Infectious Diseases in the Wilderness

1. Infectious Diseases in the Wilderness Joe Alcock MD MS

2. Introduction • How big is the problem? • Up to 50% of patients develop infection • GI 20-50% • Respiratory 12% • Fever 4% • Depends on: • Where you travel • How long you are in the wilderness • How careful you are in preventing illness

3. Where Do Infections Come From in the Wilderness? • Diseases that you bring with you: • Direct contact: from someone who is ill • Indirect contact: from contaminated food or water • diseases that you carry on your skin or clothes • Most diseases come “into” the wilderness

4. Where Do Infections Come From in the Wilderness? • Diseases that are found in the wilderness • from animals and insects • from contaminated water • from inanimate objects such as soil

5. Prevention of Illness • Knowledge of risks • Proper food handling • Preparation of safe drinking water • Good hygiene principles • Skin protection from injury • Insect precautions • Avoid contact with animals

6. Low health hazard as most trash in contained Disposal of trash is improving Trash

7. Storage difficulties 45-140 degrees: perfect for bacteria Reheat: kill bacteria, spare the toxin Leftover Food

8. Cook only what you eat, don’t save leftovers Utensils: possible contamination risk Boil Clean with bleach solution Leftover Food

9. Fecal Contamination • Four means of fecal pathogen transmission • 1. Direct contact with the feces • 2. Indirect contact with hands that have contacted feces • 3. Contact with insects that have contacted feces • 4. Drinking fecally contaminated water

10. Fecal Contamination • Make a plan to deal with human waste • Deposit waste in a manner to maximize decomposition and minimize chance of: • subsequent discovery by a fellow camper • water contamination • Wash hands • Have soap and disinfectant available

11. Urine • Is usually sterile • Usually urinate away from water sources • Some protected areas request that adventurers urinate directly into the water

12. Food and Water Borne Diseases • Diarrhea and Vomiting • “Stomach flu” • “Food poisoning” • Dangerous in wilderness

13. Food and Water Borne Diseases • Staphylococcus • Bacillus cereus, Clostridium perf. • Giardia • Campylobacter • Cryptosporidium • Salmonella • Enterotoxigenic E. Coli • Norwalk virus

14. Staphylococcus • From hands into food • Multiplies rapidly • Produces toxin

15. Staphylococcus • Symptoms 1-6 hours after ingestion: • Cramps • Vomiting • Diarrhea • Headache • Sweats • Chills

16. Staphylococcus • Found on • Ham • Poultry • Eggs • Pastries • Hands

17. Other food poisoning agents • Bacillus cereus -- grows in soil and is more often found on vegetables • Clostridium perfringens -- is more likely found in inappropriately handled meat or gravy.

18. Giardia • Ubiquitous • Trophozoite and Cyst • Cysts survive in cold water • Carriers: • Beavers • Rodents • Dogs • Cats • Deer • Sheep

19. Giardia • 5-21 day incubation • Source: • Person to person • Untreated surface water

20. Giardia • Diarrhea 89% • Malaise 84% • Flatulence 74% • Foul smelling stools 72% • Abdominal cramping 70% • Bloating 69% • Nausea 68% • Weight loss 64% • Vomiting 26% • Fever 13%

21. Giardia • Diagnosis: • At hospital: O&P, ELISA, DFA • Treatment: • Metronidazole • Quinacrine

22. Cryptosporidium • Causes persistent symptoms in immunocompromised patient • Transmission • Zoonoses: contaminated water • 2-7 day incubation • Symptoms • Diarrhea • Malaise • Abdominal cramping

23. Cryptosporidium • Diagnosis: • O&P, Acid-fast stain, DFA, ELISA • Treatment • None • Paromomycin: if severe

24. Campylobacter • Source: • Untreated water • Undercooked poultry • 2-4 day incubation

25. Campylobacter Symptoms: • Fever headaches • Myalgias • Malaise • Watery/ Bloody diarrhea • Abdominal cramping

26. Campylobacter • Diagnosis: stool culture • Treatment: • Symptomatic • Shorten course with • Erythromycin • Fluoroquinolone

27. Salmonella • Sources: • Raw eggs • Dairy products • Animal feces • Larger dose = worse disease • 2-4 day incubation

28. Salmonella • Symptoms • Diarrhea • sometimes bloody • with fecal WBC’s • Fever • Malaise • Abdominal • Pain

29. Salmonella • Diagnosis: • Stool culture • Treatment: • Fluoroquinolone • Trimethoprim-sulfa • Ceftriaxone

30. Enterotoxigenic E. Coli • Traveler’s Diarrhea • 1-3 day incubation • Symptoms: • Diarrhea • No blood • No Leukocytes • No systemic infection • Abdominal Cramping

31. Enterotoxigenic E. Coli • Different from other E. coli • Adherence • produce heat stable and heat labile enterotoxin

32. Enterotoxigenic E. Coli • Treatment • Symptomatic • Fluoroquinolone • Trimethoprim-Sulfa • Imodium

33. Norwalk virus • Surface water contaminated with human feces or indirect spread from ill person • “Winter vomiting disease” but seen on the Colorado River last summer • May be partially resistant to chlorine • Symptoms: fever, abdominal cramping, vomiting, diarrhea • Send specimens to State Health Dept. • Symptomatic treatment

34. Viruses Short incubation time Very contagious especially with poor hygiene Most common backcountry source of URI Rhinovirus: The common cold Respiratory Infections

35. Respiratory Infections • Streptococcus pyogenes : strep throat and sinusitis, symptoms that would suggest: • Temperature over 100 • Tender cervical lymphadenopathy • Exudative tonsillitis • Lack of nasal congestion and cough • Risk factors: stressful circumstances, close quarters, poor hygiene such as sharing water bottles.

36. Infection of the lung tissue Pneumococcus Mycoplasma Chlamydia Aspiration Fungi -- coccidiomycosis histoplasmosis Respiratory Infections : Pneumonia

37. Respiratory Infections : Pneumonia • Symptoms: • Shortness of breath • Chest pain • Chills • Fever • Sputum production • Productive cough

38. Respiratory Infections : Pneumonia • Treatment: • Specific antibiotics and definitive care required • Evacuate • Doxycyline, Levaquin

39. Problem in wilderness “Dirty” Environment frequent abrasions or breaks in the skin limited treatment Skin Infections

40. Group A strep. Staph. aureus Clostridia perfringens Pasteurella multocida Pseudomonas Bacillus cereus Nocardia Atypical Mycobacterium Sporothrix Schenckii Skin Infections

41. Skin Infections: Group A Streptococcus • Flesh eating bacteria • May erupt within 24 hours • Fulminant infection • Rapid necrosis of skin

42. Skin Infections:Clostridia Perfringens • Potentially life threatening • Requires definitive care: • Evacuate

43. Skin infectionsPasteurella multocida • Lives in the mouth of some animals especially cats and dogs • Rapid onset of symptoms --within 24 hours. • Treatment with Amoxacillin/B-lactam inhibitor

44. Skin Infections: Staphylococcal Aureus • Present on skin or nasal area • Incubation time 3-7 days • Responsible for numerous skin diseases-- boils, furuncles, sties, scalded skin syndrome, etc.

45. Rabies • Transmitted in saliva of infected animals • 100% preventable • 55K deaths • 1-2 in US • Dogs: • USA <5% • Worldwide 90%

46. Rabies • Highly susceptible hosts • Foxes • Coyotes • Wolves • Jackals

47. Rabies • Intermediately susceptible hosts • Skunks • Raccoons • Bats • Raccoons • Mongooses • Monkeys • Woodchucks

48. Rabies • Unlikely hosts: • Rodents • Birds • Reptiles

49. Rabies • Incidence is 3/100,000 in China and India • Incubation 4 days to 19 years • Usually 20 to 90 days • Location of bite determines incubation • Head: 25-48 days • Extremity: 46-78 days • Disease prodrome: 2-10 days

50. Malaise Headache Fever Chills Abdominal pain Vomiting Pain Apprehension Agitation Nervousness Depression Fatigue Anorexia Cough Sore throat Nausea Diarrhea Paresthesias Anxiety Irritability Insomnia Psychiatric Disturbances Rabies: Signs and Symptoms