MICROBES UNDERCOVER
A microorganism capable of producing disease is called a ________.
Pathogen
Name ONE disease caused by a prion.
Creutzfeldt-Jakob disease (CJD), fatal insomnia, OR Kuru
Tuberculosis, bacterial pneumonia, the common cold and influenza are examples of infections that may be transmitted by ________.
Inhalation
The stage in which a pathogen is replicating but the host has no recognizable symptoms is the ________ period.
Incubation period
Which organism is a Gram-positive coccus commonly spread by direct contact and can cause skin infections, pneumonia, heart valve infections and bone infections?
A. E. coli
B. Staphylococcus aureus
C. C. difficile
D. Salmonella
B. Staphylococcus aureus
What is virulence?
The ability of a microorganism to cause disease.
Bacteria that are spherical are called ________, while elongated bacteria are called ________.
Cocci; bacilli
A patient develops an infection after spores enter a contaminated puncture wound. Which mode of transmission occurred?
A. Ingestion
B. Direct contact
C. Penetration
D. Inhalation
C. Penetration
Which stage of infectious disease is associated with initial vague symptoms such as fatigue, fever or feeling unwell?
A. Incubation
B. Prodromal
C. Acute
D. Resolution
B. Prodromal
A patient recently received antibiotics and now develops watery diarrhea and abdominal cramping. The suspected organism is ________.
Clostridium difficile
A patient develops an infection while receiving treatment in the hospital. This infection would be described as:
A. Iatrogenic
B. Nosocomial
C. Opportunistic
D. Fulminant
B. Nosocomial
Nosocomial means hospital-acquired or health-care associated. Iatrogenic refers to illness caused by a medical procedure or treatment.
Which pathogen contains no DNA or RNA?
A. Virus
B. Bacterium
C. Prion
D. Fungus
C. Prion
Prions are infectious protein particles that contain no DNA or RNA and cause protein misfolding.
Give TWO examples of diseases transmitted through ingestion.
Put the stages of infectious disease in the correct order:
Acute → Infection → Resolution → Prodromal → Incubation → Convalescent
Infection → Incubation → Prodromal → Acute → Convalescent → Resolution
A patient presents after a contaminated wound with:
The bacterial exotoxin blocks the release of inhibitory neurotransmitters, resulting in unopposed muscle stimulation.
Identify the organism.
Clostridium tetani (tetanus)
The organism is a Gram-positive anaerobic spore-forming bacillus, and the lecture highlights the spatula test as a distinctive diagnostic feature.
What is the difference between incidence and prevalence?
Incidence = number of new cases occurring in a defined population over a defined period of time.
Prevalence = number of active cases at a given time.
Give ONE major difference between viruses and bacteria regarding replication.
Bacteria can replicate on their own, whereas viruses are obligate intracellular pathogens and cannot replicate outside of a living cell.
What is vertical transmission, and give ONE example from the lecture.
Transmission from mother to baby, including across the placenta or during birth.
Examples include HIV or chickenpox.
Name THREE systemic manifestations that are commonly expected with an infectious disease.
A patient presents with:
Stool culture identifies E. coli O157:H7.
Should this patient routinely receive antibiotics?
NO!!!!!!!!!
Treatment is supportive care; antibiotics are NOT recommended
A newly emerging infection has an R₀ of 2.5.
What does this mean, and what would you predict about the infection's ability to spread?
One infected person causes an average of 2.5 new infections in a completely susceptible population. Because R₀ > 1, the disease can spread and may cause an outbreak or epidemic.
This microorganism:
What microorganism is being described?
Rickettsia
A patient develops:
The infection occurred after a tick bite.
Identify the disease AND its mode of transmission.
Lyme disease; penetration via a tick bite.
It is caused by Borrelia burgdorferi, a spirochete that the lecture notes is neither Gram-positive nor Gram-negative
A patient presents with:
The responsible bacteria produced toxins acting as superantigens, causing massive T-cell activation and cytokine production. What syndrome should you suspect?
Toxic shock syndrome (TSS)
A virus:
A. Identify the virus.
B. Name ONE opportunistic infection from the lecture that may occur with severe immunodeficiency.
C. What is the treatment?
A. HIV
B. Pneumocystis jirovecii pneumonia (PJP/PCP)
C. Antiretroviral drugs; treatment is not a cure.