Chapter 14 ppt

Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Chapter 14: Emerging Infectious Diseases


Chapter Highlights

• Emerging versus reemerging infectious diseases

• Factors that influence the emergence/reemergence of infectious diseases

• Recent emerging/reemerging infectious diseases

• Prevention and control of emerging infectious diseases


Question

Is the following statement True or False?

Factors that influence the emergence or reemergence of infectious diseases are multiple, complex, and interrelated.


Answer

True

Rationale: Factors that influence the emergence or reemergence of infectious diseases are multiple, complex, and interrelated.


Emerging Infectious Disease

• A newly identified clinically distinct infectious disease, or the reappearance (or reemergence) of a known infectious disease after its decline with an incidence that is increasing in a certain geographic area or in a specific population.


Factors That Influence Emerging Infectious Diseases• Convergence model—model illustrating the interaction of

13 factors that contribute to the emergence of infectious diseases

• There are following four types of interrelated and overlapping microbe–human interactions, which can lead to emerging/reemerging infectious diseases:

– Genetic and biological

– Physical/environmental

– Ecological

– Social, political, and economic


Question


Antigenic shift is the slow and progressive genetic changes that take place in DNA and RNA as organisms replicate in multiple hosts, cause changes in influenza viruses each year.


Answer

False

Rationale: Antigenic drift, the slow and progressive genetic changes that take place in DNA and RNA as organisms replicate in multiple hosts, causes changes in influenza viruses each year. Antigenic shift occurs when there is a sudden change in the DNA and RNA resulting in a new strain of the microorganism and people have little or no acquired immunity.


Microbial Adaptation

• Process by which organisms adjust and change to their environment


Microbial Adaptation and Change

• Antigenic drift, the slow and progressive genetic changes that take place in DNA and RNA as organisms replicate in multiple hosts, causes changes in influenza viruses each year.

• Antigenic shift occurs when there is a sudden change in the DNA and RNA resulting in a new strain of the microorganism and people have little or no acquired immunity.


Question


Epidemics and pandemics can place long-term demands on health care systems.


Answer

False

Rationale: Epidemics and pandemics can place sudden and intense demands on health care systems.


Microbial Adaptation Stages

• Epidemic

• Infection becomes endemic or continuously present in a geographic area or population of people.

• Symbiosis


Epidemiologic Triad

• A change in the behavior of humans—the host

• A change in the behavior of the microbes—the agent

• A change in the environment


Human Susceptibility to Infection

• Herd immunity—type of immunity in which a large proportion of people in a population are not susceptible to a communicable disease and the few people who are susceptible will not be likely to be exposed and contract the illness


Microbial Adaptation and Change

• Climate, changing ecosystems, and human behavior

– Ecosystems are groups of interacting living things that depend on each other for survival.

• Travel, technology, and industry

• Lack of political will and breakdown of public health infrastructures


Question


Certain zoonotic diseases can be transmitted to humans through contact with zoo animals.


Answer

False

Rationale: Certain zoonotic diseases can be transmitted to humans through contact with animals and birds.


Recent Emerging and Reemerging Infectious Diseases

• Severe acute respiratory syndrome

– Infection control for the prevention SARS-CoV transmission

• Avian influenza

– Infection Control for the prevention avian influenza transmission

• H1N1influenza (swine flu) pandemic

• Escherichia coli O157:H7


Personal Steps to Reduce Spread of Infection• Recognize symptoms of the flu and see a health care provider

immediately if you have any of the following:

– A temperature of greater than 100°F

– A cough

– A sore throat

– An underlying condition that increases risk

• Cover your cough or sneeze

• Wash hands often and keep hands away from your face

• Stay home and do not travel if you are ill

• Be prepared for increased illness in your schools and community


West Nile VirusCommunity and public health nurses should educate the

public about how to prevent WNV infection:

– Use Food and Drug Administration (FDA)-approved repellents on skin and clothing for protection from mosquito-borne diseases.

– When weather permits, wear long-sleeved shirts and long pants outdoors.

– Place mosquito netting over infant carriers when outdoors with infants.

– Consider staying indoors at dawn, dusk, and early evening, which are peak mosquito biting times.

– Install or repair window and door screens so that mosquitoes cannot come indoors


Lyme Disease

• Epidemiology

• Signs and symptoms

• Prevention


Tuberculosis• Epidemiology

• Geographic distribution

• Signs and symptoms

• Latent tuberculosis and human immunodeficiency virus infection

• Prevention and control of tuberculosis

– Targeted tuberculin testing and treatment of latent tuberculosis infection


Directly Observed Therapy

• Health care professionals observe clients to ensure that they ingest each dose of anti-TB medication, to maximize the likelihood of completion of therapy.


Diagnostic and Public Health Evaluation of Tuberculosis Contacts

• QuantiFERON-TB Gold test

• Multidrug-resistant tuberculosis

Chapter 14 ppt

Documents

known infectious disease

distinct infectious

health care systems

progressive genetic

multiple hosts

antigenic shift

following statement

cause changes