Italy) along a whole reproductive season. The relationship between the two sets of data was assessed by generalized least square analysis, taking into account meteorological parameters.The mean number of mosquito females/person collected by HLC in 15' (i.e., females/HLC) and the mean number of eggs/day were 18.9 ± 0.7 and 39.0 ± 2.0, respectively. The regression models found a significant positive relationship between the two sets of data and estimated an increase of one biting female/person every five additional eggs found in ovitraps. Both observed and fitted values indicated presence of adults in the absence of eggs in ovitraps. Notably, wide confidence intervals of estimates of biting females based on eggs were observed. The patterns of exotic arbovirus outbreak probability obtained by introducing these estimates in risk models were similar to those based on females/HLC (R0 > 1 in 86% and 40% of sampling dates for Chikungunya and Zika, respectively; R0 < 1 along the entire season for Dengue). Moreover, the model predicted that in this case-study scenario an R0 > 1 for Chikungunya is also to be expected when few/no eggs/day are collected by ovitraps.This work provides the first evidence of the possibility to predict mean number of adult biting Ae. albopictus females based on mean number of eggs and to compute the threshold of eggs/ovitrap associated to epidemiological risk of arbovirus transmission in the study area. Overall, however, the large confidence intervals in the model predictions represent a caveat regarding the reliability of monitoring schemes based exclusively on ovitrap collections to estimate numbers of biting females and plan control interventions.
- A smartphone-based diagnostic platform for rapid detection of Zika, chikungunya, and dengue viruses.
A smartphone-based diagnostic platform for rapid detection of Zika, chikungunya, and dengue viruses. [Journal Article]Sci Rep 2017 Mar 20.:44778.SRPriye A, Bird SW, Light YK, et al. Current multiplexed diagnostics for Zika, dengue, and chikungunya viruses are situated outside the intersection of affordability, high performance, and suitability for use at the point-of-care in resou...PMC Free Full TextPublisher Full TextCurrent multiplexed diagnostics for Zika, dengue, and chikungunya viruses are situated outside the intersection of affordability, high performance, and suitability for use at the point-of-care in resource-limited settings. Consequently, insufficient diagnostic capabilities are a key limitation facing current Zika outbreak management strategies. Here we demonstrate highly sensitive and specific detection of Zika, chikungunya, and dengue viruses by coupling reverse-transcription loop-mediated isothermal amplification (RT-LAMP) with our recently developed quenching of unincorporated amplification signal reporters (QUASR) technique. We conduct reactions in a simple, inexpensive and portable "LAMP box" supplemented with a consumer class smartphone. The entire assembly can be powered by a 5 V USB source such as a USB power bank or solar panel. Our smartphone employs a novel algorithm utilizing chromaticity to analyze fluorescence signals, which improves the discrimination of positive/negative signals by 5-fold when compared to detection with traditional RGB intensity sensors or the naked eye. The ability to detect ZIKV directly from crude human sample matrices (blood, urine, and saliva) demonstrates our device's utility for widespread clinical deployment. Together, these advances enable our system to host the key components necessary to expand the use of nucleic acid amplification-based detection assays towards point-of-care settings where they are needed most.