Lecture 16

Question 1

Hand Washing History, what was happening? Who is the father of modern Handwashing?

Answer 1

• Women who were attended by physicians during childbirth had a 10-35% chance of contracting infections and dying.
• Meanwhile, women who were attended by midwives had a much less disease incidence and mortality rate.
• In 1847, Semmelweis hypothesized that the physicians were attending women after performing autopsies without cleansing their hands. He ordered the physician interns to wash their hands with a chloride and lime solution before attending to the women.
• Mortality fell to about 1-2% afterwards.

Question 2

What is infection prevention? Who works in this field?

Answer 2

• A field that focuses on the prevention of the spread of infections in a healthcare setting.
• Use published guidelines to promote new policies, initiatives, and interventions to prevent infection.
• Work closely with healthcare workers as well as the county and state health departments to mitigate risks to patients, employees, and visitors.
• Infection preventionist, Clinical Data Analysts, Hospital Epidemiologist.

Question 3

What do they do?

Answer 3

• Control and prevent hospital acquired infections.
• Track current infections in the hospital to determine infection rates.
• Report infections to the county, state, and/or CDC.
• Perform outbreak investigations.
• Develop programs and initiatives to stop the spread of infection.
• Ensure hand hygiene compliance.
• Educate and collaborate with healthcare workers.
• Ensure proper sterilization and disinfection protocols are followed.

Question 4

What infections are reported to the County, State, and/or CDC? What is done with this information?

Answer 4

• Certain communicable diseases must be reported to the county health department which gets reported to the state (ex. Hepatitis, Chlamydia, Gonorrhea)
• This information is used to determine if there is an outbreak or epidemic occurring.
• Ensure infection prevention initiatives are working or determine if more needs to be done.
• Aids in epidemiological research efforts.
• Used for surveillance at the state and national level.

Question 5

Why is hand hygiene compliance important? What are hospitals doing to monitor hand hygiene?

Answer 5

• Hand hygiene is most important method to prevent the spread of infection in a healthcare setting.
• Many hospital acquired infections are spread due to poor hand hygiene compliance.
• UofM implement ways to monitor hand hygiene compliance (covert observers).

Question 6

Why is routine surveillence done? In what ways is the data used?

Answer 6

• Routine surveillance is done to determine how may infections each unit of the hospital has.
• This is used to compare infection rates to other similar hospitals using data from the CDC.
• Determines if there is an outbreak occuring.
• Determines if current infection prevention measures are working or if more needs to be done.

Question 7

1) What is disinfection?
2) What is sterilization?

Answer 7

1) Disinfection is the use of chemical means to kill pathogenic microorganisms, but not endospores.
- Low level: items that come into contact with the skin, kills some viruses and bacteria.
- Intermediate level: items that come in contact with skin. Kills vegetative bacteria, most viruses, and most fungi.
- High level: Items that contact mucous membranes. Kills all microorganisms in or on an instrument, except for small numbers of bacterial sports.
2) Sterilization is the use of chemicals, heat, or pressure to completely destroy all microbial life, including endospores. Used for items that come in contact with sterile body parts or blood.

Question 8

Step 1: Establish existence of an outbreak

Answer 8

• An increase in the number of cases that are expected for that population.
• Many more students than usual are going to UHS and UM emergency. This should be a red flag.

Question 9

Step 2: Verify the Diagnosis

Answer 9

• Understand what the microbiological cluprit of the outbreak is by collecting lab reports and clinical specimen.
• Lab testing determined that norovirus was the culprit of the UofM outbreak.

Question 10

What is norovirus?

Answer 10

• It is a non-enveloped virus.
• Incubation time of 12-48 hours.
• Symptoms last 1-3 days
• Spread through the vomit and feces of an infected person. Can be transmitted from hands to mouth after interacting with environment or from sharing utensils with an infected person.

Question 11

Step 3: Create a Case Definition

Answer 11

• Who, What, When, Where
• The individuals who fit this case will be included into the outbreak investigation.

Question 12

Step 4: Find all cases and create a list

Answer 12

• Now the case definition is clear, information from individuals who are part of the outbreak should be collected.
• Information such as demographic information, onset of symptoms, types of symptoms, can help the public health officials determine the source of the outbreak and how to effectively control it.

Question 13

Step 5: Perform Descriptive Epidemiology

Answer 13

• Create an epidemiological curve (visual display of the number of cases during an outbreak over time.
• Aids in determining magnitude and type of outbreak.
• Continuous, propagated, person-to-person, intermittent

Question 14

Step 6: Develop Hypothesis

Answer 14

• Using the information from the case list and the epi curve, develop a hypothesis of type of outbreak, onset of outbreak, and epicenter.
• Ex: Determine the outbreak started and spread in South Quad and West Quad.
• Person-to-person or propagated is most likely what spread norovirus.

Question 15

Step 7: Evaluate Hypothesis

Answer 15

• Use epidemiological study designs to determine if your hypothesis is valid.
• Case control study: Compare those who got infected and who did not with the hypothesized risk.
• Cohort Study: Compare the hypothesized risk of getting infected to those who actually did or did not get infected.

Question 16

Step 8: Implement Control Measures

Answer 16

• To prevent any further spread of infection, protocols are put into place to disinfect, quarantine, and rectify the situation.
• Urged students to stay home.
• Developed a way to ensure meals got to those students so they weren’t going to the dining halls.
• Disseminated information about the importance of hand washing.
• Thoroughly cleaned south quad.

Question 17

Step 9: Communicate Findings

Answer 17

• Inform the public and media of outbreak.
• Share information about process, hypothesis, and outcome.
• Consider publishing findings in scientific journal.
• Could aid in a future outbreak investigation.

Question 18

Step 10: Continue Surveillance

Answer 18

• Continue monitoring for new cases.
• Ensure the control measures are working to stop outbreak.
• Re-evaluate control measures and hypothesis if outbreak is continuing.

Question 19

What are some healthcare associated infections?

Answer 19

GI infections, Pneumonia, Surgical site infection, central line associated blood stream infection, UTIs.

Question 20

1) Describe S. aureus
2) How prevalent is S. aureus?

Answer 20

1) Gram-positive coccus. Grows as single cells, in pairs, in tetrads, and in grape-like clusters. Colonies on agar plates are yellow-gold color. b-hemolytic on blood agar.
2) Present in the noses and on the skin of 30% of the U.S. population.
- Able to colonize and infect healthy, immunologically competent people.
- One of the most common and most important G-positive hospital acquired infections.
- Most common cause of skin and soft-tissue infections reported worldwide.

Question 21

Antibiotic resistance in S. aureus

Answer 21

• Methicillin-resistant strains have arisen and flourished since the 1970s.
• Resistant to the penicillinase-stable penicillins.
• These strains carry the mecA gene, which encodes a penicillin binding protein.
• They are called methicillin resistant Staphylococcus aureus (MRSA)
• Resistant to all b-lactum antibiotics. 1.5% of U.S. population carries MRSA.

Question 22

Describe C. difficile

1) How is it transmitted?

Answer 22

• Gram + bacillus
• Opportunistic organisms
• Anaerobic
• Infects the GI system
• Spore Forming (biggest reason for virulence)
• Diarrhea, fever, and abdominal cramping.
  1) Transmitted through the feces of an infected person. Spores that are produced can persist on surfaces for up to two years. The spores can be transferred from environment to patient or from the hands of a healthcare worker to patient.

Question 23

1) What is a primary cause of C. diff contraction in hospital settings?
2) How is C. diff prevented?

Answer 23

1) Common in healthcare environment, for use of antibiotics to be used for a prolonged amound of time or when they are not necessary can have adverse effects on the natural gut flora of an individual. This leaves room for C. diff to take hold and cause an infection. Produces virulence factors, Toxin A and B, that damage the intestinal mucosa.
2) The spores are impervious to most cleaners, such as bleach or hydrogen peroxide must be used to effectively clean rooms of C. diff patients. Appropriate use of antibiotics. Hand sanitizer will not remove spores from hands, washing with soap and water is the only way of properly cleanse hands after interacting with a C. diff patient.