Influenza Epidemiology

Influenza Epidemiology

Influenza is a viral condition that is caused by type A or B viruses that usually spread among humans to be responsible for the epidemics of the flu. Influenza A can be divided into various sub-types in consideration f the genes that constitute the surface proteins. The illness is caused by the different types and subtypes of influenza that circulates during the flu season. Individuals having influenza experiences various symptoms which may encompass the following; a sore throat, fever, cough, body or muscle aches, stuffy nose, fatigue, and headaches. Children in certain instances may experience diarrhea as well as vomiting.

Influenza virus can be transmitted to human beings in three ways.  These include through contact with objects that are contaminated by fomites such as doorknobs or toys, by inhalation of aerosols that are loaded with the virus as well as by direct contacts with individuals that are already affected. Influenza Is contagious and can be passed from one passion to another by a healthy individual one day before the symptoms begin to appear, and this may continue 5 to 7 days after being sick. One can also acquire the condition by reassortment events between livestock and humans to pass the virus, especially from swine. Mondiale de la Santé & World Health Organization. (2017) reiterates that the cases can also be attributed to exposure to infected through de-feathering, visiting live bird markets, bird mortality in the neighborhood, consumption of dead or sick poultry and occupational exposure for the poultry farmers.

In addition to the human transmission, livestock human reassortment events are also vital in the transmission and development of the illness (Fox, S. J., Miller & Meyers, 2017). This is common especially when the virus harbors the swine where it can circulate and remain active for years before being passed to humans. This formed the origin of the various pandemic events that have occurred in the past save for 1977 which was caused by a lab escapee and the one of 2009 which originated from a human-derived variant that was acquired via assortment events and believed to have existed for a reasonable period before the transmission.

The management of influenza entails isolation and social distancing with the infected individual to avoid transmission. It is also controlled by prophylaxis as well as treatment with antiretroviral medications. Mondiale de la Santé, O., & World Health Organization. (2017) alludes that with the administration of Oseltamivir from the day of onset to 4 days treatment has a positive outcome for the affected individual. This treatment is beneficial when initiated early enough before the progression of the condition. It’s also crucial for early identification and quick response to curb the transmission. For further management of the condition, the public health agencies establish extensive surveillance network s in live stocks, humans and the wild bird populations.

Influenza is a reportable condition since its occurrence can mark a beginning of an epidemic due to its contagious and nature of transmission. One case of influenza is considered an outbreak and need to be confined and arrested before it spreads to a larger area.  The determination of the condition ought to be reported to the regional disaster preparedness units that would associate with the world health organization and the center for disease control and prevention for the mobilization of the response teams (Wolf, 2017)).

Determinants of health and how they contribute to the development of influenza

Various factors come together to influence the health of individuals and communities. The circumstances and the environment surrounding the individuals are vital in determining whether the population is healthy or not. In most instances, individuals are not able to directly control most of the determinants that impact their lives thus victim blaming fr poor health and crediting for good health may not be appropriate for various individuals. The multiple determinants of health include the following:

Education- low education is associated with less information concerning healthy living, failure to go for medical check-ups as well as prompt intervention in the occurrence of a disease. These aspects links the low education with poor health, lower self-confidence, and more stress.

Physical environment- various contributors to good health within the surrounding include healthy workplace, safe water and clean air, safe roads, houses, and communities. Employment and working conditions are also crucial in supporting the health of individuals in such settings. Dump environment containing fomites within the houses and the working places can contribute to the transmission of influenza virus to other individuals. Infected individuals within the surrounding may also pose a risk to their fellows in passing the disease. Fox, S. J., Miller & Meyers, (2017) alludes that influenza is associated with summer and spring which increases its pandemic severity as well as the chances of transmission to various individuals. Besides, the social-environmental factors such as humidity and school calendar are perceived to favor transmission of the condition hence determines the health of population affected.

Genetics- the passing of genes from one generation to the next is vital in the determination of the lifespan of individuals, the likelihood of developing illnesses and healthiness of the siblings. According to the study by Fox, S. J., Miller & Meyers, (2017), there exists a heterosubtypic immunity stemming that occurs from early childhood following occurrences of infections of the novel H7N9 and H5N1 as was in the case of China.

Health services- the access and use of the healthcare services determine the move by the concerned parties in preventing and managing conditions which influence health. For the case of influenza, the early one seeks treatment the better for prevention of the progression of the disease as well as its spread to other individuals.  Seeking treatment within two days of infection is critical in its management. This translates to severity and even fatality of the condition if the person infected with influenza does not seek treatment or is not able to access the healthcare services.

Gender- due to the body composition as well as the hormonal differences, men and women experience various health conditions at different ages. According to Mondiale de la Santé, & World Health Organization (20170 the overall male to female ration of individuals that suffer from influenza favors the females with the numbers depending on the age. For individuals younger than ten years old, the ratio is 1 to 0.9.

Social support networks- substantial support from external forces such as the family, friends, community, support groups as well as organizations are associated with better health. The culture and beliefs of the family and the community also affect the health of individuals accustomed to them since they have an association with the use of healthcare services.

The Epidemiologic Triangle as it relates to Influenza

Epidemiologic triangle refers to a scientific model that illustrates the disease causation within a setting. The triangle has three vertices representing three aspects namely: agent, host and the environment. The three aspects constitute the moves that are involved for an illness to occur in an individual.

The agent is the cause of the disease. This is the disease-causing organism of which in this case is the influenza type A and B viruses which infects the upper respiratory system to cause illness. The hosts refer to the organisms which in most cases are animals and humans that are exposed to the diseases causing organisms and even harbors them. The host can be an organism that can get sick as well as the carriers that spread the disease. For influence, the hosts are human beings that are affected disease and can also spread it during the window period of the infection.  The illness is also harbored by livestock which passes it to human beings during reassortment events. The hosts may react differently to the agents causing the condition.  For instance, Fox, S. J., Miller & Meyers, (2017) alludes that children develop immunity following infection by the novel H7N9 and H5N1 compared to the adults. At the same time, children are likely to present with symptoms of diarrhea and vomiting compared to the adults.

The third aspect of the epidemiological triangle is the environment. It refers to the favorable surroundings and circumstances that are external to the host and allows transmission of the disease. The influenza virus survives in the humid seasons and during the school calendar. It services in the body fluids and can be passed via droplets that the infected individuals pass through coughs and sneezes.

The Role of the Community Health Nurse

The community health nurse is vital in the surveillance of the condition together with the public health agencies. These activities entail teaching of the public on the prevention strategies for the condition as well as signs and symptoms to look out from individuals with the aim of early identification of the condition(Edmonson et al., 2017). In the case finding, the community health nurses are essential in the evaluation of the symptoms of patients and preventing others from contracting the condition. He or she does this by ensuring his or safety by being on protective gear and allowing laboratory investigations towards the diagnosis of the condition.

The community health nurse also acts as the communication agent between the facility or point of case finding and disaster preparedness unit for further investigation. In conjunction with the disaster preparedness team, the nurse assists in the determination of the movements of the patients and the place of residence in identifying probable individuals that are affected. In the process, he also communicates to the community or the region affected by the situation at hand and teaching them on the vigilance that they need to undertake for the determination of all the affected individuals.

The data obtained is analyzed from identified cases. Treatment of the individuals is facilitated, and when stable, they are discharged under the follow-up of the community health nurse. The nurse also forms the part of the team that prepares the report of the occurrence, determination, management, and plans for a similar incidence.

National Agencies or Organizations that Address Influenza

World Health Organization – it is supported by various partners in managing health risks around the globe. It developed the Tool for Influenza Pandemic Risk Assessment that is key in the characterization of the risks related to human to human transmission of zoonotic conditions. This move assists in the determination fo risks of influenza and curbs the occurrences of the condition by applying various preventive measures. Also, WHO have established the criteria to assess for pandemics and the measures that coordinate the response teams in the case of such events.

Global Immunization Division- in association with the Center for disease control and prevention, this agency has assisted in the development and distribution of vaccines against the strains of the influenza virus.  It forms the primary influenza vaccine manufacturer for several countries having laboratories and licensing agencies in various countries to meet its missions.

Centers for Disease Control and Prevention – It is also a principal agency in the protection of public health and safety through the control the health risks to the public. In the management of influenza, the center for disease control and prevention has been on the forefront in the isolation of viral constraints of influenza as well as confining outbreaks in the event of epidemics.  Through this moves, they have assisted in the prevention of transmission of the condition to various vulnerable individuals.

The Global Implication of Influenza

According to Mondiale de la Santé & World Health Organization (2017), 859 human cases of the H5N1 infections have been reported. These case were from 16 countries. Most of the cases occurred in Egypt, with others reported from China, Indonesia, and Bangladesh. These have reduced with the recent reports in 2016 and 2017 coming from Egypt alone. The genetic clades that were identified in China and Bangladesh were isolated and characterized to prompt the determination of the new candidate influenza vaccines viruses in 2016 in China, Middle East, and Africa. In China, the agricultural sectors opted for nation-wide immunization program that would control the condition in the poultry sectors as it forms the leading source of human transmission. This vaccination was to be made against the H7N9 virus for months to reduce the co-circulation of the viruses and curb zoonotic transmission dynamics.

In other areas such as the cities of London and Frankfurt, influenza preparedness is enacted to keep a check and get ready to encounter the condition. Besides, the global preparedness for the condition has turned to be a global enterprise due to the universal vulnerability in various parts of the globe. According to Wolf, (2017), the various outbreak management teams have changed from containment measures at the entry points in countries such as airport and moving towards a quick response to the source of the outbreak to contain it at that point.

Influenza is a pandemic condition that can emerge abruptly to affect the entire globe. According to Fox, S. J., Miller & Meyers, (2017), this may an exception based on the historical pandemics which have occurred in the Northern Hemisphere immediately after the flu season. They occurred in March 1918, April 1957 and 2009, May 1889 and 1977 and July 1968. The seasonal flu provides a heterosubtypic immunity. The northern hemisphere is characterized by the presence of many livestock in comparison to the southern hemisphere hence translates to the relationship that predisposed it to the previous pandemics. It also makes it more vulnerable to subsequent pandemic events.

Other areas such as China are dependent on the transient heterosubtypic immunity that comes about after the seasonal flu infection. It forms one of the many forms of the immunological heterogeneity that can curb emergence of pandemic events. The age-specific occurrences of severe and deadly infection by the novel H7N9 and H5N1 indicated a long-lasting immunity that children in the entire nation experienced against the influenza infection.




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