The Challenges of Communicable Diseases Dr Christopher KC Lee Infectious Diseases Unit
Download ReportTranscript The Challenges of Communicable Diseases Dr Christopher KC Lee Infectious Diseases Unit
The Challenges of Communicable Diseases Dr Christopher KC Lee Infectious Diseases Unit Department of Medicine Sungai Buloh Hospital Malaysia Global Leading causes of Death 2002 WHO 2004 Dr Margaret Chan Director-General, WHO 3rd. April 2007 “The forces of globalization have changed the epidemiology of emerging and epidemic-prone diseases. From 1973 through 2003, when SARS appeared, 39 pathogenic agents capable of causing human disease were newly identified. You will recognize the names of some: Ebola, HIV/AIDS, and the organisms responsible for toxic shock syndrome and legionnaire’s disease. Others include new forms of epidemic cholera and meningitis, Hanta virus, Hendra virus, Nipah virus, H5N1 avian influenza and, of course, SARS. All of this within 30 years.” Emerging Pathogens Healthcare associated: Community: MRSA HIV MRSE Pandemic / Avian Flu VRE SARS VISA Foodborne diseases ESBL producing Gm-ve organisms Vector borne [malaria, dengue, West Nile] Multidrug resistant Hepatitis B & C Acinetobacter Legionnaire’s disease MDR-TB Pathogens of bioterrorism Center of Disease Control, USA Evolution of Drug Resistance in S. aureus Penicillin Methicillin MethicillinPenicillin-resistant S. aureus resistant [1950s] [1970s] S. aureus S. aureus (MRSA) [1997] Vancomycin [1990s] Vancomycin- resistant S. aureus [ 2002 ] Vancomycin intermediateresistant S. aureus (VISA) Vancomycin-resistant enterococci (VRE) Bacterial Resistance: An increasing threat to the successful treatment of nosocomial infections •VRSA •Carbapenem resistant Enterobacter/Klebsiella •MDR Pseudomonas/Acinetobacter • ESBL’s resistant to quionolones, aminoglycosides & piperacillin/tazobactam •Options for treatment are diminishing Antibiotic Resistance: The Global Perspective Enterococcus faecium oxazolidinone resistance USA 2001 Staphylococcus aureus vancomycin resistance (VRSA) USA 2002 Vibrio cholerae multiresistance Ecuador 1993 Enterococcus faecium vancomycin resistance France 1988 Neisseria meningitidis penicillin resistance Spain 1988 Klebsiella pneumoniae cefotaxime resistance Vancomycin intermediate Germany 1983 Staphylococcus aureus (VISA) Japan 1996 Salmonella typhi multiresistance India 1990 Shigella dysenteriae multiresistance Burundi 1992 Streptococcus pneumoniae multiresistance South Africa 1977 Neisseria gonorrhoeae penicillin resistance The Philippines 1976 Streptococcus pneumoniae penicillin resistance Australia 1967 Vancomycin-Resistant Enterococci 35 30 25 20 15 10 Non-ICU 5 2001 2000 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 0 1999 ICU Year Fridkin SK et al. Clin Chest Med. 1999;20:303-316. Re-emergence of Gram-negative Organisms in Nosocomial Bacteraemia (US data) % organisms among total isolates Coagulase-negative staphylococci Gram-negative organisms S. aureus Candida spp. 50 45 40 35 30 * 25 20 15 10 5 0 1996 1997 1998 1999 2000 2001 2002 2003 *p<0.001 (from 1999 to 2003) Albretch, et al. Arch Intern Med 2006;166:1289–1294 What is driving increasing prevalence of antibiotic resistant pathogens? •The selection of resistant mutants by antibiotic exposure •The transfer of genetic determinants of resistance between bacterial strains •The clonal spread of resistant bacteria among hospitalised patients within and between institutions and community (poor infection control) •Collateral damage BAD BUGS – FEW NEW DRUGS Introduction of New Antibiotic Classes Lipopeptides e.g Daptomycin Streptogramins Quinolones Chloramphenicol Tetracyclines Cephalosporins Macrolides Glycopeptides Monobactams, fosfomycin Aminoglycosides Carbapenems Penicillins Oxazolidinones e.g linezolid Sulphonamides 1930´s 1940´s 1950´s 1960´s 1970’s 1980´s 1990´s 2000´s Key Strategies Prevent infection Diagnose and treat infection effectively Clinicians hold the solution! Use antimicrobials wisely Prevent transmission CDC, USA Contain your contagion Isolate the pathogen Prevent Transmission Stop treatment when cured Know when to say “no” to vanco Treat infection, not colonization Use Antimicrobials Wisely 12 Steps in Addressing Treat infection, not contamination Access the experts Nosocomial Infections: Use local data Practice antimicrobial control Target the pathogen Get the catheters out Vaccinate Diagnose & Treat Effectively Prevent Infections Communicable Diseases Outbreaks: Lessons learnt & Preparing for … Major Social implications: HIV, SARS High Mortality: Nipah Encephalitis Endemic (recurrent): Dengue, Typhoid Endemic (new manifestations): Leptospirosis Global Implications: Avian Flu Pandemic Influenza: Are we prepared? Million Estimated number of people living with HIV globally, 1986–2006 50 40 Number of people living with HIV 30 20 10 0 1986 1988 1990 1992 1994 1996 Year 1998 2000 2002 2004 2006 HIV prevalence in adults in Asia, 1990−2005 Adults & children estimated to be living with HIV, 2006 Eastern Europe Western & Central Europe & Central Asia North America 740 000 1.4 million [580 000 – 970 000] [880 000 – 2.2 million] Caribbean 250 000 Latin America 1.7 million [1.2 – 2.6 million] Middle East & North Africa [190 000 – 320 000] [1.3 – 2.5 million] 1.7 million 460 000 [270 000 – 760 000] Sub-Saharan Africa 24.7 million [21.8 – 27.7 million] East Asia 750 000 [460 000 – 1.2 million] South & South-East Asia 7.8 million [5.2 – 12.0 million] Oceania 81 000 [50 000 – 170 000] Total: 39.5 (34.1 – 47.1) million Estimated number of adults and children newly infected with HIV, 2006 Western & Eastern Europe Central Europe & Central Asia 22 000 North America 43 000 [34 000 – 65 000] Caribbean 27 000 [18 000 – 33 000] 270 000 [170 000– 820 000] East Asia Middle East & North Africa [20 000 – 41 000] 68 000 [41 000 – 220 000] Sub-Saharan Africa Latin America 140 000 [100 000 – 410 000] 2.8 million [2.4 – 3.2 million] 100 000 [56 000 – 300 000] South & South-East Asia 860 000 [550 000 – 2.3 million] Oceania 7100 [3400 – 54 000] Total: 4.3 (3.6 – 6.6) million Estimated adult and child deaths from AIDS, 2006 Western & Eastern Europe Central Europe & Central Asia 12 000 North America 18 000 [11 000 – 26 000] Caribbean 19 000 [<15 000] 84 000 [58 000 – 120 000] East Asia Middle East & North Africa [14 000 – 25 000] 36 000 [20 000 – 60 000] Latin America Sub-Saharan Africa [51 000 – 84 000] [1.8 – 2.4 million] 65 000 2.1 million 43 000 [26 000 – 64 000] South & South-East Asia 590 000 [390 000 – 850 000] Oceania 4000 [2300 – 6600] Total: 2.9 (2.5 – 3.5) million Over 11 000 new HIV infections a day in 2006 • More than 95% are in low and middle income countries • About 1500 are in children under 15 years of age • About 10 000 are in adults aged 15 years and older of whom: — almost 50% are among women — about 40% are among young people (15-24) Cummulative HIV infections Malaysia 1993-2006 80000 70000 60000 50000 40000 30000 20000 10000 73427 70559 64439 58012 51256 44278 38340 33233 28541 23917 19993 15396 11198 7805 0 Malaysia 30/6//06 Year 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Jun-06 National Strategic Plan 2006 Endorsed by the Cabinet in April 2006 Main Objectives in NSP Strengthening Leadership & Advocacy Training & Building Human Capital Reducing Vulnerability of Drug users Reducing Vulnerability of Women & Children Reducing Vulnerability of other High Risk groups eg. CSW, MSM. Increasing Access to Treatment, Care & Support In support of the UNGASS (AIDS) declaration Strengthening Leadership & Advocacy 3 tiered policy making structure within government Cabinet Committee on AIDS chaired by the Deputy Prime Minister National Advisory Committee on AIDS chaired by the Minister of Health Technical Committee on AIDS chaired by the DG of Health Broad platform of engagement Multisectoral esp. non-health sector Nipah Encephalitis Malaysian origin Nipah virus; Zoonotic infection: first isolated in 1999, named after location it was first detected in Malaysia. Caused disease in animals, & in humans through contact with infected animals. Outbreak of encephalitis in Malaysia, (initially in Ipoh then Bukit Pelanduk) from Sept 98-April 99. A total of 265 people infected, of whom 105 died, & 93% of cases had a history of occupational exposure to pigs. An associated outbreak among abattoir workers in S’pore in March 99: 11 cases, with 1 death. These workers had been handling pigs imported from outbreak areas in Malaysia. Nipah: a public health concern Although both Nipah and Hendra, a closely related zoonotic virus isolated in Australia (1994), have caused only a few focal outbreaks, their biologic property to infect a wide range of hosts and to produce a disease causing significant mortality in humans has made this emerging viral infection a public heath concern. Both Nipah & Hendra: members of the virus family Paramyxoviridae. Nipah virus Natural Host Certain species of fruit bats are natural hosts of both Nipah & Hendra viruses. Distributed across an area encompassing northern, eastern & south-eastern areas of Australia, Indonesia, Malaysia, the Philippines & some Pacific Islands. Bats appear to be susceptible to infection with these viruses, but do not themselves become ill. It is not exactly known how the virus is transmitted from bats to animals. Transmission: Nipah virus Mode of transmission from animal - animal, & from animal to human is uncertain. Appears to require close contact with tissue or body fluids from infected animals. Nipah Ab have been detected in pigs, other domestic & wild animals. Role of other species in transmitting infection to other animals not yet determined. Nipah not easily transmitted to man. Despite frequent contact between fruit bats & humans; no serological evidence of human infection among bat carers. Pigs: apparent source of infection among human cases in M’sia. Human-to-human transmission of Nipah virus has not been reported. Clinical features: Nipah encephalitis Incubation period: between 4 - 18 days. Many cases mild or inapparent (sub-clinical). In symptomatic cases, onset usually with "influenza-like" symptoms, with high fever & muscle pains (myalgia). Disease may progress to encephalitis; with drowsiness, disorientation, convulsions & coma. 50%percent of clinically apparent cases die. Learning Points: Early & accurate surveillance crucial Early identification of pathogen would have resulted in earlier control of outbreak ‘giving a name for my pain” Multisectoral cooperation important in dealing with large outbreaks ‘ ’working together’ Risk communication esp.with regards to media. ‘control the panic’ Preparedness of hospitals to deal with patient burden: ‘’no learning curve’ Severe Acute Respiratory Syndrome (SARS) WHO Disease Outbreak (11/7/2003) SARS first recognised on 26/2/03 in Hanoi, Vietnam Causative agent identified as novel type of coronavirus. Main symptoms /signs include high fever (>38 °C), cough, SOB or breathing difficulties. A proportion of patients with SARS develop severe pneumonia; some of whom needed ventilator support. As of 11/7/2003, total of 8437 cases with 813 deaths reported from 30 countries. SARS in Singapore Rapid spread: 200 cases in 6 weeks SARS in Hong Kong Deaths: 299 Probables: 1755 (22/7/2003) Nature Health care workers of Hospitals/Clinics and medical students Total Admission (Up till 22/7/2003) 386 Patients, family members & visitors 1369 Total admission 1755 Infection Control ….. our lifesaver Learning Points: Malaysia’s report card: 5 cases No local transmission External infective source ‘learning from others’ Triage at nation’s entry points Designated hospitals ‘controlling interface’ Protection of HCWs: most vulnerable possible reservoir surveillance Isolation facilities: grossly inadequate improvisation Effective media relations ‘structured access’ Leptospires Tightly coiled spirochetes Requires special media to grow Very slow grower Epidemiology Source of infection – From direct or indirect contact of urine of an infected animal – Maintenance hosts (reservoirs) Infection is endemic Transferred from animal to animal by direct contact Chronic infection of the renal tubules of infected animals with intermittent renal excretion Different species can be reservoirs for different serovars – Accidental / Incidental hosts Risk factors for Infection – Occupational Direct contact – livestock farmers, veterinarians Indirect contact – sewer workers, soldiers, miners, rice field workers – Recreational Water sports – Activities of daily care Walking bare foot in damp conditions Gardening with bare hands Dogs, rats Leptospirosis: clinical pyramid Icteric Leptospirosis Febrile illness of sudden onset Chills, headache, myalgia, abdominal pain, conjunctival suffusion Sub clinical or of very mild severity. No medical attention sought Old Foe – new presentation 19 yr old Malay male admitted on 17/5/05 in Melaka GH, with 1 week - fever & sore throat. Cough initially with whitish sputum, became blood stained 3 days before admission. Had dyspnoea pleuritic chest pain 1 day prior to admission. H/O going to Air Terjun Lata Kijang in Perak a week before onset. On admission, Temp 39oC, No jaundice. Required ventilation on the same day of admission for severe pulm hemorrhage. CXR: diffuse alveolar shadows relatively sparing apices. Hb 10g/dl, TWC 8.5x109/L, Platelet 128x109/l, Creat 113mmol/l, ALT 32U/L, APTT ratio 0.99, INR 1.03. Treated initially as severe CAP - Clarithromycin & Ceftriaxone. Dengue IgM, SARS antibody test, Mycoplasma & HIV serology -ve. However his Leptospiral serology was positive, 1:840. Commenced C. pencillin. Improved & was extubated on 2.06.05 Pulmonary hemorrhage Several reports of leptospirosis presenting as pulmonary hemorrhage from Taiwan, UK, USA, India, Brazil and tropical areas of Australia In Peru, 7 patients with histories of only urban exposure to leptospirosis had severe pulmonary manifestations – Clin Infect Dis, 2005. 40(3): p. 343-51. In Seychelles (Indian Ocean), 19% of the patients had pulmonary hemorrhage – Am J Trop Med Hyg, 1998. 59(6): p. 933-40. Avian Influenza: Toll 2003-07 Countries Cases [confirmed] Deaths Vietnam 95 42 Indonesia 102 81 Thailand 25 17 Iraq 3 2 Turkey 12 4 Azerbaijan 8 5 Cambodia 7 7 Egypt 38 15 China 25 16 Cumulative cases: • 319 cases • 192 deaths Mortality: 60% 25th. July 2007 Objectives of strategic actions Preparation: Guidelines (MOH – NIPPP) Use of antiviral drugs during pandemic Recommendation of priority population groups for vaccination during Influenza Pandemic Guidelines for Entry Point Screening of travelers from / exiting Influenza affected countries or areas Health Declaration Card for travelers exiting Influenza affected countries or areas. Guidelines on isolation, home surveillance & quarantine of contacts during flu pandemic. Guidelines for self-monitoring & reporting if ill of influenza during pandemic. Plus many others ….. Facilities & Equipment Minimum standards laid down in NIPPP must be complied to. When resources allow; the best standards achievable should be goal eg. Isolation facilities Any lack of critical facilities & equipment should be addressed and corrected in descending priority Safety of patients and staff should be paramount in all medical decision making (evidence based) Medications Antivirals & pandemic influenza vaccine will be centrally controlled & distributed Stock pile of antivirals to be kept at regional centers allowing for rapid deployment when needed Due to limited supply, usage must comply with indications listed in NIPPP Usage of antivirals must be closely monitored Testing Our Systems Simulation Exercise: - tabletop - ‘real-life’ / actual Check our surge capacity … - testing our limit Prepare for worse case scenarios Keep preparation plans realistic and keep scenarios plausible ‘Think out of the box’ Dr Margaret Chan Director-General, WHO World Health Day 2nd. April 2007 “The best defence against emerging and epidemic-prone diseases is not passive barriers at borders, airports and seaports. It is proactive risk management that seeks to detect an outbreak early and stop it at source – before it has a chance to become an international threat. We are now in a good position to act in this pre-emptive way.”