Epidemiology Paper Essay
“Tuberculosis (TB), a multisystem disease with myriad presentations and manifestations, is the most common cause of infectious disease–related mortality worldwide. Although TB rates are decreasing in the United States, the disease is becoming more common in many parts of the world. In addition, the prevalence of drug-resistant TB is increasing worldwide. TB is caused by M tuberculosis, a slow-growing obligate aerobe and a facultative intracellular parasite. The organism grows in parallel groups called cords (as seen in the image below). It retains many stains after discoloration with acid-alcohol, which is the basis of the acid-fast stains used for pathologic identification.
Humans are the only known reservoir for M tuberculosis. The organism is spread primarily as an airborne aerosol from an individual who is in the infectious stage of TB (although transdermal and GI transmission have been reported). Classic clinical features associated with active pulmonary TB are as follows: cough, weight loss/anorexia, fever, night sweats, hemoptysis, chest pain, and fatigue. For initial empiric treatment of TB, patients are started on a 4-drug regimen: isoniazid, rifampin, pyrazinamide, and either ethambutol or streptomycin. Once the TB isolate is known to be fully susceptible, ethambutol (or streptomycin, if it is used as a fourth drug) can be discontinued” (Herchline, 2014).
“Tuberculosis (TB) is one of the world’s deadliest diseases: 1) One third of the world’s population is infected with TB, 2) In 2012, nearly 9 million people around the world became sick with TB disease. There were around 1.3 million TB-related deaths worldwide, 3) TB is a leading killer of people who are HIV infected. A total of 9,582 TB cases (a rate of 3.0 cases per 100,000 persons) were reported in the United States in 2013. Both the number of TB cases reported and the case rate decreased; this represents a 5.4% and 6.1% decline, respectively, compared to 2012” (cdc.gov, 2014).
The Commission on Social Determinants of Health identifies social determinants of health as conditions that make social stratification recognizable in the society. The following are structural determinants of the epidemiology of tuberculosis: fast urbanization and growth of population, global socioeconomic inequalities, and elevated levels of population mobility. The said conditions are the causes of unequal distributions of the key social determinants of TB which are poor housing and environmental conditions, food insecurity and malnutrition, and geographical, cultural and financial barriers to accessing healthcare. As a result, the distribution of population of TB mirrors the social determinants distribution, which, in turn, imposes an effect on the four stages of TB pathogenesis: “exposure to infection, progression to disease, late or inappropriate diagnosis and treatment, and poor treatment adherence and success” (Hargreaves, et al, 2011).
The social determinants mentioned above are key risk factors for TB. As an example, overcrowded homes, workplaces and communities, and poor ventilation increase the risk of non-infected persons getting exposure to TB infection. Other factors that could increase susceptibility to TB infection are malnutrition, hunger, and poverty. In addition, these also affect the severity of the clinical outcome of the disease. “Individuals with TB symptoms such as a persistent cough often face significant social and economic barriers that delay their contact with health systems in which an appropriate diagnosis might be made, including difficulties in transport to health facilities, fear of stigmatization if they seek a TB diagnosis, and lack of social support to seek care when they fall sick” (Hargreaves, et al, 2011).
The epidemiologic triangle is a medical tool that is composed of an agent, host, and an environment. This is utilized to explain how a disease spreads throughout the environment, to define the points of intervention in order to prevent transmission, and to provide guidance to investigations in epidemiology. (McMurray, 2007). “The agent in this study is Mycobacterium tuberculosis, an acid fast aerobic rod that reproduces slowly and is hypersensitive to heat and ultraviolet light. TB primarily affects the respiratory system; however, it can also affect the pericardium, lymph nodes, meninges, kidneys, intestines, bones, joints, and reproductive organs” (The Merck Manual, 2014).
“The transmission of the Mycobacterium tuberculosis is spread from person to person via airborne droplets through actions such as coughing, talking and sneezing. The smaller the droplet, the longer it can stay in the air after the infected person has left the area. This causes an increase in the probability of inhalation by another individual. Passing TB from a family member or co-worker is more likely than a stranger in a store or on the streets”. (Reichler et. al, 2002).
Mycobacterium tuberculosis, the infectious disease agent, is readily transmitted to susceptible humans, the host, through respiratory exposure in communal settings or public gatherings, the environment. Individuals with compromised immune systems, such as cancer, being on corticosteroid therapy, and HIV/AIDS, are at greatest risk for getting TB infection. Healthcare workers are continuously exposed to illnesses at the hospitals and long term care facilities, which puts them at risk for TB. “Early detection and treatment of the actively infected person is the key to prevention of transmission of tuberculosis in the healthcare setting” (Smeltzer et. al, 2004).
Nurses are the backbone of TB control. The public health nurse’s role in TB management not only involves management services required for patient care and treatment, but also includes an array of public health activities to assist in preventing and controlling the spread of disease in the community, which is the ultimate goal of TB nurse management. The first domain of community health nursing is assessment and analytical skills. The nurse must possess the essential background knowledge and skills such as state and local demographic profile, TB epidemiology, modes of TB transmission, testing and diagnosis of TB, BCG vaccination, principles of contact investigation and interviewing skills, etc… Moreover, the “community nurse must use communication skills and nursing knowledge to interview clients for history, risks, and prevalent medical conditions, provide case-finding and clinical services to eligible clients living in shelters, group homes, LTAC’s, and correctional facilities” (tbcontrollers.org, 2012).
Program planning is another domain that a community nurse should be an expert on. He / she must use knowledge of current guidelines and local epidemiology to plan program-wide interventions effectively. The following are program planning tasks for the public health nurse / case manager: implement policy and program improvement, incorporate policy into organizational structures, plans, and programs, develop strategies for continuous quality improvement. Three more domains that a qualified public health nurse must be proficient in are cultural competency, community collaboration, and leadership. “The TB nurse case manager is a qualified nurse who uses knowledge of community resources and stakeholders to foster partnerships within the community” (tbcontrollers.org, 2012).
Collaboration with partners, promotion of public health policy and programs, and providing expert advice to other healthcare providers are examples of core competencies of the said domain. Lastly, the nurse’s communication skills are a big key to managing TB in the community. Mutual goal setting, providing emotional support, and educating the patient are key tasks included in the communication domain. Some specific actions are disseminating TB educational materials in different formats, recognizing and addressing misconceptions about the disease, and using appropriate language and language level while conducting patient education. (tbcontrollers.org, 2012).
A popular nationwide agency that addresses tuberculosis is the National Institute of Allergy and Infectious Diseases. “NIAID funds and conducts biomedical research on TB. NIAID also collaborates with other U.S. government agencies and multilateral organizations worldwide to support public–private partnerships to benefit people who have TB, multidrug-resistant TB (MDR TB), and extensively drug-resistant TB (XDR TB), including people who are co-infected with HIV” (NIH, 2007). NIAID’s contribution to resolving or reducing the impact of this disease is achieved through basic research, drug development and clinical evaluation, vaccine development and clinical testing, improving prevention and treatment for people with TB and HIV/AIDS, training, communications, and partnership (NIH, 2007).
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