Chapter 14 (Final Review) - Medical Microbiology
Describe three modes of disease transmission.
-Contact Transmission -Air-borne Transmission -Vector Transmission
Contrast iatrogenic and nosocomial diseases.
-Iatrogenic disease: doctor induced infection -Nosocomial disease: infections from normal flora within the patient that became ill because of factors within the health care facility
List in the correct sequence five stages of infectious diseases.
-Incubation Period -Prodromal Period -Illness -Decline -Convalescence
Contrast the terms infection and morbidity.
-Infection is the process of invasion of a pathogen -Morbidity is any change from a state of health
List Koch's four postulates, and describe situations in which not all may be applicable.
-Suspected agent must be present in every case of disease -Agent must be isolated and grown in pure culture -Cultured agent must cause the disease when it is inoculated into healthy, susceptible experimental host -Same agent must be reisolated from the diseased experimental host
Which of the following phrases describes a contagious disease?
A disease that is passed from the host to host in aerosols
The nature of bacterial capsules
Affects the virulence of these bacteria
Which of the following types of epidemiologists is most like a detective?
An analytical epidemiologist
Infections that may go unnoticed due to the absence of symptoms are called
Asymptomatic infections
The study of where and when disease occur and how they are transmitted within populations is
Epidemiology
The study of the cause of a disease is
Etiology
Nonliving reservoirs of disease, such as a toothbrush, drinking glass, and needle are called
Fomites
Which of the following statements is the best definition of a pandemic disease?
It is an epidemic that occurs on more than one continent at the same time
A disease in which a pathogen remains inactive for a long period of time before becoming active is termed a(n)
Latent disease
Endotoxin, also known as _______ is part of the outer membrane of Gram-negative bacteria.
Lipid A
When pathogenic bacterial cells lose the ability to make adhesins, they typically
Become avirulent
An animal that carries a pathogen and also serves as host for the pathogen is a
Biological vector
An anemic environment is one that
Contains only one species
Diseases that are naturally spread from their usual animal hosts to humans are called
Zoonoses
_______ infections are those acquired by patients or staff while in health care facilities.
Nosocomial
Which of the following are most likely to cause disease?
Opportunistic pathogens in a weakened host
A microbe that causes disease is a
Pathogen
Describe the parental route of infection.
Pathogen that enters the body by cuts, bites, stab wounds, etc.
The total number of cases of a disease in a given area is its
Prevalence
In general, contrast transient microbiota with resident microbiota.
-Transient Microbiota are found in the same location as resident microbiota, but they do not remain there for long due to competition with other organisms. -Resident Microbiota are part of the normal microbiota that will not harm
List three portals through which pathogens enter the body
-skin -mucous membrane -placenta
The process by which microorganisms attach themselves to cells is
Adhesion
A patient contracted athlete's foot after long-term use of a medication. His physician explained that the malady was directly related to the medication. Such infections are termed
Iatrogenic infections
List three conditions that create opportunities for pathogens to become harmful in a human.
Immunosuppression New Normal microbiota on unusual site on body Changes in Normal Microbiota
Which of the following is the correct sequence of events in infectious diseases?
Incubation, prodromal period, illness, decline, convalescence
Consider the following the case. An animal was infected with a virus. A mosquito bit the animal, was contaminated with the virus, and proceeded to bite and infect a person. Which was the vector?
Mosquito
Which of the following is FALSE concerning microbial contaminants?
Most microbial contaminants will eventually cause harm
In which type of symbiosis do both members benefit from their interaction?
Mutualism
List three types of symbiotic relationships, give an example of each
Mutualism: Bacteria in the colon Commensalism: Staphylococcus epidermidis (on skin; doesn't cause harm) Parasitism: Ticks on humans cause infection
The most frequent portal of entry for pathogens is-
The respiratory act