No description available.

Background: Arboviral diseases has reemerged in the last years affecting primarily the coast of Peru. Piura is an endemic region of Dengue, where the recent appearance of Chikungunya (CHIKV) and Zika (ZIKV) has been renewed. Aim: To assess the presence of DENV, CHIKV, and ZIKV in serum samples of patients with acute febrile illness in a locality of Piura, Peru and describe associated clinical features. Methodology: Descriptive cross-sectional study, sampling was done for convenience where it was obtained a total of 496 serum samples from patients with acute febrile illness were collected from 18 primary care centers. All samples were analyzed via real-time RT-PCR to detect DENV, CHIKV, and ZIKV. In addition, positive samples for DENV were also processed for serotypes 1 to 4 classification via RT-PCR. Results: DENV was the most common arbovirus detected in 170/496 (34.3%), followed by ZIKV in 39/496 (7.9%) and CHIKV in 23/496 (4.6%). Among the 170 samples positive for DENV, serotype 2 was the most predominant type present in 97/170 (57.1%) of samples, followed by the serotype 3 in 9/170 (5.3%). Headaches, muscle pain, and joint pain were the most common symptoms associated with fever in patients with DENV and ZIKV. No symptoms predominance was observed in patients with CHIKV. Conclusions: DENV is considered the most frequent arbovirus in Peru and the number of cases has increased dramatically in the last 5 years. However, it is not the only arbovirus that circulates along the northern coast of Peru. It has also been determined the presence of ZIKV and CHIKV in our population, which may suggest the circulation of other arboviruses that have not been detected. / Tesis

One challenge facing spatial scientists trying to support public health outreach and intervention in challenging environments is the lack of fine scale spatial data. These data are required to gain a better understanding of both physical and social systems; why disease occurs where it does, and how to disrupt it. While data options exist, including high resolution aerial imagery, remotely sensed data, and even online mapping products like Google Street View, these all come with limitations. One option that has previously been utilized to assess cholera risk is spatial video. Here it is used to map potential mosquito breeding sites in an endemic Dengue and Chikungunya, and emerging Zika impacted community. We show how this method can provide mapping support in the hands of non-specialist public health workers who, working in collaboration with out-of-area geographic information systems (GIS) teams, can identify where to target limited intervention resources. We use a case study of an impoverished informal style Nicaraguan community suffering from a high disease burden to show spatial variation in potential mosquito breeding habitats. A field team collected street-by-street spatial video data to produce fine scale risk maps of standing water and trash locations, which, when interpreted with the associated spatial video imagery, were used to suggest where intervention strategies should be targeted. We also discuss how these same data layers can be used to address other health concerns traditionally found in informal settlements.

Through the SARS-CoV-2 pandemic, it has become clear that the development of antivirals is essential for the health and wellbeing of the population. In this study, novel active site protease inhibitors against SARS-CoV-2 were tested for their inhibitory activity against the viral 3-Chymotrypsin like protease through the means of FRET based enzymatic assays. Additionally, Compound 104 targeting the NS2B-NS3 protease was tested against Zika virus through yield reduction assays as a means to assess whether these assays are suitable for the assessment of peptide hybrid compounds in Zika virus.Novel compounds against SARS-CoV-2 were screened and five of the selected six active compounds were found to inhibit the viral protease at a half-maximal inhibitory concentration (IC50) of below 0.075 µM.In Zika virus, the yield reduction assay was assessed and it was found that under the conditions tested, this assay is not suitable for the assessment of peptide hybrid compounds in Zika virus.The active novel compounds against SARS-CoV-2 should be taken for further assessment in cell based assays as the next step of development. Compound 104 should be assessed under different experimental conditions to identify whether different conditions can make this assay suitable for the intended use.

No description available.

Emerging viruses represent a significant threat to human health. Understanding the drivers of emergence, such as viral evolution, is a critical avenue to combat these pathogens. One specific group of emerging pathogens of interest is flaviviruses. Flaviviruses are arthropod-borne viruses (arbovirus) in the family Flaviviridae. The medically relevant flaviviruses can be divided into two groups – tick-borne and mosquito-borne. Included within the mosquito-borne flaviviruses group are dengue viruses 1-4 (DENV 1-4), which causes 400 million infections annually, and Zika virus (ZIKV), which caused over 128 million infections from 2013-2018. These viruses, which are cocirculating, share high sequence similarity in key antigenic regions. Because of these similarities, pre-existing immunity to DENV has been correlated with altered pathogenesis of subsequent ZIKV infections. Despite this, there has been little analysis of the effects of pre-existing DENV immunity on the evolution of subsequent flavivirus infection, despite being characterized for many other viruses. Given that mutation that could arise from cross-reactive immune selection could alter pathology or transmissibility, it is critical to assess the role of cross-reactive immune selection as an evolutionary driver. However, this line of research has historically been difficult due to the inherent toxicity of flavivirus infectious clones in bacteria. To mitigate the toxic nature of flavivirus clones, we developed several entirely in vitro workflows using a combination of rolling circle amplification (RCA) and replication cycle reaction (RCR). We demonstrated that RCA was a comparable substitute to traditional plasmid propagation using an alphavirus infection clone. We further demonstrated that RCR could be used to generate infectious clones by producing infectious clones of DENV2 and SARS-CoV-2, as well as demonstrating it could be used to introduce mutations into infectious clones by producing a D614G SARS-CoV-2 mutations. With this technology in place, we used in vitro directed evolution system, where we passaged ZIKV in convalescent patient serum to assess the role of cross-reactive immune selection as an evolutionary driver. After passaging, we performed next-generation sequencing to assess the impacts of cross-reactive immune selection on the viral populations and to identify mutations that arose post-passaging. We observed that ZIKV passaged in convalescent DENV serum had reduced diversity and divergence in the premembrane region. Within the convalescent DENV passaged population, we identified two mutations of interest with the dominant antibody binding region – E-V335I and NS1-T139A. These mutations were then introduced using our in vitro workflows. The resulting mutant viruses were then assessed for their replicative fitness in mammalian cell culture and mosquito models and their sensitivity to neutralization. We observed that while both E-V355I and NS1-T139A have increased fitness in mammalian cells, they had reduced fitness in mosquitoes. These results align with the trade-off hypothesis, which states that in a multi-host system, adaptation to one host reduces fitness in the other hosts. When we assessed the neutralization sensitivity of the mutants, we observed that while NS1-T193A was resistant to neutralization, E-V355I was more sensitive to neutralization. These results indicate that neutralization escape is not necessary for enhanced post-passaging in convalescent DENV serum. Our findings demonstrate that cross-reactive immune selection can generate several mutations with altered fitness in mammalian cells and mosquitos. This research is significant for both highlighting novel technologies to facilitate molecular virology and demonstrating that cross-reactive immune selection has the potential to alter the evolutionary trajectory of flaviviruses. This work provides critical information to understand how flaviviruses are evolving and emerging, and therefore critical information to address their threat to human health. / Doctor of Philosophy / Emerging viruses represent a significant threat to human health. We must understand what drives these viruses to adapt and evolve to respond to these threats. One virus family of extreme importance is the genera flavivirus. Flaviviruses are arthropod-borne viruses (arbovirus) that can be spread by the bites of ticks and mosquitoes. Included in the mosquito-borne flavivirus are dengue virus 1-4 (DENV1-4), which accounts for 400 million new infections annually, and Zika virus (ZIKV), which caused more than 128 million infection from 2013-2018. In addition to co-circulating, DENV 1-4 and ZIKV share several key similarities in their protein structures, which results in pre-existing DENV immunity effect how subsequent infections behave. The effect of pre-existing immunity on the evolution of these viruses has not been well established, despite similar studies being performed for other viruses. Given that the mutations that could arise from immune-driven evolution could alter disease severity or transmissibility, the impacts of immune-driven evolution must be characterized. However, the current tools available to perform this research are suboptimal, as the toxicity of flavivirus genomes hampers out ability to perform bacterial cloning, which has historically been necessary to develop and modify infectious clones. To mitigate the toxicity, we developed a "bacteria-free" workflow using emerging technologies like rolling circle amplification (RCA) and replication cycle reaction (RCR). With the technology in place, we propagated several generations of ZIKV or DENV in the presence of serum from human patients with a history of DENV infections. We then sequenced the viruses and identified mutations that arose during passaging. The mutations were then inserted using our bacteria-free workflow into infectious clones. The resulting viruses were assessed for their ability to replicate in mammalian cells, their ability to infect mosquitos, and their sensitivity to patient serum. We found that exposing ZIKV to serum from patients with pre-existing immunity to DENV can result in ZIKV developing several mutations. These mutations make the virus more effective at infecting mammalian cells and less effective at infecting mosquitos. This research is significant as it highlights novel technologies to aid researchers, and it demonstrates that pre-existing immunity has the potential to alter the evolutionary trajectory of flaviviruses. This information is critical in understanding flavivirus evolution and their emergence and therefore is critical to addressing their threat to human health.

Yes / Coronavirus is the most dangerous virus in the world wide and it can easy spread between people, animals and plants because it is existing on one strand of RNA (Ribonucleic Acid) and it can duplicate faster than any virus. The source of coronavirus is still unknown, but some sources said that it came from seafood market and other sources said that it came from bat and snakes. It starts in Wuhan; China and every day the fatality increases. The symptoms are like a SARS-CoV (acute respiratory syndrome coronavirus)) and MERS-CoV (Middle East Respiratory Syndrome Coronavirus). By using nucleotide sequence of coronavirus from NCBI (National Center for Biotechnology Information) and some programs that ran on Matlab, the results show that there are some differences and similarities between coronavirus and other viruses such as Ebola, Flu-b, Hepatitis B, HIV and Zika especially for DEBs (distinct excluded blocks) program that shows at 5bp (base pair) there is a common with slightly difference between coronavirus “cgggg” and Ebola virus “cgtgg”. The aim from this study is to find a way to help doctors and scientists to stop spreading the coronavirus or to destroy it.

Flaviviruses are a genus of vector-transmitted viruses that are nearly globally distributed, and flavivirus infections can result in life threatening diseases. Many flaviviruses such as Dengue, West Nile, yellow fever and Zika viruses are globally distributed. Zika virus (ZIKV) is a single strand positive-sense RNA virus, and its disease has been linked to Guillain Barré Syndrome (i.e., a debilitating autoimmune disorder that affects the nerves) in adults and congenital birth defects including microcephaly (i.e., a neurodevelopmental disorder due to impaired neural cell proliferation) in newborns. Insect-specific flaviviruses (ISFVs) are understudied given their apathogenic characteristics to humans and animals. However, given their close genetic relationship to vertebrate infectious flaviviruses, ISFVs can serve as a delivery system (i.e., vector) for flavivirus antigenic proteins. Aripo virus (ARPV) is a recently discovered ISFV isolated in Trinidad. We developed a chimeric Zika vaccine, Aripo-Zika, by substituting the pre-membrane and envelope genes of ZIKV into the ARPV genome. Here, we explored (i) the efficacy of Aripo-Zika (AZ) vaccination by evaluating passive transfer of maternal antibodies, (ii) the optimal dosage regimen, (iii) anti-vector immunity to the ARPV backbone, and (iv) the effects of boosters on vaccine efficacy. We also evaluated AZ safety via a co-infection study. Our results show a near linear relationship between increased dose and immunogenicity, with 1011 genome copies being the most effective minimum dose administered. Inclusion of boosters further increased the immunogenicity of AZ. Additionally, prior immunization with AZ showed minimal effects on subsequent immunization with an ARPV-West Nile virus (AWN) vaccine candidate, confirming the applicability of the ARPV backbone to multiple flavivirus vaccine candidates. In vitro co-infection of ZIKV with ARPV, and ZIKV with AZ in African green monkey kidney cells (i.e., Vero-76) indicated ARPV and AZ remain incapable of replication in vertebrate cells, even in the presence of active ZIKV replication. Altogether, our data suggests that the ARPV platform is a safe and effective strategy for the development of flavivirus vaccines. / Master of Science in Life Sciences / Vaccines are one of the best tools available since their initial conception. Vaccines have collectively increased human lifespan and reduced the burden of disease in humans and animals worldwide. Vaccine research aims to create vaccines that have a perfect balance of safety and efficacy. The goal is to produce a vaccine that can generate a strong immune response against the virus(es) of interest, while causing the least harm or side effects from the vaccine. Insect-specific viruses are viruses that infect insect cells, but are unable to replicate in humans or other vertebrate cells. The Auguste Lab has created a chimeric vaccine using the genome of an insect-specific virus called Aripo-Zika virus (AZ) that is genetically related to Zika virus. A person vaccinated with AZ is expected to develop an immune response against Zika but would not have any disease or side effects associated with a Zika infection or virus replication. In order to determine if this vaccine would be safe and effective enough to advance to clinical trials in humans, we must first determine if it is safe in smaller animal models. My studies have five central aims. First, determine the lowest dose of AZ that can be given and still be protective against Zika disease in mouse models. Second, determine if boosters are necessary and if they increase protection. Third, determine if immunity derived from vaccination can be passed down from mother to pups. Fourth, determine if Zika virus and AZ can co-exist in the same cell line without AZ replication occurring. Lastly, determine if mice can be vaccinated with AZ and subsequently with another similar Aripo virus-based vaccine (i.e., Aripo-West Nile) without changing the effectiveness of the subsequent immunization. Our results showed that AZ is able to be passed from mother to pup, 1011 genome copies is the minimum protective dose, and boosters can increase the effectiveness of AZ. We also found that AZ does not replicate in vertebrate cells when it co-exists with ZIKV and subsequent vaccination with Aripo-West Nile does not seem affect the effectiveness of either vaccine.

No description available.

Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-07-20T21:53:39Z No. of bitstreams: 1 DISSERTA??O PAULO ROBERTO finalz?o 09 03.pdf: 3626215 bytes, checksum: a916a4a7fbf307b65ccad4330d1dd18c (MD5) / Made available in DSpace on 2018-07-20T21:53:39Z (GMT). No. of bitstreams: 1 DISSERTA??O PAULO ROBERTO finalz?o 09 03.pdf: 3626215 bytes, checksum: a916a4a7fbf307b65ccad4330d1dd18c (MD5) Previous issue date: 2018-02-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Study qualitative, exploratory, with the objective of understanding the experiences of families of children with microcephaly by Zika virus. For the production of empirical data we explore the narratives of relatives contained in videos posted on the YouTube Internet platform published between 10/01/2015 and 07/31/2016, as well as narratives obtained from an in-depth interview, of the story-theme design applied in 11 family members of children with microcephaly attended at the Association of Parents and Friends of the Exceptional in Feira de Santana, as well as field diary material. The data collection took place between September and November 2017. For the treatment of the data we adopted the thematic content analysis and the iconographic analysis. The results are organized in: Article 1 - Bad news: experiences and feelings of families regarding the diagnosis of microcephaly by Zika virus; A session entitled: Understanding the family dynamics of study participants; Article 2 - "Well run, very fast ...": experiences of care of mothers of children with microcephaly by Zika; Article 3 - Family organization to take care of the child with microcephaly by z?ka virus. Microcephaly is revealed in the prenatal period, through imaging tests, or during the immediate or late postpartum. Relatives live with feelings of sadness, despair, pain, fright, commotion, disorientation and terror. After diagnosis, family members seek to understand microcephaly through internet resources, and question God's permission and the relevance of scientific knowledge. Mothers experience day-to-day organizing and cleaning the home environment, caring for their children and the specific care of the child with microcephaly, regarding lullaby, since children cry frequently, requiring the mother to spend hours with the child in the lap; Give a shower; change diapers; to feed; play; and, stimulate. They learn to differentiate cognitive, psychomotor, auditory, and visual impairments; recognize progress in the development and new needs of children; identify episodes of seizure; consider patience and attention relevant to care; and, seek to learn about new thematic and unknown terms such as calcifications. Family members build a network of solidarity and unity for the benefit of the child, family relationships are strengthened, bringing together previously conflicting relationships. Caregivers include mothers, fathers, grandparents, sisters, cousins, aunts, friends and neighbors, with the mother being the protagonist who also coordinates and defines the roles played by other people. Family members practice care that has been organized in four dimensions: "Take care"; Encourage; Access Resources and Services. We recommend that family members and health workers attend to the restriction of social interaction, weakening marital relationships, jealousy behaviors on the part of siblings, worsening of grandparents' health conditions, and financial difficulties that may affect the family of children with microcephaly. / Estudo qualitativo, do tipo explorat?rio, com objetivo de compreender as experi?ncias de fam?lias de crian?as com microcefalia por Zika v?rus. Para produ??o de dados emp?ricos exploramos as narrativas de familiares contidas em v?deos postados na plataforma virtual da internet YouTube publicados entre 01/10/2015 e 31/07/2016, e tamb?m narrativas obtidas de entrevista em profundidade, do desenho est?ria-tema aplicados em 11 familiares de crian?as com microcefalia atendidos na Associa??o de Pais e Amigos dos Excepcionais em Feira de Santana, al?m de material do di?rio de campo. A coleta de dados ocorreu entre setembro a novembro de 2017. Para tratamento dos dados adotamos a an?lise de conte?do tem?tica e a an?lise iconogr?fica. Os resultados encontram-se organizados em: Artigo 1 ? M?s not?cias: experi?ncias e sentimentos de fam?lias face o diagn?stico de microcefalia por Zika v?rus; Uma se??o intitulada: Compreendendo a din?mica familiar dos participantes do estudo; Artigo 2 ? ?Bem corrido, muito corrido...?: experi?ncias de cuidado de m?es de crian?as com microcefalia por Zika; Artigo 3 ? Organiza??o familiar para cuidar da crian?a com microcefalia por z?ka v?rus. A microcefalia ? revelada no per?odo pr?-natal, atrav?s de exames de imagens, ou durante o p?s-parto imediato ou tardio. Os familiares convivem com sentimentos de tristeza, desespero, dor, susto, como??o, desorienta??o e terror. Ap?s o diagn?stico, os familiares buscam compreender a microcefalia atrav?s dos recursos da internet, e questionam a permiss?o de Deus e a relev?ncia do conhecimento cient?fico. As m?es experienciam o dia a dia organizando e limpando o ambiente dom?stico, exercendo os cuidados aos filhos e o cuidado espec?fico ? crian?a com microcefalia, referentes a: ninar, pois as crian?as choram com frequ?ncia, necessitando que a m?e passe horas com a crian?a no colo; dar banho; trocar fralda; alimentar; brincar; e, estimular. Elas aprendem a diferenciar as defici?ncias cognitivas, psicomotoras, auditivas e visuais; reconhecem os avan?os no desenvolvimento e as novas necessidades das crian?as; identificam epis?dios de convuls?o; consideram a paci?ncia e a aten??o relevantes para o cuidado; e, buscam apreender sobre novas tem?ticas e termos desconhecidos como calcifica??es. Os familiares constroem uma rede de solidariedade e uni?o em prol da crian?a, as rela??es familiares s?o fortalecidas, aproximando rela??es antes conflituosas. Participam do cuidado as m?es, pais, av?s, irm?s (os), primos (as), tias (os), amigas e vizinhas, havendo protagonismo da m?e que tamb?m coordena e define os papeis desempenhados pelas outras pessoas. Os familiares exercem cuidados que foram organizados em quatro dimens?es: Cuidar Integralmente; ?Tomar Conta?; Estimular; Acessar Recursos e Servi?os. Recomendamos que os familiares e trabalhadores da sa?de atentem para a restri??o do conv?vio social, enfraquecimento das rela??es conjugais, comportamentos que indiquem ci?mes por parte dos irm?os, agravamento das condi??es de sa?de das av?s e dificuldades financeiras que podem repercutir na fam?lia de crian?as com microcefalia.