Diarrheal Diseases and Dysenteries Community Handout PDF

DIRRHEAL DISEASES AND DYSENTERIES  Definition Diarrhea means frequent evacuation of loose stool. Gastroenteritis is not a single symptom but a complex of symptoms typically acute diarrhea and vomiting. Summer diarrhea is used to describe sporadic cases or outbre...

DIRRHEAL DISEASES AND DYSENTERIES  Definition Diarrhea means frequent evacuation of loose stool. Gastroenteritis is not a single symptom but a complex of symptoms typically acute diarrhea and vomiting. Summer diarrhea is used to describe sporadic cases or outbreaks of diarrheal diseases in hot season. Winter diarrhea or viral diarrhea is repeatedly used to describe diarrheal disease without identifiable bacterial or parasitic cause. Traveler’s diarrhea is affecting persons who newly arrived to a foreign country.  Definition Bacillary dysentery is used to describe a diarrheal illness with fever, abdominal pain and blood and mucous in the stool. Amoebic dysentery is manifested by abdominal pain and bloody diarrhea usually without fever. Public health importance Diarrhea is the most frequent health problem among infants and young children in Egypt. It is responsible for about one third of deaths in the first two years of life.  Epidemiology It varies according to causative organism 1- Person distribution: Age: Most common in young children due to partial immunity and incidence falls with increasing age. Children less than 5 years of age experience two episodes of diarrhea per year. Sex: No sex difference Breast feeding: incidence is significantly lower among breast fed babies. Weaning: Faulty weaning leads to increase incidence of diarrhea. This may be due to contamination of food or food allergy. Diarrhea & malnutrition: malnourished babies are more prone to get diarrhea and develop diarrhea- precipitated malnutrition (vicious circle).  Epidemiology 2- Time distribution: Diarrheal diseases have seasonal variation being more frequent in summer especially in developing countries. High temperature decreases stomach acidity which acts as a natural immunity against enteropathogens.  Epidemiology 3- Place distribution: Incidence of diarrhea is inversely related to general hygienic standards especially water and food sanitation and presence of flies. It is more common in developing countries and in tropical and subtropical areas. In Egypt it is more frequent in slum areas and semi-urban areas than rural and urban areas.  Epidemiology 4. Reservoir :It varies according to the causative organism 5. Mode of transmission: Mainly through ingestion of contaminated food, water and drinks and rarely person to person.  Prevention and Control A- Preventive measures: I. General measures: See guidelines for prevention of food borne infections II. Specific measures: Specific immunization as cholera vaccine, Rota virus vaccine and E.coli vaccine in the near future.  Prevention and Control B- Control measures: Control of patients, contacts and the immediate environment: 1) Report to local health authority: Obligatory report of epidemics. 2) Isolation: Enteric precautions for known and suspected cases. 3) Concurrent and terminal disinfection: Of all fecal discharges and soiled articles. 4) Investigation of contacts and source of infection. 5) Specific treatment: ORT (Fluid Replacement Therapy)  Diarrheal diseases control program in Egypt: The National Diarrheal Diseases control program in Egypt helped in decreasing infant mortality rates. Oral rehydration prevents or cures dehydration with few exceptions (severe dehydration). Other medicines like antibiotics, antidiarrheals and antiemetics do not do anything for dehydration. IV rehydration is usually needed in severe dehydration because of shock or coma.  General guidelines for prevention of foodborne infections Prevention of foodborne infections is based on: - access to safe water and - proper sanitation as well as - adhesion to safe food handling practices.  General guidelines for prevention of foodborne infections 1) Educate the public regarding the importance of hand washing and provide suitable handwashing facilities, particularly for food handlers and attendants involved in the care of patients and children.  General guidelines for prevention of foodborne infections 2) Dispose of human feces safely and maintain fly-proof latrines. Where culturally appropriate encourage use of sufficient toilet paper to minimize finger contamination... 3) Dispose of feces by burial at a site distant and downstream from the source of drinking-water.  General guidelines for prevention of foodborne infections 4) Protect, purify and chlorinate public water supplies, provide safe private supplies, and avoid possible backflow connections between water and sewer systems. 5) For individual and small group protection, and during travel or in the field, treat water chemically or by boiling.  General guidelines for prevention of foodborne infections 6) Control flies by screening and use of insecticidal baits and traps or, where appropriate, spraying with insecticides. 7) Control fly-breeding through frequent garbage collection and disposal and through fly control measures in latrine construction and maintenance.  General guidelines for prevention of foodborne infections 8) Use strict cleanliness in food preparation and handling; refrigerate as appropriate. Pay particular attention to the storage of salads and other foods served cold. These provisions apply to home and public eating places. 9) If uncertain about sanitary practices, select foods that are cooked and served hot, and fruit peeled by the consumer.  General guidelines for prevention of foodborne infections 10) Enforce suitable quality-control procedures in industries that prepare food and drink for human consumption. Use chlorinated water for cooling during canned food processing. 11) Limit the collection and marketing of shellfish to supplies from approved sources. Boil or steam (for at least 10 minutes) before serving.  General guidelines for prevention of foodborne infections 12) Pasteurize or boil all milk and dairy products. Supervise the sanitary aspects of commercial milk production, storage and delivery. 13) Encourage breast-feeding throughout infancy; boil all milk and water used for infant feeding.  Food Safety Food safety refers to the conditions and practices that preserve the quality of food to prevent contamination and foodborne illnesses. The conditions that favor the growth of most foodborne microorganisms (except viruses) can be remembered by the acronym FAT-TOM.  Food Safety Food To grow, microorganisms need nutrients, specifically proteins and carbohydrates. These proteins are commonly found in foods such as meat, poultry, dairy products, and eggs.  Food Safety Acidity Microorganisms typically do not grow in foods that are highly acidic or highly alkaline. Pathogenic bacteria grow well in foods with a pH between 4.6 and 7.5. 0. Foods with a pH higher than 7.0 do not typically support the growth of foodborne microorganisms.  Food Safety Temperature Most foodborne microorganisms grow well between the temperatures of (5°C to 60°C). This range is known as the temperature danger zone. Exposing microorganisms to temperatures outside the danger zone does not necessarily kill them. Refrigeration temperatures, for example, may only slow their growth. Bacterial spores can often survive extreme heat and cold.  Food Safety Time Microorganisms need sufficient time to grow. Bacteria can double their population every 20 minutes. If contaminated food remains in the temperature danger zone for four hours or more, pathogenic microorganisms can grow to levels high enough to make someone ill. Prepare food as close to serving as possible.  Food Safety Oxygen Most microorganisms that cause foodborne illness can grow with (aerobic) or without (anaerobic) the presence of oxygen.  Food Safety Moisture Most foodborne microorganisms grow well in moist foods. The amount of moisture in a food is called its water activity (aw). Water activity is measured on a scale from 0 through 1.0, with distilled water having a water activity of 1.0. Potentially hazardous foods typically have a water activity of 0.85 or above Epidemiology  Hepatitis A Epidemiology  Hepatitis A Epidemiology Epidemiology Developed countries Developing countries Infection occurs in Infection occurs early adolescents & adults in life Acute viral hepatitis No or few symptoms  Epidemiology in Egypt The infection is endemic in rural areas, with the prevalence of HAV IGg antibodies (indicating past infection) at almost 100%. However, in Cairo, the prevalence differs according to the socio-economic class, with children in the lower socio-economic class having a prevalence rate of IgG of almost 90%, while it is only 50% in higher socio- economic class.  Hepatitis A Prevention Active General General Hygiene Specific Immunization measures measures Safe water supply Passive Immunization NOTE: Food handlers who are ill and certainly those with hepatitis A or unexplained jaundice should be restricted from work.  Hepatitis A Active immunization Types of vaccines: formalin-inactivated viral particles. 2 doses (6-12 months apart) Duration of immunity: Over 95% of healthy adults develop anti-HAV antibodies within a month after receiving a single dose of the vaccine. Protection from vaccination is sustained for 10 or more years Timing: Travelers to HAV endemic regions should receive it 1 month before departure. post-exposure prophylaxis.  Hepatitis A B- Control measures I. Measures to cases 1. Report to local health authority 2. Isolation: contact precautions should applied during the first 2 weeks of illness  Hepatitis B Infectious agent HBV DNA virus 3 main antigens: core(c), envelope (e), surface (s) (s): infectious –acute/chronic (e): highly infectious- monitor ttt (cAb): acute/chronic (IgM-HBcAb): acute past 6 months HBsAg Prevalence 8% - High 2-7% - Intermediate