Question | Answer |
a complete, fully developed, infectious viral particle | Virion |
protein subunits, a single type or several types | Capsomeres |
phage causes lysis and death of host cell | Lytic cycle |
prophage DNA incorporated in host DNA | Lysogenic cycle |
nucleic acid and capsid proteins assemble, usually a spontaneous process | Maturation |
Virus remains in asymptomatic host cell for long periods (cold sores, shingles) | Latent viral infections |
Disease process occurs over a long period; generally is fatal | Persistent viral infections |
cancer patients usually die of what kind of infection? | Microbial infections |
when animal viruses infect animal cells, the virus shape changes or stays the same? | changes |
Virus invades what and takes over what in order to multiply? | host cells; host's metabolic machinery |
what are the two types of bacteriophages? | lytic and lysogenic |
phages kill hosts right away | lytic cycle |
can the viruses in the lysogenic cycle spread diseases? | yes |
| |
Spikes are what? | glycoproteins |
how do viruses cause cancers? | viruses trigger the activation of oncogenes; oncogenic viruses become integrated into the host cell's DNA |
What are characteristics of transformed cells? | -increased growth
-chromosomal abnormalities |
which DNA viruses cause cancer? | -Papillomaviruses
-Hepatitis B virus
-Epstein-barr virus |
what is the characteristic of Burkitt lymphoma? | swollen face/neck |
Which RNA viruses cause cancer? | retroviruses (ex: leukemia virus) |
when DNA makes RNA | transcription |
when RNA makes DNA | reverse-transcriptase |
Are oncogenic viruses examples of latent infections or persistent infections? | |
Are cold sores latent or persistent infections? | Latent infections |
How does chickenpox virus cause shingles? | some people can still have chickenpox virus in their nerve cells |
the scientific study of disease | Pathology |
the study of the cause of a disease | Etiology |
the manner in which disease develops by pathogens | Pathogenesis |
invasion or colonization of the body by pathogens | Infection |
an abnormal state in which the body is not functioning normally | Disease |
microbiota that permanently colonizes the host | Normal microbiota |
microbiota that may be present for days, weeks, or months | Transient microbiota |
relationship between normal microbiota and the host | Symbiosis |
one organism benefits, and the other is unaffected | Commensalism |
both organisms benefit | mutualism |
one organism benefits at the expense of the other (pathogen vs. host) | Parasitism |
some normal microbiota are what? | opportunistic pathogens |
What accounts for up to 10% of energy a human body absorbs? | short chain fatty acids |
competition between microbes | microbial antagonism |
Normal microbiota protect the host by doing what? | -occupying niches that pathogens might occupy
-produce acids
-produce bacteriocins |
live microbes applied to or ingested into the body, intended to exert a beneficial effect | Probiotics |
a subjective change in a body function that is felt by a patient as a result of disease | Symptom |
an objective change in a body that can be measured or observed as a result of disease | Sign |
a specific group of signs and symptoms that accompany a disease | syndrome |
a disease that is spread from one host to another | Communicable disease |
a disease that is easily spread from one host to another | Contagious disease |
a disease that is not transmitted from one host to another | Noncommunicable disease |
new cases of a disease in a population during a specified time period | Incidence |
total cases of a disease in a population at a given time | Prevalence |
disease that occurs occasionally in a population | Sporadic disease |
disease constantly present in a population | Endemic disease |
disease acquired by many hosts in a given area in a short time | Epidemic disease |
worldwide epidemic | Pandemic disease |
disease in which symptoms develop rapidly | acute disease |
disease that develops slowly | chronic disease |
disease with a period of no symptoms when the causative agent is inactive | latent disease |
pathogens are limited to a small area of the body | Local infection |
an infection throughout the body | systemic infection |
when a local infection spreads to another site in the body | focal infection |
toxic inflammatory condition arising from the spread of microbes, especially bacteria or their toxins | sepsis |
blood poisoning, growth of bacteria in the blood | Septicemia |
bacteria in the blood | bacteremia |
toxins in the blood | toxemia |
viruses in the blood | viremia |
acute infection that causes the initial illness | primary infection |
opportunistic infection after a primary (predisposing) infection | secondary infection |
no noticeable signs or symptoms (inapparent infection) but can spread | subclinical disease |
incidence of a specific disease in a given time period | morbidity |
deaths from a specific disease in a given time period | mortality |
AIDS, gonorrhea, hepatitis, streptococcal infections | Human reservoirs |
carriers may have ____ infections or _____ diseases | inapparent; latent |
primarily animal diseases but can cause human diseases | zoonoses |
nonliving reservoirs? | soil and water |
transmissions of disease? | -contact
-vehicles
-vectors |
transmission of disease requires close association between infected and susceptible host | direct contact |
transmission of disease spread by fomites | indirect contact |
transmission of disease via airborne droplets | droplet contact |
transmission by an inanimate reservoir (food, water, air) | vehicle transmission |
animals that carry pathogens from one host to another | vectors |
infections acquired in hospitals, nursing homes and other health care facilities | nosocomial infections |
what type of infections affect 5-15% of all hospital patients | nosocomial infections |
____ million people per year contract nosocomial infections and nearly _____ die as a result | 2; 200,000 |
the study of where and when diseases occur and how they are transmitted | Epidemiology |
collects and analyzes epidemiological info in the U.S. | Centers for Disease Control and Prevention (CDC) |
-arthropod carries pathogen on feet
-food poisoning by houseflies | mechanical transmission |
-pathogens that reproduce in vector
-malaria (Plasmodium spp.) by mosquito
-plague (Yersinia pestis) by flea | Biological transmission |
What is the difference between pathology and pathogenesis? | pathology is not limited to any specific disease, pathogenesis is the series of events of pathogens |
Patients of HIV do or don't show symptoms right away? | Don't |
when do humans start to have microbiota? | once you're born |
Are pathogens normal or transient microbiota? | transient |
Are all transient microbiota pathogens (cause disease)? | no |
where are normal microbiota on the human body? | Eyes, mouth, skin, nose, throat, urinary tract, large intestine (none in womb) |
Of what value are normal microbiota? | 1-2.5 |
what is the difference between commensalism, mutualism, and parasitism? | -commensalism: one organism benefits, the other unaffected
-mutualism: both organisms benefit
-parasitism: one organism benefits at expense of another |
Normal microbiota can be what kind of pathogen? | opportunistic pathogens |
what nutrients are produced by intestinal microorganisms? | Vitamin B complexes, Vitamin K complexes, enzymes for carbohydrates, fatty acids for energy |
10% of energy a human body absorbs is? | short chain fatty acids |
How do normal microbiota protect us from microbial infections? | -preoccupy space so pathogens don't
-produce acids
-produce bacteriocins (which produce acids that kill pathogens) |
How did Warren and Marshall prove that H. pylori causes gastritis and peptic ulcer disease? | found microorganisms in patient's stomach (no one believed him), grew the microorganism and drank it, got the disease and proved it; accomplished kock's postulate |
difference between symptoms and signs? | signs can be measured by a physician, symptoms can only be felt by a patient |
Is cholera communicable or noncommunicable? | communicable |
What is the difference between incidence and prevalence? | incidence is NEW cases of a disease, prevalence is the TOTAL cases of a disease |
are seasonal diseases incidence or prevalence? | incidence |
Are colds sporadic, endemic, epidemic, or pandemic? | endemic |
is aids sporadic, endemic, epidemic, or pandemic? | epidemic |
is the flu sporadic, endemic, epidemic, or pandemic? | endemic |
are rabies sporadic, endemic, epidemic, or pandemic? | sporadic |
what are examples of acute diseases? | influenza, acute infection |
what are examples of chronic diseases? | tuberculosis, hepatitis B |
What are examples of latent disease? | shingles by varicella (or herpes) zoster virus |
how do latent infections differ from persistent infections? | latent do not show symptoms but persistent do |
What are examples of local infections? | boils, abscesses |
What are examples of systemic infections? | HIV, measles |
Is a toxigenic disease local, systemic, or focal? | systemic |
Does bacteremia (bacteria in the blood) always cause sepsis? | no; septicemia causes sepsis |
What is an example of primary disease? | HIV |
What is an example of secondary disease? | pneumonia |
What is an example of subclinical disease? | hepatitis A virus |
what is the difference between morbidity and mortality? | mortality= deaths
morbidity= incidence |
why do carriers and latent infection patients play an important role in the spread of infectious diseases? | they have viruses but DON'T show any symptoms and signs |
primarily animal diseases but can cause human diseases? | zoonoses |
What are major nonliving reservoirs of infectious diseases | soil, water |
What are 3 major modes of disease transmission? | -contact
-vehicles
-vectors |
What are the three contact modes in disease transmission? | -direct
-indirect
-droplet |
Vehicle transmission is mediated by what? | -inanimate reservoir (food, water, air) |
What are differences between droplet transmission and airborne vehicle transmission? | airborne vehicle: tuberculosis
Droplet: coughing, sneezing |
What animals are the most important group of disease vectors? | arthropods (fleas, ticks, mosquitoes) |
What are characteristics of microorganisms in hospital environment? | -resistant to antibiotics
-biofilm formation |
what are three factors causing nosocomial infections? | -microorganisms in hospital environment
-compromised host
-chain of transmission |
why are hospital patients vulnerable for infections? | -too many things attached to their body
-catheters (used to drain urine) can contain biofilms |
top infections in nosocomial infections? | -urinary tract infections
-surgical site infections
-lower respiratory infections |
What are main causes of each nosocomial infection? | -respiratory infections through ventilators |
what microorganisms usually cause nosocomial infections? | opportunistic pathogens |
how can nosocomial infections be controlled? | -aseptic techniques
-not sharing disposables
-handwashing
-education |
What is the main govt. agency to study epidemiology in the U.S? | Centers for Disease Control and Prevention (CDC) |
Who reports the nationally notifiable infectious diseases to whom? | physicians to CDC |
Is 100% immunization required for control of infection in pop.? Why? | no, most people being vaccinated can help stop the spread of a disease (90%) |
immunity in most of a population? | Herd immunity |
eating what can give you good bacteria? | eating yogurt |
what kind of disease is rabies? | sporadic disease |