Epidemiology of Tuberculosis: Outbreak, Treatment, and Prognosis

This paper provides a detailed perspective on the outbreak, treatment, and prognosis of tuberculosis (TB) in the U.S and worldwide. It discusses the mode of transmission, symptoms, complications, and treatment options for TB. It also highlights the social determinants of health that contribute to the development of TB. The role of community health nurses in TB prevention and control is discussed, along with the initiatives taken by CDC and other organizations to eliminate TB globally. The global impact of TB and the situation in countries like India and UK are also mentioned.

Running head: EPIDEMIOLOGY
Epidemiology
Name of the Student
Name of the University
Author Note

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Tuberculosis (TB) is a bacterial disease caused by Mycobacterium tuberculosis
(Centre of Disease Control and Prevention [CDC], 2019). The following paper aims to
provide a detailed perspective of outbreak, treatment and prognosis of tuberculosis (TB) in
the U.S and worldwide. Having a proper demographic and prognosis knowledge of TB will
help to promote successful elimination of the contagious disease.
Answer 1
Mycobacterium tuberculosis colonizes but not restricted to lungs. The colonization of
bacteria is also highlighted in the kidneys, brain and spine. Not everyone infected with TB
bacteria develops the disease or become sick. As a result there are two phase of the disease,
one is the latent TB infection (LTBI) and another phase is known of TB disease. If not
reported on time, TB can be fatal (CDC, 2019). Mode of transmission: TB bacteria is a air
borne bacteria and thus the disease can be transmitted from one person to another whenever
the bacteria comes in contact to air for example bacteria expelled in air by the infected person
through sneezing, coughing, speaking, singing and spitting. The TB infection also spreads by
touch like coming in contact with contaminated hands (handshake), sharing of meal, touching
the linens of beds or toilet sheets and kissing. When healthy person breaths in TB bacteria
settle in lungs and starts replicating and move through blood streams in order organs (CDC,
2019). Symptoms: The symptoms of TB vary with the point of colonization of the bacteria.
The bacteria mainly grow inside the lungs (pulmonary TB) and leads to the development of
symptoms like cough (that lasts for 3 weeks), chest pain, coughing of blood or sputum. Other
associated symptoms include fatigue, weight loss, lack of appetite, fever, chills and sweating
at night (CDC, 2019). The complications associated with TB increases when there occurs co-
infection among the person suffering from HIV (Human Immuno Deficiency Virus). People
with HIV are immune-compromised and are more likely to become infected with TB and this

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eventually becomes fatal (CDC, 2019). TB is treated by a combination of several drugs for
duration of 6 to 9 months. There are 10 drugs, which are currently approved by U.S Food and
Drug Administration (FDA) in order to treat TB. The first line of the anti-TB agents that are
approved by FDA include: isoniazid (INH), rifampin (RIF), ethambutol (EMB),
pyrazinamide (PZA) (CDC, 2016). In 2017, 9015 cases of TB were reported in U.S showing
a decrease in rate of occurrence by 1.6% from 2016. A total of 11 states along with District of
Columbia and New York City reported the incidence of TB at a rate of 2.8 cases per 100,000
amounting to 528 deaths. There is an increase from 470 deaths as reported in 2015. The
highest rate of occurrence is in California, Texas, Florida and New York. The main victims of
TB as per the race and ethnicity in USA are the Asians and Black or African Americans
(CDC, 2017). TB is a reportable disease from 1951 until present as per the website of CDC.
It is recommended to report the suspected or confirmed cases of TB within 24 hours to the
local health officer or the state health department. For the laboratory professional who is
conducting the confirmatory test is required to report to the local health department of state
health department. The notifications must be associated with date and results of the test
performed along with the name and the date of birth of the person from whom the specimen
is extracted (CDC, 2012).
Answer 2
Social Determinants of Health (SDH) are defined as conditions, under which the
people are born, live, grow, work and age. The circumstances are modulated by the
distribution of power, money and distribution of resources at the local, national and global
levels. SDH are responsible for the generation of health inequalities or avoidable difference
in the health status of the people from different race, ethnicity, culture or countries. The main
social determinants of health includes employment conditions, social exclusion, public health

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accessibility, gender equity, early development of child, globalization, social support,
addiction, food and transportation (World Health Organization [WHO], 2019). According to
WHO (2018), poverty is one of the powerful determinants behind the development of TB.
Poorly ventilated and overcrowded working and living environment is inter-related with
poverty and cast a significant risk behind the transmission of TB bacterium. Malnourishment
is also an important risk behind the development of TB. Poverty or lack of proper financial
support at home is associated with lack of proper maintenance of healthy diet leading to
malnourishment and subsequent development of TB and the main victims of these are
children who are in their early childhood (WHO, 2019). Sester et al. (2014) are of the opinion
that children who are devoid of proper nutrition during their early years of development
become immuno-compromised, making them vulnerable for the bacterial attack and thereby
increasing the tendency of developing TB. Lack of proper employment opportunity is another
important SDH that leads to the development of TB. Unemployed people are more prone
towards getting affected with substance abuse and depression (WHO, 2019). de Colombani
and Hovhannesyan (2015) stated that substance abuse like marijuana, tobacco and alcohol
increases the vulnerability of developing lung TB. Under depressive condition, people are
prone to become addicted to tobacco smoking increasing the vulnerability of TB
development.
Answer 3
Epidemiologic Triangle is defined as a model developed by scientists in order to
study health problems. The three corners of the triangle or the vertices are: (i) agent or the
micro-organism that is responsible for the disease development; (ii) Host or the organism
harboring the causative agent; (iii) environment or the external factors leading of the disease
transmission (CDC, 2015).

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(Source: CDC, 2015)
In case of TB, the agent is Mycobacterium tuberculosis. The host is human.
According to Mycobacterium tuberculosis complex (MTBC) has emerged as human pathogen
from Africa and have colonized in the world through Out-of-Africa migrations of modern
humans. Seasonal variations during the autumn and spring can be regarded as the main
environmental factors behind the spread of pulmonary TB (PTB) (Cambier, Falkow &
Ramakrishnan, 2014). During seasonal variations, there occurs sudden change in temperature,
humidity and sunlight leading to the generation of favorable environment for MBTBC
multiplication. For the community the special notifications include avoidance of the
community health events in poorly ventilated or over-crowded place leading to the
development of PTB from cross-contamination. For the general population the transmission
of TB from one host to another is high in the families with one infected members through
direct touch or through air. Thus, the infected family member is recommended to keep under
isolation. In case of schools, transmissions occurs through air or by tough from one child to
another. Moreover, during cloudy winter or rainy season, there occurs less exposure of sun
and thus minimal conversion of pro-vitamin D3 to pre-vitamin D3 by sunlight. The

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deficiency of Vitamin D increases the vulnerability of developing TB among children
(Álvaro-Meca et al., 2016).
Answer 4
According to CDC (2015), local and state health departments hold the main
responsibility for effective prevention and control of TB. However, a comprehensive
prevention of TB is a complex task and required effective collaboration from a broad range of
individuals of them the community health-nursing professionals hold the premium role.
Nurses are the backbone of TB control and prevention. The main duty of the community
health nurses includes comprehensive procurement of anti-bacterial drugs for eradication of
TB. Anti-bacterial drug therapy is a global strategy that promotes a standardized approach for
effective control of sputum positive TB (CDC, 2015). The implementation of drug therapy
require rigorous follow-up. According to Karanjekar et al. (2014), there are a high percentage
of dropouts from DOTS therapy. The reason behind this, patient might feel unwell, or due to
misconception or lack of proper knowledge about disease prognosis. Effective counseling by
the community health nurse helps to tackle this situation. However, government must support
TB programs by channelizing funds to community health nurses in order to make follow-up
visits to patients possible and thereby reducing the number of defaulters. Apart from DOTS
implementation, other role of the community health nurses include collection data in domain
of newly reported cases of the TB and arrangement of that data based on different
demographic variable like place of occurrence, gender, age, race, ethnicity and employment
status. The collection of data will be followed by data analysis (CDC, 2015).
The demographic data helps in understanding the percentage of TB outbreak per year
along with the percentage of death reports among the reported cases. Demographic data from
each state helps in the generation of the comparative chart that helps in highlighting the

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vulnerable states in the country along with the main ethnic group or age group who are the
prime victims of the disease. These demographic data helps in the bring change in the policy
planning for the TB prevention or setting out patient centered health awareness program and
thereby helping in the comprehensive prevention of the disease (Stewart et al., 2018).
Answer 5
The national organization that addresses TB is CDC. CDC, Division of Tuberculosis
Eliminations (DTBE) has a strategic planning for the elimination of tuberculosis in US and
globally. The strategic focus on two goals, domestic elimination of TB (in Us) and global
reduction of TB by decreasing the global incidence and mortality by 50% in compared to the
base line data of 1990 (CDC, 2012). The global initiative is known as Stop TB Partnership
Global Plan to Stop TB (2006 to 2015). The DTBE priorities include:
(i) Prevention of the new cases of TB; reduction in TB outbreak among the foreign-
born persons who are residing-in or who are travelling to U.S
(ii) Reduction of occurrence of TB among the people who belongs to the racial or
ethnic minority group in U.S by addressing the social determinants of health
(iii) Reduction in the overall impact of the multi-drug and extensively drug resistant
TB both globally and in the U.S
(iv) Reduction in the rate of occurrence of HIV associated TB in the U.S and globally
(CDC, 2012)
Answer 6
Under the global implication of TB, it can be said that TB affects a fourth of world’s
population that constitute 2 billion people. Nearly 1.8 million die per year and thereby

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making TB one of the leading infectious disease killers in the world (CDC, 2018). CDC
(2018)also reports that of 10.4 million people who become infected with TB per year, at least
four million people miss proper treatment or fail to avail treatment and thus creating a barrier
behind successful eradication of the disease. The incomplete adherence of TB therapy leads
to the development of multidrug resistance bacteria making TB unmanageable further.
Furthermore, TB outbreak holds a special concern for people with HIV infection or who are
immune-compromised (CDC, 2018).
In India, TB is control by the effective implementation of DOTS (Directly Observed
Treatment, Short Course) (CDC, 2018). India also have Revised National TB Control
Program (RNTCP) which have helped in saving 7.75 million lives in India (Mandal et al.,
2017). In UK, the treatment of TB is done with the help of antibiotic treatments for 6-month
of duration. In certain cases, treatment might required more than 6-month. The treatment for
multi-drug resistant TB last for 24 months. As per the UK statistics, there are 54 reported
cases of TB in 2015 and majority of the strains are resistant to rifampicin. UK has special TB
Alert toolkit in order to support treatment regimes and strategies for the group of population
who refuse to take treatment for TB Public Health England. (2018).
TB is endemic in India due to drug resistant TB strains and unreported cases of TB.
The country has a largest number of TB reported cases in the world that constitutes over a
quarter of the global TB along with the multidrug resistant TB burden. During 2016, nearly
2.79 million people were affected with TB in India and of them 435,000 died. India also has a
highest number of multidrug resistant TB (MDR-TB) outbreak including rifampicin resistant
strain and amount to 147,000 cases at the end of 2016. Another alarming statistics is more
than 850,000 cases of TB in India either goes undetected or remain untreated or are
diagnosed and treated by private healthcare professionals with substandard drugs leading
increase in the MDR-TB (U.S Agency for International Development [USAID], 2017).

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