Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
66 Cards in this Set
- Front
- Back
|
Symbiosis |
the relationship between the normal microbiota and the host, where at least on organism is dependent on the other |
|
|
Microbial Antagonism |
competition between microbes |
|
|
ways Normal Microbiota protect the host |
1. Occupying niches that pathogens might occupy 2. Producing acids 3. Producing bacteriocins |
|
|
Probiotics |
live microbes applied to or ingested into the body, intended to exert a beneficial effect
|
|
|
Prebiotics |
chemicals that promote beneficial bacteria growth |
|
|
Opportunistic Microbes |
- usually don't cause disease in their normal habitat unless: 1. Host is weakened 2. Microbe is in a diff environment (E. coli in urinary tract) |
|
|
Polymicrobial diseases
|
"takes a village to cause a disease" - synergistic pathogenesis (microbial cooperation) |
|
|
Symptom |
a change in body function that is felt by a patient as a result of a disease (subjective feeeels) |
|
|
Sign |
a change in a body that can be measured or observed as a result of disease (objective, bruises af) |
|
|
Syndrome |
a specific group of signs and symptoms that accompany a disease |
|
|
Incidence |
fraction of a population that contracts a disease during a specific time |
|
|
Prevalence |
fraction of a population having a specific disease at a given time (total over time) - takes into account both old and new cases |
|
|
Sporadic Disease |
occurs occasionally |
|
|
Endemic Disease |
constantly present in a population |
|
|
Epidemic |
disease acquired by many hosts in a given area in a short time |
|
|
Pandemic |
worldwide epidemic |
|
|
Herd Immunity |
immunity in most of a population |
|
|
Acute |
symptoms develop rapidly - ie. influenza |
|
|
Chronic |
disease develops slowly, may be less sever but is likely to occur for long periods - ie. tuberculosis, hep B |
|
|
Subacute |
symptoms between acute and chronic |
|
|
Latent Disease |
causative agent remains inactive for a time but then becomes active to produce symptoms ie. shingles |
|
|
Local Infection |
pathogens are limited to a small area of the body ie. gonorrhea, boils |
|
|
Systemic Infection |
an infection throughout the body ie. measles |
|
|
Focal Infection |
system infection that BEGAN as a local infection ie. agents of a local infection enter blood of lypmhatic vessels and spread to other parts of the body ie. tonsils |
|
|
Bacteremia |
bacteria in the blood |
|
|
Septicemia |
growth of bacteria in the blood |
|
|
Toxemia |
toxins in the blood |
|
|
Viremia |
viruses in the blood |
|
|
Primary Infection |
acute infection that causes the initial illness |
|
|
Secondary Infection |
opportunistic infection after a primary (predisposing) infection |
|
|
Subclinical Disease |
no noticeable signs or symptoms (inapparent infection) |
|
|
Predisposing Factors (those that make the body more susceptible to disease) |
- short urethra in females - inherited traits such as the sickle-cell gene - climate and weather - fatigue - age - lifestyle - chemotherapy |
|
|
Stages of a Disease Infection enters host body, overcomes host defenses and initiates parasitism |
1. Incubation Period 2. Prodromal Period 3. Period of Illness 4. Period of Decline 5. Period of Convalescence |
|
|
Incubation Period |
Interval between initial infection and first signs or symptoms, may vary or be the same depending on: 1. microbe involved 2. virulence (degree of pathogenecity) 3. number of infecting microbes 4. resistance of host - for many diseases, most contagious period is last half of incubation period and prodromal period |
|
|
Prodromal Period |
appearance of nonspecific symptoms (fever, headache, malaise), hard to diagnose at this point - for many diseases, most contagious period time is last half of incubation period and prodromal period |
|
|
Period of Illness |
disease is most severe, over signs/ symptoms ie. chills, muscle pain, sensitivity to light - if disease is not overcome, patient DIES GATDAM |
|
|
Period of Decline |
signs and symptoms decline, patient vulnerable to secondary infections |
|
|
Period of Convalescence (Period of Recovery) |
regains strength, body returns to prediseased state - recovery has occurred - can still spread infection during this time, some pathogens remain alive in body - possibility of relapse (return of symptoms) |
|
|
Reservoirs of Infections |
Human - principal living reservoir Animal - both wild and domestic - Zoonoses - disease that occur in primarily in animals and can be transmitted to humans ex. rabies/lyme diease Nonliving - Soil - Water |
|
|
Transmission of Pathogens |
how pathogen is carried to a new host - point of exit from sick person will usually be same as point of entry for next infected person |
|
|
Contact (with infected host) |
1. Direct Contact - touching, direct physical contact between source and susceptible host ie. kissing, sex (rabies/anthrax) 2. Indirect Contact - via fomites (contaminated inanimate objects) ie. contaminated syringes (AIDS and HEP B) 3. Droplet Infection - saliva or respiratory discharges traveling through air for less than one meter
|
|
|
Vehicle Transmission |
transmission by an inanimate reservoir (food, water) 1. Waterborne - contaminated water/untreated or poorly treated sewage (leptospirosis) 2. Foodborne - incompletely cooked, poorly refrigerated, prepared under unsanitary conditions (food poisoning/tapeworm) 3.. Airborne pathogen carried by air for more than one meter ie. measles virus, fungus spores |
|
|
Vectors |
Arthropods, especially fleas, ticks, and mosquitoes Mechanical Vector Transmission: feet of insects touch you, etc Biological Vector Transmission: pathogen reproduces in vector and poop on your/trade blood/BITE THAT FOO |
|
|
Healthcare-Associated Infections (HAIS) or Nosocomial (Hospital-Acquired) Infections |
microbes in the hospital, acquired as a result of a hospital stay, 5-15% of all hospital patients acquire nosocomial infections |
|
|
Emerging Infectious Diseases (EIDs) |
diseases that are new, increasing in incidence or showing a potential to increase in the near future |
|
|
Contributing Factors to Emerging Infectious Diseases |
1. Genetic recombination 2. Evolution of new strains 3. Inappropriate use of antibiotics and pesticides 4. changes in weather patterns 5. Modern transportation 6. Ecological disaster, war, and expanding human settlement 7. Animal control measures 8. Public Health failure |
|
|
Epidemiology |
study of where and when diseases occur and how they are transmitted in populations |
|
|
Centers for Disease Control and Prevention, Atlanta, GA |
CDC, collects and analyzes epidemiological information in the US - publishes Morbidity and Morality Weekly Report (MMWR) Morbidity - incidence of specific notable disease Mortality - # of deaths for these diseases |
|
|
Transient Microbiota |
microbiota that disappears after days, weeks, or months |
|
|
Commensalism |
- one organism benefits, the other unaffected |
|
|
Mutualism |
- both organisms benefit |
|
|
Paratism |
- one organism derives nutrients at the expense of the other |
|
|
Communicable Disease |
an infected transmits an infectious agent, directly/indirectly to another person who also becomes infected |
|
|
Contagious |
easily communicable and rapid spreading disease |
|
|
Non-Communicable Disease |
not spread from host to another, spread by a microorganism entering the body (tetanus) or by a normal microorganism in the body that only occassionaly produces disease |
|
|
Sepsis |
a toxic inflammatory condition arising from the spread of microbes from a focus infection - may damage organs and cause them to fail |
|
|
Fomite |
any nonliving inanimate object involved in the spread of infection -ie. tissues, towels, bedding |
|
|
Compromised Host |
one whose resistant to infection is impaired by disease, therapy, or burns
2 Principal Conditions 1. broken skin or mucuous membranes 2. suppressed immune system |
|
|
Descriptive Epidemiology |
collecting all data that describe the occurrence of the disease under study - retrospective (looking back) |
|
|
Analytical Epidemiology |
analyzes a particular disease to determine probable cause 1. case control method - factors that preceded a disease 2. cohort method - two populations |
|
|
Experimental Epidemiology |
Hypothesis --> Experiment |
|
|
How can opportunistic pathogens cause infections? |
Opportunistic pathogens can cause infection because they are present in/on the body.They are called opportunistic because they usually do not cause healthy hosts harm but may cause disease to a host that is weakened, compromised by infection, has broken skin, or mucuous membranes. Opportunistic pathogens are more successful in environment such as hospitals due to the number of compromised hosts. |
|
|
Categorize disease according to frequency of occurrence |
Sporadic Endemic Epidemic Pandemic |
|
|
Categorize diseases according to severity or duration |
Acute Subacute Chronic Latent Disease |
|
|
Stages of Illness |
1. Incubation Period 2. Prodromal Period 3. Period of Illness 4. Period of Decline 5. Period of Convalescence |
|
|
k |
k |
