1 / 32

THE ROLE OF THE ENVIRONMENT IN THE TRANSMISSION OF BACTERIA AND VIRUSES AMONGST CHILDREN

DESIGNING A SAFER TOMORROW POUR UN FUTUR PLUS SAIN. THE ROLE OF THE ENVIRONMENT IN THE TRANSMISSION OF BACTERIA AND VIRUSES AMONGST CHILDREN. SYED A. SATTAR, Ph.D . DIRECTOR, CENTRE FOR RESEARCH ON ENVIRONMENTAL MICROBIOLOGY (CREM) UNIVERSITY OF OTTAWA, OTTAWA, ON, CANADA. INTRODUCTION.

Jimmy
Download Presentation

THE ROLE OF THE ENVIRONMENT IN THE TRANSMISSION OF BACTERIA AND VIRUSES AMONGST CHILDREN

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DESIGNING A SAFER TOMORROW POUR UN FUTUR PLUS SAIN THE ROLE OF THE ENVIRONMENT IN THE TRANSMISSION OF BACTERIA AND VIRUSES AMONGST CHILDREN SYED A. SATTAR, Ph.D. DIRECTOR, CENTRE FOR RESEARCH ON ENVIRONMENTAL MICROBIOLOGY (CREM) UNIVERSITY OF OTTAWA, OTTAWA, ON, CANADA

  2. INTRODUCTION • WHY THE EMPHASIS ON CHILDREN? • WHY THE CONCERN WITH BACTERIAL & VIRAL INFECTIONS? • NEWER PATHOGENS & NEWER ROLES FOR THEM? • LONGER-TERM IMPACTS OF INFECTIONS? • WHAT IS THE GLOBAL PICTURE? • WHAT IS THE SITUATION IN CANADA & THE U.S.? • HOW DO BACTERIA & VIRUSES SPREAD IN NATURE? • WHAT ROLE DOES THE ENVIRONMENT PLAY? • HOW CAN ENVIRONMENTAL SPREAD BE INTERRUPTED? • WHAT DOES THE FUTURE HOLD? SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  3. TERMS OF REFERENCE • A CHILD: ANY PERSON UNDER 18 YEARS OF AGE • THE ENVIRONMENT: ANYTHING OUTSIDE THE BODY OF THE HUMAN HOST SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  4. WHY THE EMPHASIS ON CHILDREN? • MORE VULNERABLE TO INFECTION • GREATER EXPOSURE TO MICROBES • POTENTIAL FOR LONGER-TERM HEALTH IMPACT • DEPENDENCE ON CARE-GIVERS • LOWER LEVELS OF AWARENESS • INCREASING GROUPING IN DAYCARE CENTERS • POVERTY, MALNUTRITION & NEGLECT SIMPLY PUT, A HEALTHY CHILD IS MORE LIKELY TO BE A HEALTHY ADULT SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  5. WHY WORRY ABOUT THE GLOBAL PICTURE? “NO ONE IS SAFE UNTIL EVERYONE IS SAFE” • INFECTIONS CONTINUE TO BE A MAJOR KILLER OF CHILDREN WORLDWIDE (GRAPHS) • INCREASING LEVELS OF • POLLUTION • POVERTY • MALNUTRITION • IMPACT OF NATURAL DISASTERS • IMPACT OF DISEASES SUCH AS AIDS • OVC’S (ORPHANS & VULNERABLE CHILDREN) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  6. CHILDREN AND BASIC DEPRIVATION FACTORS(UNICEF, STATE OF THE WORLD CHILDREN, 2005) AIDS HAS CREATED 15 MILLION OVC’S SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  7. DEMOGRAPHICS IN CANADA AND THE U.S. – 2003*(http://www.unicef.org/statistics/index_countrystats.html) *BASED ON UNICEF REPORT THE STATE OF WORLD’S CHILDREN, 2005 SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  8. MAIN CAUSES OF DEATH AMONG CHILDREN 0-4 YEARS(WORLD HEALTH ORGANIZATION, 1999) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  9. CAUSES OF PREMATURE DEATH AMONGST 0-44 YEAR OLDS (WORLD HEALTH ORGANIZATION, 1999) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  10. BREAKDOWN OF KNOWN HUMAN PATHOGENS(TAYLOR ET AL. PHIL. TRANS. R. SOC. LOND. B. 2001; 356:983-989) 538 BACTERIA OF THESE 1415 PATHOGENS, THE MEANS OF SPREAD OF >200 ARE NOT KNOWN!! (38%) 217 VIRUSES & PRIONS (15%) 287 HELMINTHS (20%) BACTERIA & VIRUSES TOGETHER CONSTITUTE >50% OF KNOWN HUMAN PATHOGENS 307 FUNGI (22%) 66 PROTOZOA (5%) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  11. HUMAN HEALTH IMPACT OF INFECTIOUS AGENTS • GLOBALLY, INFECTIONS DIRECT CAUSE OF >32% (18/56 MILLION) OF ALL DEATHS/YEAR; >45% IN DEVELOPING COUNTRIES(WHO 2001) • 40 NEW PATHOGENS FOUND IN PAST 30 YEARS ALONE (DESSELBERGER, J. INFECT. 2000; 40:3-15) • INFECTIONS & DELAYED OUTCOMES, E.G., POST-POLIO & GUILLAIN-BARRÉ SYNDROMES (WHO 2003) • VIRUSES (HBV, HCV, HPV) & BACTERIA (H. PYLORI) CAUSING CANCERS (WHO 2003) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  12. HEALTH IMPACT (CONT’D.) • CHRONIC CONDITIONS (ARTERIOSCLEROSIS, ARTHRITIS) • EXACERBATION OF ASTHMA • POLYMICROBIC DISEASES E.G., ~15% OF CASES OF ACUTE OTITIS MEDIA DUE TO A MIXTURE OF VIRUSES & BACTERIA (HEIKKINEN & CHONMAITREE. CLIN. MICROBIOL. REV. 2003; 16:230-241.) • VIRUSES & OBESITY – INFECTOBESITY (DHURANDHAR, J. NUTR. 2001; 131:2794S-2797S) • INFECTIONS & BEHAVIORAL CHANGES, E.G., TOXOPLASMA GONDII (BERDOY ET AL. PROC R SOC LOND. B BIOL. SCI. 2000; 267:1591-1594) • LACK OF NEW VACCINES & DRUGS • DECREASING RATES OF CHILDHOOD VACCINATIONS SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  13. GLOBAL HEALTH IMPACT OF ROTAVIRAL INFECTIONS - 1986-2000(PARASHAR ET AL. EMERG. INFECT. DIS. 2003; 9: 565-572) • SAFE & EFFECTIVE VACCINE STILL UNAVAILABLE • PERSONAL & ENVIRONMENTAL HYGIENE EFFECTIVE IN PREVENTING SPREAD OF ROTAVIRAL INFECTIONS • RELATIVE IMPORTANCE OF VARIOUS VEHICLES REMAINS UNCLEAR SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  14. MODES & MEANS OF PATHOGEN SPREAD IN NATURE Susceptible host H O R I Z O N T A L Infected host HORIZONTAL SPREAD V ERT I CAL Infected host Susceptible host Direct (person-to-person) Infected host Susceptible host Indirect Indirect spread is through vehicles such as water, food, air, fomites, insects, animals, soil, hands, environmental surfaces, medical devices & transplanted blood & tissues Susceptible host SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  15. ENVIRONMENTAL SPREAD OF INFECTIOUS AGENTS SOIL (CLOSTRIDIUM TETANI) MEDICAL DEVICES (HEPATITIS B VIRUS) ENVIRON. SURFACES (HEPATITIS A VIRUS) WATER (CRYPTOSPORIDIUM) FOOD (CAMPYLOBACTER) HUMAN HOST AIR (INFLUENZAVIRUS) INSECTS (WEST NILE VIRUS) HANDS (ROTAVIRUS) ANIMALS (HANTAVIRUS) WASTES (ESCHERICHIA COLI O157:H7) SECONDARY HOSTS (TOXOPLASMA GONDII) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  16. SPREAD OF INFECTIONS IN NATURE PATHOGEN SOURCE INSECTS ENVIRON. SURFACES WATER FOOD HANDS AIR ANIMALS SUSCEPTIBLE HOST SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  17. BACTERIA, PARASITES & VIRUSES IN FOODBORNE DISEASE IN THE U.S.(FROM MEAD ET AL., 1999) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  18. FELINE CALICIVIRUS SURVIVAL ON FOODS AT 4°C BIDAWID ET AL. UNPUBLISHED DATA SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  19. FELINE CALICIVIRUS SURVIVAL ON METAL DISKS AT 4°C BIDAWID ET AL. UNPUBLISHED DATA SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  20. SURVIVAL OF SELECTED ORGANISMS ON HANDS OF ADULTS AFTER ONE HOUR NEARLY 45% OF FCV REMAINS DETECTABLE ON THE HANDS OF ADULTS AFTER 20 MINUTES OF DRYING SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  21. GENERAL MEANS TO INTERRUPT SPREAD OF PATHOGENS • VACCINATION (POLIO) • PASSIVE IMMUNIZATION (HEP. A) • CHEMOTHERAPY (ANTIBIOTICS) • VACCINATION OF ANIMALS (RABIES) • DISEASE SURVEILLANCE (TB) • QUARANTINE (RABIES) • BARRIER PROTECTION (AIDS) • SCREENING OF BLOOD & TISSUES (HEP. B) • QUALITY CONTROL ON IMPORTS (CYCLOSPORA) • EDUCATION (TOXOPLASMOSIS) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  22. ENVIRONMENTAL CONTROL MEASURES • WATER TREATMENT & DISTRIBUTION • FOOD TREATMENT & PRESERVATION • AIR FILTRATION & DISINFECTION • LIQUID & SOLID WASTE COLLECTION, TREATMENT & DISPOSAL • CONTROL OF ANIMALS & INSECTS • CONTROL OF SECONDARY HOSTS • STERILIZATION • HANDWASHING • CLEANING/DISINFECTION SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  23. ALCOHOL-BASED HAND RUBS AND FELINE CALICIVIRUS(SATTAR ET AL., UNPUBLISHED DATA) THE FINGERPAD METHOD (ASTM 1838) WAS USED. TEN µL OF VIRUS IN SOIL LOAD WAS PLACED ON EACH FINGERPAD & DRIED. THE DRIED INOCULUM WAS EXPOSED TO CONTROL OR TEST SOLUTION FOR 30 SECONDS. THE FINGERPADS WERE ELUTED & ELUATES PLAQUE ASSAYED. SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  24. AN ALCOHOL-BASED GEL AND CORONAVIRUS 229E(SATTAR ET AL., UNPUBLISHED DATA) THE FINGERPAD METHOD (ASTM 1838) WAS USED. TEN µL OF VIRUS IN SOIL LOAD WAS PLACED ON EACH FINGERPAD & DRIED. THE DRIED INOCULUM WAS EXPOSED TO CONTROL OR TEST SOLUTION FOR 30 SECONDS. THE FINGERPADS WERE ELUTED & ELUATES PLAQUE ASSAYED. SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  25. CHEMICAL DISINFECTION TO INTERRUPT ROTAVIRUS SPREAD* TREATMENT NO. INFECTED % OF VIRUS NO. TESTED INFECTED NONE 13/14 93 LYSOL DISINFECTANT SPRAY 0/14 0 Virus in fecal suspension was dried on plastic plates and volunteers asked to lick the surface with and without disinfection. Ward et al., J. Clin. Microbiol. 29: 1991-1996, 1991. SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  26. EMERGING ISSUES • INCREASED SCRUTINY OF MICROBICIDES WITH MICROBICIDAL ACTIVITY AS ONLY ONE COMPONENT IN ACCEPTANCE & USE • FLAWED TEST METHODOLOGY • PROSPECTS FOR REGIONAL/GLOBAL HARMONIZATION • IMPROVED AWARENESS IN END-USERS • TREATED ARTICLES • MICROBICIDES & ANTIBIOTIC RESISTANCE (?) • MICROBICIDE RESIDUES & ENHANCED BACTERIAL SPORULATION (WILCOX & FAWLEY. LANCET 2000; 356; 1324.) SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  27. HAZARDS IN MICROBICIDE USE • SOME 300 CHEMICALS USED AS MICROBICIDES; MANY ARE NOW UNDER SCRUTINY • MICROBICIDES ARE A DOUBLE-EDGED SWORD • NO CHEMICAL THAT CAN KILL PATHOGENS CAN BE TOTALLY SAFE FOR OTHER LIFE FORMS • DAMAGE TO THE ENVIRONMENT • VOLATILE ORGANICS & AIR QUALITY • DISRUPTION OF HORMONE FUNCTIONS • CHANGES IN BIOFILM COMPOSITION • COMBINED IMPACT OF CHEMICALS & PATHOGENS SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  28. HOUSEHOLD MICROBICIDES & CHILDREN(M. SPANN ET AL., AM. J. PUB. HLTH. 2000;90:971-973) • ANNUALLY ABOUT 800,000 CHILDREN (<6 YEARS IN AGE) IN THE U.S. INGEST HOUSEHOLD PESTICIDES • MEDICAL ATTENTION NEEDED IN 10% OF THE CASES • MICROBICIDES INVOLVED IN >90% OF SEVERE CASES WORKING YOUTH & DISINFECTANTS(BREVARD ET AL., ENVIRON HLTH PERSPECT. 2003;111:1654-1659) • ACUTE OCCUPATIONAL EXPOSURE TO DISINFECTANTS IN WORKING YOUTH (15-17 YEARS OF AGE) IN THE U.S. • ANALYSIS OF 300 CASES IN A 5-YEAR PERIOD (1993-1998) • THE RATE OF EXPOSURES 4-FOLD HIGHER IN THE YOUTH AS COMPARED TO THAT IN 24-44 YEAR OLDS. • 45% OF CASES OF ILLNESS INVOLVED SOD. HYPOCHLORITE NEED BETTER EDUCATION OF PARENTS SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  29. REASONS FOR DESPAIR • UNABATED POPULATION INCREASE • LEVELS OF POVERTY RISING • AIR & WATER POLLUTION STILL TOO HIGH • CLIMATE CHANGE WILL IMPACT DISEASE SPREAD • INCREASING ANTIBIOTIC RESISTANCE • AIDS CONTINUES ITS ONSLAUGHT • VACCINATION RATES IN CHILDREN DROPPING • RECENT (OCT. 2005) CASES OF POLIO IN THE U.S. • REDUCED EMPHASIS ON PREVENTIVE STRATEGIES SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  30. REASONS FOR HOPE • RENEWED EMPHASIS ON BETTER NUTRITION • ELIMINATION/ERADICATION OF MANY CHILDHOOD DISEASES • OVER 90% OF CHILDREN IN CANADA AND THE U.S. IMMUNIZED AGAINST COMMON CHILDHOOD DISEASES • UN TREATY ON RIGHTS OF CHILDREN • AN INTERNATIONAL TREATY THAT RECOGNIZES THE HUMAN RIGHTS OF CHILDREN • AS OF NOV. 2003, TREATY RATIFIED BY 192 COUNTRIES, MORE THAN ANY HUMAN RIGHTS TREATY IN HISTORY • SOMALIA UNABLE TO RATIFY AS IT HAS NO RECOGNIZED GOVERNMENT • IN THE U.S., THE REVIEW TO RATIFY MAY TAKE SEVERAL YEARS SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  31. CONCLUDING REMARKS • PROTECTION OF CHILDREN FROM INFECTIONS IN GENERAL REQUIRES SPECIAL CONSIDERATION EVEN IN DEVELOPED COUNTRIES • WIDE VARIATIONS & GAPS IN STANDARDS OF HYGIENE EDUCATION & PARENTAL AWARENESS • SAFE & EFFECTIVE ENVIRONMENTAL CONTROL MEASURES LACKING • USE OF MICROBICIDES IN HAND ANTISEPSIS & DISINFECTION OF ENVIRONMENTAL SURFACES REQUIRES REVIEW. • REVIVAL OF EMPHASIS ON PREVENTION NEEDED SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

  32. ACKNOWLEDGMENTS • DR. LIZ SCOTT & OTHERS AT THE CENTER FOR HYGIENE & HEALTH IN HOME & COMMUNITY, SIMMONS COLLEGE SYED A. SATTAR, SIMMONS COLLEGE SYMPOSIUM, OCT., 2005

More Related