Influenza A Virus Pandemic - Essay Example

? Key Health Problem(s) in the Case Study Human cases of infection with 2009 pandemic influenza A (H1N1) virus first arose in the U.S. and Mexico in April 2009. The pandemic influenza surfaced in China in May 2009, and by the end of the year, more than 120,000 confirmed cases reported with 648 confirmed deaths. Influenza A (H1N1) represents the subtype of influenza A virus that detailed the most dominant cause of human influenza in 2009. Influenza A virus represent virus subtypes generated by a significant genetic reassortment (antigenic shift), or that are considerably diverse from viruses that have yielded infections over the previous several decades bear the potential to cause a pandemic (Garten, et al. 2009, p.197). The influenza morbidity generated by 2009 pandemic influenza A (H1N1) remained above seasonal baselines and yielded the first pandemic since 1968. In the U.S., the pandemic manifested a considerable increase in influenza activity as demonstrated by multiple influenza surveillance systems (Jhung 2011, p.13). Influenza A virus subtypes, bear the capability to yield to a pandemic owing to their potency to yield illness and exemplify efficient human-to-human transmission, especially where little, or no previously existing immunity highlighted among human (Ison 2010, p.812). The study indicated significant differences in incidence among age groups whereby the incidences peaked in school-age children. Moreover, the study demonstrated that proximity to airports and intersection by national highways or freeways, rather than railways, detailed variables linked with the presence of a disease within a country. The findings demonstrate that interventions focussed on domestic travel, climatic factors, and population density could play a central role in mitigating the public health impact linked to future influenza pandemics (Li-Qun, et al. 2012, p.890). Significance of public health issues in the Case Numerous countries have recently reported data on the linkage between severe H1N1 influenza and a collection of underpinning risk factors, but such data presented in diverse formats, deriving direct comparisons across countries is difficult, with no consensus for some conditions (Dawood, et al. 2009, p.2605). The study pursued to characterize the temporal and spatial distribution of pandemic influenza within mainland China, besides comprehending the diffusion pattern of the disease within China, as well as risk factors for local transmission and invasion of H1N1 (Li-Qun, et al. 2012, p.890). The analysis of the information gathered together with unearthing underpinning risk factors avails an opportunity to highlight epidemic characteristics and transmission patterns within China, which, in turn, avail useful information for prevention and control measure in future epidemics. The Rationale for an Epidemiological Study Epidemiology delineates a philosophical approach of probing a health problem, and can be employed to a broad range of problems right from the transmission of an infection disease agent to the design of a fresh strategy of health-care delivery. Cross-sectional studies examine the relationship between disease and accompanying variables of interest as they manifest in a defined population as a sole point in time (Bonita, Beaglehole and Kjellstro?m 2006, p.44). The case study employs analytical cross-sectional study as it investigates the association between putative risk factors for invasion and local transmission of the disease. Cross-sectional studies attempt to examine and compare estimates of disease prevalence between diverse populations and subsets of populations at a certain period. This approach can be considered as surveys that take place over limited periods concerned with detecting disease, estimating its prevalence in diverse populations, or diverse groups within populations, and investigating the impact of the presence of diverse determinants on disease prevalence (Carneiro and Howard 2011, p.93). Cross-sectional studies are comparatively quick and easy to conduct as they do not necessitate long-periods of follow-up (Hennekens and Buring 1987, p.7). Moreover, the data on all variables is collected only once to assess the prevalence of all factors of interest. Cross-sectional studies allow multiple outcomes to be studied. Furthermore, cross-sectional studies allow effective, descriptive analyses and generation of hypotheses. This study can be regarded as limited based on its capability to draw valid conclusions as to the connection between a risk factor and health outcome. Cross-sectional studies mainly measure prevalent instead of incident cases; hence, the data essentially mirror determinants of survival as aetiology (Aschengrau and Seage 2008, p.158). The approach may also be unsuitable for studying rare diseases or disease manifesting short duration. The established associations may also be difficult to interpret. # 2 a) What is influenza A (H1N1) virus The label “swine flu” originally employed to describe this form of influenza since laboratory tests indicated that this strain of flu virus comprised of genes that were analogous to the ones that caused influenza among pigs. H1N1 can be regarded as bearing most dangers compared to other flu based on the fact that it has type A virus that can yield to an enormous number of morbidity and mortality (CDC, 2009). Influenza type-A viruses remain mainly divided into categories (low pathogenic and highly pathogenic) that entail their capability to render severe disease grounded in molecular characteristics of the virus and mortality within birds under experimental conditions (Stephen, Ninghui, Yeh and Zhang 2011, p.334). b) What is the population? The case study employed a database that detailed all cases of pandemic influenza (H1N1-2009) registered to the China Information System for Disease Control and Prevention (CISDCP) from May 9, 2009, when the initial confirmed case in China reported up to December 31, 2009. A laboratory-confirmed case delineated in line with World Health Organization criteria details that an individual with influenza-like symptoms, and laboratory-confirmed pandemic influenza A virus infection based on a number of tests such as viral culture (Jamieson et al., 2009, p.451). All the laboratory cases registered in 2009 were included in the analysis, inclusive of information regarding age, sex, residence address, occupation, work address, hospital admission data and address, onset data and location, and clinical outcome (Cordova-Villalobos, et al., 2009, p.21). c) The Cause-Aetiology H1N1 flu virus can be regarded as the most dominant subtype/strain of influenza being H1N1 that also cause infection in humans. Influenza viruses constantly mutate, and when a swine flu virus manifested in humans it is perceived to have “jumped the species barrier,” or mutates in a manner that enables it to cause the condition in humans (Taubenberger, Reid and Fanning 2000, p.241). Symptoms of swine flu among humans are analogous to most influenza infections: fever (100F or higher), nasal secretions, cough, headache, and fatigue (Garten, et al. 2009, p.197). Patient can get pneumonia in the event that the viral infection persists and some patients may develop seizures. d) How influenza A (H1N1) virus spreads/risk factors within the population and the environment The swine flu virus is highly contagious and spreads in the same manner as ordinary cold and flu. A flu virus comprises of tiny particles that can be spread via droplets that emanate from the nose and mouth in instances when a person sneezes or coughs. Swine flu remains mainly transmitted form one person to another through inhalation or ingestion of droplets containing virus from infected persons sneezing or coughing. Closed mode of transportation can be regarded a risk factor since transmission rates of influenza can be enhanced by close and frequent contact. e) How to control influenza A (H1N1) virus In the case of H1N1 virus, the most effective way to eliminate the infectious disease entails isolation, quarantine, and prophylaxis, as well as the utilization of gadget methods. Controlling transmission of the influenza may entail the use of quarantine and isolation of persons suspected of infection. Controlling the environment may necessitate the employment of education, giving assistance to vulnerable groups such as through agricultural advice, enhancement of communications, especially while seeking medical within health facilities. f) How to prevent influenza A (H1N1) virus Treatment and prevention of influenza entails multiple infection control mechanisms, inclusive of vaccination, antiviral medications, and management of influenza complications. The first vaccine for H1N1 released in October 2009 detailed a nasal spray vaccine authorized for use in healthy individuals aged between 2 and 49 years. Flu vaccines cause antibodies to develop within the body approximately two weeks after vaccination (Schotsaert, De Filette, Fiers, and Saelens 2009, p.499; Lange, et al., 2009, p.2119). The antibodies avail protection against infection with the viruses that are present within the vaccine (Brown and Kelso 2009, p.300). g) Future Health Care Needs for Mitigating Influenza A (H1N1) virus Several imponderables persist regarding the future trajectory of the H1N1 pandemic. It remains a question whether the novel virus will replace the endemic influenza A virus subtypes H2N2 and H1N1. The virus will then probably behave in a parallel manner as other influenza viruses and undergo customary antigenic drift. Seasonal influenza carries significant disease burden for the elderly and the efficacy of the presently available influenza vaccines within this group remain far from ideal (Webster, Bean, Gorman, Chambers and Kawaoka 1992, p.152). This necessitates institution of novel strategies directed at enhancing vaccine efficacy for the target group. h) Effectiveness Methods for Influenza A (H1N1) Virus The unpredictable nature of pandemics necessitates that the monitoring, and preparedness to immunize against a collection of potential pandemic candidates with the full knowledge that predicting the vagaries of influenza virus behaviour is nearly impossible as demonstrated by the unexpected emergence of H1N1 (CDC 2009, P.749). The study concludes that interventions directed at domestic travel, population density and climatic factors can play a critical role in mitigating the public health impact of future influenza pandemics (Smith, et al. 2009, p.1122). An effective infection control program for pandemics influenza employs parallel strategies implemented for any infectious agent inclusive of the facility and environmental controls (such as engineering controls), safe work practices, standard operating procedures, and personal protective clothing and equipment (Perez-Padilla, et al., 2009, p.680). # 3 a) How do the policies, politics, international agencies (if applicable) and health systems provide the context for the epidemiological study Influenza pandemic manifests when a novel influenza virus materializes that can infect, and can be efficiently transmitted among individuals owing to the absence of pre-existing immunity within the population. The present WHO global influenza preparedness aimed at assisting its members, as well as those responsible for public health. Most plans are mainly divided into a number of phases: interpandemic period detailing period in which there are no new influenza virus subtypes (Costa, Silva, Tavares and Nienhaus 2012, p.747). The overarching public health objectives in this phase entail reinforcing influenza pandemic preparedness at the global, regional, and national level, as well as minimizing the risk of transmission to humans, detecting and reporting such transmissions speedily if it occurs. The core objective centres on maximizing efforts to contain, or impede the spread such as developing a vaccine so as to forestall a pandemic, and gain time to implement pandemic response. The overriding public health objective in pandemic phase entails minimizing the impact of the pandemic. The ubiquitous nature of an influenza pandemic obliges state and local authorities, communities, families, and individuals to learn about organize, and pool resources directed at slowing, responding to alleviating and recovering from a probable pandemic (Kerkhove, et al., 2011). The strategic objectives centres on safeguarding persons against the negative health consequences; organize proportionately in relation to the risk; reinforce international efforts directed at safeguarding and detecting its emergence; reduce the potential health, economic, and social impact; organize and adapt the health and social care systems to avail treatment and support for vulnerable populations to the influenza and its complications (Webber 2005, p.4). Attaining the outlined strategies requires the institution, maintenance, testing, and where necessary implementation of operational response arrangement directed at: responding prompting to changes in alert levels; implementing the program in a flexible, phased, sustainable and proportionate way; and facilitating the earliest possible return to normality (Reka, 2007). The legal Framework The World Health Organization (WHO) incorporated new International Health Regulations (IHR) in 2005. These regulations place a duty on states that all stakeholders to the IHR to inform WHO of any event, regardless of the cause, occurring within their territory that may comprise a public health emergency of international concern (Halder, Kelso and Milne, 2011). Annex 2 of the IHR intended to assist states in deciding whether to inform WHO of an event and makes it apparent of a “human influenza generated by a novel subtype ought to be notified (WHO 2009, p.185). The objective centres on creating a framework within which WHO and others can dynamically assist states in responding to international public health risks by openly linking the regulations to alert and response activities (Fang, et al. 2012, p.890). World Health Organization Regulation (10969-1974-192) demands that it be notified for any violence effect communicable disease that is a threat to humans, which includes influenza (irrespective of its nature or sort). In times of crisis, animal regulations, which comprises of vaccination within a certain time, may be implemented, especially where there is a history of pathogen (Stephen et al. 2009, p.124). Health policies ought to be inspired and propelled by health priorities and should incorporate the wide health policy requirements, inclusive of the needs of certain health systems (Koivusalo 2010, p.396). The sheer nature of pandemic influenza necessitates implementation of international protocols for speedy serum sample collection, preparation and transport to labs amid influenza outbreaks. This may also entail putting outbreak response teams on standby for immediate deployment (Laurie et al 2011, p.211). # 4 a) What are the key findings from the paper? The study avails a comprehensive overview of the spatial and temporal characteristics of the pandemic influenza (H1N1-2009) epidemic within mainland China. The analysis of the invasion of pandemic influenza demonstrated that domestic travel by air plus by national highways and freeways and population density significantly contributed to the spread of the epidemic (Li-Qun, et al. 2012, p.891). Lower temperatures, as well as lower relative humidity, can be cited as the climatic factors that fostered local transmission subsequent to the correction for the impacts of school summer vacation and public holiday, as well as population density and density for the medical facilities (CDC 2009, p.521). b) What are the results? The introduction of a holiday period yielded a reduction in the number of persons diagnosed with the pandemic influenza. The study also showed that the direction of the spread of pandemic influenza recorded from the southeast to the northwest, indicative of the way in which the virus benefited from entering the country via international airports and along the long-distance domestic travel (Bogich, et al., 2012). Evidently, the proximity to airports coupled with the presence of high densities of transportation routes correspond with higher populations density and medical facilities; nevertheless, after correction of these factors, proximity to airports and the presence of national highways or freeways remained strongly linked to the spread of the infection (Potter 1998, p.3). The study confirmed that air travel and transportation routes hastened the spread of pandemic influenza between countries within mainland China. The study suggests that absolute humidity could play a critical role within the transmission of pandemic influenza and seasonal variations in influenza epidemics within temperate regions (Li-Qun, et al. 2012, p.890). c) What the results mean? The study demonstrated that Air travel and travel by national freeways played a critical role in propelling the pandemic. Since transportation by highways remains a critical mode of travel between Chinese cities, its potential holds promise to mitigating any future emerging airborne infections. The findings signify that interventions centred on domestic travel, climatic factors, and population density could play a critical role in alleviating the public health impact of future influenza pandemics (Peiris, Wen-Wei and Hui-ling 2009, p.2954). d) Whether the results valid? The results unearthed by the study are indeed valid. The results are valid given that they highlight aspects that impact on the manner in which individuals mobilize and leverage resources and reflect capacity to highlight, control, and respond to pandemic influenza. e) Capability of the results helps to change practice Public health mitigation measures may entail aspects such as isolation of influenza patients, closure of schools, cancellation of mass gatherings, restrictions on travel, and wearing of masks within the public may conflict with individual freedoms. Devoid of a vaccine, much of public health initiatives cannot adequately contain a pandemic; nevertheless, public health measures can aid to delay the introduction and minimize the spread of pandemic influenza virus within a community (Smith 2001, p.1146). # 5 a) What are the strengths and what are the limitations of epidemiology in this case study? The epidemiological investigation has provided strong evidence linking exposure to the incidence of infection or disease within a population. This study has described the patterns or trend of the pandemic influenza within mainland China and can be utilized to explore possible associations between exposures and the disease (Peiris, Poon and Guan 2009, p.169). The results detailed in the epidemiological study, regardless of whether they highlight an association or not, frequently influenced by the limitations inherent in the study design, or analysis (Woodward 1999, p.5). The results may be impacted on by errors or unidentified bias within the data, the influence of other relevant factors apart from quarantine/isolation, population density, air and domestic travel, and climatic factors or by chance variation (Doherty and Kelso 2008, p.3273). One of the weaknesses of the epidemiology details that health is complicated and controlled by numerous factors; besides, the data analysis, may lack enough flexibility to support the conclusions. Other weaknesses to the epidemiology study stem from the fact that, data on exposure an outcome draws from secondary sources that have been collected by CISDCP probably for different purposes (Abramson 2010, p.98). Hence, the data may not be ideal for testing a certain hypothesis, besides the utilization of summary measures for exposure and the outcome may yield to imprecise or unstable associations, especially where a high degree of variability manifests between the units examined (Vincent, Ma, Lager, Janke and Richt 2008, p.127). b) Applications of epidemiology in relation to the case study The results derived from the epidemiology case study can be regarded as useful and can guide public policy on pandemic influenza and can guide informative experiments. The study can be regarded as having satisfied the five main criteria for establishing a likely association, namely: the strength of association (the relationship between risk factors and pandemic influenza is clear); consistency; temporality (exposure must precede the disease); biological gradient (dose-response relationship); and, plausibility. Epidemiology in the case study has played a critical role in spotlighting and quantifying the risk factors to of pandemic influenza, and mitigating the public health impact of future influenza pandemics. Through epidemiology, the study has revealed a significant deal about pandemic influenza (H1N1) incidence within mainland China and the risk factors to the pandemic. Such studies are essential for health risk assessments; nevertheless, they ought to be interpreted with caution. Reference List Abramson, J. (2010). Inside the 2009 influenza pandemic, New Jersey, World Scientific. Pp.98 Aschengrau, A., & Seage, G. R. (2008). 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