Are we prepared for a Cholera Epidemic in Jamaica? Dr. Homero Silva Professor Public Health and Climate Change School of Public Health UTECH

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1 Are we prepared for a Cholera Epidemic in Jamaica? Dr. Homero Silva Professor Public Health and Climate Change School of Public Health UTECH

2 VIBRIO CHOLERAE DESCRIPTION IT IS AN ANAEROBIC FACULTATIVE BACTERIA, GRAM-NEGATIVE, IT HAS MOBILITY BY A FLAGELLUM OF 1.5 m a 3 m OF LENGTH AND 0.2 m WIDE.

3 CLASSIFICATION VIBRIOCIDAE FAMILY Vibrio GENUM VIBRIO CHOLERAE: SEROGROUP O1 BIOTYPES: CLASIC EL TOR SEROTYPE: INABA - OGAWA - HIKOJIMA SOMATIC ANTÍGEN: AC AB ABC

4 Cholera in Haiti 09 Jan ,012 Cases and 3,790 Deaths 29 May ,066 cases and 5,337 deaths.

5 Evolution Cholera in Haiti

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7 Attack Level Asymptomatic 75% Light Symptoms 18% Ambulatory Care 5% Hospitalization 2%

8 Favourable Conditions for Vibrio Development and Survival Temperature ( o C) Growing Optimum ph 6.4 to 9.6 Nutrients Carbon Organic Compounds (BOD) Nitrogen (NO3) Resistance to Sodium Chloride Concentration < 4%

9 Survival Time Cholera Water Sea Water/Estuaries Sewage Soil Crops Milk (Refrigerator) b Meat (Refrigerator) b Survival times of excreted pathogens in the environment at C a Fish and aquatic products(refrigerator) b Fresh Vegetables(Room Temperature) b Glass, porcelain, plastic and metal (Room Temperature) b Cutting board and cloth b <30 but usually <10 days Years <30 but usually <10 days <20 but usually <10 days <5 but usually <2 days 2 to 4 weeks 1 week 1 to 3 weeks 1 to 5 days Less than 4 days Long time a WHO (1 989) as summarized from Feachem et al. (1983). b Symptoms of vibrio cholerae,

10 Cholera in Fresh Water In regard to cholera in fresh water environments, V. cholerae has been found to concentrate on the surface of the water hyacinth, and Lemna minor, a common duckweed found in freshwater environments. Temperature and Nutrients have been found are the major factors governing the distribution of cholerae

11 Ecology of Cholera Survival and Development Pathogenic vibrios are known to be associated with zooplankton such as copepods with chitin exoskeletons and with shellfish, including crabs, shrimp, and crayfish. Vibrio cholerae is part of the natural flora of the gut of these animals and has a powerful chitinase that enhances its growth on the surfaces of plankton and shellfish.

12 Ecology of Cholera Survival and Development Vibrio cholerae will survive in seawater for months or years The bacterium can be transported by ocean currents over very long distances. Work done with phytoplankton, including blue-green algae, suggests that pathogenic vibrios may survive on both zooplankton and phytoplankton in the aquatic environment, but zooplankton act as amplifiers, increasing the numbers to those sufficient to trigger an epidemic.

13 Ecology of Cholera

14 Common Sources of Infection Drinking water that has been contaminated at its source or during storage, and ice made from contaminated water. Food contaminated during or after preparation. e.g. milk, cooked rice, lentils, potatoes, beans, eggs, and chicken. Seafood. Particularly shellfish, taken from contaminated water and eaten raw or insufficiently cooked. Fruit and vegetables grown at or near ground level and fertilized with night soil, irrigated with water containing human waste, or "freshened" with contaminated water, and then eaten raw.

15 The Risks People and Goods movement Malaria outbreaks and migration Sea Currents Water Food Hygiene Conditions

16 Sea Currents

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18 Drinking Water In the rural areas only 65% of the population has piped water, and 13.1% rely on non-improved water sources, ranging from river/ponds, unimproved wells, Typhoid outbreaks in the past

19 Results of Monitoring For the period October to December 2010 one hundred and thirty five (135) Sewage Treatment Plants (STPs) representing approximately 82% of the one hundred and sixty five (165) plants selected for monitoring were sampled.

20 Results of Monitoring The overall percentage of STPs satisfactory is sixty two and three tenth (62.3)%

21 Results of Monitoring NWC 58.3% Hotels 75.0% Private (excluding Hotels) 63.6% Hospitals and Health Centers 37.5% Other government 66.7%

22 NWC STPs No Plants Flowrate (MLD) % Total TYPE OF TREATMENT STABILIZATION PONDS OXIDATION DITCH CONTACT STABILIZATION EXTENDED AERATION AERATED LAGOONS SEPTIC TANK PRIMARY PLUS CL

23 Statistical Analysis of Samples Analyzed by Environmental Health Laboratory No Meeting Standard Parameter Number of Plants Mean Value (mg/l) Total Flowrat e (MLD) Number Plants Flowrat e (MLD) % Flowrat e Chlorine Fecal Coliform BOD TSS Total Phosphates Total Nitrates

24 SWTP Effluent Quality Fecal Coliforms

25 SWTP Effluent Quality BOD 5

26 SWTP Effluent Quality Nitrogen

27 SWTP Effluent Quality Total Suspended Solids

28 Fecal Coliform Quality in Coastal Areas

29 Agricultural Areas Vs SWTPs

30 Fecal Coliform Quality in Rivers

31 Jamaica Coastal Deterioration Coastal waters have been progressively deteriorating for a number of years. Eutrophication has become a general phenomenon in the past decade. Eutrophication has been so serious that many reefs which formerly had more than 95% live coral cover are now more than 95% algae covered. Overgrowth of reef corals and "good" sandproducing algae by "bad" fleshy algae took place at different times in different places.

32 Progress of Coral Reef Affectation Area Year Kingston 1950 and 1960 Montego Bay and Ocho Rios 1970 Rio Bueno to Runaway Bay 1980 Negril and parts of Western Jamaica 1990

33 Recommendations Strengthen Surveillance Water, wastewater discharges, hospitals WWTP, Raw agricultural products, fish industry, patients, etc. Improve O&M Sewage Treatment Plants Training operators Reacconditioning Disinfection of water Home treatment Safe excreta Disposal Emergency latrines Construction of new in-situ technologies (latrines, septic tanks Massive Public Education Ensure food safety Cooked food Less raw food Shelfish Food street vending

34 Thanks