Midterm 2 Review (4-7) Flashcards
What is the symbiotic relationship in which one organism benefits at the expense of the host?
Parasitism
What type of parasite is found internally?
Endoparasite
What type of parasite is found on the skin and hair?
Ectoparasite
What are the two classifications of parasites?
Protozoans and Helminths
What is the active-growing form of the Protozoa called?
Trophozoite
What is the non-growing form of a Protozoa called?
Cyst
What type of Protozoa does not have the ability to move and reproduces by simple fission?
Sporozoa
What is the etiological agent for Malaria?
Plasmodium falciparum
What is the vector of transmission for Malaria?
Mosquito
What is the most prevalent parasitic disease worldwide?
Malaria
What is the etiologic agent of Toxoplasmosis?
Toxoplasma gondii
What is the vector of transmission of Toxoplasma?
Feces of infected domestic cats
What is the largest class of Protozoa that use flagella as its method of locomotion?
Mastigophora
What species of Protozoa only exists in the trophozoite form?
Mastigophora
What is the vector of transmission of Trichomonas vaginalis?
Sexually transmitted disease
What are some of signs and symptoms of a Trichomonas infection?
-Persistent vaginitis in females
-Prostatitis and urethritis in chronic infection in males
What is the etiologic agent for Sleeping sickness?
Tryponosoma
What is the vector of transmission for Tryponosoma infections?
Tsetse fly
What country is the Sleeping Sickness confined to?
Central Africa
What are some of the signs and symptoms of African Sleeping Sickness?
Fever, headache, impaired mental status leading to coma and death
What is the etiologic agent of Beaver Fever?
Giardia lamblia
What is the vector of transmission of a Giardia infection?
Fecal-oral
What are some of the signs and symptoms of Beaver Fever?
Diarrhea, cramping, flatulence, and anorexia
What is the etiologic agent of Oriental Sores?
Leishmania species
What is the vector of transmission for a Leishmania infection?
Sand flea
What is the pathogenesis of Oriental Sore?
Lymphadenopathy, Depigmented scar, itchy pustules (appears weekly to months after bite)
What is the only species of ciliate that infects the human intestines?
Balantidium coli
What is the vector of transmission of a Balantidium infection?
Fecal-oral (pig feces)
What are the two phyla of Helminths?
Platyhelminthes (flatworms) and Nemahelminths (roundworms)
What type of Helminths belongs to the class Cestodes?
Tapeworms
What type of Helminths belong to the class Trematodes?
Flukes
What type of Helminths belong to the class Nematodes?
Roundworms
What is the basic structure of a Cestode?
Scolex, regenerative neck region, and long segmented body
What is the function of a Scolex in a Tapeworm?
Attachment to epithelium
What is the function of the Mature Proglottids of a Tapeworm?
Sexually maturing section
What is the pathogenesis of a Tapeworm Infection?
-Can live in humans for decades
-Cause gastric discomfort, nausea, diarrhea, and weight loss
What are the requirements for a successful infection?
Entry, Establishment, Defeat host defenses, Damage the host, Exit the host to be transmitted to another host
What is the most common portal of entry for infection?
Respiratory tract
What is the second most common portal of entry for infection?
Gastrointestinal tract
Microbes that infect the genitourinary tract are sometimes called?
Sexually transmitted diseases
What route of infection refers to breaks in the skin a that allows the passage of microbes?
Parenteral
What factors are reasons why females obtain more urinary tract infections than males?
Shorter urethra and proximity to anus
What is the inherent ability of a pathogen to protect themselves via intrinsic or extrinsic factors against the host’s defenses?
Passive defense
What kind of defense attacks the host defense?
Active defense
What substance is found only in the walls of all gram + bacteria and inhibits phagocytosis?
M proteins
What feature of a Gram- cell wall produces an endotoxin that elicits a powerful immune response?
Lipid A
What cell wall feature is exhibited in Mycobacterium species that inhibits phagocytosis and antibiotics?
Mycolic acid
What type of bacterial enzyme destroys WBCs?
Leukocidins
What type of bacterial enzyme destroys both RBCs and WBCs?
Hemolysins
What type of bacterial enzyme forms fibrin clots?
Coagulase
What type of bacterial enzyme breaks down fibrin and destroys clots?
Kinase
What type of bacterial enzyme breaks down connective tissue?
Hyaluronidase
What type of bacterial enzyme breaks down collagen?
Collagenase
How many categories of bacteria toxins are there?
2 categories
What type of exotoxin kills cells?
Cytotoxins
What type of exotoxin interferes with neurological signaling?
Neurotoxins
What type of exotoxin affects the lining of the digestive tract?
Enterotoxins
What is the most dangerous effect of endotoxin poisoning?
Disseminated intravascular clotting
What are some examples of bacteria that produces cytotoxins?
Bacillus anthracis and Corynebacterium diphtheraie
What are some examples of bacteria that produce neurotoxins?
Clostridium tetani and Clostridium botulinum
What is the pathogenesis of a Clostridium tetani (Tetanus) infection?
-Toxin enters presynaptic terminals of lower motor neurons
-Patient presents with “Lockjaw” and Opisthotonus (feet touch the back of the head)
Lockjaw is the common name for what disease?
Tetanus
What is the pathogenesis of a Clostridium botulinum (Botulism) infection?
-Inhibits release of acetylcholine
-Flaccid paralysis of skeletal muscle
-Begins as cranial nerve palsy (blurred or double vision)
A place where pathogens grow and accumulate is called?
Reservoir
What diseases are transmitted from animals to humans called?
Zoonotic
When an uninfected person is exposed to a pathogen via touching an infected reservoir, what type of contact transmission has occurred?
Direct contact transmission
When an uninfected person is exposed to a pathogen via touching an infected fomite, what type of contact transmission has occurred?
Indirect contact transmission
When an uninfected individual inhales infected particulate matter expelled from an infected person, what type of contact transmission has occurred?
Droplet transmission
What type of transmission occurs when a pathogen “rides”?
Vehicle transmission
A biological vector transmission includes what?
Found inside insect (bites)
A mechanical vector transmission includes what?
Found on insect body parts touching objects
What is the most common vector of transmission?
Arthropods (mosquitoes, ticks, fleas0
The hosts ability to mount an immune defense is called?
Immunocompetence
What idea is Koch’s Postulates associated with?
Disease transmission and communicability
In an illness, the earliest period free of signs and symptoms is called?
Incubation period
In an illness, the first sign and symptoms of a disease appear in what period?
Prodromal period
In an illness, the period of major signs and symptoms that produces an immune response is called?
Period of illness
In an illness, the period that has the highest chance of secondary infection is called?
Period of decline
What is the study of the factors and mechanisms involved in the frequency and spread of a disease?
Epidemiology
The total number of people infected within a population at any given time is called?
Prevalence
The number of new cases contracted within a set population in a specific period is called?
Incidence
The number of individuals affected by a disease during a set period divided by the total population is called?
Morbidity
The number of deaths due to a specific disease during a specific period divided by the total population is called?
Mortality
What type of disease is found constantly within a population?
Endemic disease
What type of disease is found suddenly higher than expected in a specific region?
Epidemic disease
What are some of the characteristics of a Common Source Epidemic?
-Arises from contacts with contaminated substances
-Affects large number of people but once source is identified quickly subsides
What are some of the characteristics of a Propagated Epidemic?
- Amplification for the number of infected individuals as person-to-person contact occurs
- Stays in the population for longer periods
- More difficult to control (“Patient Zero”)
Patient zero is most commonly associated with what type of disease?
Propagated epidemic disease
What type of disease occurs in epidemic proportions throughout the world?
Pandemic disease
What phase of a pandemic is COVID-19 in right now?
Post-peak
What type of study is concerned with the physical aspects of patients and the spread of disease?
Descriptive Study
What type of study focuses predominantly on cause and effect?
Analytical Study
What type of study always uses a control group?
Analytical Study
What nationally notifiable disease should never be seen again?
Smallpox
What type of infection is acquired in a hospital/medical facility within 48 hours of visit?
Nosocomial Infections
What is the most common organism in Nosocomial Infections?
Staphylococcus aureus
What type of microbe are known as obligate intracellular parasites?
Viruses
Infections that have never been seen before are considered?
Emerging infectious diseases
What kinds of diseases are considered Emergent diseases?
Zika, Dengue hemorrhagic, Chikungunya, MERS, and COVID-19
Diseases that were once thought of as being under control primarily due to antibiotics, vaccinations and insect control are considered?
Re-emerging infectious diseases
What kind diseases are considered re-emerging infectious diseases?
Whooping cough, diphtheria, measles, mumps, polio
What type of disease is condensed to India, Southeast Asia, and Micronesia that causes encephalitis or respiratory illness?
Nipah virus
What is the vector of transmission for Nipah virus?
Fruit bats
What is the most deadly form of influenza?
Avian influenza
What emerging illness presents with fever and joint pain and is transmitted via infected mosquitoes?
Chikungunya Virus
What type of virus causes Middle East Respiratory Syndrome (MERS)?
Coronavirus
What type of virus entered the US in 1999 and is found in most states?
West Nile Virus
What is the vector of transmission for West Nile Virus?
Mosquito
What is the deadliest type of viral hemorrhagic fevers?
Ebola
What type of virus is transmitted to a human host by an insect bite?
Arboviruses
Most of the emerging disease are considered what etiologic agent?
Viruses
The stable reservoir of influenza is found where?
Aquatic birds
What is the cause for the high TB rates in Africa?
HIV/AIDS epidemic
What country has the highest TB rates that immigrate to the US?
Mexico
What possible ways can a prion be treated with?
Cannot be destroyed (Resistatnt to cooking, autoclaving, disinfectants, and strong alkali treatment)
Transmissible spongiform encephalopathies (TSEs) are considered what type of infection?
Prions
What test is done to determine if a prion infections is present?
ELISA
What was the first seen TSE found in sheep?
Scrapies (1762)
What is the human version of TSE called?
Creutzfeldt-Jakob Disease (can be new variant)
What type of prion disease is spread in humans via cannibalism?
Kuru
What is the medical term for whooping cough?
Pertussis
80% of all acute respiratory tract infections are what type of microbe?
Viruses
What is the mortality rate for uncomplicated influenza?
0.1-2.5%
What is the vector of transmission of Sin Nombre?
Inhalation of dried rodent urine and feces
What virus is known as “Sin Nombre” in the US?
Hantavirus
What is the common name for a Coccidiomycosis infection?
Valley fever
What is the most common normal flora to cause infection in the upper and lower respiratory tract?
Staphylococcus
What human body system is involved in the majority of hospital acquired infections?
Urinary
What factors contribute to the trends of emerging diseases?
Global travel, war, lack of vaccination
Lipid A is what type of toxin?
Endotoxin
An accumulation of bacteria residing on a surface is known as?
Biofilm
The protein coat that surrounds the nucleic acid core of a virion is called the ____
capsid
how many types of virions exist?
2
The type of viral structure that involves coiling of the capsid and nucleic acid core is ____
helical symmetry
The largest family of viruses to infect humans is ____
Herpesviridae
The most stable form of a virus is ____
double stranded DNA
(eg. Herpesviridae)
What happens to the virus-infected cell in a lysogenic infection?
the viral genome becomes part of the cell’s DNA
What are viral envelopes?
pieces of the host cell’s plasma membrane
The least stable form of a virus with the highest mutation rate is ____
single stranded RNA
(eg. Ebola)
Air, food, and insects are considered to be ____
transmission mechanisms
the process of assembling the virion in the host cell is known as ____
maturation
Floral variegation is a result of infection by ____
viruses
(plants = variegation)
“Oriental” sore is the common name for the disease ____
Leishmaniasis
Acute African sleeping sickness is fatal because it infects the ____
brain
What is the inactivated poliovirus vaccine?
Salk
Rice water stools are associated with ____
cholera (vibrio cholerae)
Rotavirus infection are dangerous in infants and toddlers because of ____
rapid dehydration
What arbovirus is also known as “Breakbone Fever?”
Dengue Hemorrhagic fever
African sleeping sickness is spreading of the bile by ____
tsetse fly
The annual influenza season is an example of ____
antigenic drift
The most common vector in the arboviruses is the ____
mosquito
microbes that infect the genitourinary tract are sometimes referred to as ____
sexually transmitted diseases
what are 3 potential reservoirs of pathogens?
animals, humans & non-living surfaces
clostridia species produce some of the deadliest of the ____
neurotoxins
enterotoxins work by damaging the lining of the ____
intestines
which of the following types of epidemics is over more quickly: common source or propagated
common source
lipid A is an ____
endotoxin
direct damage to the host is controlled by ____
the immune response
hemolysins are ____ that ____
exotoxins
destroy WBCs and RBCs
endotoxins are released from dead ____ bacteria in the form of ____
gram-
lipid A
what genus of bacteria have mycolic acid in their cell walls?
mycobacterium
what disease may present with a pseudomembrane composed of bacteria fibrin and cell debris?
diphtheria
lipid A elicits…
a strong immune response
patient zero is most commonly associated with ____
propagated epidemic disease
