2. What is MRSA?
Staphylococcus aureus or “Staph” bacteria that commonly
lives on the skin and in noses of healthy people.
usually staph bacteria are harmless
staph bacteria may cause an infection
If they enter the body through a break in skin
infections can usually be treated with antibiotics
3. What is MRSA?
MRSA: Methicillin-Resistant Staphylococcus aureus
MRSA is a type of staph bacteria that has become
resistant to methicillin and many other antibiotics
traditionally used against S. aureus.
They can range from very minor to life-threatening
They live on surfaces for several days
4. Basic characteristic of S.aureus
Gram positive
Non-motile
Spherical clusters (clumps of grapes)
Golden color, purple on stain
Hemolytic on blood agar
Produces coagulase and catalase
enzymes
5. Virulence factors: avoiding host defensive
mechanism
Cell wall
Cytoplasmic membrane-osmotic barrier prevents disequilibrium
of ionic content. Preventing cell osmotic instability and
susceptibility to lysis
Polysaccharide capsule-slime layer; adhesion, inhibits
phagocytosis
Peptidoglycan allows bacteria to attach to host’s cell membranes.
6. History of S. aureus resistance
1941 Introduction of penicillin into treatment of infectious diseases
1944 S.aureus penicillin resistant
1960 new Penicillinase-resistant drugs used to fight Staph. e.g. Methicillin
1975 Methicillin resistance strains of S.aureus emerge
1988 2.4 % S.aureus are methicillin resistance
1989 3% Enterococcus Vancomycin resistant (VRE)
1991 29% S.aureus methicillin-resistance
1993 7.9 % VRE
1996 S.aureus strain intermediate Vancomycin-resistance
1998 Man in N.Y dies from S.aureus
2000’s CA-MRSA emerged (USA reported 300 cases)
7. What are the infection with MRSA ?
Most commonly: skin infections (including
SSI), soft tissue (necrotizing fasciitis)
Bacteremia, infective endocarditis –sever
Pneumonia (rare cases)
Bone & joint: Osteomyelitis, Septic Arthritis,
Device-related)
CNS (meningitis, brain abscesses)- sever
8. How does MRSA spread?
Through direct contact with the skin of carrier, personal items of carrier, objects
of MRSA
Responsible for 94,000 life threatening infections and 18,650 deaths in 2005
(more than AIDS)
2 – 10% population colonized with MRSA
9. Column %
Pathogen
CLABSI
11,428
CAUTI
9,377
VAP
5,960
SSI
7,025
Total*
33,848
CoNS 34 3 1 14 15
S. aureus 10 2 24 30 14
Enterococcus spp. 15 15 1 11 12
Candida spp. 12 21 <1 2 11
E. coli 3 22 5 10 10
P. aeruginosa 3 10 16 5 8
K. pneumoniae 5 8 7 3 6
Enterobacter spp. 4 4 8 4 5
A. baumannii 2 1 8 1 3
Distribution and Rank Order of 9 Most Common Pathogens Reported
for 28,502 HAIs, NHSN 2006-2007
15.6% of healthcare-associated infections had >1 pathogen (polymicrobial)
*
Hidron et al. Infect Control Hosp Epidemiol 2008;29:996-1011
10. Who is at risk for MRSA?
ANYONE …..can get MRSA
Those most at risk;
Spend vast time in crowded places (hospitals, schools, dorms,
military, native populations)
Share sports equipment
Share personal hyiegene items
Play contact sports
Overuse or misuse Antibiotics
Age > 65 years
11. Can healthy people get MRSA?
25 – 30% population is
colonized in the nose
with MSSA at a given
time of ≥ 3 mon.
12. Can healthy people get MRSA?
Play contact sports
43% of all skin
infections are the
result of one strain of
MRSA
19. Can healthy people get MRSA?
YES
Community-Associated MRSA (CA-MRSA) has
been reported among: athletes, prisoners, and
military recruits.
Outbreaks: schools, gyms, day care centers and
HIV.
CA-MRSA has been found in cats and dogs and
possibly reinfect the pet owners.
20. The antibiotic resistance
Why: How:
Unnecessary antibiotic use
Antibiotics in food and water
Germ mutation: Antibiotics
don’t destroy every germ they
target. mutate much more
quickly than new drugs can
be produced.
Transfer factors: survival of
the fittest-quantum
communication
Presence of mec gene in the
bacteria
It alters the site at which
methicillin binds to kill the
organism
As a result methicillin and
other antibiotics can not bind
to bacteria.
21. CA-MRSA Vs. HA-MRSA
CA – MRSA HA – MRSA
Spreads more easily
Cause more skin diseases
Susceptible to Clindamycin,
tetracycline, bactrim
Common in USA ( USA 300)
known resistance to most
antibiotics
Has virulence factors (necrotizing
pneumonia, skin, soft tissue
infections)
Hospitals can encounter CA-MRSA
as well.
More resistant to Antibiotics
Less mobile
Transmitted :
direct contact
fluids
procedures
Indirect contacts
22. Risk factors for acquiring HA-MRSA
Break in natural skin barrier.
surgery (especially implants)
bedsores
Invasive contaminated devices and procedures
IV catheters
Urinary catheters
Intubation
Overuse of Antibiotics (combination in prophylaxis
management)
Patients with comorbidities
23. Colonization Vs. infection
S. aureus colonization
on/in body without illness
0.9 – 13.2% health care workers are colonized
25 – 30% are colonized in nose at a given time ~ ≥ 3 months
S. Aureus infection
once colonized > 3 months and infects, becomes difficult to treat.
30 – 60% colonized patients risk of infection
Host factors influence the onset of infection, e.g. immunosupression,
steroids, DM, invasive devices, surgery, skin breakdown, PNA,
obesity, hematoma.
32. Modeled Incidence and Percent Change for All Invasive Hospital-Onset
and Healthcare-Associated, Community-Onset MRSA infections, 2005-
2007
Year Modeled
incidence per
100,000
population
Modeled
percent
change from
previous year
Total modeled
percent
change
P-value
Hospital-onset
2005 9.95
2006 8.96 -9.97%
2007 8.24 -8.08% -17.2% 0.01
Healthcare-associated, community-onset
2005 22.13
2006 21.11 -4.59%
2007 19.70 -6.71% -11.0% 0.04
Kallen AJ, et al, SHEA 2009, Abstract 49
33.
34. How can MRSA be prevented?
Wash hands
Personal items
Wounds clean and covered
Shower after athletic games and practices
Sanitize linens
Use antibiotics appropriately and safely
35. Researches and data:
75% of MRSA are CA-MRSA
Responsible for 94,000 life threatening infections and 18,650 deaths in 2005
(more than AIDS)
New lethal strain emerges: 50% cases death among MRSA 600 (Henry ford
hospital, Florida, USA-2007)
Ordinarily 11% of patients infected with MRSA die in 30 days without
controlled management and presence of factors (age > 64, untreated, or
complications)
37. Treatment
The management of all MRSA infections should include:
Identification
Elimination
and/or Debridement
of the primary source
38. Outpatient management of skin and
soft tissue infections in CA-MRSA
signs/symptoms of skin
infection:
•redness
Swelling•
Warmth
Pain/tenderness•
Complaint of ”spider bite”
With lesion purulent
Fluctuance-palpable
•Yellow or white center•
Central point or “head”
Draining pus
If systemic symptoms, severe
local symptoms,
immunosupression, or failure to
respond to I&D
Provide antimicrobial therapy
with coverage for
Streptococcus spp.
Consider adding coverage for
MRSA (if not provided initially)
Maintain close follow-up
43. Decolonization treatment (1)
1. Use small mupirocin tube each time you apply
to your nose (about 1/2 of the small tube to each
nostril).
2. Apply a pea-sized amount of mupirocin nasal
ointment inside each nostril. Use a clean finger or
a Q-tip to apply
3. Press your nostrils together and massage for
about 1 minute.
4. Avoid contact with your eyes as this could cause
irritation.
5. If some medicine gets into your eyes, rinse them
thoroughly with cool water
6. Apply the nasal ointment twice daily for 5 days.
7. Do not use any other topical nasal medications
for the 5 days of treatment.
44. Decolonization treatment (2)
Method of application
Shower or bathe with Hibiscrab ® for each day that
you use the nasal ointment using a freshly laundered
wash cloth and towel each time
Ensure all skin surfaces are well covered when using
the body wash.
Shampoo your hair with regular shampoo first,
ensure that hair and body are wet.
Use 2 packets water wash for each shower or bath.
Each packet contains about 1 tablespoon of the soap
Apply the Hibiscrab ® as you would any other liquid
soap . Leave the soap on your skin for 1-2 minutes.
Apply lotion all over hair and body, paying special
attention to armpits groin and feet.
Rinse completely after the shower or bath.
Avoid contact of the soap with your eyes as it cause
irritation
Dry with a clean, dry towel.
Discard all empty packages in your regular garbage.
After each shower put on clean clothes and sleep on
freshly laundered sheets Ensure all bed linen and
towels are changed daily and washed on the highest
possible temperature.
Hibiscrab ® (4% chlorhexidine) soap
shower / bath
45. In conclusion ……..
MRSA is increasing in the community and in Hospitals
Over use of antibiotics has created some of the problem
Resistance among species is evolving
Close quarters, equipment, environment and
contaminated hands are sources for transmission
Limited antibiotics available to treat MRSA
Pre-surgical screening program is an effective method of
detection for treatment and precautions
1) This slide summarizes the percent distribution and rank order of the 9 most common pathogens (which are listed in the first column), by healthcare-associated infection (HAI) type.
2) The distribution for all HAI types combined is listed in the far right column, where 33,848 pathogens are represented. It is important to note that 15.6% of the HAIs had more than one pathogen reported, and therefore the total number of pathogens is greater than the total number of HAIs
3) The most frequent pathogen in each column is in yellow, the second most frequent is in blue, and the third most frequent in green
4) Overall, Coagulase-negative Staphylococci, Staphylococcus aureus, and Enterococcus were the most frequently reported pathogens associated with any type of HAI, although this ranking differed by HAI Type.
5) Of note, Enterococcus and S. aureus were among the three most frequently reported pathogens in at least 3 of the 4 HAI types.
Data from CDC’s Emerging Infection Program/Active bacterial Core Surveillance MRSA project also has suggests a fall in invasive MRSA infections at the nine sites in the United States. From 2005 to 2007, hospital-onset invasive MRSA infections fell 17% while community-onset invasive MRSA infections among people with healthcare exposure fell 11%
Contributed by Jorge P. Parada, MD, MPH, FACP, FIDSA, Prof. of Medicine, Stritch School of Medicine Loyola University Chicago