Zoonosis Lecture lecture notes for Public Health Students
- 1. Lecturer ABDUL MUIZZ MUKTAR University for Development Studies School of Public Health Department of Environmental & Occupational Health EHS 526- Zoonotic Diseases of Humans and Animals
- 2. Zoonosis and other Infectious agents Zoonotic Diseases Types Transmission Prevention of zoonotic diseases “other” Infectious Agents
- 3. What Is Zoonosis? Zoonosis is a contagious disease spread from: animal to human The term “reverse zoonosis” has been used to describe a disease transmissible from: human to animal
- 4. Zoonotic infection types: Infections transmitted directly from animals to humans Vector-borne infections in which an animal or human is infected by the vector Infections in which animals act as a reservoir for disease transmission, including having the potential for contaminating human food and water sources
- 5. How can a zoonotic or infectious disease be transmitted? Airborne Fecal-oral Direct contact Foodborne Arthropod Vector
- 6. Zoonosis and Research Strong potential for animals to infect humans Disrupts research if animals contract infections from humans Examples? ~ 75% of recently emerging infectious diseases affecting humans are diseases of animal origin ~ 60% of all human pathogens are zoonotic or “reverse zoonotic”
- 7. Zoonotic and Infectious Agents Virus’ Bacteria Parasite/Protozoa Fungi Rickettsia Helminthes Zoonotic disease and infectious agents are associated with all lab and field animals!!!
- 8. Viral Diseases Rabies Lymphocytic Choriomeningitis Virus (LCMV) Hanta Virus Hepatitis A, B, C, D, and E Others: Measles (Rubeola) Influenza
- 9. Viral Diseases: What/Who can be infected? Dogs Bats Rodents Humans Rabies X X X X Lymphocytic Choriomeningitis virus X (Hamsters and House mouse!) X Hantavirus X X Hepatitis X X X X Others: Non-Human Primates: transmit Fatal Herpes B to humans, measles Ferrets: Susceptible to human influenza
- 10. Rabies Rabies: most often occurs in wild animals especially skunks, raccoons, bats and foxes ***Raccoon rabies is present in virtually every North Carolina county*** Never handle a bat or any dead animal with your bare hands.
- 11. Lymphocytic Choriomeningitis Virus: LCMV LCMV infections can occur after exposure to fresh urine, droppings, saliva, or nesting materials from infected rodents Transmission may also occur when these materials are directly introduced into broken skin, the nose, the eyes, or the mouth, or presumably, via the bite of an infected rodent Women who become infected with LCMV during pregnancy may pass the infection on to the fetus Infections occurring during the first trimester may result in fetal death and pregnancy termination, while in the second and third trimesters, birth defects can develop Infants infected In utero can have many serious and permanent birth defects
- 12. Hanta Virus Symptoms may develop between 1 and 5 weeks after exposure to fresh urine, droppings, or saliva of infected rodents Universal symptoms: Fatigue, fever and muscle aches, especially in the large muscle groups— thighs, hips, back, and sometimes shoulders Tightness in chest, difficulty breathing
- 13. Bacterial Diseases Tetanus Rat-Bite Fever Leptospirosis Tularemia Campylobacteriosis Salmonella E. coli A mixture of Zoonotic agents and other agents that might be found in the field/water/non-vendor animals
- 14. Dog Rodent Human Field Exposure- no animal contact needed Tetanus X X X Rat Bite Fever X X Leptospirosis X X X Tularemia X X X Campylobacteriosis X Salmonella X Turtles, frogs E. Coli (colibacilosis) X X X X Bacterial Diseases
- 15. Bacterial Disease from the field: “other” infectious disease (Non-zoonotic) Tetanus o Wounds contaminated with dirt, feces, or saliva o Wounds caused by an object puncturing the skin, like a nail or needle (puncture wounds) o Burns
- 16. Rat Bite fever Streptobacillus moniliformis Clinical presentation: Fever Vomiting Headache Muscle pain Joint pain Rash Symptoms usually occur 3- 10 days after exposure to an infected rodent, but can be delayed as long as 3 weeks Within 2-4 days after fever onset, a maculopapular rash with flat, reddened areas with small bumps. One or more joints may then become swollen, red, or painful
- 17. Leptospirosis Humans can become infected primarily through contact with: urine from infected animals water, soil, or food contaminated with the urine of infected animals Leptospirosis may occur in two phases: Phase 1: High fever Headache Chills Muscle aches Vomiting Jaundice Red eyes Abdominal Pain Diarrhea Rash Some infected persons may have no symptoms at all If a second phase occurs, it is more severe; the person may have kidney or liver failure or meningitis
- 18. Tularemia: Not well known Tularemia is a disease of animals and humans caused by the bacterium Francisella tularensis Rabbits, hares, and rodents are especially susceptible and often die in large numbers during outbreaks. Humans can become infected through several routes, including: Tick and deer fly bites Skin contact with infected animals Ingestion of contaminated water Inhalation of contaminated dusts or aerosols
- 19. Tularemia sudden fever chills headaches diarrhea muscle aches joint pain dry cough progressive weakness Pneumonia and chest pain, bloody sputum, have trouble breathing and even sometimes stop breathing. Other symptoms of tularemia depend on how a person was exposed to the tularemia bacteria. ulcers on the skin or mouth, swollen and painful lymph glands, swollen and painful eyes sore throat
- 20. Tularemia
- 21. Salmonella Outbreaks ~ associated with foods Commonly found in turtles, iguanas, other lizards, snakes (asymptomatic carriers) Avoid direct or even indirect contact between reptiles and infants or immunocompromised persons Wash hands with soap after handling reptiles, birds, or baby chicks, and after contact with pet feces Diarrhea caused by bacterial agents
- 22. Diarrhea caused by bacterial agents Campylobacter Common bacterial cause of diarrhea in the United States Most cases occur as isolated, sporadic events, not as part of recognized outbreaks Campylobacter jejuni grows best at 37°C to 42°C, the approximate body temperature of a bird and seems to be well adapted to birds (asymptomatic carriers)
- 23. Diarrhea caused by bacterial agents E. coli Escherichia coli (E. coli) bacteria normally live in the intestines of people and animals. Most E. coli are harmless and actually are an important part of a healthy human intestinal tract. However, some E. coli are pathogenic, meaning they can cause illness The types of E. coli that can cause diarrhea can be transmitted through contaminated water or food, or through contact with animals or persons. People have gotten infected by swallowing lake water while swimming, touching the environment in petting zoos and other animal exhibits
- 24. Parasitic and Protozoal Diseases Giardiasis Cryptosporidiosis Amebiasis Balantidiasis Toxoplasmosis* *Toxoplasmosis is most common in cats (kittens) and New World NHP’s, not covered
- 25. Dogs Rodents Humans Possible Exposure in field- no animal contact needed Giardia X X X X Cryptosporidia (parasite) X X X Ameba X X X Balantidium X X Parasitic and Protozoal Diseases
- 26. Diarrhea caused by protozoal zoonotic agents Giardia Most common non-bacterial cause of diarrhea in the United States Most commonly transmitted via contaminated water Foodborne illness/infection is the most common cause of diarrhea reported to CDC The agents causing the infection may originate from animals or humans These same agents may also be present in feces of research animals in field studies and research primates
- 27. Fungal Diseases Dermatomycosis “Ringworm” Trichophyton mentagrophytes mainly in rodents and mice Microsporum canis mainly in dogs and cats Commonly transmitted FROM humans TO dogs, cats and rodents
- 28. Helminth Infections Roundworm Hookworm Whipworm Common in pets and wild animals Spread by fecal-oral transmission Persist in Soil, transmissible without direct animal contact
- 29. Humans with zoonotic parasites: Cutaneus and ocular migrans
- 30. Arthropods All rodents are negative at commercial vendors but can be infested during transit, or on site Potential “reverse zoonosis” Found on Rats and Mice: Fleas, mites/scabies, lice Found on Cats and Dogs: Fleas, mites/scabies, mange, ticks, lice Found in the Field: Ticks! Mosquitos!
- 31. Ticks in North Carolina
- 32. Tick-Borne Illness: Rickettsial Diseases Lone Star tick: Transmits ehrlichiosis, Southern Lyme (STARI), tularemia, tick paralysis, and possibly Tularemia, Lyme disease and Babesiosis in NC American Dog Tick: Transmits Rocky Mountain Spotted Fever, tick paralysis, tularemia, and possibly ehrlichiosis Deer Tick or Black-legged Tick: Transmits Lyme disease, babesiosis, erhlichiosis, bartonella, and possibly Powassan encephalitis and tick-borne encephalitis (viral)
- 33. Tick-Borne Illness: West Nile Most people are infected between June- September The most effective way to avoid West Nile virus disease is to prevent mosquito bites: Use insect repellents when you go outdoors. Repellents containing DEET, picaridin, IR3535, and some oil of lemon eucalyptus and para- menthane-diol products provide longer-lasting protection. Wear long sleeves and pants from dusk through dawn when many mosquitoes are most active
- 34. Tick Tips: If you remove an attached tick • Save it in a vial of alcohol in the freezer • Write down the date and location (on your body) where it was removed http://www.tic-nc.org/aboutticks.html
- 35. Questions: Do our vivarium animals have any of these zoonotic pathogens? Do Field research animals have any of these pathogens? Do we have any of these pathogens in fields, streams, or woods?
- 36. Animals from Reputable Vendors… Rodents arrive without arthropod infestations, but can easily be infested if humans bring them into the facility Humans can transmit diseases to lab animals Bacteria and fungi can be transmitted between animals and humans if proper PPE and personal hygiene practices are not followed
- 37. Prevention: In the animal facility Controlled access to animal areas Mandatory Personal Protective Equipment (PPE) Air pressure in animal rooms is maintained negative relative to the clean area Personal Hygiene – Hand washing!
- 38. Personal Protective Equipment PPE helps protect you from exposure to zoonotic disease Dedicated facility clothing Long sleeve lab coat Gloves Safety glasses Shoe covers PPE also protects the animals from humans who might be spreading zoonotic agents (reverse zoonosis)
- 39. Zoonotic and Infectious disease prevention: In the Field Field-specific Awareness and Education! Vaccination when possible (e.g. Rabies, Tetanus) Potable water Mosquito and Tick bite prevention Hand-washing / sanitizer Limit exposure to infected species and fecal material
- 40. General Field Safety when working with Animals: Appropriate closed toe footwear Long pants Gloves Sunscreen Hat Safety glasses Cell phone Emergency contact list First aid kit Fire extinguisher in vehicle
- 41. Specific Field Safety when handling North American rodents: Safety glasses Leather gloves Latex gloves Clorox or bleach wipes Disposable bags Fire ant granules
- 42. Zoonosis and other infectious agents summary: Animals can give diseases to You You can give diseases to Animals Minimize your exposure to animal waste in the facility and in the field Be safety conscious when handling any animal Be safety conscious in the field: Mosquitos, ticks, water, soil, and even edible berries can carry infectious disease