é NAMIBIA UNIVERSITY OF SCIENCE AND TECHNOLOGY

FACULTY OF HEALTH AND APPLIED SCIENCES

DEPARTMENT OF HEALTH SCIENCES

QUALIFICATION: BACHELOR OF ENVIRONMENTAL HEALTH SCIENCES & BACHELOR OF HEALTH

INFORMATION SYSTEM MANAGEMENT

QUALIFICATION CODE: O8BEHS/O8BHIS LEVEL: 6

COURSE: EPIDEMIOLOGY 2A COURSE CODE: EPD 6115S

SESSION: JUNE, 2018 PAPER: THEORY DURATION: 3 HOURS MARKS: 100

FIRST OPPORTUNITY EXAMINATION QUESTION PAPER

EXAMINER(S): MR E. NAKAFINGO

MRS R. MAHALIE MODERATOR:

THIS QUESTION PAPER CONSISTS OF 5 PAGES (EXCLUDING THIS FRONT PAGE)

INSTRUCTIONS

Answer All the questions

Write neatly and clearly

BWN

PR

PERMISSIBLE MATERIALS

Read the questions and instructions carefully

Begin each question on a separate sheet of paper and number the answers clearly

Page 1 of 6

SECTION A

QUESTION 1 [10MARKS]

Evaluate the following statements or phrases and select the most appropriate answer from

the options provided. Example 1.1 B

1.1 To assess the health of a population or community, public health officials may

consider identifying and analysing the following; [1]

A. The actual and potential health problems in the community including where they are

occurring

Populations at increased risk

The trend of health problems over time

Patterns in relation to the level and distribution of public health services available

All of the above moo

1.2 The Knowledge of the portals of exit and entry and modes of transmission of the

disease provides a basis for determining appropriate control measures which are

generally directed at; [1]

Decreasing the host’s defence

Controlling or eliminating agent at source of transmission

Estimating subgroups at highest risk

Eliminating the host

Increasing host susceptibility moO p

1.3 The epidemiologic triad of the disease causation refers to; [1]

Time, place, person

Agent, Host, Environment

Source, mode of transmission, susceptible host

All of the above

None of the above mOoOOWD

Within 10 days after attending a December wedding, an outbreak of Listerosis occurred

among attendees. Of the 83 guests and wedding party members, 79 were interviewed; 54 of the 79 met the case definition. The following two-by-two table shows consumption of a wedding cake (that had raspberry filling) and illness status.

ill Well Total

Wedding cake? Yes 50 | 3 53 No 4 22 26

Total 54 | 25 79

1.4 The fraction of 54/79 is: [1]

Food-specific attack rate

Attack rate

Incidence proportion

Proportion

Prevalence moOO@>

Page 2 of 6

1.5 Determine what type of data or information is missing from the case definition below; [1]

“Measles Case Definition (Suspect): Any person residing in Mozambique with a temperature

greater than 38°C (100°F) and a generalized rash”

Person

Clinical signs and symptoms

Place

Time

All of the above moO

>}

1.6 Which of the following is NOT part of Standard Precautionary Measures [1]

Hand hygiene

Use of Personal Protective Equipment (PPE)

Waste management

Vaccination

Cleaning and decontamination of re-useable medical moo

p>

1.7 Non Communicable Diseases are generally characterised by: [1]

Multiple risk factors and presents with Long latency period

Complex and uncertain etiology

Non-contagious origin

Prolonged course of illness with functional impairment or disability

All of the above moon >

1.8 The first step of a basic outbreak investigation is to: . [1]

A. Define a case and conduct case finding; Verify the diagnosis and confirm the outbreak;

Generate and test hypothesis

B. Tabulate and orient data: time, place, person; Define a case and conduct case

finding; Communicate findings

C. Verify the diagnosis and confirm the outbreak; Tabulate and orient data by time, place,

person; Generate and test hypothesis

D. Plan and execute additional studies; Generate and test hypothesis; Take immediate

control measures

E. Tabulate and orient data by time, place and person, verify the diagnosis and confirm

the outbreak; Generate and test hypothesis

1.9 In a country, notification of Meningitis is mandatory for all health care providers. They

are obliged to notify the Public Health authorities within 24 hours after the diagnosis by

telephone. Laboratories do not notify identification of Neisseria. Meningitis to

the authorities.

Page 3 of 6

This is an example of a; [1]

An active surveillance system

Sentinel surveillance system

Passive surveillance system

Community surveillance system

Selective surveillance system moonp7 Pp

1.10 Sources of outbreak reports include [1]

Physicians and Citizens

Surveillance data

Media

Rumours

All of the above moO

P >

QUESTION 2 [LOMARKS]

Indicate which of the following statements is TRUE or FALSE.

2.1 An outbreak (or epidemic) is an increase in the observed number of cases of a disease or health problem compared with the expected number for a given place or among a specific group of people over a particular period of time. [1]

2.2 One of the benefits of a case definition is that it allows us to compare numbers under investigation. [1]

2.3 The x-axis of an epidemic curve represents the number of cases [1]

2.4 A disease that spreads through the bite of an insect is called a vehicle-borne disease. [1]

2.5 A hypothesis is an educated guess about the relationship between an exposure and an outcome. [1]

2.6 A behavioural risk factor can be reduced or controlled by an intervention, thereby

reducing the probability of disease. [1]

2.7 Primary prevention aim to reduce the negative impact of established disease by

restoring normal functioning and reducing related complications. [1]

2.8 A disease that is not yet clinically apparent but is destined to progress to clinical disease is known as a sub-clinical disease. [1]

2.9 The percentage of a population required to be immune for herd immunity to operate varies from disease to disease. [1]

2.10 A carrier may never show signs and symptoms the time they are infected or may be incubatory but capable of transmitting the disease. [1]

Page 4 of 6

QUESTION 3 [10 MARKS]

Match the statement in column 1 to the corresponding concept(s) in column 2.

Write your answer in the answer booklet. Example 3.3 A (Each correct answer earns

one mark).

Column 1 Column 2

3.1 Help to protect against contamination | A | Metabolic risk factors

and spread of infections

3.2 Resistance to an attack by a disease to | B_ | Pathogenicity

which a large proportion of the group is

immune

3.3. | Ability of an agent to induce/cause a | C | Nosocomial Infection

clinical disease in a susceptible host

3.4 | Transmissible under natural conditions | D | Virulence

from vertebrate animals to humans

3.5 | Screening and treatment E | Personal Protective

Equipment(PPE)

3.6 | All cases that developed the disease | F | Secondary prevention

were in person exposed to the water or

food in question

3.7 | An infection occurring in a patient | G | Herd Immunity

during the process of care in a hospital

3.8 | Tobacco use, Alcohol use and Physical | H | Immunity

inactivity

3.9 Raised blood pressure and cholesterol | | Common-vehicle exposure

are examples of......

3.10 | Is habitually present in human|J | Zoonosis

population

K_ | Primary prevention

L | Endemic

M | Modifiable risk factors

N | Multiple exposure

Page 5 of 6

SECTION B

QUESTION 4 [10 MARKS]

Define the following terms:

4.1 Reservoir [2] 4.2 Epidemiology [2] 4.3 Sub-clinical disease [2]

4.4 Pandemic [2]

4.5 Eradication [2]

QUESTION 5 [30 MARKS]

5.1 List four important periods in relation to the natural history of an infectious disease [4]

5.2 Distinguish between live attenuated vaccines and inactivated vaccines [4]

5.3 Epidemiologic transition focuses on the complex change in patterns of health and disease

as well as on the interactions between these patterns. Describe factors that are associated

with epidemiological transition [6]

5.4 One of the use of epidemiological evidence is to identify high-risk population groups in

order to inform and direct prevention and control efforts. With clear and concise examples,

elaborate on the concept of prevention with reference to the following levels of prevention.

5.4.1 Primary prevention [2]

5.4.2 Secondary prevention [2]

5.4.3 Tertiary prevention [2]

5.6 Explain the chain of infection and its implication of public health [10]

SECTION C

QUESTION 6 [30 MARKS]

6.1 Once the decision to conduct a field investigation of an acute outbreak has been made,

working quickly and neatly is essential. Usually, the Epidemiologists find it useful to have

a systematic approach to follow as to ensure that the investigation proceeds without

missing important steps along the way. Discuss the epidemiologic steps of an outbreak

Investigation. [15]

6.2 Describe the Standard Precautions of Infection Control [10]

6.3 Discuss the importance of vaccine safety [5]

6.4 Explain the relationship between Communicable Diseases and Non Communicable

Diseases. [5]

END OF EXAMINATION PAPER

TOTAL: 100 MARKS

Page 6 of 6