* Epidemiology and control of communicable diseases
Infections acquired through gastrointestinal tract* Epidemiology and Control of Diarrheal Diseases
* DEFINITIONSDiarrhea is a condition in which loose, watery stools are passed more often than normal. Dysentery: Presence of blood and/or mucus in stools Persistent Diarrhea: Diarrhea lasting for 14 days or more
* Importance of diarrheal diseases
Diarrheal diseases constitute the greatest single cause of morbidity and mortality in the world. They are the major cause of morbidity and mortality in infants and young children In developing countries they exacerbate problems caused by malnutritionTypes of Diarrhea
** Causes of Diarrhea Bacterial Causes Of Diarrhea
Vibrio cholerae Shigella Escherichia coli Salmonella Campylobacter jejuni Yersinia enterocolitica Staphylococcus* Viral Causes Of Diarrhea
Rotavirus Adenoviruses Viral gastroenteritis is the most common cause of acute diarrhea worldwide. Parasitic Causes OF Diarrhea Entameba histolytica Giardia lambilia Cryptosporidium Isospora* Other Causes Of Diarrhea
Metabolic diseases Hyperthyroidism Diabetes mellitus Pancreatic insufficiency Food allergy Lactose intolerance Antibiotics Irritable bowel syndrome* Mode of Transmission
Most diarrheal causative agents are transmitted by the fecal-oral route Some viruses (such as rotavirus) can be transmitted through air Nosocommial transmission is possible Shigella (the bacteria causing dysentery) is mainly transmitted person-to-person* PERSON-AT-RISK
CholeraShigellosis
Rotavirus
E. coli
Amoebiasis
2 years and above
children below 5 years
infants and children aged 1-2 years
all age groups
Adults
* Cholera
ShigellosisRotavirus
E. coli
Amebiasis
Rice-watery stool Marked dehydration
No fever No abdominal pain
Scanty amount of stool, with blood and mucus Usually no dehydration Moderate to high grade fever Severe abdominal crampswatery Stool ,greenish or yellowish
Mild to moderate dehydration Moderate grade Fever Mild abdominal painWatery stool, Vomiting is common Moderate to severe dehydration Moderate grade fever Mild abdominal pain
Stool is offensive and bulky , with mucus and blood No dehydration Mild grade fever Lower abdominal cramps
Clinical features
ASSESSMENT OF DEHYDRATION
ASSESSMENT OF DEHYDRATION (contd.)
ASSESSMENT OF DEHYDRATION (contd.)* LABORATORY DIAGNOSIS
Stool microscopy Presence of leukocytes (20 or more per high power field and RBC ) suggests invasive diarrhea possibly shigellosis. Stool microscopy also reveals parasitic infections ( trophozoites of parasites) Dark field microscopy of stool for cholera Stool cultures Stool cultures for detecting bacteria like Vibrio cholera, Salmonella, Shigella. ELISA for rotavirus Immunoassays, bioassays or DNA probe tests to identify E. coli strains* Control measures of Diarrheal diseases
WHO recommended the following control measures: Case Management of Acute Diarrhea The General principles of case management are applicable to most cases of acute diarrhea regardless of etiology. it includes:* Rehydration– replacement of the loss of fluid and electrolytesApproximately 2/3 of diarrheal deaths are attributable to dehydration and, therefore preventable by adequate fluid therapy.
* Salts and water can be replaced by: Oral Rehydration Therapy (ORT) or Intravenous fluids. Mild and moderate dehydration can be managed by ORT. Severe dehydration should be treated with IV solution.
COMPOSITION OF ORS
AMOUNT OF SALT LOSS DURING DIARRHEA
ANTIMICROBIAL AGENTS* DIETARY MANAGEMENT Normal food intake, Continue feeding even if severe diarrhea persists. Breastfeeding should be continued throughout the course of diarrhea. Extra protein intake is needed during and after some diarrheal diseases, for example shigellosis. ANTIMICROBIALS according to the type of pathogens and should be chosen according to the sensitivity pattern of the organism. (Most cases are self limited and subside with supportive therapy)
* ANTIDIARRHEAL DRUGS Should be generally avoided.
* Prevention of DiarrheaSafe water and food Hand washing Proper sanitation breastfeeding Immunization Fly control
VACCINES
An oral cholera vaccine is available, which gives immunity to 50-60% of those who take the vaccine, and this immunity lasts only a few months. No vaccines are available against shigellosis A vaccine against rotavirus diarrhea has been available recently .COMPLICATIONS: WATERY DIARRHEA
Dehydration Electrolyte imbalances Tetany Convulsions Hypoglycemia Renal failureCOMPLICATIONS: WATERY DIARRHEA
Dehydration Electrolyte imbalances Tetany Convulsions Hypoglycemia Renal failure