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<ul><li><p>NATURAL DISASTERS-</p><p>A MICROBES PARADISE</p><p>- Andrea J. Linscott</p><p>(Clinical Microbiology News Letter 29(8) April 2007)</p></li><li><p>Natural Disaster</p><p>DroughtEarthquakes</p><p>Hurricanes</p><p>TsunamiTornados</p><p>Flooding</p><p>Transmission of infectious agents</p></li><li><p>Impact phase (0-4 days)</p><p>Extrication, Immediate soft tissue infection</p><p>Post impact phase (4 d 4 w)</p><p>Air- borne Disease Food -borne disease</p><p>Water -borne disease Vector- borne disease</p><p>Recovery phase (After 4 weeks)Those with long incubation(Leptospirosis , Leishmaniasis)</p></li><li><p>Most common causes of death in a disaster</p><p> Diarrhea</p><p> Acute respiratory infection</p><p> Measles</p><p> Malaria</p><p> Malnutrition</p><p>- WHO</p></li><li><p>Factors that facilitate the spread of Microorganisms during a natural disaster</p><p> Disruption of public water &amp; sewage system</p><p> Crowded living conditions</p><p> Air borne transmission</p><p>Lack of immunization</p><p> Injury related infection due to exposure to some debris</p></li><li><p>Communicable diseases with epidemic potential in natural disasters</p><p>Waterborne Transmission Incubation period</p><p>Cholera Fecal/oral, 2h-5d</p><p>Lepto-spirosis contaminated water 2-28d</p><p>Hepatitis or food 15-50d</p><p>Bacillary dysentery 12-96h</p><p>Typhoid fever 3-14d</p></li><li><p>Acute respiratory</p><p>Pneumonia Person to person by 1-3d</p><p>airborne respiratory</p><p>droplets</p><p>Direct contact</p><p>Measles Person to person by 10-12d</p><p>airborne respiratory</p><p>droplets</p><p>Bacterial </p><p>Meningitis 2-10d</p></li><li><p>Vector-borne</p><p>Malaria Mosquito 7-30d</p><p>Dengue fever Mosquito 4-7d</p><p>Japanese encephalitis Mosquito 5-15d</p><p>Yellow fever Mosquito 3-6d</p></li><li><p>Diagnosis</p><p> Direct microscopic observation of V cholerae in stool</p><p> Leptospira-specific IgM serologic assay</p><p> Serologic assay detecting anti-HAV of anti-HEV IgM antibodies</p><p> Suspect if bloody diarrhea; confirmation requires isolation of organism from stool</p><p> Culture from blood, bone marrow,bowel fluids; rapid antibody tests- Salmonella typhi</p><p>Clinical presentation; culture respiratory secretions-Streptococcuspneumoniae, Haemophilus influenzae,</p><p>Generally made by clinical observation-Measles </p><p>Examination of CSF - Meningitis</p></li><li><p>Vector-borne</p><p> Parasites on blood smear,rapid diagnostic methods</p><p> Serum antibody testing with ELISA or rapid dot-blot technique-Dengue</p><p> Serologic assay for JE virus IgM specific antibodies in CSF or blood</p><p> Serological assay for yellow fever virus antibodies</p></li><li><p>Northridge Earthquake 1994.</p><p>An unusual outbreak of coccidiomycosis </p><p>occurred</p><p>The infectious fungal spores of Coccidioides immitiswere dispersed via large dust clouds generated by landslides triggered by the earthquake.</p><p>C.immitis peaked 2 weeks after the earthquake</p></li><li><p>Flooding</p><p>Accounts for 40% of all natural disasters </p><p>Communicable disease transmitted during the flooding</p><p>Water borne diseases Vector borne diseases</p><p> Typhoid fever Malaria</p><p> Cholera Yellow fever</p><p> Leptospirosis Water Nile fever</p><p> Hepatitis A Dengue</p></li><li><p> Diarrheal diseases after flooding and related displacement.</p><p> Outbreak of diarrheal diseases after flooding in Bangladesh in 2004 involved &gt; 17,000 cases of V.Cholerae and E.Coli infections.</p><p> In a large study in Indonesia in 1992-1993 S. enterica</p><p>paratyphi (paratyphoid fever) predominant</p><p> Risk of diarrheal diseases outbreaks following natural disaster</p><p>is higher in developing countries than in industrialised countries.</p></li><li><p> Dominican republic-Hurricanes David </p><p>and Fredrick, August 31 and Sep 5 ,1979</p><p>Marked increase in Typhoid,gastroenteritis,Measles,viral-hepatitis-measured 6 months after the Hurricane</p><p> Over 75,000 cases of Plasmodium falciparum malaria associated with hurricane Flora (haiti) 1966</p><p> Following hurricane Katrina (2005) several types of infections were seen</p><p> V.Cholerae were confirmed among Katrina evacuees.</p><p> No disease causing E.coli (CDC report)</p></li><li><p>Tsunamis</p><p> Infections associated with tidal wave include traumatic wound infections</p><p> Aspiration pneumonia due to inhalation of soil contaminated salt water</p><p>Wound infections among survivors were polymicrobic-641 organisms were identified</p><p> Most prominent-Aeromonas species, E.coli ,Klebsiella pneumoniae &amp; Psudomonas aeruginosa</p><p> Some of these organisms were resistant to all licensed antibiotics</p></li><li><p> Bacteriological Analysis of water samples from Tsunami hit coastal areas of Kanyakumari District, TamilNadu</p><p> 151 drinking water sources collected from tsunami-affected villages and relief shelters</p><p> 37 % of the water samples were contaminated.</p><p>No reports of acute diarrheal diseases or typhoid during the post-tsunami period </p><p>A report by the Department of Microbiology,University of Madras</p><p>P.Rajenndran et al,Indian Journal of Medical Microbiology(2006) 24 (2):114</p></li><li><p> Relationship between natural disasters and communicable diseases frequently misconstrued</p><p> Fear derived from an association between large no of dead bodies and epidemics</p></li><li><p>Primary risk factors</p><p> Population displacement. </p><p> Availability of safe water and sanitation facilities.</p><p> Degree of crowding.</p><p> Health status of population.</p><p> Availability of health care </p><p>services.</p></li><li><p> Deaths from communicable diseases after natural disaster are less common.</p><p> Outbreaks after flooding are better documented than those after earthquakes,volcanic eruptions and tsunamis</p><p> Natural disasters that do not result in population displacement are rarely associated with outbreaks</p><p>A pathogen can be transmitted only if it is present in the environment where the natural disaster occurred </p></li><li><p>Communicable Disease Transmission Risk assessment</p><p>An accurate communicable disease risk assessment is required</p><p>Identify</p><p> Epidemic &amp; endemic disease that are common in the affected area.</p><p> Living conditions of the affected population.</p><p> Availability of safe water and adequate sanitation facilities.</p><p> Nutritional status and immunization coverage.</p><p> Degree of access to healthcare.</p></li><li><p>Prevention /Control</p><p> Hand washing,proper handling of water/food and sewage disposal, Oral rehydration therapy</p><p>(Improved Oral Rehydration salts for ORT)</p><p> Avoid entering contaminated water</p><p> Hepatitis vaccine</p><p> Isolation , proper nutrition-If cause is Streptococcus-polyvalent vaccine (pneumonia)</p><p> Rapid mass vaccination within 72h of initial case report,Vitamin A in children 6 mo to 5 yrs to prevent complications and reduce mortality (Measles)</p></li><li><p>Rapid mass vaccination-meningitis</p><p>Mosquito control, insecticide-treated nets,bedding,clothing</p><p>-malaria</p><p>Mosquito control,isolation of cases,mass vaccination-</p><p>Dengue , Japanese encephalitis,Yellow fever</p></li><li><p>Rapid detection of the infectious agent is essential</p><p>Development of novel diagnostic kits for rapid </p><p>detection of Shigella and E.coli species</p><p>-Department of Biochemistry,University of Madras</p><p>Antibiotic treatment and vaccination for Shigella </p><p>species and other enteropathogens are not always </p><p>successful because they are increasingly resistant to </p><p>antibiotics and possess high antigenic variations.</p><p>We have designed a rapid diagnostic kit and </p><p>alternative therapeutic strategies </p></li><li><p>Preventive Health Measures against the transmission </p><p>of infectious agents related to natural disasters</p><p>Key points listed by WHO</p><p> Keep hands and vessels clean</p><p> Avoid preparing food directly in areas surrounded by </p><p>flood water.</p><p> Separate raw and cooked food.Cook food thoroughly</p><p> Keep food at safe temperatures</p><p> Use safe water</p><p> Appropriate protective clothing to be worn during </p><p>rescue and clean-up operations</p><p> Immunization</p></li><li><p>THANK YOU</p></li></ul>