REHS COMPREHENSIVE UPDATED QUESTIONS
AND ANSWERS RATED A+
✔✔Observational Studies - ✔✔Simply observe the exposure and disease status of each
study participant.
✔✔Prospective Cohort Study - ✔✔Similar in concept to the experimental study. In a
cohort study, the epidemiologist records whether each study participant is exposed or
not, and then tracks the participants to see if they develop the disease of interest.
Participants are enrolled as the study begins and are then followed prospectively over
time to identify the occurrence of the
outcomes of interest.
✔✔Retrospective Cohort Study - ✔✔Both the exposure and the outcomes have already
occurred. Like in a prospective cohort study, the investigator
calculates and compares disease rates in the exposed and unexposed
groups.
✔✔Case-Control Study - ✔✔Investigators start by enrolling a group of people with a
disease. As a comparison group, the investigator then enrolls a group of people without
disease (controls). Investigators then compare previous exposures between the two
groups.
✔✔Cross-Sectional Study - ✔✔A sample of persons from a population is enrolled, and
their exposures and health outcomes are measured simultaneously. The cross-sectional
study tends to assess the presence (prevalence) of the health outcome at that point in
time without regard to duration. For example, in a cross-sectional study of diabetes,
some of the enrollees with diabetes may have lived with their diabetes for many years,
while others may have been recently diagnosed.
✔✔E. coli (food - ✔✔Caused by consuming contaminated and raw food, including
■ raw milk
■ undercooked ground beef
,■ raw leafy green vegetables
✔✔Listeria sources - ✔✔Found in dirt, water, and plants.
Linked to: Raw meat, unpasteurized dairy products, ready-to-eat food, commonly deli
meats
✔✔Cryptosporidium (P) sources - ✔✔Found in the feces of infected individuals
Commonly linked to contaminated water and produce
✔✔Campylobacter (B) sources - ✔✔Commonly associated with poultry and has been
known to contaminate water ○ The illness usually occurs when poultry is not cooked
correctly or is allowed to cross-contaminate other food or surfaces
✔✔HIV (V) sources - ✔✔HIV is caused by a virus. It can spread through sexual contact,
illicit injection drug use or sharing needles, contact with infected blood, or from mother
to child during pregnancy, childbirth, or breastfeeding.
It cannot be given to someone consuming food prepared by someone with HIV.
Exposure to air, heat from cooking, and stomach acid would destroy it.
✔✔Hantavirus (V) sources - ✔✔Normally infect rodents where they do not cause
disease. Humans may become infected with hantaviruses through contact with rodent
urine, saliva, or feces.
DEER MOUSE
✔✔Ebola Virus (V) source - ✔✔Viral hemorrhagic fever of humans and other primates
caused by ebolaviruses.
Between people, Ebola disease spreads only by direct contact with the blood or other
body fluids of a person who has developed symptoms of the disease.
✔✔West Nile Virus (V) Source - ✔✔Viral infection typically spread by mosquitoes. From
the following masquitos commonly Culex pipiens (Eastern United States, and urban and
residential areas of the United States north) Culex tarsalis (Midwest and West), and
Culex quinquefasciatus (Southeast)
✔✔Asian Bird Flu (V) - ✔✔Avian influenza is a disease caused by infection with avian
(bird) influenza (flu) Type A viruses. These viruses occur naturally among wild aquatic
birds worldwide and can infect domestic poultry and other bird and animal species.
Avian flu viruses do not normally infect humans.
✔✔Reservoir - ✔✔Any person, animal, plant, soil, or substance in which an infectious
agent normally lives and multiplies. The reservoir typically harbors the infectious agent
, without injury to itself and serves as a source from which other individuals can be
infected
✔✔Portals of Exit from a Reservoir - ✔✔Respiratory tract, Genitourinary alimentary,
skin, in utero, gastrointestinal, blood, mucous membranes
✔✔Direct Transmission - ✔✔Skin-to-skin, person-to-person, aerosol, or droplet
transmission. Occurs when there is physical contact between an infected person
and a susceptible person.
✔✔Indirect Transmission - ✔✔This occurs when the reservoir and the host are
separated. occurs when there is no direct human-to-human contact. Contact occurs
from a reservoir to contaminated surfaces or objects, or to vectors such as mosquitoes,
flies, mites, fleas, ticks, rodents, or dogs.
✔✔Active Immunity - ✔✔Results from the production of antibodies by the immune
system in response to the presence of an antigen. Attained by infection or inoculation.
✔✔Passive Immunity - ✔✔The short-term immunity that results from the introduction of
antibodies from another person or animal. Transplacental transfer.
✔✔Sanitization - ✔✔The process of reducing microbial contamination to an acceptable
"safe" level. The process of cleaning objects without necessarily going through
sterilization.
✔✔Sterilization - ✔✔The complete elimination or destruction of all forms of life by
chemical or physical means. This is an absolute, not a relative, term.
✔✔Antisepsis - ✔✔Typically, an antiseptic is a chemical agent that is applied to living
tissue to kill microbes. Note that not all disinfectants are antiseptics because an
antiseptic additionally must not be so harsh that it damages living tissue. Antiseptics are
less toxic than disinfectants used on inanimate objects
✔✔Disinfection - ✔✔A procedure of treatment that eliminates many or all pathogenic
microorganisms except bacterial spores.
✔✔Due process - ✔✔Refers to the necessary procedural requirements that government
agencies must follow to take action against parties violating applicable laws.
✔✔Statutes - ✔✔These are laws enacted by elected officials of the nation (Federal) or
state legislative body.
✔✔Ordinances - ✔✔These are laws enacted by local elected officials of the nation or
state, such as municipalities or counties.
AND ANSWERS RATED A+
✔✔Observational Studies - ✔✔Simply observe the exposure and disease status of each
study participant.
✔✔Prospective Cohort Study - ✔✔Similar in concept to the experimental study. In a
cohort study, the epidemiologist records whether each study participant is exposed or
not, and then tracks the participants to see if they develop the disease of interest.
Participants are enrolled as the study begins and are then followed prospectively over
time to identify the occurrence of the
outcomes of interest.
✔✔Retrospective Cohort Study - ✔✔Both the exposure and the outcomes have already
occurred. Like in a prospective cohort study, the investigator
calculates and compares disease rates in the exposed and unexposed
groups.
✔✔Case-Control Study - ✔✔Investigators start by enrolling a group of people with a
disease. As a comparison group, the investigator then enrolls a group of people without
disease (controls). Investigators then compare previous exposures between the two
groups.
✔✔Cross-Sectional Study - ✔✔A sample of persons from a population is enrolled, and
their exposures and health outcomes are measured simultaneously. The cross-sectional
study tends to assess the presence (prevalence) of the health outcome at that point in
time without regard to duration. For example, in a cross-sectional study of diabetes,
some of the enrollees with diabetes may have lived with their diabetes for many years,
while others may have been recently diagnosed.
✔✔E. coli (food - ✔✔Caused by consuming contaminated and raw food, including
■ raw milk
■ undercooked ground beef
,■ raw leafy green vegetables
✔✔Listeria sources - ✔✔Found in dirt, water, and plants.
Linked to: Raw meat, unpasteurized dairy products, ready-to-eat food, commonly deli
meats
✔✔Cryptosporidium (P) sources - ✔✔Found in the feces of infected individuals
Commonly linked to contaminated water and produce
✔✔Campylobacter (B) sources - ✔✔Commonly associated with poultry and has been
known to contaminate water ○ The illness usually occurs when poultry is not cooked
correctly or is allowed to cross-contaminate other food or surfaces
✔✔HIV (V) sources - ✔✔HIV is caused by a virus. It can spread through sexual contact,
illicit injection drug use or sharing needles, contact with infected blood, or from mother
to child during pregnancy, childbirth, or breastfeeding.
It cannot be given to someone consuming food prepared by someone with HIV.
Exposure to air, heat from cooking, and stomach acid would destroy it.
✔✔Hantavirus (V) sources - ✔✔Normally infect rodents where they do not cause
disease. Humans may become infected with hantaviruses through contact with rodent
urine, saliva, or feces.
DEER MOUSE
✔✔Ebola Virus (V) source - ✔✔Viral hemorrhagic fever of humans and other primates
caused by ebolaviruses.
Between people, Ebola disease spreads only by direct contact with the blood or other
body fluids of a person who has developed symptoms of the disease.
✔✔West Nile Virus (V) Source - ✔✔Viral infection typically spread by mosquitoes. From
the following masquitos commonly Culex pipiens (Eastern United States, and urban and
residential areas of the United States north) Culex tarsalis (Midwest and West), and
Culex quinquefasciatus (Southeast)
✔✔Asian Bird Flu (V) - ✔✔Avian influenza is a disease caused by infection with avian
(bird) influenza (flu) Type A viruses. These viruses occur naturally among wild aquatic
birds worldwide and can infect domestic poultry and other bird and animal species.
Avian flu viruses do not normally infect humans.
✔✔Reservoir - ✔✔Any person, animal, plant, soil, or substance in which an infectious
agent normally lives and multiplies. The reservoir typically harbors the infectious agent
, without injury to itself and serves as a source from which other individuals can be
infected
✔✔Portals of Exit from a Reservoir - ✔✔Respiratory tract, Genitourinary alimentary,
skin, in utero, gastrointestinal, blood, mucous membranes
✔✔Direct Transmission - ✔✔Skin-to-skin, person-to-person, aerosol, or droplet
transmission. Occurs when there is physical contact between an infected person
and a susceptible person.
✔✔Indirect Transmission - ✔✔This occurs when the reservoir and the host are
separated. occurs when there is no direct human-to-human contact. Contact occurs
from a reservoir to contaminated surfaces or objects, or to vectors such as mosquitoes,
flies, mites, fleas, ticks, rodents, or dogs.
✔✔Active Immunity - ✔✔Results from the production of antibodies by the immune
system in response to the presence of an antigen. Attained by infection or inoculation.
✔✔Passive Immunity - ✔✔The short-term immunity that results from the introduction of
antibodies from another person or animal. Transplacental transfer.
✔✔Sanitization - ✔✔The process of reducing microbial contamination to an acceptable
"safe" level. The process of cleaning objects without necessarily going through
sterilization.
✔✔Sterilization - ✔✔The complete elimination or destruction of all forms of life by
chemical or physical means. This is an absolute, not a relative, term.
✔✔Antisepsis - ✔✔Typically, an antiseptic is a chemical agent that is applied to living
tissue to kill microbes. Note that not all disinfectants are antiseptics because an
antiseptic additionally must not be so harsh that it damages living tissue. Antiseptics are
less toxic than disinfectants used on inanimate objects
✔✔Disinfection - ✔✔A procedure of treatment that eliminates many or all pathogenic
microorganisms except bacterial spores.
✔✔Due process - ✔✔Refers to the necessary procedural requirements that government
agencies must follow to take action against parties violating applicable laws.
✔✔Statutes - ✔✔These are laws enacted by elected officials of the nation (Federal) or
state legislative body.
✔✔Ordinances - ✔✔These are laws enacted by local elected officials of the nation or
state, such as municipalities or counties.
