Assigment .Apa seven . All instructions attached.
butterflyl
Marta.docxMarta Garcia Diaz
5/31/23, 6:10 PM
Top of Form
Discussion 4: Marta Garcia
TB Surveillance
Since 1953, in cooperation with state and local health departments, the Centers for Disease Control and Prevention (CDC) has collected information on each newly reported case of tuberculosis (TB) disease in the United States. Currently, each TB case report (Report of Verified Case of Tuberculosis or RVCT) is submitted electronically to the CDC’s Division of Tuberculosis Elimination. Figure 1 depicts reported TB cases in the United States from 1982 to 2005.
Figure 1. Reported TB Cases
Question 1
What factors might have contributed to the increase in TB cases from the mid-1980s to 1992? (See figure1 above.)
The increase in TB cases was due to the HIV/AIDs epidemic. HIV virus lowers the body's immunity and increases the risk of contracting AIDs and other opportunistic infections. Another reason for the increase in TB cases is the lack of proper attention to public health measures for curbing TB (CDC, 2008). This is possible due to lower levels of TB reported in previous years. It is possible that the health sector let its guard down in the fight against TB
Table 1 below presents the distribution of new cases of tuberculosis by age group and sex. Use this information to answer the next question.
Table 1. Number of TB Cases Reported to CDC by Age Group and Sex for 2007
|
Age |
Sex |
No. TB Cases |
|
< 15 |
M |
388 |
|
< 15 |
F |
391 |
|
15-24 |
M |
915 |
|
15-24 |
F |
666 |
|
25-44 |
M |
2557 |
|
25-44 |
F |
1759 |
|
45-64 |
M |
2747 |
|
45-64 |
F |
1294 |
|
≥ 65 |
M |
1502 |
|
≥ 65 |
F |
1076 |
Source: Table 15. Tuberculosis Cases by Hispanic Ethnicity and Non-Hispanic Race, Sex, and Age Group: United States, 2007
Question 2
1. In 2007, which group had the greatest number of TB cases?
From the table, males aged 45-64 years had the highest cases of TB.
B. Does this mean that males 44-65 years of age are at greatest risk for developing TB?
This may not be an indicator of males 44-65 years being at risk of TB infection. To conclude on which group is at risk, the total number of people in each age group should be indicated and prevalence or incidence rates calculated to determine which group is at risk.
Estimating the Risk of Developing TB Disease
The number of TB cases per 100,000 population, called the TB case rate, is determined by the following equation:
number of new TB cases that occur during a specified time period x 100,000 the population at risk
Also called cumulative incidence or an incidence rate, this formula provides an estimate of the risk for developing a disease. The population at-risk information for the United States, which is needed to calculate the TB incidence (or case) rate, is collected by the US Census. Information on the US population by year can be found on the United States Census Bureau’s American Factfinder website ( http://factfinder.census.gov/home/saff/main.html?_lang=en ).
Question 3
1. Estimated* population values of the number of new TB cases reported to the CDC appear in Table 2 below. Use this data to calculate the TB (incidence rates) case rates for the years 2000 to 2007.
Table 2. TB Case Rates: 2000-2007
|
Year |
New Cases |
US Population Estimates |
Case rate per 100,000 (incidence rate) |
|
2000 |
16309 |
281,189,655 |
5.8 |
|
2001 |
15946 |
284,750,000 |
5.6 |
|
2002 |
15056 |
289,538,462 |
5.2 |
|
2003 |
14837 |
290,921,569 |
5.1 |
|
2004 |
14501 |
295,938,776 |
4.9 |
|
2005 |
14065 |
293,020,833 |
4.8 |
|
2006 |
13754 |
299,000,000 |
4.6 |
|
2007 |
13299 |
302,250,000 |
4.4 |
* Estimated population values for this exercise were generated using the rates and cases that appear in the 2007 Surveillance Report (reference 2).
1. Describe the trend in TB incidence rates over time.
The incidence rate of TB has been slowly declining between 2000 to 2007 from 5.8 per 100,000 to 4.4 per 100,000.
Question 4
Use the CDC data and Table 3 below to calculate the age-specific incidence rates of TB for 2007. EXAMPLE: 2007 <15 yr. old males = 245/10,652,174X 100,000= 2.3
Table 3. Case Rates: 2007
|
Age |
Sex |
Cases |
Estimated Population by Sex and Age Group |
Incidence Rate per 100,000 |
|
<5 |
F |
245 |
10,652,174 |
2.3 |
|
<5 |
F |
221 |
10,045,455 |
2.2 |
|
5-14 |
M |
143 |
20,428,571 |
0.7 |
|
5-14 |
F |
170 |
18,888,889 |
0.9 |
|
15-24 |
M |
915 |
21,785,714 |
4.2 |
|
15-24 |
F |
666 |
20,812,500 |
3.2 |
|
25-44 |
M |
2557 |
42,616,667 |
6.0 |
|
25-44 |
F |
1759 |
41,880,952 |
4.2 |
|
45-64 |
M |
2747 |
37,121,622 |
7.4 |
|
45-64 |
F |
1294 |
39,212,121 |
3.3 |
|
≥65 |
M |
1502 |
15,978,723 |
9.4 |
|
≥65 |
F |
1076 |
21,959,184 |
4.9 |
Question 5
1. Which group has the highest incidence rate of TB in 2007?
The incidence rate is highest in males aged 65 years and above at 9.4 per 100,000.
1. Why do you think this age group has the highest TB case (incidence) rate of TB?
A possible reason for the high incidence rate of TB in this group is that they are highly immunocompromised. The immune system declines with age. It could also be that the elderly had been infected with TB at young age weakening the immune system and have been re-infected.
1. Is your answer for question 5a different from your answer for question 2a? If so, justify why your answer is different.
Yes, they are different. In part 2a, the total population at risk is not given. In part 5b, the population at risk is given and the incidence rate has been calculated.
TB Incidence Rates and Mortality Rates
Look at Table 4 on the next page of this exercise. This table presents information on TB morbidity (or illness) by providing the number of cases and the case (incidence) rates. It also presents information on mortality (or death) associated with TB in the US by providing the number of deaths and the death rates from 1953 to 2006.
Question 6
Describe the change in TB case (incidence) rates presented in Table 4 below.
Since 1953, incidence rates of TB have been on the decline overall. However, there was an increase in incidence rates reported in the late 1980s and the early 1990s. The reason for the increase was due to the AIDs pandemic reported at the time. From 1993, TB cases began to decline
Tuberculosis Cases, Case Rates per 100,000 Population, Deaths, and Death Rates per 100,000 Population, and Percent Change: United States, 1953–20072Source: CDC. Reported Tuberculosis in the United States, 2007. Atlanta, GA: U.S. Department of Health and Human Services, CDC, September 2008. Table 1, page 1.
Question 7
Table 4 includes the cause-specific death rates associated with TB.
Definition: number of deaths associated with TB each year x 100,000
Mid-period population
The rates for 1977, 1978, and 1979 are repeated below.
|
Year |
Cause-Specific Death Rate for TB |
|
1977 |
1.4 per 100,000 |
|
1978 |
1.3 per 100,000 |
|
1979 |
0.9 per 100,000 |
What is the TB mortality rate percent change between 1977 and 1978? Remember: Percent change formula: Time2-Time1 x 100
Time 1
1.3- 1.4 X100 = -7.1%. TB death rates decreased by about 7%.
1.4
Question 8
What is the TB death rate percent change between 1978 and 1979?
0.9-1.3 X 100 = -30.8%. TB death rates decreased by about 31%.
1.3
Question 9
What are the possible reasons there was such a large difference between the rates for these years?
Some of the reasons could be changes in population size and developments in the treatment of diseases. Another possible explanation could be changes in the way a disease is classified. For example and from the table, footnote number 2 clarifies that “The large decrease in death rate in 1979 occurred because late effects of tuberculosis (e.g., bronchiectasis or fibrosis) and pleurisy with effusion (without mention of cause) are no longer included in tuberculosis deaths.” Therefore, some deaths classified as caused by TB in previous years were no longer used in defining TB deaths” (CDC, 2007).
TB Morbidity (Incidence Rates vs. Prevalence Ratios)
Tuberculosis is a disease where people can become infected and remain infected without symptoms for many years. TB infection (without active disease) is called latent TB infection. The identification and treatment of people with latent TB infection is an important goal of TB control because successful treatment of TB infection will prevent the progression from infection to active disease. TB infection can be detected using a skin test and more recently through a blood test.
An epidemiologic measure that can be used to measure the proportion of a population with a specific infection or disease is called the prevalence ratio. For example, conducting tuberculin skin testing in a homeless shelter would provide a measure of the proportion of residents who have been infected with TB. This would include both old and new infections.
The following formula can be used to determine the prevalence ratio:
number of new and old TB infections during a specified time period x 100,000 total (usually mid-period population) during the same time period
Note: incidence rates and prevalence ratios may be expressed per 100 or per 1,000. They are commonly presented per 100,000.
Question 10
Suppose that a county TB controller would like to know how many people currently living in a local nursing home are infected with TB. After receiving the appropriate approval and consent from the nursing home residents and administration, she has a trained nurse administer and read the results of tuberculin skin tests. Of the 100 nursing home residents who were tested, 30 had positive tuberculin skin test results during July of that year.
What is the prevalence ratio of TB infection in this nursing home during the month of July? Provide your answer per 100.
The prevalence rate would be 30% in the month of July. It is evident that 30% of the residents in the nursing home were exposed to TB at some time in their lives. Some of the cases could be newly infected while others would be old cases of TB infections.
Question #11
In this particular nursing home, all 100 residents remained in this nursing home for the next year at which time only those who did not have an initial positive tuberculin skin test result were tested again. Among these 70 residents who were tested again, 5 had a positive tuberculin skin test result.
What is the incidence rate of TB infection in this nursing home during the next year?
The incidence rate of TB would be 7% (5/70). This is because all the 70 residents tested had a negative tuberculin skin test before July of the previous year. Therefore, the 5 residents infected with TB are all new cases.
Question #12
You have been asked to describe the science of epidemiology to a new group of nursing students. Covering the web of causation, morbidity, and mortality, how would you explain this to the students?
The web of causation describes how predisposing factors interact with each other to cause disease. There is a combination of factors within and outside the body of the individual that leads to disease progression, for example, genetics, age, gender, and environmental factors leading to TB. Morbidity is the state of having a certain disease condition or health event. It is inclusive of all people affected by the disease. Mortality on the other hand refers to the number of deaths in a specified population. It is expressed per 100, 000 people in a year (Hernandez & Kim, 2019).
References
CDC., (2008). Reported Tuberculosis in the United States. Atlanta, GA: U.S. Department of Health and Human Services, CDC. Accessed May 30, 2023. http://www.cdc.gov/tb/statistics/reports/2007/default.htm
Centers for Disease Control and Prevention., (2007). Division of Tuberculosis Elimination Slide Set . [Online]. Accessed May 30, 2023. http://www.cdc.gov/tb/statistics/surv/surv2007/default.htm
Hernandez, J. B. R., & Kim, P. Y. (2019). Epidemiology morbidity and mortality.
Bottom of Form
|
