On June 11, 2009, the World Health Organization declared a global influenza pandemic due to a novel influenza A virus subtype of H1N1. Public health emergencies, such as an influenza pandemic, can potentially impact disadvantaged populations disproportionately due to underlying social factors. Canada???s First Nation population was severely impacted by the 2009 H1N1 influenza pandemic. Most First Nation communities suffer from poor living conditions, impoverished lifestyles, lack of access to adequate health care, and uncoordinated health care delivery. Also, there are vulnerable populations who suffer from co-morbidities who are at a greater risk of falling ill. Moreover, First Nation communities that are geographically remote (nearest service center with year-round road access is located over 350 kilometers away) and isolated (only accessible by planes year-round) face additional challenges. For example, transportation of supplies and resources may be limited, especially during extreme weather conditions. Therefore, remote and isolated First Nation communities face unique challenges which must be addressed by policy planners in order to mitigate the injustice that may occur during a public health emergency. The Assembly of First Nations noted that there has been very little inclusion of First Nations??? input into current federal and provincial pandemic plans. Disadvantaged groups know best how they will be affected by a public health emergency and are able to identify barriers and solutions. Therefore, the objective of my research was to gain retrospective insight into the barriers faced by three remote and isolated First Nation communities of sub-arctic Ontario (i.e., Fort Albany, Attawapiskat, and Kashechewan) during their 2009 H1N1 pandemic response. Culturally-appropriate community-based suggestions for improvement of existing community-level pandemic plans were also elicited. Collected data informed modifications to community-level pandemic plans, thereby directly applying research findings. Being a qualitative community-based participatory study, First Nation community members were involved in many aspects of this research. Semi-directed interviews were conducted with adult key informants (n=13) using purposive sampling of participants representing the three main sectors responsible for health care services (i.e., federal health centers, provincial hospitals, and Band Councils). Data were manually transcribed and coded using deductive and inductive thematic analysis to reveal similarities and differences experienced within and between each community (and government body) regarding their respective pandemic response. Another round of semi-directed interviews (n=4) and community pandemic committee meetings were conducted to collect additional information to guide the modifications to the community-level pandemic plans. Reported barriers due to being geographically remote and isolated included the following: overcrowding in houses, insufficient human resources, and inadequate community awareness. Primary barriers faced by government bodies responsible for health care delivery were reported as follows: receiving contradicting governmental guidelines and direction from many sources, lack of health information sharing, and insufficient details in community-level pandemic plans. Suggested areas for improvement included increasing human resources (i.e., nurses and trained health care professionals), funding for supplies, and community awareness. Additionally, participants recommended that complementary communication plans should be developed. As suggested by participants, community-specific information was added to update community-level pandemic plans. Remote and isolated First Nation communities faced some barriers during their 2009 H1N1 health sector pandemic response. Government bodies should focus efforts to provide more support in terms of human resources, monies, and education. In addition, various government organizations should collaborate to improve housing conditions, timely access to resources, and the level of coordination regarding health care delivery. Furthermore, as pandemic plans are dynamic, government bodies should continue to aide First Nation communities with updating their community-level pandemic plans to satisfy their evolving needs. These recommendations should be addressed so that remote and isolated western James Bay First Nation communities and other similar communities can be better prepared for the next public health emergency.

During the 2009 H1N1 influenza pandemic, public health nurses (PHNs) were called upon to protect their communities against a deadly influenza virus. Currently, there appears to be no literature that describes the experience of Canadian PHNs responding to the first influenza pandemic of the 21st century. A qualitative research study was conducted and the data were analyzed by using content analysis. Thirteen nurses were interviewed from an Urban, Rural and Northern health region in Manitoba. Focus groups were conducted for the Urban and Rural nurses while Northern nurses were interviewed by telephone. Communication and dissemination of information, personal and professional challenges, personal face of the pandemic, regional support and lessons learned were themes generated from the data analysis. Communication and information flow was a major theme that impacted the overall PHNs’ response experience. Practice, administration, research and education implications and the limitations of the study are presented in the study.

This work builds on the use of several Mathematical Modeling tools to develop approaches that address relevant, real and previously unanswered questions related to the improvement of Public Health Systems, in three particular instances. First, this thesis analyzes the variation in state-level vaccination coverage during the emergency response to the 2009 H1N1 pandemic influenza outbreak in the United States. The analysis considers the overall adults population and two priority sub-populations: children and high-risk adults. We focus on quantifying the association between vaccination coverage and the supply chain and distribution system decisions, during the vaccine shortage period, while controlling for other commonly recognized factors such as previous vaccinations, socio-economic characteristics, health seeking behavior and health infrastructure. The variables analyzed are generally correlated, and the problem has a limited sample size with a much larger number of independent variables. The findings of this research have been published in Vaccine and presented to the Centers for Disease Control and Prevention. Second, the research approaches the problem of estimating childhood obesity prevalence in small geographic areas in the U. S. Obesity is recognized as one of the major health problems in the country, and attending this condition in children is of major importance to deal with the sources of the overall problem. The ability to target interventions to the most affected children populations is necessary to achieve cost effective solutions. But local accurate obesity data is hard to obtain and missing for most of the small areas in the country. The research focuses on estimating prevalence of obesity and overweight status in children in small geographical areas in the absence of surveillance and detailed sampling. Our modeling approach is built in two stages. The first one uses a logistic regression model that links individual characteristics to high-BMI status, and generates samples of the empirical distribution of its coefficients though bootstrap re-sampling. The second uses simulation to generate virtual population samples of the small areas, which are then combined with the logistic model samples to estimate prevalence. Confidence intervals are built though re-sampling. A very important feature of our approach is that all of its inputs are from publicly available data, which gives availability for the replication of the methodology to any health stakeholder in the US. The model estimates were validated by using separate models for adults and children in a state with available data. Estimates obtained from our modeling approach were used by a large healthcare provider to geographically target interventions for pediatric obesity. Third, the thesis presents an introductory analysis of the possible effects of partial disruptions to critical supply chains due to absenteeism caused by a generalized flu-like illness in the US. For this analysis, we first construct a plausible national food supply chain for milk and then we simulate its disruption. To build the supply chain we used public information regarding production, consumption, and major milk processors and bottlers, and fitted it into a supply network though optimization. Then, to analyze the effects of flow disruptions of the supply chain, we built a simulation of the operation of the network and virtually generated absenteeism, mildly disrupting the supply chain flows by the proportional absences. We used information on potential absenteeism in work groups from an influenza simulator. Our initial analysis shows that absenteeism may create variations along the supply chain, similar to those described in the bullwhip effect analysis literature, even in the absence of supply shortages and without variations in pricing or demand, for which we find no prior reference in the literature.

published_or_final_version / Community Medicine / Doctoral / Doctor of Philosophy

published_or_final_version / Public Health / Master / Master of Public Health

Submitted by admin tede (tede@pucgoias.edu.br) on 2018-11-19T16:59:56Z No. of bitstreams: 1 GISELLE ANGÉLICA MOREIRA DE SIQUEIRA.pdf: 1650143 bytes, checksum: 0a85747b640c1ee6d3c2dc446dececf7 (MD5) / Made available in DSpace on 2018-11-19T16:59:56Z (GMT). No. of bitstreams: 1 GISELLE ANGÉLICA MOREIRA DE SIQUEIRA.pdf: 1650143 bytes, checksum: 0a85747b640c1ee6d3c2dc446dececf7 (MD5) Previous issue date: 2013-12-19 / SIQUEIRA, Giselle Angelica Moreira de. Epidemic Influenza A (H1N1) 2009 in the state of Goiás/Brazil: cases and deaths. Dissertation (MSc in Environmental Sciences) – Catholic University of Goiás, Goiânia, 2013. Between late March and early April 2009, were the first reported cases of human infection caused by a new viral subtype Influenza A (H1N1) in Southern California and near San Antonio, Texas, USA, and then in Mexico and Canada. Until July 6, 2009, 905 cases were confirmed by the Ministry of Health, with reports of 23 states and the Federal District. This study described the profile of confirmed cases and deaths affected by Influenza A ( H1N1 ) in 2009 in the state of Goias and Brazil through a descriptive ecological study of confirmed cases and deaths affected by Influenza A virus (H1N1) 2009 in the State of Goias and Brazil between epidemiological weeks 16 th to 52 th, variables of research Influenza record, feeding SINAN Influenza Web were selected such as epidemiological week, age, gender, education, signs and symptoms, comorbidities, vaccination status, hospitalizations and evolution. Among the total number of cases reported during the epidemic , more than 45% were confirmed Influenza A (H1N1) in Goiás and in Brazil , with 14.9% and 3.9% subsequently died respectively. Females were predominant, those over 6 % were pregnant. The age range was found between 15 and 45 years, with the primary and secondary school levels observed schooling. Among the signs and symptoms , more than 95% of cases and deaths had fever, cough and dyspnoea, less than 30% had comorbid conditions, the occurrence of hospitalizations of cases was 96% and 45% in Goiás in Brazil, while hospitalization those who subsequently died was above 96%, less than 14% of cases and deaths have taken the vaccine against influenza (H1N1). It was concluded that it was possible to know the profile of cases and deaths from socio demographic and clinical characteristics during the epidemic period Influenza (H1N1) 2009 in Goias and Brazil, many lessons were learned that will assist in the consolidation of plans to tackle the unusual situations of epidemic and pandemic character and guide the development of public policies that will strengthen the surveillance system of disease, health care, implementation of laboratory diagnosis, mass vaccination and personal protection and respiratory hygiene network. / SIQUEIRA, Giselle Angélica Moreira de. Epidemia da Influenza A (H1N1) 2009 no estado de Goiás/Brasil: casos e óbitos. Dissertação (Mestrado em Ciências Ambientais) – Pontifícia Universidade Católica de Goiás, Goiânia, 2013. Entre o final de março e começo de abril de 2009, foram notificados os primeiros casos de infecção humana causada por um novo subtipo viral Influenza A (H1N1), no sul da Califórnia e próximo de San Antonio, no Texas, Estados Unidos, e, em seguida, no México e Canadá. Até o dia 06 de julho de 2009, 905 casos foram confirmados pelo Ministério da Saúde, com notificações de 23 estados e do Distrito Federal. Neste estudo foi descrito o perfil dos casos confirmados e óbitos acometidos por Influenza A (H1N1) em 2009 no Estado de Goiás e Brasil por meio de um estudo ecológico descritivo dos casos confirmados e óbitos acometidos pelo vírus Influenza A (H1N1) 2009 no Estado de Goiás e Brasil entre as semanas epidemiológicas 16ª a 52ª, foram selecionadas variáveis da ficha de investigação de Influenza, que alimenta o SINAN Influenza Web tais como semana epidemiológica, faixa etária, gênero, escolaridade, sinais e sintomas, comorbidades, situação vacinal, hospitalizações e evolução. Dentre o total de casos notificados durante a epidemia, mais de 45% foram confirmados por Influenza A (H1N1) em Goiás e no Brasil, sendo que 14,9% e 3,9% evoluíram para o óbito respectivamente. O gênero feminino foi predominante, destas mais de 6% eram gestantes. A faixa etária encontrada foi entre 15 a 45 anos, sendo o ensino médio e fundamental os níveis de escolaridade constatados. Dentre os sinais e sintomas, mais de 95% dos casos e óbitos apresentaram febre, tosse e dispneia, menos de 30% apresentaram comorbidades, a ocorrência de hospitalizações dos casos foi de 96 % em Goiás e 45% no Brasil, enquanto que a hospitalização dos que evoluíram para o óbito foi acima de 96%, menos de 14% dos casos e óbitos tomaram a vacina contra a Influenza (H1N1). Concluiu-se que foi possível conhecer o perfil de casos e óbitos a partir das características sócio demográficas e clínicas durante o período epidêmico da Influenza (H1N1) 2009 em Goiás e no Brasil, foram aprendidas muitas lições que auxiliarão na consolidação de planos de enfrentamento a situações inusitadas de caráter epidêmico e pandêmico e norteará a construção de políticas públicas que fortalecerá o sistema de vigilância da doença, da rede de atenção à saúde, implementação de diagnóstico laboratorial, vacinação massiva e medidas de proteção individual e higiene respiratória.

The recent experience with the 2009 H1N1 pandemic has drawn attention to the need to better understand the public’s response to emergently released vaccines (ERV). This study applied a mixed methods approach to examine the causal pathways underlying the vaccination behaviour during a public health emergency. The integrated evidence from empirical and theoretical-based findings highlights a number of factors to consider in interventions to improve vaccination rates with an ERV. These factors include: 1) providing clear risk messages around the disease and the ERV, 2) improving accessibility to the vaccine, 3) encouraging primary healthcare providers to provide recommendations for vaccination, 4) implementing strategies to increase seasonal influenza vaccination prior to the next public health emergency, 5) developing strategies to target sub-populations more reluctant to accept an ERV. Developing theory-based interventions that are behaviour-specific may be more likely to result in behaviour change within the public in future emergency vaccination campaigns.

The recent experience with the 2009 H1N1 pandemic has drawn attention to the need to better understand the public’s response to emergently released vaccines (ERV). This study applied a mixed methods approach to examine the causal pathways underlying the vaccination behaviour during a public health emergency. The integrated evidence from empirical and theoretical-based findings highlights a number of factors to consider in interventions to improve vaccination rates with an ERV. These factors include: 1) providing clear risk messages around the disease and the ERV, 2) improving accessibility to the vaccine, 3) encouraging primary healthcare providers to provide recommendations for vaccination, 4) implementing strategies to increase seasonal influenza vaccination prior to the next public health emergency, 5) developing strategies to target sub-populations more reluctant to accept an ERV. Developing theory-based interventions that are behaviour-specific may be more likely to result in behaviour change within the public in future emergency vaccination campaigns.

No description available.

Influenza virus belongs to the Orthomyxovirus family of viruses that causes respiratory infection in humans, leading to morbidity and mortality. The mature influenza A virion has an envelope that contains two major surface glycoproteins proteins – hemagglutinin (HA) and neuraminidase (NA). HA is a highly antigenic molecules and is responsible binding to host cell surface receptors (Sialic acid), and membrane fusion between the viral membrane and the host endosomal membrane. Most of the antibody response generated against influenza virus either by vaccination or by natural infection is directed against HA. Influenza virus has segmented negative–sense RNA genome which gives the virus the ability to evade the host immune response by incorporating mutations (antigenic drift) and/or by reassotment with other subtypes of influenza A viruses (antigenic shift). Currently licensed vaccines which include an inactivated vaccine, a live attenuated vaccine, and recombinant subunit vaccine are beneficial for providing protection against seasonal influenza viruses that are closely related to the vaccine strain but fail to provide protection against drifted strains. This limits their breadth of protection and thus requires annual revaccination with reformulated vaccines. Also, because selection of a vaccine strain for the next season is purely based on surveillance and prediction, sometimes mismatches do happen between the selected vaccine strains and circulating viruses, resulting in a drastic decrease in vaccine efficacy and thus high morbidity and mortality. Furthermore, the production of these seasonal vaccines takes 6-8 months on an average, and does not guarantee protection against infection with novel reassortant viruses which can cause pandemics. To overcome the draw-backs of seasonal influenza virus vaccines and to enhance our pandemic preparedness, there is an increasing need for game-changing influenza virus vaccines that can confer robust, long-lasting protection against a broad spectrum of influenza virus isolates. Influenza hemagglutinin (HA) is highly immunogenic and thus a major target for vaccine design. HA is synthesized as a precursor polypeptide (HA0), assembles into a trimer, matures by proteolytic cleavage along the secretory pathway and is transported to the cell surface. Mature HA has a globular head domain, primarily composed of the HA1 subunit, which mediates receptor binding, while the stem domain, predominantly comprises of the HA2 subunit, and houses the fusion peptide. At neutral pH, the HA stem is trapped in a metastable state but undergoes an extensive conformational rearrangement at low pH in the late endosome (host-cell endosome) to trigger the fusion of virus and host membranes. Clusters of ‘antigenic sites’ have been identified in the head domain of HA, indicating that it harbors an almost continuous carpet of epitopes that are targeted by antibodies. However, these immunodominant sites constantly accumulate mutations to escape immune pressure, and thereby narrow the breadth of head-directed neutralizing antibodies (nAbs). In contrast to the highly-variable head domain, the membrane-proximal HA stem subdomain has much less sequence variability and, thus, is a desirable target for influenza vaccine development. In the recent past, several broadly neutralizing antibodies (bnAbs) targeting this subdomain with neutralizing activity against diverse influenza A virus subtypes have been isolated from infected people, further proving that this subdomain of HA can be targeted as a vaccine candidate. Steering the immune response towards this conserved, subimmunodominant stem subdomain in the presence of the variable immunodominant head domain of HA has been quite challenging. Alternatively, mimicking the epitome of these stem-directed bnAbs in the native, pre-fusion conformation in a ‘headless’ stem immunogenic capable of eliciting a broadly protective immune response has been difficult because of the metastable nature of HA. Addressing the aforementioned challenges, here we describe the design, stabilization and characterization of novel stem derived immunogens from HA of influenza A viruses using a protein minimization approach. Chapter 1 gives an overview of the influenza virus life cycle, nomenclature and classification of influenza virus; outlines the structural organization and functional properties of different viral proteins. An introduction to the kind of immune responses generated during vaccination or natural infection with the virus is discussed. The conventional vaccines that are currently used and their limitations, recent progress in the field of novel vaccine developmental approaches targeting the conserved epitopes on HA, is also described in this chapter. This chapter also gives a broad overview of bnAbs that have been isolated in the recent past, which target the novel antigenic signatures on HA. The design of a stem domain construct from an H3N2 virus (A/HK/68) is described in Chapter 2. In order to ensure that HA2 folds into the neutral pH conformation, regions of HA1 interacting with it were included in the design. Additionally, two Asp mutations were introduced in the B loop of HA2 to destabilize the low pH conformation and stabilize the desired native, neutral pH conformation. Studies using small peptides (57-98 of HA2) indicated that Asp mutations at positions 63 and 73 destabilized the low pH conformation. Studies on mutants with additional pairs of introduced Cys residues showed that the designed protein H3HA6 was folded into the neutral pH form. Immunization studies using mice showed that the protein was highly immunogenic and provided complete protection against a lethal dose of a homologous virus. Two constructs H3HA6a and H3HA6b, designed from the stem region of drifted H3N2 viruses (A/Phil/2/82 and A/Bris/10/07) were tested for protection against HK/68 to determine the extent of cross-strain protection provided by HA6. While HA6a (from A/Phil/2/82) provided near complete protection against HK/68, HA6b could protect against challenge only partially, possibly because of lower titers of antibodies elicited by this antigen. Studies using FcRγ chain knockout mice indicated that majority of the protection mediated by anti-HA6 antibodies was because of antibody mediated effectors functions, although neutralization as a mechanism of protection was also likely to contribute. In all the 18 subtypes of HA, the B loop contains residues that form the hydrophobic core of the extended coiled coil of the low pH form. As in the case of H3HA6, we suggest that these residues could be mutated to Asp to destabilize the low pH conformation. Two circularly permuted stem domain constructs from an H1N1 virus (A/PR/8/34) and an H5N1 virus (A/Viet/1203/04) were made. The design and characterization of these proteins is described in Chapter 3. H1HA6, H1HA0HA6 and H5HA6 were purified from inclusion bodies and refolded. The proteins H1HA6 and H1HA0HA6 were highly immunogenic and provided protection against a lethal challenge with homologous PR/8/34 virus. Anti-H1HA6 sera had higher titres of antibodies against heterogonous HAs as compared to convalescent sera. Stem derived immunogens from drifted H1N1 viruses (A/NC/20/99 and A/Cal/7/09) have been made and tested for cross-protection with PR/8/34 challenge. While H5HA6 also elicited high titers of antibodies, it could only protect partially against PR/8/34 challenge probably because high enough titers of cross-reactive protective antibodies were not elicited by this protein. These stem immunogens conferred robust subtype specific and modest heterosubtypic protection in vivo against lethal virus challenge. However, the immunogens, especially H1HA6, a stem immunogen from group 1 (PR8) virus is aggregation prone when expressed in E.coli. The strategy used to improve the biophysical and biochemical properties and thus the immunogenicity of these stem derived immunogens is discussed in Chapter 4. A random mutagenesis library of H1HA6 was constructed by error prone PCR using modified nucleotide analogues. The library was displayed on the yeast cell surface to isolate mutants showing better surface expression and improvement in binding to the broadly neutralizing antibody CR6261 compared to the wild-type protein. We isolated few clones, of which one mutant (H1HA6P2) dominated the enriched population. The other mutants differed slightly from H1HA6P2. This mutant differs from the wild-type by two mutations K314E and M317T (H1 numbering) which are close to the CR6261 binding site but outside the antibody foot-print (epitope). This mutant showed improved binding to CR6261 and exhibited significant improvement in surface expression. Improvement was also observed in binding of this mutant to F16v3-ScFv (another broadly neutralizing antibody). Two cysteine mutations were also introduced to further stabilize the trimeric form of the protein. Chapter 5 describes the biophysical and biochemical characterization of the high affinity isolated mutant at the protein level. We expressed this affinity matured mutant gene in E.coli and purified the protein from inclusion bodies. The stabilized mutant protein showed remarkable improvement in biophysical and biochemical properties and was recognized by stem directed conformation sensitive broadly neutralizing antibodies CR6261, F10 and F16v3 with affinity comparable to the full-length HA ectodomain. These results clearly suggest that this mutant protein is properly folded in its native pre-fusion conformation and thus can be an excellent candidate for eliciting stem directed broadly neutralizing antibodies. All these stabilized versions of stem derived immunogens will be tested for immunogenicity and cross-protection with different viral challenges. Chapter 6 describes the development of a method for mapping antibody epitopes (especially conformational epitopes) down to the residue level. Using a panel of single cysteine mutants, displayed on the yeast cell surface, this bypasses the need for laborious and time consuming protein purifications steps used in conventional methods for epitope mapping. We made a panel of single cysteine mutants, covering the entire surface of the antigen (CcdB, a bacterial toxin protein), displayed each mutant individually as well as in a pool, representing all mutants together on the yeast cell surface, and covalently labeled the cysteine with biotin-PEG2-maleimide to mask the area. The effect on antibody binding was monitored to identify the residues and relative positions important for antibody interactions with the displayed antigen by flow cytometry. By using this method we were able to map the conformational as well as linear epitopes of a panel of monoclonal antibodies down to the residue level with ease, and also identify the regions on the antigen which contribute to the antigen city during immunization in different animals. Since, this method is quite easy, rapid and gives in-depth information about antigenic epitopes, it can be useful in rational design of epitomes specific vaccines and other antibody therapeutics. It can easily be extended to other display systems and is a general approach to probe macromolecular interfaces.