Infection control MCQs

Question 3 1 / 1 pts Which patient might you put in a negative pressure room? A patient with measles A patient with 3rd degree burns A patient with meningococcal meningitis A patient with a kidney transplant

A patient with measles Infections that put OTHERS at risk due to aerosols require a negative pressure room (keeps the causative agent from 'escaping' into the hospital environment). Measles virus is transmitted through aerosols, and is one of the few organisms requiring aerosol precautions. When the patient needs protection from infections (e.g. b and d), a positive-pressure environment is used (keep pathogens OUT). Meningococcal meningitis requires droplet precautions, which do not include isolation in a negative-pressure room.

Question 7 1 / 1 pts A patient in the ICU develops diarrhea after several days of treatment with a broad-spectrum antibiotic for a severe infection. The causative agent is found to be a Gram-positive, strictly anaerobic bacterial rod that is known to cause this type of infection. Which of the following interventions will help to prevent transmission of this pathogen to others? Cleaning a toilet with an isopropanol-based cleaner HEPA-filtering room air Autoclaving bed linens Using hand sanitizer Treating all surfaces with benzalkonium chloride

Autoclaving bed linens Referring to Clostridium difficile (Gram + anaerobe related to those producing botulinum and tetanus toxins). Efficient killing of endospores requires either a high-level disinfectant, such as bleach (sodium hypochlorite solution), or sterilization. Transmission is by contact, so filtering air will not be effective in preventing transmission. Quaternary ammonium compounds (b) and alcohols (c, e) are low and intermediate-level disinfectants, respectively, so will not be effective against the endospore form of the organism.

Question 2 1 / 1 pts A 16-year-old boy is brought to the emergency department after a car accident. He has multiple contusions, broken bones, and burns to the upper torso. What method of decontamination would be best to treat a stethoscope (in normal cases a non-critical piece of equipment) being used on this patient? Ethylene oxide 70% alcohol Chlorhexidine Benzalkonium chloride Iodophor

Ethylene oxide The skin is compromised in this patient, necessitating a higher level of decontamination than would normally be the case. By the way, you shouldn't autoclave a stethoscope if you want to use it again. In practice, this would be a situation for a disposable stethoscope. Did you know that nurses clean their stethoscopes more often than physicians and medical students? Something to think about...

Question 8 1 / 1 pts A 63-year-old woman is being artificially ventilated after ingestion of botulinum toxin from improperly canned tomatoes. She was healthy prior to this incident. Three days after intubation, the patient develops a respiratory infection. What terminology best describes the type of infection, and what is the most likely causative agent? Hospital acquired, Pseudomonas aeruginosa Hospital acquired; Legionella pneumophila Community acquired; Legionella pneumophila Community acquired; Pseudomonas aeruginosa Community acquired; Enterococcus faecalis Hospital acquired, Enterococcus faecalis

Hospital acquired, Pseudomonas aeruginosa Be sure to consider the time frame, which tells you it is a nosocomial or hospital-acquired infection, and then the most likely causative agents of nosocomial pneumonias (in the handout notes).

Question 9 1 / 1 pts Why on earth are rates of hand hygiene compliance so low? (Select all that apply.) I can't say, but I will always comply with hand hygiene recommendations! I'll tell you what I think about this sometime, but I will always comply with hand hygiene recommendations!

I can't say, but I will always comply with hand hygiene recommendations! I'll tell you what I think about this sometime, but I will always comply with hand hygiene recommendations! Thanks for the promise :).

Question 5 1 / 1 pts A 45-year-old government virologist has been accidentally exposed to smallpox virus after a breach in a secure level 4 laboratory. Which precaution, not part of the standard precaution protocol, would be applied during the observation and treatment of this patient? Hand sanitizing before and after patient contact Bathing of the patient in ethylene oxide Masks within 3 feet of the patient Isolation in a room with reduced pressure Bathing of the patient in benzalkonium chloride

Isolation in a room with reduced pressure Smallpox requires aerosol precautions. One of these is use of a negative-pressure room for isolation. Any bathing protocol would be more effective in preventing transmission by contact, and bathing in ethylene oxide would NOT be a good idea or particulary easy to do (it's a highly toxic gas...). Masking within 3 ft. is suffcient for pathogens transmitted by droplet, but not aerosols. Hand sanitizing is part of the standard protocol, so this is ruled out by the question (although you would definitely do it).

Question 11 1 / 1 pts A 30-year-old man presents to his physician with a dry cough, fever and headache. He admitted to having the cough for over a week. Chest X-ray showed infiltrates but no consolidation. The physician suspected infection with a small, wall-less bacterium. What precaution should be taken with this patient? Mask within 3 ft of patient Use of N-95 respiratory mask Admit patient to hospital Dedicated equipment for the patient Sterilizing all equipment used on the patient

Mask within 3 ft of patient Mycoplasma pneumoniae is one of the few bacteria with no cell wall, and causes a pneumonia characterized by dry cough and interstitial infiltrates (you'll learn more about this in the respiratory 2 module). It is readily transmissible in droplets, and as such droplet precautions are recommended by the CDC.

Question 4 1 / 1 pts A 45-year-old man presentes with fever. He had been discharged from hospital the previous day. The fever was found to have been triggered by a bacterial infection. Which of the following is the most appropriate description of this infection? Nosocomial Exogenous Community-acquired Endogenous

Nosocomial The timeframe between admission/discharge and emergence of symptoms is used as a rule of thumb in determining whether an infection is considered hospital- or community-acquired. The reason is the incubation time between transmission/acquisition of the pathogen and when symptoms are noted. However, realize that some infections can take weeks or months to present, so these wouldn't fall into this 48h timeframe. Endogenous and exogenous refer to the source of the infection—there isn't enough information here to determine this.

Question 10 1 / 1 pts An infection control committee is discussing protocols related to infections caused by a particular virus. The infectious disease fellow points out that this virus is resistant to many disinfectants, including alcohol and quaternary ammonium compounds. To what family does the virus in question most likely belong? Picornaviridae Flaviviridae Retroviridae Herpesviridae Paramyxoviridae

Picornaviridae These disinfectants affect enveloped viruses (their membranes make them susceptible; how does each type affect lipid bilayers?). Among the families listed, only herpesviruses are enveloped.

What precautions are required, according to the CDC, when seeing an antibiotic-susceptible pneumococcal pneumonia patient? Aerosol Droplet More than one of the above Standard Contact

Standard Pneumococcal pneumonia does not require special precautions beyond standard according to the CDC (it is not readily transmissible), but droplet precautions are used in some institutions.

Question 6 1 / 1 pts An isolate submitted for susceptibility testing is reported to be resistant to erythromycin, gentamycin, and tetracycline. If this isolate is most likely to be Escherichia coli, what type of precautions should be taken in a health-care setting? Standard only Standard plus contact Standard plus aerosol Standard plus contact plus droplet Standard plus droplet

Standard plus contact Antibiotic-resistant organisms require contact precautions, even when the causative agent itself might not. In this case, the causative agent is most likely E. coli, which does not have any particular associated precautions beyond standard. But the fact that it is resistant to antibiotics to which it should be susceptible make it different than "regular" E. coli that is in everyone anyways, and thus preventing transmission becomes more important.

Question 12 1 / 1 pts What is the most correct term for treating a liquid at 135˚C for 2 s? Sterilizing Ultrafiltration Pasteurization Autoclaving Ultrapasteurization

Ultrapasteurization Ultrapasteurization is also know as UHT (ultra-high temperature) pasteurization. The higher temperature used permits a much shorter contact time with the product, and is more efficient in reducing bacterial numbers as compared to traditional pasteurization. While they are not sterile, these reduced numbers permit a much longer shelf-life than pasteurization, especially coupled with aseptic (i.e. sterile) packaging processes.