Wild Game And Fish And How To Consume Them Safely, Part 2

General Health, Infectious Diseases, Environmental Health, Healthy Living
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Not all infections associated with game are transmitted through consumption of meat. Some pathogens enter the body during carcass processing, through contact with blood, tissues, and animal fluids, via aerosols, or through a contaminated environment. In these cases, a person may not eat game at all and still become infected.

Symptoms arising from non-foodborne routes of infection

The key feature of non-foodborne infections is a different mechanism of transmission and different symptoms. Heat treatment of meat is irrelevant, and symptoms are often not associated with food intake. For this reason, such infections frequently remain unrecognized.

Main pathogens associated with non-foodborne infection: tularemia, brucellosis, leptospirosis, echinococcosis.

Tularemia (contact with blood, tissues, and aerosols)

  • Sudden fever and chills;
  • Severe weakness and headache;
  • Painful ulcer at the site of contact (cutaneous form);
  • Enlarged lymph nodes;
  • Cough, chest pain, and shortness of breath (aerosol form).

Brucellosis is characterized by a more gradual onset. The main manifestations are undulating fever, night sweats, muscle and joint pain. The disease may become chronic, accompanied by persistent fatigue and joint dysfunction.

Brucellosis (contact with blood, tissues, or raw fibrous membrane of the carcass)

  • Undulating fever;
  • Night sweats;
  • Weakness and muscle pain;
  • Joint pain;
  • Chronic fatigue.

Leptospirosis is associated with contact with water or surfaces contaminated with the urine of rodents or other infected animals. The clinical presentation ranges from a mild flu-like illness to severe liver and kidney involvement.

Leptospirosis (contact with contaminated water or moist tissues)

  • Fever, chills, body aches;
  • Headache and nausea;
  • Pain in the calf muscles;
  • Liver dysfunction (elevated ALT, AST, bilirubin);
  • Signs of kidney damage (creatinine, urea).

Echinococcosis does not manifest immediately. Parasite eggs enter the body orally, usually via contaminated fur or soil. Symptoms develop slowly, sometimes months or years later, and depend on the location of the cyst.

Echinococcosis (contact with fur or soil contaminated with eggs)

  • Asymptomatic period for months or years;
  • Discomfort or heaviness in the right upper quadrant (with liver involvement);
  • Cough or chest pain (with lung involvement);
  • Allergic reactions in case of cyst rupture.

These non-foodborne mechanisms require separate attention, as during hunting and carcass processing a person may receive significant exposure to pathogens even without consuming the meat. When unclear symptoms appear, it is important to consider the fact of contact with blood, tissues, animal fluids, or a moist contaminated environment.

Who is at particular risk from eating poorly cooked game

Although infection is possible in any person, there are groups in whom even mild infections from game run a more severe course and lead to complications more quickly.

  • Pregnant women. Toxoplasma can affect the fetus even when the mother has no symptoms. Undercooked game is категорically contraindicated during pregnancy;
  • Children. They develop dehydration, electrolyte disturbances, and acute reactions to parasitic and bacterial infections more rapidly. Even a small amount of poorly cooked meat can cause severe symptoms;
  • Older adults. A weakened immune response and comorbid conditions increase the risk of involvement of the heart and respiratory muscles in trichinellosis and other parasitic infections;
  • People with immunodeficiency. Patients on immunosuppressive therapy, after transplantation, with Lyme disease, with HIV, or autoimmune diseases. In these individuals, toxoplasmosis and sarcocystosis are more severe, and bacterial infections become systemic more quickly;
  • Patients with liver disease. Hepatitis E associated with undercooked wild boar or deer liver may have a severe course and rapidly lead to worsening liver function;
  • Hunters and people preparing game in field conditions. Insufficient cooking, cross-contamination, and lack of temperature control make this group particularly vulnerable.

Awareness of belonging to a risk group helps to recognize the problem in time, avoid undercooked game, and seek medical care at the first symptoms.

Prevention and factors determining the safety of consuming meat from wild animals

The safety of game depends not on the “recipe” but on the conditions under which the meat is prepared. Even high-quality meat becomes dangerous if it is impossible to ensure even heating, cleanliness of tools, and separation of raw and cooked products. It is these limitations, rather than the game itself, that create the primary risk.

When cooking in field conditions, it is impossible to accurately control the internal temperature of the meat. A piece may look cooked on the outside but remain raw inside. Real safety is achieved only by dividing the meat into small portions and fully heating it to an internal temperature of at least 71-75 °C.

Freezing does not make game safe. Many parasites common in northern regions remain viable after freezing. Carcass processing is also associated with a high risk due to contact with blood, tissues, and internal organs, as well as the inability to properly wash hands, knives, and surfaces in field conditions.

Storage of harvested game affects only bacterial growth but does not protect against parasites. When kept at moderate temperatures, bacteria actively multiply, so the carcass should be cooled as quickly as possible and not left at room temperature. This reduces bacterial load but does not replace proper heat treatment.

The liver of wild animals requires special attention. It must be fully cooked with no pink center, as the liver of wild boar and deer is the primary food source of viral hepatitis E.

All these factors show that stable sanitary control cannot be ensured in natural conditions. Therefore, undercooked game is one of the highest-risk foods, especially when prepared over an open flame. It is also important to note that animals such as muskrat and beaver can be carriers of Leptospira and tularemia; therefore, their carcass processing should not be done near bodies of water, and water from natural sources should not be used to rinse the carcass.

When preparing dried meat (jerky), simple drying without prior heating is unsafe. A more reliable approach is to first heat thinly sliced meat to an internal temperature of at least 71 °C and only then dry it.

Key reasons why game is difficult to make safe in field conditions

  • Uneven heating of meat due to dense structure, bones, and large cuts;
  • The effect of wind, humidity, and unstable fire on cooking temperature;
  • Lack of a thermometer, making it impossible to assess internal doneness;
  • Limited sanitary conditions, increasing the risk of cross-contamination;
  • Contact with animal blood and tissues without protective equipment.

It is precisely the combination of these factors that makes game a high-risk product when it is insufficiently cooked or processed without sanitary measures.

Conclusion

Game is not a safe product by default. Wild animals serve as natural carriers of parasites, bacteria, and viruses that rarely cause illness in the animals themselves but can lead to severe infections in humans. The risk is determined not by the “naturalness” of the meat and not by its external appearance, but by the specific route through which the infection enters the body.

The danger is associated with concrete situations: consumption of insufficiently processed meat or organs, contact with blood and internal organs during carcass processing, inhalation of aerosols, and cross-contamination of hands, knives, and surfaces. Without understanding these routes of transmission, risk is often assessed incorrectly, and the cause of illness remains unrecognized.

The complexity of these infections lies in the fact that symptoms often do not appear immediately. They may develop days or even weeks after exposure, when a person no longer associates their condition with game. This is precisely why information that a person consumed game or participated in carcass processing can be decisive for making the correct diagnosis.

If treatment begins late, the infection may progress to a severe form with involvement of muscles, the heart, the liver, or the nervous system. In such cases, prolonged loss of work capacity, disability, and, in some situations, death are possible. Risks are particularly high for pregnant women, children, older adults, and people with weakened immunity or liver disease.

For hunters, outdoor enthusiasts, and anyone who comes into contact with wild animals, understanding infectious risks is a matter of basic safety. Careful attention to symptoms and explicitly informing a physician about consumption of game or contact with a carcass can prevent severe and irreversible consequences.

Appendix 1. Key infections associated with game and fish

Trichinella spp

  • Source: bear; wild boar; caribou; walrus; seal;
  • Route of transmission: undercooked meat; freezing does not provide protection;
  • Incubation: 1-4 weeks;
  • Key symptoms: fever; pronounced muscle pain; eyelid edema; weakness; night sweats;
  • Dangerous complications: myocarditis; myositis; involvement of respiratory muscles; neurological disorders; chronic weakness;
  • Clinical markers (clue): eosinophilia; CK↑; CRP↑;
  • Risk: high in severe disease and delayed treatment; fatal outcomes possible.

Toxoplasma gondii

  • Source: deer; moose; wild boar;
  • Route of transmission: undercooked meat; contact with blood during carcass processing;
  • Incubation: 5-23 days;
  • Key symptoms: prolonged low-grade fever; weakness; muscle pain; enlarged lymph nodes;
  • Dangerous complications: in pregnant women - fetal damage; in immunodeficient patients - brain and eye involvement;
  • Risk: low in healthy individuals; high in immunocompromised patients.

Sarcocystis spp

  • Source: deer; moose;
  • Route of transmission: undercooked meat;
  • Incubation: intestinal form - hours to days; muscular form - days to weeks;
  • Key symptoms: vomiting; diarrhea; muscle pain; pronounced weakness;
  • Complications: prolonged muscle weakness;
  • Risk: fatal outcomes are extremely rare.

Taenia spp. (taeniasis / cysticercosis)

  • Source: wild boar; deer;
  • Route of transmission: undercooked meat;
  • Incubation: weeks to months;
  • Key symptoms: abdominal pain; bloating; weight loss;
  • Dangerous complications: in certain species - cysticercosis (organ and CNS involvement);
  • Risk: low in intestinal form; significantly higher with brain involvement.

Diphyllobothrium latum (fish tapeworm)

  • Source: freshwater fish;
  • Route of transmission: raw / undercooked fish;
  • Incubation: 3-6 weeks;
  • Key symptoms: chronic fatigue; dizziness; symptoms of vitamin B12 deficiency;
  • Dangerous complications: irreversible neurological disorders;
  • Risk: low mortality; risk of disability with delayed diagnosis.

Anisakis spp

  • Source: marine fish;
  • Route of transmission: raw / lightly salted fish;
  • Incubation: 1-12 hours;
  • Key symptoms: sharp stomach pain; vomiting; allergic reactions;
  • Dangerous complications: anaphylaxis; chronic allergic reactions;
  • Risk: potentially fatal in severe allergic reactions.

Brucella spp

  • Source: wild boar; deer; bison;
  • Route of transmission: meat; contact with blood; aerosols during carcass processing;
  • Incubation: 1-4 weeks;
  • Key symptoms: undulating fever; night sweats; joint pain; pronounced fatigue;
  • Dangerous complications: endocarditis; spinal involvement; chronic disease course;
  • Risk: moderate without treatment; high with endocarditis.

Acute bacterial intestinal infections (Salmonella / Campylobacter / Yersinia)

  • Source: wild boar; bear; wild birds;
  • Route of transmission: undercooked meat; cross-contamination;
  • Incubation: 6-72 hours;
  • Key symptoms: diarrhea; vomiting; dehydration;
  • Dangerous complications: sepsis; reactive arthritis; severe dehydration;
  • Risk: increased in children, older adults, and debilitated patients.

Francisella tularensis (tularemia)

  • Source: hares; rabbits; beavers; muskrats;
  • Route of transmission: aerosols; contact with tissues; bites;
  • Incubation: 3-5 days;
  • Key symptoms: fever; ulcers at the site of contact; enlarged lymph nodes;
  • Dangerous complications: pneumonia; sepsis;
  • Risk: moderate without treatment.

Leptospira spp

  • Source: rodents; beavers; muskrats;
  • Route of transmission: contaminated water; contact with urine;
  • Incubation: 2-26 days;
  • Key symptoms: fever; severe pain in leg muscles; jaundice;
  • Dangerous complications: severe liver and kidney damage; respiratory failure;
  • Risk: high in severe forms.

Hepatitis E (zoonotic)

  • Source: wild boar; deer;
  • Route of transmission: undercooked liver;
  • Incubation: 2-8 weeks;
  • Key symptoms: fatigue; jaundice; pain in the right upper quadrant;
  • Dangerous complications: acute liver failure;
  • Risk: very high in pregnant women and patients with liver disease.

Appendix 2: Animal → infections → routes of transmission

Animal Infections Routes of transmission
Bear Trichinella nativa; Salmonella; Yersinia; Campylobacter Undercooked meat; contact with blood during carcass processing; cross-contamination
Wild boar Trichinella; Toxoplasma; Taenia; Brucella; Salmonella; Hepatitis E Undercooked muscle meat; undercooked liver; contact with blood; aerosols; cross-contamination
Deer Toxoplasma; Sarcocystis; Taenia; Brucella (rare); Hepatitis E (rare) Undercooked meat; contact with blood; contamination of tools
Moose Sarcocystis; Toxoplasma; intestinal bacteria Undercooked muscle meat; contact with internal organs; cross-contamination
Caribou / reindeer Trichinella nativa; Toxoplasma; Sarcocystis Insufficient heating of large cuts; contact with blood
Walrus / seal Trichinella nativa Undercooked meat; raw/fermented products
Bison Brucella; intestinal infections Contact with blood; undercooked meat; contamination of knives
Hare / rabbit (wild) Tularemia; Toxoplasma (rare) Aerosols during opening; contact with blood; skin micro-injuries; via meat - toxoplasmosis only
Muskrat / beaver Tularemia; Leptospira; intestinal bacteria Contact with tissues; aerosols; contaminated water
Duck / goose / wild birds Salmonella; Campylobacter; Yersinia Undercooked meat; cross-contamination
Fish (freshwater) Diphyllobothrium latum Raw/undercooked fish; insufficient freezing; light salting
Fish (marine) Anisakis Raw/marinated/lightly salted fish; insufficient heating

Appendix 3. Symptom → possible infection → animals → route of transmission

Symptom Possible infection Animals Route of transmission
Fever (acute or undulating) Trichinella; Brucella; Tularemia; Leptospira; acute bacterial infections Bear; wild boar; deer; rabbit; beaver; muskrat; wild birds Undercooked meat; contact with blood/tissues; aerosols; contaminated water
Muscle pain Trichinella; Toxoplasma; Sarcocystis; Leptospira Bear; wild boar; deer; moose; caribou; beaver; muskrat Undercooked meat; contact with tissues during carcass processing
Eyelid edema Trichinella Bear; wild boar; caribou Undercooked meat; large dense cuts
Severe fatigue, weakness Toxoplasma; Brucella; Diphyllobothrium (B12 deficiency); Hepatitis E Deer; moose; wild boar; freshwater fish Undercooked meat; liver; raw fish
Prolonged low-grade fever (37-37.8 °C) without clear cause Toxoplasma; Trichinella (latent stage); Brucella Deer; moose; wild boar; bear Undercooked game; contact during carcass processing
Abdominal pain Taenia; Diphyllobothrium; acute bacterial infections; Anisakis Wild boar; deer; freshwater and marine fish Undercooked meat; raw/marinated fish; cross-contamination
Acute vomiting and diarrhea Salmonella; Campylobacter; Yersinia; Sarcocystis (intestinal form); Anisakis Wild boar; bear; wild birds; fish Undercooked meat; raw fish; improper carcass processing
Pain with eye movement Trichinella Bear; wild boar; walrus; caribou Undercooked meat
Night sweats Brucella; Trichinella Wild boar; deer; bear Undercooked meat; contact with blood/aerosols
Enlarged lymph nodes Toxoplasma; Tularemia Deer; moose; rabbit; hare; beaver Contact with blood; aerosols; less often via meat
Jaundice Hepatitis E; Leptospira Wild boar; deer; beaver; muskrat Undercooked liver; contaminated water
Symptoms of vitamin B12 deficiency (numbness, weakness) Diphyllobothrium latum Freshwater fish Raw/undercooked fish
Acute stomach pain 1-12 hours after fish Anisakis Marine fish Raw/lightly salted fish
Rash, allergic reactions after fish Anisakis (allergic form) Marine fish Allergic reaction to the parasite
Severe weakness + thirst (dehydration) Acute intestinal infections Wild boar; bear; birds Undercooked meat; cross-contamination
Severe pain in leg muscles Leptospira Rodents; beaver; muskrat Contaminated water; contact with urine
Skin ulcers + fever Tularemia Hare; rabbit; beaver; muskrat Contact during carcass processing; aerosols; bites

Health Canada. Safe internal cooking temperatures. Ottawa (ON): Health Canada; 2023.

Sparaciari FE, Firth C, Karlsson EA, Horwood PF. Zoonotic disease risk at traditional food markets. PLoS Pathog. 2024;20(1):e12363201. PMID: 40699134.
https://pubmed.ncbi.nlm.nih.gov/40699134/

United States Department of Agriculture (USDA). Safe minimum internal temperatures chart. Washington (DC): USDA; 2023.

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