Zoonotic Diseases of Various Species

1. Zoonotic Diseases of Various Species Note: The images in this presentation are for non-profit, educational use only. Part I

2. What we will cover • We will answer the following questions about each zoonotic disease: • What is it? • How can I get it? • What are the symptoms? • What preventive measures can be taken to avoid acquiring it?

3. Diseases to be discussed: • Q Fever • Orf Disease • E Coli • Campylobacteriosis • Cryptosporidiosis • Giardiasis

4. Q Fever – What is it? • Q fever (query fever) is a zoonotic disease caused by Coxiella burnetii, a species of bacteria that is distributed globally. (1)

5. Q Fever – What is it? • Cattle, sheep, and goats are the primary reservoirs of C. burnetii.  • Infection has been noted in a wide variety of other animals, including other species of livestock and in domesticated pets. (1)  

6. Q Fever – What is it? • Significance for Bioterrorism - Coxiella burnetii is a highly infectious agent that is rather resistant to heat and drying. • It can become airborne and inhaled by humans. • A single C. burnetii organism may cause disease in a susceptible person. • This agent could be developed for use in biological warfare and is considered a potential terrorist threat.  (1)

7. How do I get it? • Organisms are excreted in milk, urine, and feces of infected animals. • During birthing the organisms are shed in high numbers within the amniotic fluids and the placenta.  • The organisms are resistant to heat, drying, and many common disinfectants.  (1)

8. How do I get it? • The bacteria can survive for long periods in the environment.  • Infection of humans usually occurs by inhalation of these organisms from air that contains airborne barnyard dust contaminated by dried placental material, birth fluids, and excreta of infected herd animals.  • Humans are often very susceptible to the disease, and very few organisms may be required to cause infection. (1)

9. How do I get it? • Ingestion of contaminated milk, followed by regurgitation and inspiration of the contaminated food, is a less common mode of transmission.  • Other modes of transmission to humans, including tick bites and human to human transmission, are rare. (1)

10. How do I get it? • In the United States, Q fever outbreaks have resulted mainly from occupational exposure involving veterinarians, meat processing plant workers, sheep and dairy workers, livestock farmers, and researchers at facilities housing sheep. (1)

11. What are the Symptoms? • Only about one-half of all people infected with C. burnetii show signs of clinical illness. • Most acute cases of Q fever begin with sudden onset of one or more of the following: high fevers (up to 104-105° F), severe headache, general malaise,myalgia, confusion, sore throat, chills, sweats, non-productive cough, nausea, vomiting, diarrhea, abdominal pain, and chest pain. (1)

12. What are the Symptoms? • Fever usually lasts for 1 to 2 weeks. • Weight loss can occur and persist for some time. • Thirty to fifty percent of patients with a symptomatic infection will develop pneumonia. • Additionally, a majority of patients have abnormal results on liver function tests and some will develop hepatitis. (1)

13. What are the Symptoms? • In general, most patients will recover to good health within several months without any treatment. • Only 1%-2% of people with acute Q fever die of the disease. (1)

14. What are the Symptoms? • Chronic Q fever, characterized by infection that persists for more than 6 months is uncommon but is a much more serious disease. • Patients who have had acute Q fever may develop the chronic form as soon as 1 year or as long as 20 years after initial infection. (1)

15. What are the Symptoms? • A serious complication of chronic Q fever is endocarditis (inflammation of the inside lining of the heart chambers and heart valves. • Most patients who develop chronic Q fever have pre-existing valvular heart disease or have a history of vascular graft. • Transplant recipients, patients with cancer, and those with chronic kidney disease are also at risk of developing chronic Q fever. • As many as 65% of persons with chronic Q fever may die of the disease.  (1)

16. What are the Symptoms? • The incubation period for Q fever varies depending on the number of organisms that initially infect the patient. • Most patients become ill within 2-3 weeks after exposure. • Those who recover fully from infection may possess lifelong immunity against re-infection. (1)

17. Prevention • Appropriately dispose of placenta, birth products, fetal membranes, and aborted fetuses at facilities housing sheep and goats. • Restrict access to barns and laboratories used in housing potentially infected animals. • Use only pasteurized milk and milk products. • Use appropriate procedures for bagging, autoclaving, and washing of laboratory clothing. (1)

18. Prevention • Vaccinate (where possible) individuals engaged in research with pregnant sheep or live C. burnetii. • Quarantine imported animals. • Ensure that holding facilities for sheep should be located away from populated areas.  Animals should be routinely tested for antibodies to C. burnetii, and measures should be implemented to prevent airflow to other occupied areas. • Counsel persons at highest risk for developing chronic Q fever, especially persons with pre-existing cardiac valvular disease or individuals with vascular grafts. (1)

19. Prevention • A vaccine for Q fever has been developed and has successfully protected humans in occupational settings in Australia. However, this vaccine is not commercially available in the United States. • A vaccine for use in animals has also been developed, but it is not available in the United States. (1)  

20. Recent Outbreak • “Q fever…has shown up in an unusual number of cases this summer in Colorado, health officials say. The source is probably diseased livestock such as sheep or goats, health officials said. The health department has confirmed 13 human cases in the state in 2005…In 2004, there were 3 confirmed cases throughout Colorado…” (2)

21. Review Questions • Q fever is caused by a bacteria called _____ _______.

22. Answer • Coxiella burnettii

23. Question • _________, ________, and ______ are the primary reservoirs for Coxiella burnettii.

24. Answer • cattle, sheep, and goats

25. Question • In the United States, Q fever outbreaks have resulted mainly from _________ _________ involving veterinarians, meat processing plant workers, sheep and dairy workers, livestock farmers, and researchers at facilities housing sheep.

26. Answer • occupational exposure

27. True or False • Drinking non-pasteurized milk is not a concern for contracting Q fever.

28. Answer • false

29. Orf Disease – What is it? • Orf Disease (Contagious Ecthyma) is a parapoxvirus infection that is endemic in many sheep flocks and goat herds throughout the United States. • The disease affects all age groups, although young animals are most often and most severely affected. • Orf produces proliferative, pustular encrustations on the lips, nostrils, mucous membranes of the oral cavity, and urogenital orifices of infected animals.(4)

30. How Do I Get it? • Orf is transmitted to humans by direct contact with virus-laden lesion exudates. • External lesions are not always apparent, so recognition may be difficult.(4) Contagious Ecthyma in a Sheep Muzzle

31. How Do I Get It? • Transmission of the agent by fomites or contaminated animals is possible because of its environmental persistence. • Rare cases of person-to-person transmission have been recorded.(4)

32. Symptoms • The disease in humans is usually characterized by the development of a solitary lesion on the hand, arm, or face. (4)

33. Symptoms • Such lesions are sometimes mistaken for an abscess, but should not be lanced. • Occasionally, several nodular lesions are present, each measuring up to 3 cm. in diameter, persisting for 3-6 weeks, and regressing spontaneously. • Regional adenitis is uncommon. Progression to generalized disease is considered rare.(4)

34. Prevention • Vaccination of susceptible sheep and goats is effective in preventing the disease. • Personnel who handle sheep and goats should be cautioned to wear protective clothing and gloves and to practice good personal hygiene.(4)

35. Review Questions • What does endemic mean when referring to a disease or condition?

36. Answer • Present or usually prevalent in a population or geographical area at all times.

37. True or False • Cases of person-to-person transmission of Orf disease are common.

38. Answer • False - Rare cases of person-to-person transmission have been recorded.

39. Question • ________ of susceptible sheep and goats is effective in preventing the disease.

40. Answer • vaccination

41. E Coli – What is it? • E. coli O157:H7 is one of hundreds of strains of the bacterium Escherichia coli. • Although most strains are harmless and live in the intestines of healthy humans and animals, this strain produces a powerful toxin and can cause severe illness. (3)

42. E Coli – What is it? • E. coli was first recognized as a cause of illness in 1982 during an outbreak of severe bloody diarrhea; the outbreak was traced to contaminated hamburgers. • Since then, most infections have come from eating undercooked ground beef. (3) “Where’s the Beef?”

43. E Coli – How Do I Get It? • The organism can be found on a small number of cattle farms and can live in the intestines of healthy cattle. • Meat can become contaminated during slaughter, and organisms can be thoroughly mixed into beef when it is ground. • Bacteria present on the cow's udders or on equipment may get into raw milk. (3)

44. E Coli – How Do I Get It? • Eating meat, especially ground beef, that has not been cooked sufficiently to kill E. coli can cause infection. • Contaminated meat looks and smells normal. • Although the number of organisms required to cause disease is not known, it is suspected to be very small. (3)

45. E Coli – How Do I Get It? • Among other known sources of infection are consumption of sprouts, lettuce, salami, unpasteurized milk and juice, and swimming in or drinking sewage-contaminated water. (3)

46. E Coli – How Do I Get It? • Bacteria in diarrheal stools of infected persons can be passed from one person to another if hygiene or handwashing habits are inadequate. This is particularly likely among toddlers who are not toilet trained. Family members and playmates of these children are at high risk of becoming infected. (3)

47. E Coli – How Do I Get It? • Young children typically shed the organism in their feces for a week or two after their illness resolves. Older children rarely carry the organism without symptoms. (3)

48. E Coli – How Do I Get It? • Recent outbreaks of E Coli have been linked to petting zoos. • One of these outbreaks originated at the North Carolina State Fair in 2004.

49. E Coli – How Do I Get It? • Health Investigators Determine Cause of E-coli Outbreak – 12/16/04 • RALEIGH – Investigators with the North Carolina Division of Public Health have determined the source of the majority of E.-coli cases during this year’s State Fair, October 15-24. Through extensive environmental testing and genetic fingerprinting, the investigators have linked many of the cases to the Crossroads Farm Petting Zoo. • The final investigation reports 108 likely E.-coli cases of people who had attended the fair and had E.-Coli symptoms, which included diarrhea. Forty-three of those cases were confirmed by lab tests. Thirty-three of those cases had identical genetic fingerprints, and those fingerprints matched positive E.-coli samples from the Crossroads Farm Petting Zoo site. (4)

50. E Coli – How Do I Get It? • Investigators were also able to pin down behaviors that were likely to result in infection by questioning people who were infected and a control sample of people who attended the zoo and matched the age groups of those infected but did not get ill. • This study involved 45 people who were infected and 188 controls. Direct contact with manure was most likely to cause infection. People who had fallen down in manure, touched manure, stepped on manure or had animals jump on them were more likely to be infected. Children who were sucking their thumbs or pacifiers or drinking from a sippy cup while visiting the petting zoo were also more likely to be infected. (4)