Emerging Infections

Question 0

What are new pathogens?

Answer 0

Includes new species and new strains of existing species

e.g. SARS-CoV, H1N1 influenza (pandemic strain)

Question 1

What are emerging infections?

Answer 1

New pathogens
Re-emerging infections
drug resistant
Nosocomial
Zoonotic
bioweapons

Question 2

What are re-emerging infections?

Answer 2

Have experienced increased incidence following a period of recession or control of infection in a given area
e.g. Poliomyelitis or malaria

Question 3

What are some examples of re-emerging infections?

Answer 3

MRSA, VRSA
Multidrug resistant tuberculosis
HIV
Influenza A
N. gonorrhoea

Question 4

What is the definition of outbreak?

Answer 4

A sudden unexpected increase in disease incidence

Question 5

What is the definition of epidemic?

Answer 5

A greater prevalence of disease in a population/community than is generally expected in that population at a given time

Question 6

What is the definition of pandemic?

Answer 6

A greater worldwide prevalence of disease than expected at a given time

Question 7

What is the definition of endemic?

Answer 7

refers to a pathogen having a steady prevalence in a given population, area, or community

Question 8

What are nosocomial infections?

Answer 8

An infection acquired by a patient admitted to hospital/health care facility for a reason other than the infection
Infection was not present or incubating in the patient before admittance
signs of infection may appear after discharge
Often opportunistic

Question 9

What are factors associated with incidence of nosocomial infections?

Answer 9

Increased prevalence of pathogen and close contact in hospital setting
decreased immune status in infected population
emergence of antibiotic-resistant strains of pathogen
surgery or devices

Question 10

What are some examples of nosocomial infections?

Answer 10

S. aureus
MRSA/VRSA
Candida albicans
C. difficile
UTI
Hospital acquired pneumonia
Surgical site infection
Viruses

Question 11

What are Zoonotic infection?

Answer 11

An infection that is transmitted to a human from another species
May or may not be contagious
e.g rabies

Question 12

What are factors associated with incidence of zoonotic infections?

Answer 12

Increased prevalence of vector in changing climates, increased interactions
Increased prevalence of pathogen in developing areas, loss of natural habitat
Human activity - increased transportation, dmas, deforestation
Complex interactions between environment, vector, and host (7 generations)

Question 13

What are the at risk groups for zoonotic infections?

Answer 13

Occupational risk (butchers, farmers etc)
Activity (camping, swimming)
Animal scratches/bites (rabies, arboviruses)

Question 14

What are some examples of zoonotic infections?

* You should be able to define the vector for a disease for the final

Answer 14

Flavivirus
Rabies
SARS CoV
Influenza A
Yersinia pestis
Plasmodium falciparum

Question 15

What is the machupo virus spread by?

Answer 15

Bolivian hemorrhagic fever
Large vesper mouse, machupo virus harmless persistent infection in bush mice
DDT leads to shortage to cats = more mice = mice invade human dwellings

Question 16

What are bioweapons?

Answer 16

May involve pathogens with limited or no current prevalence

Historic and contemporary usage: smallpox, anthrax

Question 17

What are category B criteria for bioweapons?

Answer 17

Are moderately easy to disseminate
result in moderate morbidity rates and low mortality rates
require specific enhancements of CDCs diagnositc capacity and enhanced disease surveillance

Question 18

What are category C bioweapons?

Answer 18

easily available
easy to produce and disseminate
high mortality and high morbidity

Question 19

What are device associated infections?

Answer 19

Are generally nosocomial
Are associated with a number of opportunistic pathogens
includes catheters, shunts, prostheses
plastic devices are prone to colonization by bacteria, biofilm formation
Symptoms related to site of infection, sepsis always a risk

Question 20

What are the symptoms related to intravasular catheters?

Answer 20

Pain, inflammation, erythema, purulent discharge at exit site, low-grade fever
Diagnosis via analysis of exit site swab

Question 21

What are the symptoms related to ambulatory peritoneal dialysis catheters?

Answer 21

Pain, inflammation, erythema, purulent d/c
Peritonitis w/ abdominal pain, fever, nausea, vomiting
Tachychardia, increased WBC in dialysis fluid
Diagnosis via analysis of exit site swab or dialysis fluid

Question 22

What are the symptoms of a urinary catheter infection?

Answer 22

flank pain, pressure or spasm near the bladder, hematuria, cloudy urine, fever
Diagnosis via urinalysis via catheter
- Any bacterial numbers are considered significant when sample is taken via catheter
- No introduction of bacteria from the urinary tract

Question 23

What are the symptoms of prosthetic joint infection?

*Important because joints can only be replaced so many times, preventative antibiotics

Answer 23

Joint/bone pain, tenderness, inflammation, fever
Loosing of prosthetic joint, low grade bacteremia
Chronic infection - requires removal of the prosthesis
Diagnosis via analysis of joint aspirate: Culture, stain, PCR (pathogen associated gene), CRP, erythrocyte sedimentation rate, elevated leukocytes, sinus tract formation

Question 24

What are the symptoms of CSF shunt infection?

Answer 24

Symptoms appear months to years after surgery
Ventriculoatrial (VA) shunt infections - fever, tachycardia, rigors, rash, arthralgia, anemia, myalgia
Ventriculoperitoneal (VP) shunt - vomiting, headache, visual disturbance, abdominal distension

Question 25

What benefits do the use of microbes have for a host?

Answer 25

Increase immune capacity
Compete with pathogenic organisms/microbes
Target pathogenic organisms/microbes

Question 26

What are preventative/therapeutic approaches of microbiology?

Answer 26

Probiotics
Prebiotics
Synbiotics

Question 27

What are emerging therapeutic microbiology approaches?

Answer 27

Bacteriophage

Fecal transplantation

Question 28

What are probiotics used for?

Answer 28

Gastrointestinal disorders
Genito-urinary tract infections
Skin

Question 29

What is the function of host microbiome?

Answer 29

Provides a delicate balance between health and disease

• use of probiotics long term immune stimulation, good or bad?
• proinflammatory treatments vs. anti-inflammatory treatments indications and CIs

Question 30

What are prebiotics/synbiotics?

Answer 30

Are nonliving non digestible factors that contribute to the growth of probiotics

Question 31

What is phage therapy?

Answer 31

Using bacteriophages as antibiotics