Epidemiology: Influenza

This document provides information on the epidemiology of influenza, including its symptoms, transmission, prevention, and impact on different populations. It discusses the role of social determinants of health in influenza transmission and the importance of vaccination and antiviral drugs for prevention and control. The document also highlights the responsibilities of health departments and community health nurses in preventing and controlling influenza.

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

1
EPIDEMIOLOGY
Answer: 1
Influenza (Flu) leads to mild to severe illness and if not treated on time might lead to
death. Flu is different from a cold and comes suddenly. Common complications associated
with flue include ear infections, bacterial pneumonia, sinus infections and other worsening
chronic conditions like congestive heart failure, diabetes and asthma. Some of the common
symptoms of flue include fever (however, not everyone who have flue suffers from fever),
coughing, sore throat, body aches, runny or stuffy nose, chills, headache, fatigue and at times
lead to vomiting and diarrhea (Centers of Disease Control Prevention [CDC], 2019). This
contagious respiratory illness is a viral disease and is caused by influenza virus that infects
the throat, nose and pulmonary organs. The spread of flu virus mainly occurs by tiny droplets,
excreted by a flu-infected person by means of sneeze, cough or talk. These water droplets
land on the nose or buccal opening of the nearby person leading to transmission of infection.
In rare cases, a person might develop flu infection via touching the object or surface that is
infected with the influenza virus. This infected or contaminated hand when come in contact
with the nose, mouth or eyes of that person, the viral particles are transmitted inside the body.
The time of onset of the first symptom is two days after the first exposure of the virus
however; this time might vary from person to person ranging from one to four days. Every
healthy individual is equally vulnerable to flu. However, children (younger than 5 years),
pregnant women and the older adults who are over 65 years of age are more vulnerable to
develop chronic viral flu. The previous pre-disposition of asthma, diabetes and heart disease
also increase the chance of developing flu (Centers of Disease Control Prevention [CDC],
2019).
According to Centre of Disease Control and Prevention [CDC] (2019), flu activity is
decreasing nationally however, it still elevated. Influenza A (H1N1) pdm09 viruses are more

2
EPIDEMIOLOGY
predominant during October to mid-February and influenza A (H3N2) is commonly
identified during February. The percentage of the respiratory specimens that have tested
positive for influenza viruses in the clinical laboratories have decreases however, influenza A
(H1N1) is predominant in all the 10 U.S. Department of Health & Human Services (HHS)
regions and this includes Boston, New York City, Washington DC, Atlanta, Chicago, Atlanta,
Dallas, Kanas City, Denver, San Francisco and Seattle.
CDC is not aware of the exact death toll of people occurring due to seasonal flu each
year as states are not required to report individual flue related illness or death among the
people older than 18-year of age. Moreover, influenza is infrequently listed in death
certificates of people who die from flue-related complications (CDC, 2018).
Vaccination with flu vaccine is an important step for the prevention of flue each year.
There are antiviral drugs influenza drugs available for the treatment of flu. Common anti-
viral drugs used for the treatment of flue include zanamivir, oseltamovir, peramivir and
balozavir marboxil (CDC, 2018).
Answer: 2
According to Cordoba and Aiello (2016), influenza leads to increased rate of
absenteeism at work along with increase in the annual medical cost that increases the
economic burden by $12 to $14. Social determinants of health (SDH) have a significant
influence behind the developing of the chronic health conditions and mounting evidences
suggest that SDH strongly influence the development of respiratory infections in the U.S. The
main SDH associated with the prognosis of influenza include income, education, social class,
occupation, sex and ethnicity/race. People who hail from poor ethnic backgrounds or from
the minority class have poor access to the healthcare services and vaccinations. This
disadvantaged population is more vulnerable in getting infected with influence. Eradication

3
EPIDEMIOLOGY
of the institutional barriers towards receiving the vaccination might help to overcome the
situation. The lack of education is also a SDH behind spread of infection of influence. Annual
health benefits of influenza vaccination are well-established. However, the footfall of the
marginalized population in the immunization centers is less due to the gap in knowledge
about the disease progression (Cordoba & Aiello, 2016). The study conducted by Mendez-
Luck et al. (2016) highlighted that the black Americans and the Latinos are less likely to get
vaccinated in comparison to the white Americans due to their negative opinion regarding the
effectiveness and safety of vaccination. However, negative opinion about the vaccinations
and lack of proper access to healthcare services do not fully account for the generation of
health inequality in influenza. The marginalized population or ethical minority groups has
poor financial strength or government insurance coverage leading absenteeism in the
vaccination camps. Quinn et al. (2017) highlighted that 70% of the disadvantaged minority
people who resides in the NYC like the undocumented immigrants, sex workers, substance
users and the homeless are interested in being vaccinated but fail to avail the service due to
lack of insurance coverage. This lack of seasonal vaccination or completion of the booster
dosage of vaccination leads to the widespread infection of influenza.
Answer: 3
Epidemiologic Triangle is a model developed by scientists to study the health-related.
The three corners of the triangle indicated three different aspects of disease transition. The
top-most vertices of the triangle is host (organism harboring the disease: humans) and
baseline vertices of the triangle include agent (the causative agents) and environment
(external factors leading to the disease development) (CDC, 2015). In case of influenza (flu),
the causative agent is RNA virus that belongs to the Orthomyxovirus genus. It is classified
into three different types. A, B and C. Type A (Influenza A [H1N1], A [H3N2]) and type B

4
EPIDEMIOLOGY
virus most commonly cause the illness in humans. Type A virus is further classified into three
different subtypes based on the surface proteins neuraminidase (NA) and haemagglutinin
(HA) (Centre of Disease Control and Prevention, 2019.
(Source: CDC, 2015)
The environmental factors leading to the disease transmission include change in the
temperature and humidity due to change in the climatic conditions that create a favorable
environment by viral incubation. The seasonal influenza is common during the month of
October to May in the Northern Hemisphere and In Southern Hemisphere it is from April to
September (Centre of Disease Control and Prevention, 2019).
Special consideration for the prevention of the flu among the school children include
encouraging students, parents and staffs to get vaccinated with yearly flu vaccines. Seasonal
flu vaccination is recommended for everyone starting from 6-month of age unless they have
certain health-related contradiction to flu vaccine (CDC, 2019). Since influenza is a
contagious disease, the infected child is recommended to abstain from school until complete
recovery in order to prevent cross-infection to other children. Among the general population
and in community dwelling adults recommendation of healthy diet along with maintenance of

5
EPIDEMIOLOGY
hygienic condition is recommended in order to reduce the chances of cross-infection (CDC,
2019).
Answer: 4
According to CDC (2015), the state and local health departments hold the main
responsibilities for the effective prevention and control of influenza. However,
comprehensive prevention of influenza is a difficult task and requires effective collaboration
of general population or community dwelling adults and the healthcare professionals. The
duty of the community dwelling nursing profession are the backbone of effective control and
prevention of influenza. The duty of the community health nurse includes comprehensive
dispersal and administration of the anti-viral drugs for the effective prevention of the
outbreak of seasonal influenza. Apart from medicine administration, the nurses are also
required to report the rate of occurrence of the disease by effective collection of data and
reporting in order to ascertain the dispersal and supply seasonal vaccination kit of influenza.
CDC is of the opinion that when the supply of vaccine is restricted, initiatives should be
undertaken in order to deliver vaccines to the vulnerable persons. The follow-up of
vaccination is important in order to ensure the complete dosage of vaccination is given to the
vulnerable population (CDC, 2019).
Demographic data is important in order to get an overview of the population who is
vulnerable in getting infected with viral infection. This helps in proper planning of
vaccination dispersal when the supply of vaccines are limited (CDC, 2019).
Answer: 5
The national organization that addresses influenza is CDC. The influenza division of
CDC has a strategic planning for the effective prevention of by following few basic steps.

6
EPIDEMIOLOGY
CDC recommends yearly vaccination for seasonal influenza in order to protect against flu
virus. Flu vaccination helps to reduce the chances of unwanted visits to doctor’s clinical and
absenteeism at school and works (CDC, 2016). The vaccination is recommended during the
month of October each year. In neonates or the new-born are vulnerable to get infected with
influenza however, they children below 6-month of age are not physically eligible for
vaccination. Such that, CDC recommends vaccination to the primary care givers for the child
who are below 6-month of age, this helps in the promotion of herd immunity. Other
recommendation given by CDC includes avoidance of contact with sick people. If the person
is sick with symptoms of flu, CDC recommends them to stay at home for 24 hours. CDC also
organizes effective campaigns in order to prevent the spread of influenza. The campaign
mainly covers instructions like washing of hands with antiseptic soap or use of alcohol-based
hand rub in order to prevent the transmission of virus through direct contact. The tissues,
which are which to cover the nose or mouth, are recommended to disperse in trash followed
by simultaneous destruction of the same in order to kill the virus (CDC, 2016).
In the domain of taking anti-viral rugs, CDC recommends to take drug within 2 days
post expression of the primary symptoms of flu in order to effective control of the disease.
Starting the medicine can still be helpful especially of the infected individual has a high-risk
factor for flu (CDC, 2016).
Answer: 6
Severe acute respiratory infections (SARI) including influenza are one of the leading
causes of cardio-pulmonary morbidity and mortality throughout the world. Until recently, the
overall epidemiology of influenza virus was limited to only the resource-rich countries. The
new epidemiological reports characterizing the 2009 H1N1 pandemic suggests that influenza
exerts a significant higher toll over the low-income resource constrained countries where it is

7
EPIDEMIOLOGY
a cause of 5 to 27% of SARI. The countries that records higher rate of occurrence of
influenza include Morocco in North America, Guinea, Mali, Nigeria and Niger in West
Africa, Sub-Saharan Africa, Kenya, India, Bangladesh, Bhutan, Philippines and Mongolia
(Fischer, Bhagwanjee & Sevransky, 2014). The increased burden of influenza in these low-
income countries is multifactorial and results from higher rates of com-morbidities like HIV,
poor access of healthcare, vaccinations and anti-viral therapy and limited access to proper
healthcare infrastructure like oxygen therapy and acute care support. Improved worldwide
epidemiology of influenza is important in order to guide proper allocation of the life saving
resources like antiviral medication, vaccinations along with direct improvements in
healthcare for mitigating the impact of influenza infection among the vulnerable population
(Fischer, Bhagwanjee & Sevransky, 2014).
In India the prevention and the control of influenza is both seasonal and avian
influenza is widely reported. Vaccination is recommended for the protection against the
seasonal influenza. Anti-viral drugs for the control of influenza are given within 48 hours
after the onset of the preliminary symptoms of the disease in order to reduce further
complications and deaths (World Health Organization, 2019). In the United Kingdom, annual
vaccination of influenza is well established. The traditional strategy of vaccines is directed
towards the vulnerable groups like the children, pregnant women and older people (de
Lusignan et al., 2016).
Influenza is epidemic in African and sub-Saharan countries. The epidemic surge of
influenza is reported in Taiwan during the tenure of 2016 to 2017. The main reported strain
includes influenza A (H3N2). In Taiwan a total of 1185 outpatients cases along with 690, 353
cases of inpatients and cluster events were reported to be positive for A (H3N2). The detected
strain of virus are antigenically associated to current strain of vaccine and infection by

8
EPIDEMIOLOGY
different clade H3N2 virus do not correlate with immunization with 2016 to 2017
vaccinations (Yang et al., 2018).

9
EPIDEMIOLOGY
References
Centers of Disease Control Prevention [CDC] (2018). Frequently Asked Questions about
Estimated Flu Burden. Access date: 6th April 2019. Retrieved from:
https://www.cdc.gov/flu/about/burden/faq.htm?CDC_AA_refVal=https%3A%2F
%2Fwww.cdc.gov%2Fflu%2Fabout%2Fdisease%2Fus_flu-
related_deaths.htm#deaths
Centers of Disease Control Prevention [CDC] (2018). What You Should Know About Flu
Antiviral Drugs. Access date: 6th April 2019. Retrieved from:
https://www.cdc.gov/flu/treatment/whatyoushould.htm?CDC_AA_refVal=https%3A
%2F%2Fwww.cdc.gov%2Fflu%2Fantivirals%2Fwhatyoushould.htm
Centers of Disease Control Prevention [CDC] (2019). Key Facts About Influenza (Flu).
Access date: 6th April 2019. Retrieved from: https://www.cdc.gov/flu/keyfacts.htm
Centers of Disease Control Prevention [CDC] (2019). Weekly U.S. Influenza Surveillance
Report . Access date: 6th April 2019. Retrieved from:
https://www.cdc.gov/flu/weekly/index.htm#ILIMap
Centre of Disease Control and Prevention. (2015). Lesson 1 Understanding the
Epidemiologic Triangle through Infectious Disease. Access date: 6th April 2109.
Retrieved from: https://www.cdc.gov/bam/teachers/documents/epi_1_triangle.pdf
Centre of Disease Control and Prevention. (2016). CDC Says “Take 3” Actions to Fight the
Flu. Access date: 6th April 2109. Retrieved from:
https://www.cdc.gov/flu/protect/preventing.htm

10
EPIDEMIOLOGY
Centre of Disease Control and Prevention. (2019). Guidance for School Administrators to
Help Reduce the Spread of Seasonal Influenza in K-12 Schools. Access date: 6th April
2109. Retrieved from: https://www.cdc.gov/flu/school/guidance.htm
Centre of Disease Control and Prevention. (2019). Influenza. Access date: 6th April 2109.
Retrieved from: https://wwwnc.cdc.gov/travel/yellowbook/2018/infectious-diseases-
related-to-travel/influenza
Centre of Disease Control and Prevention. (2019).Manual for the Surveillance of Vaccine-
Preventable Diseases. Access date: 6th April 2109. Retrieved from:
https://www.cdc.gov/vaccines/pubs/surv-manual/chpt06-influenza.html
Cordoba, E., & Aiello, A. E. (2016). Social determinants of influenza illness and outbreaks in
the United States. North Carolina medical journal, 77(5), 341-345.
de Lusignan, S., Correa, A., Ellis, J., & Pebody, R. (2016). Influenza vaccination: in the UK
and across Europe.
Fischer, W. A., II, M. G., Bhagwanjee, S., & Sevransky, J. (2014). Global burden of
influenza: contributions from resource limited and low-income settings. Global
heart, 9(3), 325.
Mendez-Luck, C. A., Walker, K. O., & Luck, J. (2016). Preventive services use among
African American and Latino adult caregivers in South Los Angeles. Medical
care, 54(12), 1098.
Quinn, S. C., Jamison, A., Freimuth, V. S., An, J., Hancock, G. R., & Musa, D. (2017).
Exploring racial influences on flu vaccine attitudes and behavior: Results of a national
survey of White and African American adults. Vaccine, 35(8), 1167-1174.

11
EPIDEMIOLOGY
World Health Organisation India. (2019). Influenza. Access date: 6th April 2109. Retrieved
from: http://www.searo.who.int/india/topics/influenza/en/
Yang, J. R., Hsu, S. Z., Kuo, C. Y., Huang, H. Y., Huang, T. Y., Wang, H. C., & Liu, M. T.
(2018). An epidemic surge of influenza A (H3N2) virus at the end of the 2016–2017
season in Taiwan with an increased viral genetic heterogeneity. Journal of Clinical
Virology, 99, 15-21.