28:Immunity and Vaccines

Acute infection

a short-term infection, usually characterized by dramatic onset

Basic reproduction number (R0)

the number of expected secondary transmissions from each single case of a disease in an entirely susceptible population

Biological warfare

the use of biological agents to incapacitate or kill a military or civilian population in an act of war or terrorism

Carrier

a subclinically infected individual who may spread a disease

Centers for Disease Control and Prevention (CDC)

the agency of the United States Public Health Service that tracks disease trends, provides disease information to the public and healthcare professionals, and forms public policy regarding disease prevention and intervention

Chronic infection

a long-term infection

Common-source epidemic

an infection (or intoxication) of a large number of people from a contaminated common source such as food or water

Emerging disease

an infectious disease whose incidence recently increased or whose incidence threatens to increase in the near future

Endemic disease

a disease that is constantly present, usually in low numbers, in a population

Epidemic

the occurrence of a disease in unusually high numbers in a localized population

Epidemiology

the study of the occurrence, distribution, and determinants of health and disease in a population

Fomite

an inanimate object that when contaminated with a viable pathogen can transfer the pathogen to a host

Herd immunity

the resistance of a population to a pathogen as a result of the immunity of a large portion of the population

Host-to-host epidemic

an epidemic resulting from person-to-person contact, characterized by a gradual rise and fall in number of new cases

Incidence

the number of new disease cases reported in a population in a given time period

Isolation

the separation of persons who have an infectious disease from those who are healthy

Morbidity

the incidence of disease in a population

Mortality

the incidence of death in a population

Outbreak

the occurrence of a large number of cases of a disease in a short period of time

Pandemic

a worldwide epidemic

Prevalence

the total number of new and existing disease cases reported in a population in a given time period

Public health

the health of the population as a whole

Quarantine

the separation and restriction of well persons who may have been exposed to an infectious disease to see if they develop the disease

Reemerging disease

an infectious disease previously under control but that produces a new epidemic

Reservoir

a source of infectious agents from which susceptible individuals may be infected

Surveillance

the observation, recognition, and reporting of diseases as they occur

Vector

a living agent that transfers a pathogen

Vehicle

a nonliving source of pathogens that transmits the pathogens to large numbers of individuals

Virulence

the relative ability of a pathogen to cause disease

Zoonosis

any disease that occurs primarily in animals but can be transmitted to humans