BulSU-COM PrevMed Food Poisoning & Infection Control PDF

Community Medicine Week 11 (1st sem.): Food Poisoning and Principles of Infection Control Glenn Nathaniel S.D. Valloso, MD, DPSP Anatomic and Clinical Pathologist BulSU College of Medicine Department of Preventive Medicine and Public Health...

Community Medicine Week 11 (1st sem.): Food Poisoning and Principles of Infection Control Glenn Nathaniel S.D. Valloso, MD, DPSP Anatomic and Clinical Pathologist BulSU College of Medicine Department of Preventive Medicine and Public Health A.Y. 2024-2025 Part 1 Food Poisoning Food Poisoning Definition: Acute illness from contaminated food. Causes: Bacteria, toxins, viruses, or natural poisons. Symptoms: Nausea, vomiting, abdominal cramps, and diarrhea. Pathophysiology of Food Poisoning Non-Inflammatory Type: Cause: Enterotoxins affecting secretory mechanisms in the small intestines. Symptoms: Watery diarrhea without leukocytes. Examples: Vibrio cholera, Escherichia coli, Clostridium perfringens, Staphylococcus species, Giardia lamblia, and various viruses (Adenovirus, Rotavirus, Norwalk virus). Inflammatory Type: Cause: Cytotoxins invading and damaging intestinal mucosa. Symptoms: Bloody diarrhea with leukocytes. Examples: E. coli (enterohemorrhagic and enteroinvasive), Campylobacter jejuni, Vibrio parahaemolyticus, Clostridium difficile, Entamoeba histolytica, Salmonella, Shigella species. Pathogenic Mechanisms in Food-Borne Diseases 1.Toxins Produced in Food Before Consumption: Onset: Rapid (6-12 hours); symptoms primarily affect the upper intestine. Examples: Staphylococcus aureus, Bacillus cereus (emetic toxin), botulism. 2.Toxins Produced After Ingestion: Onset: Delayed (24 hours or more); can cause watery or bloody diarrhea. Examples: Vibrio cholerae, Enterotoxigenic Escherichia coli (watery diarrhea). Shiga toxin-producing E. coli (bloody diarrhea). 3.Pathogens Damaging or Invading the Intestinal Epithelium: Symptoms: Range from watery diarrhea to inflammatory diarrhea or systemic disease. Examples: Cryptosporidium parvum, enteric viruses (watery diarrhea). Salmonella, Campylobacter, Shigella (inflammatory diarrhea). Listeria monocytogenes (systemic disease). Etiologic Agents and Clinical Manifestations of Foodborne Illnesses Gastroenteritis (Vomiting): Common agents: Norovirus, rotavirus, Staphylococcus aureus toxin, Bacillus cereus, heavy metals Non-inflammatory Diarrhea (Watery): Agents: E. coli (ETEC), Giardia, Vibrio cholerae, enteric viruses Inflammatory Diarrhea (Bloody): Agents: Shigella, Salmonella, Campylobacter, E. coli O157 , Yersinia enterocolitica, Entamoeba histolytica Persistent Diarrhea (>14 days): Agents: Cyclospora cayetanensis, Cryptosporidium, Giardia Neurologic Symptoms: Agents: Clostridium botulinum (botulism), organophosphates, scombroid poisoning Systemic Illness (Fever, Weakness, Jaundice): Agents: Listeria monocytogenes, Brucella, Trichinella spiralis, Hepatitis A & E Foodborne Diseases – Impact and Surveillance in the US Annual Impact: 6-81 million illnesses, 9,000 deaths Common pathogens: Listeria, Salmonella, Toxoplasma (1,500 deaths) CDC Statistics (2013): 350 million diarrhea cases annually, 48 million foodborne 125,000 hospitalizations, 3,000 deaths; economic cost: $150 billion Foodborne Diseases – Impact and Surveillance in the US International Comparison: Denmark study: 14.4% of 52,121 cases hospitalized; 1.2% with severe complications (intestinal perforation) High morbidity linked to Listeria, Shiga toxin- producing E. coli, non-typhoidal Salmonella CDC FoodNet Program: Active since 1996 in 10 states; covers 46 million people Campylobacter and Vibrio infections increasing; stable but concerning Salmonella rates Outbreak Data (1998-2008): 13,000 outbreaks, 270,000 illnesses, 9,000 hospitalizations, 200 deaths Food Poisoning Outbreaks in the Philippines Study Findings (Azanza, 2004): Analyzed 60 outbreaks (1995-2004) Common sources: Meat dishes in schools and workplaces Frequent pathogens/toxins: Salmonella, Vibrio, Staphylococcal enterotoxin, paralytic shellfish toxin, histamine Notable Outbreaks: 27 deaths in Philippine schools (2005, Philippine Daily Inquirer) WHO report: Food contamination as a leading global health issue Case Example (Aspillera, 2014): Office worker sickened by contaminated caldereta from a carinderia Incident highlights need for awareness in food safety and preparation Global and Local Concerns: Infected food handlers in all types of food outlets pose risks Foodborne illness affects all socioeconomic levels, with higher impact on impoverished populations Notable Food Poisoning Outbreaks in the Philippines (2005-2011) San Jose Elementary School, Bohol (March 2005): 27 children died, 100 hospitalized Suspected food: "Maruya" (banana fritters) and "Buchi-buchi" Symptoms: Vomiting, diarrhea; cause of death - severe dehydration Immediate rehydration and activated charcoal saved other children Tomas Earnshaw Elementary School, Manila (July 2011): 400 initially hospitalized, later increasing to 680 Symptoms: Vomiting, abdominal pain, diarrhea, nausea Source: Food from school canteen; investigation found lack of chlorine in water and salmonella infection Birthday Party in Calumpit, Bulacan (June 2011): 200 children hospitalized Symptoms: Stomachache, chest pain, diarrhea, vomiting Suspected food: Spaghetti served at the party Morbidity and Mortality in Foodborne Illness Higher Mortality in Elderly: Increased susceptibility due to decreased immunity, low gastric acid, malnutrition Common pathogens: C. perfringens, E. coli, Salmonella, Campylobacter, Staphylococcus Complications: Dehydration as most common complication Potential for electrolyte imbalance and renal failure in severe cases Foodborne Disease Outbreaks Definition: Occurs when two or more people contract the same illness from the same contaminated food Common Settings: Catered events, restaurants, potluck dinners Community outbreaks linked to specific foods (e.g., fish) Significance: Indicates issues in food safety practices Public health investigations aim to control and prevent future outbreaks Common Bacterial Causes of Food Poisoning Staphylococci: Source: Improperly cooked meat, dairy, bakery Symptoms: Vomiting, diarrhea (2-6 hrs post-ingestion) Treatment: Symptomatic and volume replacement Clostridium perfringens: Source: Under-cooked meat, poultry, legumes Symptoms: Abdominal cramps (8-10 hrs post-ingestion) Treatment: Symptomatic, stool culture for confirmation Bacillus cereus: Source: Contaminated fried rice Symptoms: Emetic or diarrheal forms with varied incubation Treatment: Symptomatic Common Bacterial Causes of Food Poisoning Clostridium botulinum: Source: Canned foods, mushrooms, vegetables Symptoms: Paralysis, respiratory issues (1-4 days post-ingestion) Treatment: Antitoxin, respiratory support Enterotoxigenic E. coli: Source: Contaminated water, salads, cheese, meat Symptoms: Vomiting, abdominal cramps (1-2 days post-ingestion) Treatment: Supportive Common Bacterial Causes of Food Poisoning Vibrio cholerae: Source: Contaminated water, food Symptoms: Rice-water stools, severe dehydration Treatment: Fluids, tetracycline Shigella: Source: Potatoes, eggs, lettuce Symptoms: Bloody diarrhea, cramps, fever Treatment: TMP-SMX, ampicillin for severe cases Common Bacterial Causes of Food Poisoning Salmonella: Source: Beef, poultry, dairy Symptoms: Abdominal pain, vomiting (1-2 hrs post-ingestion) Treatment: Antibiotics for systemic infection Listeria monocytogenes: Source: Raw hot dogs, unpasteurized cheese Symptoms: Meningitis, high mortality in elderly and pregnant women Treatment: Supportive care, hydration Common Parasitic and Toxic Causes of Food Poisoning Parasitic Causes: Entamoeba histolytica Source: Contaminated food and water Symptoms: Diarrhea, abdominal cramps, vomiting (12-24 hrs post-ingestion) Treatment: Stool examination, metronidazole or secnidazole Giardia lamblia Source: Contaminated water, fecal-oral transmission Symptoms: Bloody diarrhea, tenesmus (2-3 days post-ingestion) Treatment: Stool examination, metronidazole Common Parasitic and Toxic Causes of Food Poisoning Toxic Fish Poisoning: Paralytic Shellfish Poisoning Source: Bivalve mollusks from coastal areas Symptoms: Numbness, headache, respiratory arrest (30-60 mins post-ingestion) Treatment: Observation, oxygen support if needed Tetradotoxin Poisoning (Puffer fish) Source: Puffer fish (Japan) Symptoms: Paralysis, high mortality risk (10-40 mins post-ingestion) Treatment: Close observation, symptomatic care Scombroid Poisoning Source: Tuna, mahi-mahi, kingfish Symptoms: Allergic reaction, rash, flushing (15-50 mins post-ingestion) Treatment: Antihistamines, H2 blockers, epinephrine Common Parasitic and Toxic Causes of Food Poisoning Other Parasitic Causes: Fascioliasis (Liver Flukes) Source: Infected watercress, consumption of contaminated livestock Symptoms: Hepatomegaly, jaundice, right upper quadrant pain Treatment: Anti-parasitic medications, stool examination for flukes Heavy Metals as Causes of Food Poisoning Mercury: Source: Ingestion of inorganic salts Symptoms: Metallic taste, salivation, thirst, oral discoloration, abdominal pain, vomiting, bloody diarrhea, acute renal failure Treatment: Emesis, lavage, activated charcoal, cathartic; Dimecaprol for acute cases Lead: Source: Chronic exposure Symptoms: Bloody diarrhea, abdominal cramps, tenesmus; may last for a week Treatment: Lead level monitoring; stool examination if parasitic involvement suspected Arsenic: Source: Ingestion of pesticides, industrial chemicals Symptoms: Abdominal pain, watery diarrhea, vomiting, muscle cramps, dehydration; onset 1-12 hrs after ingestion Treatment: Gastric lavage, activated charcoal, Dimecaprol injection, oral penicillamine Viral Cause of Food Poisoning – Hepatitis A Virus Causative Agent: Hepatitis A virus Source of Contamination: Raw shellfish, green onions Clinical Features: Incubation period: 15-50 days Symptoms: Fever, right upper quadrant pain, hepatomegaly, jaundice, vomiting, abdominal pain Diagnosis and Treatment: Serologic testing to confirm virus presence Liver ultrasound for assessment Supportive treatment Steps in Epidemiological Investigation of Foodborne Outbreaks Initiation of Investigation: Team includes sanitation expert, food scientist, veterinarian, ichthyologist, food sanitation engineer Case Identification: Develop case definition based on symptoms, onset, and location Create a map of affected individuals’ locations and activities Data Collection and Analysis: Classify cases by demographics (age, sex, occupation, residence) Conduct interviews with ill and non-ill groups Use statistical methods to identify potential food sources Steps in Epidemiological Investigation of Foodborne Outbreaks Laboratory Confirmation: Blood or stool tests to confirm pathogen Further analysis of implicated food items for contamination details Outcome: Identify contamination source and mechanism Implement prevention measures to reduce future risks Diagnosing Foodborne Diseases Probable Diagnosis: Based on clinical manifestations, food history, and pathogenic mechanism relevance Clinical Manifestations: Common: Nausea, vomiting, fever, abdominal pain, diarrhea Atypical symptoms: Paralysis (botulism, shellfish poisoning), tingling (ciguatera, scombroid), amnesia, meningitis (Listeria) Diagnosing Foodborne Diseases Food History: Key factors: Symptoms, specific food exposure, time interval to onset Detailed History: Duration and type of symptoms, travel history, drug use Indicators: Diarrhea < 2 weeks (typical for foodborne illness) Fever (suggests invasive disease) Bloody/mucus stool (indicates possible large bowel ulceration) Profuse rice-water stool (suggests V. cholerae) Diagnosing Foodborne Diseases Physical Exam: Assess dehydration: Mild: Dry mouth, low sweat/urine output Moderate: Low blood pressure, mottled skin Severe: Shock, confusion, tachycardia Laboratory Tests: Fecalysis, CBC, electrolytes, stool culture Stool pH (lactose intolerance), blood/urine for metals (lead, mercury, arsenic) Management and Diagnosis of Foodborne Illness Initial Assessment: Determine dehydration level to guide treatment Treatment Steps: Correct electrolyte imbalances Administer antibiotics based on causative agent Antibiotic Selection: Tailored to specific pathogen identified Diagnostic Flow Chart: Identifies causes of food poisoning Guides appropriate antibiotic therapy Antibiotic Selection for Foodborne Illness Antibiotic Choice Factors: Based on likelihood of invasive organism and resistance patterns Travel history critical for identifying resistance Indicators of Invasive Disease: Blood in stool suggests invasive infection Fever not a reliable indicator of dysentery Common Treatments: Adults: Fluoroquinolones for traveler's diarrhea Children