* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download BAD BUGS Healthcare Workers and Emerging Antibiotic
Childhood immunizations in the United States wikipedia , lookup
Traveler's diarrhea wikipedia , lookup
Hygiene hypothesis wikipedia , lookup
Hepatitis C wikipedia , lookup
Hepatitis B wikipedia , lookup
Gastroenteritis wikipedia , lookup
Common cold wikipedia , lookup
Marburg virus disease wikipedia , lookup
Carbapenem-resistant enterobacteriaceae wikipedia , lookup
Urinary tract infection wikipedia , lookup
Transmission (medicine) wikipedia , lookup
Sociality and disease transmission wikipedia , lookup
Anaerobic infection wikipedia , lookup
Neonatal infection wikipedia , lookup
Clostridium difficile infection wikipedia , lookup
Staphylococcus aureus wikipedia , lookup
Infection control wikipedia , lookup
Methicillin-resistant Staphylococcus aureus wikipedia , lookup
BAD BUGS Healthcare Workers and Emerging Antibiotic Resistant Organisms JON ROSENBERG, M.D. DIVISION OF COMMUNICABLE DISEASE CONTROL CALIFORNIA DEPARTMENT OF PUBLIC HEALTH (510) 622-3427 [email protected] Bad Bugs Staphylococcus aureus Clostridium difficile Streptococcus pneumoniae Gram-negative bacilli (Pseudomonas, Acinetobacter, E. coli, Klebsiella) Enteric pathogens (Salmonella, Shigella, Campylobacter) 2 Bad Bugs and Healthcare Workers Staphylococcus aureus Clostridium difficile 3 Staphylococcus aureus Spherical gram-positive bacteria Long recognized as an important human pathogen and the leading cause of suppurative (pus forming) infections in humans The Romans referred to “good and laudable pus” 4 Staphylococcus aureus Exodus 9:9 And it shall become small dust in all the land of Egypt, and shall be a boil breaking forth with blains upon man, and upon beast, throughout all the land of Egypt Job 2:7 Job is smote with boils from the sole of his foot unto his crown 5 Staphylococcus aureus Discovered by Sir Alexander Ogston in 1881 and named for staphyle (bunch of grapes) and kokkus (grain or berry) because it appears microscopically in clusters resembling grapes Isolated and grown in pure culture by Anton Rosenbach in 1884; who called it aureus (golden) 6 Staphylococcus aureus in culture Staphylococcus aureus Part of normal human flora and ecological niche is typically the anterior nares ~ 20% of humans are persistently colonized (children > adults), 60% are intermittently colonized and another 20% are rarely colonized Most often spread via contaminated hands In 1928 Alexander Fleming first observed a mold called “penicillium” inhibit S. aureus in a culture plate The first treatment of a patient with penicillin took place in 1940 8 History of Methicillin-Resistant Staphylococcus aureus (MRSA S. Aureus is a borrower of genes, has few of its own Penicillin G introduced in 1941, penicillin-resistant (beta -lactamase producing) strains of S. aureus isolated 1942 To combat penicillin resistance, methicillin (first beta -lactamase stable penicillin) introduced in 1960 and methicillin-resistant strains of S. aureus first isolated in the United Kingdom in 1961 Late 1960s MRSA identified as nosocomial pathogen and first U.S. hospital outbreak reported in 1968 Resistance to other antimicrobials has occurred over time 9 Early Optimism about Antimicrobials William H. Stewart, U.S. Surgeon General 1965-1969 (and Minneapolis native), is purported to have said, “We have closed the book on infectious disease.” Hospital CAMRSA 101 Community associated, not acquired • Absence of healthcare associations • Not healthcare strains invading the community Healthcare associated (HAMRSA) • Presence of healthcare factors Different strains associated with each, may be blurred as CAMRSA strains cause HAMRSA infections (newborns, surgical site, transmitted in healthcare facilities) 12 CLINICAL MANIFESTATIONS CAMRSA Furuncle (boil), carbuncle, abscess Cellulitis Pyomyositis Necrotizing pneumonia Toxic shock syndrome Scalded skin syndrome 13 HAMRSA Surgical site infection Blood stream infection, particularly central linse associated Pneumonia, particularly ventilator associated S. aureus Skin Infections Furuncles (boils) 14 Cellulitis Mild Severe EPIDEMIOLOGY CAMRSA 15 Children and young adults, increased summertime, often no risk factors, irregular association with antibiotics Families, prisons, IVDU, sports teams, aboriginal populations HAMRSA Hospitalized patients (elderly), no seasonality, risk factors (antibiotics, medical devices, surgery, ventilators) Little transmission outside healthcare facilities VIRULENCE CAMRSA Rapid growth (2x in 28 minutes Slow growth (2x in 38 minutes Colonization:Infection ~4:1 Colonization:Infection ~10:1 10-fold increased risk of infection vs CAMSSA 16 HAMRSA GENOTYPE – RESISTANCE GENE CAMRSA SCCmec Type IV 17 HAMRSA SCCmec Type II and III, I Structures of SCCmec 18 Ito et al. Drug Resistance Updates 2003 GENOTYPE – DNA TYPE CAMRSA 19 HAMRSA PFGE: USA 300 and 400, USA 1000, USA 300 becoming predominant PFGE: USA 100, 200, 500, 600, 700, 800 MLST limited types within continent MLST multiple types within continent National Database of MRSA Pulsed-Field Types (Highlighted PFTs: historically community-associated) PFT MLST pvl USA300 8 IV POS USA700 72 IV NEG USA100 5 II NEG USA800 5 IV NEG USA400 1 IV POS USA500 8 IV, I I NEG USA1000 59 IV NEG/POS USA900 15 MSSA NEG USA600 USA200 45 36 II II NEG NEG USA1100 30 IV POS USA1200 McDougal et al J Clin Micro 2003;41:5113-5120 SCCmec MSSA POS GENOTYPE – PANTON-VALENTINE LEUKOCIDIN (PVL) GENE CAMRSA Present Highly associated with skin, soft-tissue infections, necrotizing pneumonia May contribute to pathogenesis or be marker 21 HAMRSA Absent Early CA-MRSA Reports Aboriginals in the Kimberley Range, Western Australia Reported in indigenous people around the world Causal Diagram for CA-MRSA Crowded Living Conditions/ Hygiene Person-to-Person Transmission Inappropriate/Increasing Use of Antimicrobials? Transfer of mecA gene from CNS to virulent S. aureus strains Selection of resistant strains (e.g. use of cephalexin [Keflex®] for SSTIs) CA-MRSA CA-MRSA Pyramid Invasive Infections Skin Infections Colonization CA-MRSA Pyramid ~14,0001 Invasive Infections / Yr Skin Infections Colonization 1. Klevens M et al JAMA 2007;298:1763-71 Most Invasive MRSA Infections are Healthcare-Associated National estimates: 94,360 infections; 18,650 deaths 31.8 cases & 6.3 deaths per 100,000 persons 28% 14% 59% Community-Associated (CA-MRSA) Healthcare-Associated, Community-Onset (HACO-MRSA) Healthcare-Associated, Hospital-Onset (HAHO-MRSA) Klevens et al JAMA 2007;298:1763-71 Severe CAMRSA Infections Necrotizing pneumonia and empyema • Francis JS. CID 2005;40(1):100-7 Sepsis syndrome • Gonzalez BE. Pediatrics 2005;115(3):642-8 Disseminated infections with septic emboli • Gonzalez BE. CID 2005;41(5):583-90 Musculoskeletal infections (pyomyositis, osteomyelitis) • Martinez-Aguilar G. PIDJ 2004;23(8):701-6 Necrotizing fasciitis • Miller LG. NEJM 2005;352(14):1445-53 Purpura fulminans • Adem PV. NEJM 2005;353(12):1245-51 Toxic shock-like syndrome • Durand G. J Clin Microbiol, 2006;44(3):847-53, Chi. Clin Infect Dis 2006;42:181-5 27 CA-MRSA Pyramid ~14,0001 Invasive Infections / Yr 11.6 million3 ambulatory visits for skin and soft tissue infections ~66,0002 Culture -confirmed CA-MRSA SSTI / Yr 80% of culture-confirmed CA-MRSA 55,0004 hospitalizations with MRSA skin and soft tissue infection Colonization 1. Klevens M et al JAMA 2007;298:1763-71 2.Fridkin SK et al. N Engl J Med. 2005;352 (14):1436-44. 3.McCaig LF et al. Emerg Infect Dis. 2006;12:1715-23 4. Elixhauser A and Steiner C. HCUP Statistical Brief #35 Hospitalizations for S. aureus Skin and Soft Tissue Infections Increasing Dramatically Klein E et al. Emerg Infect Dis 2007:13(12);1840-46. CA-MRSA Pyramid ~14,0001 Invasive Infections / Yr 11.6 million4 ambulatory visits for skin and soft tissue infections ~66,0002 Culture -confirmed CA-MRSA SSTI / Yr 55,0005 hospitalizations with MRSA skin and soft tissue infection Point Prevalence: 3-5 million5 persons with MRSA nasal colonization 1. Klevens M et al JAMA 2007;298:1763-71 2.Fridkin SK et al. N Engl J Med. 2005;352(14):1436-44. 4.McCaig LF et al. Emerg Infect Dis. 2006;12:1715-23 5. Elixhauser A and Steiner C. HCUP Statistical Brief #35 3. Gorwitz RJ et al. J of Infect Dis. 2008;197 Prevalence of MRSA Nasal Colonization has Increased but Remains Low National Health and Nutrition Examination Survey, 2001-04, N=18,626 USA300 / USA400: ↑d from 8% to 20% of all MRSA-colonized (NS) 1.5% 0.8% Gorwitz RJ et al. J of Infect Dis. Apr 15 2008: 197 Non-Nasal MRSA Colonization? Canada healthy newborn USA300 outbreak: • Sensitivity: Nares only 68%, Umbilicus only 61%, Rectum only 21%, Nares + Umbilicus 100% Manhattan household survey • 8/32 ♀ MRSA+ vagina or pubic (2/8 concurrent + nasal) LA inpatients & outpatients with CA-MRSA infection: • 40% colonized with MRSA in any of 4 sites • 26% nares, 8% axilla, 20% inguinal, 15% rectum Atlanta VA HIV Clinic (preliminary): • 70 (12%) of 578 MRSA-colonized in nose or groin – 33 (47%) both, 26 (37%) nose only, 11 (16%) groin only MRSA in Animals Food Animals • MRSA ST398 in pigs (Europe, Canada, U.S.), pig farmers (Europe, Canada), retail pork (Europe) • Health risks of MRSA in food products unknown Non-Food Animals • Transmission between humans and animals (both directions) described – small % of human infections • Strains reflect predominant human strains • Pets may play role in sustained household transmission • Little evidence to support antimicrobial decolonization in animals, but colonization typically short-lived Strategies for Clinical Management of MRSA in the Community http:www.cdc.gov/ncidod/dhqp/ar_mrsa_ca.html Skin Infections and MRSA Information for California Schools A Parent’s Guide to MRSA in California What You Need to Know http://www.cdph.ca.gov/HealthInfo/discond/Pages/MRSA.aspx MRSA Among U.S. ICU Patients, 1995-2004 Source: National Nosocomial Infections Surveillance (NNIS) System The APIC National MRSA Inpatient Survey: MRSA prevalence rates by state Am J Infect Control 2007;35:6 31-7.) Nosocomial CAMRSA Increasing prevalence of CAMRSA strains in healthcare-associated MRSA isolates Increasing ICU/NICU bloodstream infections NICU outbreaks – 9 reported to date Healthy newborns – 5 outbreaks reported to date Infections in postpartum women – 2 outbreaks CAMRSA prosthetic joint infections CAMRSA Infections in healthcare workers 38 Community-associated Methicillin resistant Staphylococcus aureus Isolates Causing Healthcare associated Infections Retrospectively examined all HA-MRSA isolates from patients in Harbor-UCLA Medical Center 1999–2004 – Emerg Infect Dis 2007;13(2) :236-42 CAMRSA NICU Outbreaks, Transmission San Diego: CA-MRSA necrotizing fasciitis in a neonate • Dehority W et al. Pediatr Infect Dis J 2006;25(11):1080-1081 Los Angeles: Transmission of CA-MRSA from breast milk • Gastelum DT et al. Pediatr Infect Dis J 2005;24(12): 1122-1124 Texas: CA-MRSA necrotizing pneumonia in a neonate • McAdams RM et al. J Perinatol 2005;25(10)677-679 Canada: CA-MRSA outbreak • Rosenthal A, et al. J Clin Micro 2006;44(11):4234-4236 Switzerland: CA-MRSA outbreak from mother with mastitis and wound infection • Sax H et al. J Hosp Infect 2006;63(1):93-100 Israel: CA-MRSA outbreak • Regev-Yochay. Emerg Infect Dis 2005;11:453-455 CA-MRSA outbreak linked to HCW • Stein M, et al. Pediatr Infect Dis J 2006;25(6):557-559 Saudi Arabia: Father to infant transmission of CA-MRSA • Al-Tawfiq JA. Infect Control Hosp Epidemiol 2006;27(6):636-637 UK: Nosocomial transmission of CA-MRSA 40 • David MD, et al. J Hosp Infect 2006;64(3):244-250 CAMRSA SSTIs Healthy Newborns Two clusters of MRSA skin infections among newborns, Los Angeles, 2004 – Infect Control Hosp Epidemiol 2007;28(4):406-411 Cluster of 11 MRSA skin infections, Chicago, 2004 – Arch Dis Child Fetal Neonatal ed 2007; Epub Cluster cases infants and mothers, NYC, 2002 – Emerg Infect Dis 2005;11(6):808-812 N. California hospital, April 2007 Predominant circumcised males, some colonized HCW, uncertain mode transmission 41 CAMRSA Infections in Postpartum Women New York: 8 postpartum women developed skin and soft tissue infections over 2 weeks • USA400, 178 HCWs negative nasal cultures – Clin Infec Dis 2003;37:1313-9 Chicago: 16 of 17 isolates from mothers with MRSA mastitis in 2005 – Emerg Infect Dis 2007;13(2):298-301 42 CAMRSA Infections in Healthcare Workers Two HCW developed MRSA skin and soft-tissue infections • Patient 1 cared for 15 patients with CAMRSA infections over several months and reported I&D many abscesses • Patient 2 administrative position w/out patient contact • 2 (3%)/70 HCW, 0/58 support staff colonized with MRSA • Seven (19%) of 36 environmental cultures grew MRSA – Patient examination table, computer keyboard, pulse oximeter, multiple patient chairs; no MSSA detected • All strains SCCmec-IV and matched by PFGE Infect Control Hosp Epidemiol 2006; 27:1133-1136 43 Role of Healthcare Workers in MRSA Transmission Carriage without colonization • Most common: transient carriage on hands due to inadequate hand hygiene, improper glove use • Skin and hand conditions (eczema, artificial /diseased nails) can increase risk Colonized HCW 44 • Documented in presence of medical conditions (eczema, respiratory infections) • Mode of transmission in absence of medical conditions uncertain Role of Healthcare Workers in MRSA Transmission In the absence of a clear role in transmission by asymptomatic healthy HCW, the role for screening asymptomatic healthy HCW, either routinely or in the presence of an outbreak is unclear Finding a strain in HCW that matches patient’s strains does not indicate the direction of transmission 45 How Often Do Asymptomatic Healthcare Workers Cause MethicillinResistant Staphylococcus aureus Outbreaks? A Systematic Evaluation 191 outbreaks identified in 1996-2005 database • 11 had strong epidemiological evidence for HCW transmission – In 3 asymptomatic carriers were the cause The frequent practice of screening asymptomatic HCWs should be reconsidered Vonberg et al. Infect Control Hosp Epidemiol 2006; 27:1123-1127 Outbreaks with Evidence of HCW Transmission 7 SSIs in a French Hospital 43 HCW screened, 1 colonized A member of the surgical team had chronic MRSA sinusitis. He admitted misuse of surgical face masks and bad handwashing procedures. 47 Outbreaks with Evidence of HCW Transmission 5 mediastinitis infections after open heart surgery in Taiwan hospital 33 HCW screened, 1 colonized Only 1 HCW, an assistant surgeon who had MRSA dermatitis of his right hand, attended all 5 operations 48 Outbreaks with Evidence of HCW Transmission 8 cases of postsurgical infections in U.S. hospital 64 HCW screened, 1 colonized Cases occurred only when nasally colonized physician had upper respiratory tract infections. Multivariate logistic regression analysis identified exposure to this physician as an independent risk factor for MRSA colonization. 49 Outbreaks with Evidence of HCW Transmission 32 cases of MRSA infection in U.S. hospital 14 HCW screened, 3 colonized Exposure to a respiratory therapist was an independent risk factor for infection, with an odds ratio of 10.5 in a case-control study. This HCW had a history of chronic sinusitis, and several successive cultures of nasals secretions yielded MRSA. After minor surgery to correct an anatomic defect of the paranasal sinuses, the nasal drainage ceased, and the therapist remained asymptomatic. No new cases of MRSA infection were observed 50 Outbreaks with Evidence of HCW Transmission 15 cases of obstetrical infections in British Hospital 146 HCW screened, 2 colonized • Healthy person with nasal carriage and student midwife with infected eczema of hand After mupirocin treatment was administered to both, consecutive nasal swabs were consistently negative for the strain Finally, the outbreak ended after the infected midwife was removed from duty 51 Outbreaks with Evidence of HCW Transmission 10 patients on a burn unit in U.S. hospital positive clinical cultures for MRSA When cases recurred after 2 months of enhanced infection control, all staff cultured 56 HCW screened, 3 colonized A surgical resident, a nurse, and a nursing assistant treated with mupirocin During 3 years of active surveillance thereafter, infection control personnel did not detect any additional patients who were colonized or infected with the epidemic MRSA strain 52 CAMRSA and Healthcare Workers Poorly studied Predominant strains (e.g. USA 300 precludes molecular epidemiology) HCW may be • Source or vectors of cross-infection • May become secondarily colonized or infected from patients • Colonization may be unrelated to colonization in patients 53 Healthcare-associated Outbreaks of CAMRSA Colonization and Infection Navarro et al. Current Opinion in Infectious Diseases 2008, 21:372–379 Decolonization of Healthcare Workers Can contribute to multifactorial approach for termination of nosocomial MRSA if applied early before MRSA becomes endemic in an institution Screening recommended for outbreaks in Europe and other countries with low endemicity Screening generally recommended in US only for HCW epidemiologic implicated in outbreak 55 Resources California Department of Public Health : http://www.cdph.ca.gov/HealthInfo/discond/Pages/MRSA.aspx Los Angeles County Department of Health Services: www.lapublichealth.org/acd/MRSA.htm Texas Department of State Health Services: www.tdh.state.tx.us/ideas/antibiotic_resistance/mrsa/professionals/ Washington State Department of Health: /www.doh.wa.gov/Topics/Antibiotics/providers_MRSA_guidelines.htm Minnesota Department of Health www.health.state.mn.us/divs/idepc/diseases/mrsa/camrsa/index.html CDC Community-Associated MRSA: 56 www.cdc.gov/ncidod/hip/aresist/mrsa_spotlight.htm Clostridium difficile Spore-forming, gram-positive anaerobic bacillus that produces two toxins: A and B First isolated in the mid-1930s; name comes from difficulty isolating (and meat) Soil, sand, hay, animal dung 15-25% of antibioticassociated diarrhea Increasing Prevalence and Severity of Clostridium difficile Colitis in Hospitalized Patients, US Prevalence of C difficile colitis presented as the hospital discharge rate for patients with either a principal or a secondary diagnosis of C difficile colitis Case fatality for patients with either a principal or a secondary diagnosis of C difficile colitis Ricciardi et al. Arch Surg. 2007;142:624-631 Yearly C difficile–related mortality rates per million population, United States, 1999–2004 Source: multiple cause-ofdeath data from national mortality records Redelings et al. Emerg Infect Dis 13:2007;1417-19 An Epidemic, Toxin Gene–Variant Strain of C difficile Major Genes in the Pathogenicity Locus (PaLoc) of C difficile and Relation to the Genes for Binary Toxin Genes tcdA and tcdB encode toxins A and B, respectively, whereas tcdD encodes a positive regulator of the production of toxins A and B. Gene tcdE encodes a protein that may be important for the release of toxin from the cell. Gene tcdC is a putative negative regulator of the production of toxins A and B. McDonald et al. N Engl J Med 2005;353:2433-41. States with the Epidemic Strain NAP1 of C.difficile Confirmed by CDC (N=27) Updated 4/3/2007 DC HI AK PR Clostridium difficile Infection among Health Care Workers Receiving Antibiotic Therapy In two surveys 45% of health care workers had received antibiotics within the past year These HCW should be at increased risk of C. difficile infection as the result of their workplace exposure HCW have 13-15% prevalence of C. difficile positive stool Few reports of infection 62 Demographic and clinical characteristics of 4 healthcare workers with Clostridium difficile infection. Arfons et al. CID 2005:40 Trends in nosocomial and community acquired CDAD at Children’s National Medical Center Benson et al. Infect Control Hosp Epidemiol 2007; 28:e Community Associated CDAD UK, 2005 Rates of Clostridium difficile per 100 000 Patients in the United Kingdom General Practice Research Database Dial S. et al. JAMA 2005;294:2989-2995 Severe Clostridium difficile--Associated Disease in Populations Previously at Low Risk Case 1. A woman aged 31 years 14 weeks pregnant with twins went to local emergency department after 3 weeks of intermittent diarrhea, followed by 3 days of cramping and watery, black stools 4--5 times daily Case 2. A girl aged 10 years went to a children's hospital ED because of intractable diarrhea, projectile vomiting, and abdominal pain. She had not taken antimicrobials during preceding year MMWR. December 2, 2005/54(47);1201-1205 Is Clostridium difficile-associated Infection a Potentially Zoonotic and Foodborne Disease? Clostridium difficile isolated from 12 (20%) of 60 retail ground meat samples purchased over 10-month period in 2005 in Canada 11 isolates toxigenic 8 (67%) classified as toxinotype III (one similar to 027) Rodriguez-Palacios. Emerg Infect Dis 13:207;485-7 There are also Good Bugs