Infection Disease & Covid-19 – Epidemiology
This chapter is about Infection Disease & Covid-19 – Epidemiology
Select all the symptoms that may be caused by COVID-19
Sneezing
Fatigue
Runny or Stuffy Nos
Aches and Pains
Shortness of Breath
Headaches
Fever
Sore Throat
Cough
Evidence shows that COVID-19 spreads through close personal contact – within about 6 feet or 2 meters.
True
Students that have COVID-19 symptoms should contact Holzer Health Center right away.
True
Where should you wear a facemask?
In public or shared spaces
Students will have to show up in a classroom in order to receive course materials.
False
Secondary infections
Caused by an opportunistic infection after a primary (predisposing) infection
Subclinical (inapparent) infection
No noticeable signs or symptoms (inapparent infection)
Predisposing Factor
Anything that makes the body more susceptible to disease
Incubation period
Time interval between the actual infection and first appearance of any signs or symptoms of disease
Prodromal period
The time following the incubation period when the first symptoms of illness appear
Period of Illness
Disease is more severe
Period of decline
Signs and symptoms decrease
Period of Convalescence
The recovery period
Reservoir of infection
A continual source of infection
Carriers
People that harbor pathogens and transmit them to other
Zoonoses
A disease that occurs primarily in animals but can be transmitted to humans
Contact transmission
Is the spread of an agent of disease by direct contact, indirect contact or droplet transmission
Direct contact transmission
Requires close association between infected and susceptible host
Indirect contact transmission
Spread by fomites. Occurs when the agent if disease is transmitted from its reservoir to a susceptible host by means of a nonliving object
Fomite
A nonliving objects that can spread infections
Droplet transmission
Transmission via airborne droplets
Vehicle transmission
Transmission by a medium
Vectors
An arthropods that carries disease causing organisms from one host to another
Mechanical transmission
Is the passive transport of the pathogens on the insect’s feet or other body parts
Biological transmission
Is an active process and is more complex that pathogens reproduces in vector
Composed host
A host whose resistance to infection is impaired
Emerging infectious disease (EIDs)
A new or changing disease that is in the past, present, and future
Epidemiology
The study of where and when diseases occur
Descriptive epidemiology
Collection and analysis of data
Analytical epidemiology
A disease is analyzed to determine its cause
Experimental epidemelogy
The study of disease using controlled experiments
Case reporting
Health care workers are required to report specified disease to local, state, and national offices
Nationally notifiable disease
Physicians are required to report occurrence
Centers for Disease Control and Prevention (CDC)
A branch of the U.S. Public Health Services
Morbidity
Incidence of a specific notifiable disease
Mortality
Deaths from notifiable diseases
Morbidity rate
Number of people affected in relation to the total population in a given time period
Mortality rate
Number of deaths from a disease in relation to the population in a given time
Notifiable infectious diseases
Are diseases that the U.S. physicians are required by law to report to the Public Health Services
Pathogens
disease-causing microorganism
Pathology
Is the scientific study of disease
Etiology
The study of cause of a disease
Pathogenesis
The development of a disease
Infection
Colonization of the body by pathogens
Disease
An abnormal state in which the body is not functioning normally
Pathogen
A disease causing microorganism
Normal Microbiota
Permanently colonize the host but do not cause disease
Transient Microbiota
May be prevented for days, weeks, or months than disappear
Symbiosis
The living together of two different organisms or population
Commensalism
One of the organisms benefits, and the other is unaffected is the symbolic relationship
Microbial antagonism
The growth of some microbes prevents the growth of other
Competitive exclusion
Growth of some microbes prevents the growth of other microbes
Mutualism
Is a type of symbiosis that benefits both organisms
Probiotics
Are live microbial cultures applied to or ingested that are intended to exit a beneficial effect
Parasitism
One organism benefits by deriving nutrients at the expensive of the other
Prebiotics
Chemicals to promote the growth of beneficial bacteria
Opportunistic Pathogens
A microorganism that does not ordinarily cause a disease but can become pathogens under certain circumstances
Koch’s postulates
Criteria used to determine the causative agent of infectious disease
Etiology
The study of the cause of a disease
Symptoms
A change in body function that is felt by a patient as a result of disease
Signs
A change in a body that can be measured or observed as a result of disease
A specific group of signs and symptoms that accompany a particular disease
Communicable disease
A disease that is spread from one host to another
Contagious disease
A disease that is easily spread from one host to another
Noncommunicable disease
A disease that is not transmitted from one host to another
Incidence
Fraction of a population that contracts a disease during a specific time period
Prevalence
Fraction of a population having a specific disease at a given time
Sporadic disease
Disease that occurs only occasionally in a population
Endemic disease
Disease constantly present in a population
Epidemic disease
Disease acquired by many people in a given area in a short time
Pandemic disease
Worldwide epidemic
Chronic disease
Disease develops slowly
Subacute disease
Disease with symptoms between acute and chronic
Latent disease
Disease with a period of no symptoms when the causative agent is inactive
Herd immunity
The presence of immunity in most of a population
Local infection
Pathogens are limited to a small area of the body
Systemic (generalized) infection
An infection throughout the body
Focal infection
Systematic infection that began as an infection in one place
Sepsis
Toxic inflammatory conditions arising from the spread of microbes (pathogens), especially bacteria or their toxins, from a focus of infection
Septicemia
(blood poising) growth of pathogens in the blood
Bacterium
Bacteria in the blood
Toxemia
Toxins in the blood
Viremia
Viruses in the blood
Primary Infections
Acute infections that causes the initial illness