2/6/05
STUDENT HANDOUT
SURVIVAL MEDICINE
TERMINAL
LEARNING
OBJECTIVE
In a survival situation,
and given a survival kit, maintain individual or group health
standards, and apply survival medicine techniques and procedures, in
accordance with the references. (Chap 14 )
ENABLING LEARNING OBJECTIVES
(1) Without the aid of references, list in writing the requirements to maintain health, in accordance with the reference. (Chap 14 a)
(2) Without the aid of references, list the in writing the environmental injuries, in accordance with the reference. (Chap 14 b)
(3) Without the aid of references, define in writing the definition of hypothermia, in accordance with the reference. (Chap 14 c)
(4) Without the aid of references, list in writing the general considerations for medevac procedures, in accordance with the reference. (Chap 14 d)
(5) Without the aid of references, execute preventive measures against wildlife diseases, in accordance with the reference. (Chap 14 e)
OUTLINE
1. REQUIREMENTS TO MAINTAIN HEALTH. Maintenance of health is the first step in preventing injuries. The three requirements are: (Chap 15 a)
A. WATER
(1) A person can not survive without water for more than a few days. Your body loses water through normal body processes (sweating, urinating, and breathing). During normal activity the kidneys excrete 1 to 2 quarts of water per day and a person evaporates . 5 to quart per day. Other factors, such as heat exposure, cold exposure, intense activity, high altitude, burns, or illness, can cause your body to lose more water. Water intake is critical in preventing illness.
B. FOOD
(1) The body can live several weeks without food. However, without an adequate supply to stay healthy your mental and physical capabilities will deteriorate rapidly. Food supplies the body with the necessary nutrients and energy to survive.
(2) Food sources are plants, animals, and fish.
(a) Fiber. Fiber prevents irritable bowel syndrome. In the Falklands campaign the British had a major constipation and diarrhea problem. This was largely caused by dehydration and a low fiber diet. Grasses and pine needles are a good source of dietary fiber.
(b) Vitamins. Vitamins are essential to metabolic functioning of the body and cold weather compounds this function. Our bodies cannot make vitamins so we must provide them in our diet. Most edible plant life contains many different vitamins. Associated illnesses from long term deficiency are Scurvy (vitamin C) a physical disease and Beriberi (vitamin B1) a mental disease. Vitamins can be found in the cambium layer of trees, pine needles, and stinging nettle.
(c) Minerals. The mineral that we are primarily concerned with is Iron. Iron deficiency causes a 9% decrease in heat energy production. Iron acts as a thermo regulator. Consuming only 1/3 RDA of iron results in a 29% greater heat loss during cold exposure. Animal blood, dandelions, stinging nettle, and marrow provide the major source of iron. Ensure these foods are properly prepared.
(d) Calories. To produce energy, the body uses calories. Proteins, fats, or carbohydrates produce calories. Of these three, certain ones produce better energy than others do. Animal meat is an excellent source for caloric intake, although nuts from pinecones can supplement it.
1. Protein. Proteins are a reparative food of complicated molecules composed of chains of amino acids. There are numerous kinds of amino acids which cannot be synthesized by the body and thus must be consumed in the diet. A pure protein diet can cause fatalities in 3-8 weeks from Rabbit Starvation, a term used for living on a relatively fat free rabbit diet. Protein can be found in dandelions, nuts, and meats.
2. Fat. Fats serve as the main storage form of energy. Fats produce energy and heat. Fats are best obtained from bone marrow, liver, or the stomach portion of fish
3. Carbohydrates. Carbohydrates are known as the quick energy food. They produce lots of heat. They are stored in the liver and muscles. These organs are not large and can be markedly depleted by fasting for as short as 24 hours. Cattails, nuts are a source for carbohydrates.
C. PERSONAL HYGIENE
(1) Cleanliness is an important factor in preventing infection and disease. It becomes even more important in a survival situation.
(2) The areas to pay special attention to are the feet, hands, armpits, crotch, and hair. Visual and physical inspections should be conducted daily. Hand and finger nails should be kept as clean as possible to prevent infection of mucous membrane.
(a) Soap (lye) can be made from animal fat and ashes.
(b) Sun bath
(3) Teeth are another important area to keep clean. Brush your teeth each day either with a toothbrush, or if you don't have one, make a chewing stick.
(a) A chewing stick is made out of a twig about 6 to 8 inches long. Chew one end of the stick to separate the fibers. Now you can brush your teeth.
2 . FIVE WAYS THE BODY LOSES HEAT
A. Radiation: is direct heat loss from the body to its surroundings. If the surroundings are colder than the body, the net result is heat loss. A nude man loses about 60% of his total body heat by radiation. Specifically, heat is lost in the form of infrared radiation. Infrared targeting devices work by detecting radiant heat loss.
B. Conduction: is the direct transfer of heat from one object in contact with a colder object.
(1) Most commonly conduction occurs when an individual sits or rests directly upon a cold object, such as snow, the ground, or a rock. Without an insulating layer between the Marine and the object (such as an isopor mat), one quickly begins to lose heat. This is why it's important to not sit or sleep directly on cold ground or snow without a mat or a pack acting as insulation.
C. Convection: is heat loss to the atmosphere or a liquid. Air and water can both be thought of as “liquids” running over the surface of the body. Water or air, which is in contact with the body, attempts to absorb heat from the body until the body and air or water is both the same temperatures. However, if the air or water is continuously moving over the body, the temperatures can never equalize and the body keeps losing heat.
D. Evaporation. Heat loss from evaporation occurs when water (sweat) on the surface of the skin is turned into water vapor. This process requires energy in the form of heat and this heat comes from the body.
(1) This is the major method the body uses to cool itself down. This is why you sweat when you work hard or PT. One quart of sweat, which you can easily produce in an hour of hard PT, will take about 600 calories of heat away from the body when it evaporates.
E. Respiration. When you inhale, the air you breathe in is warmed by the body and saturated with water vapor. Then when you exhale, that heat is lost. That is why breath can be seen in cold air. Respiration is really a combination of convection (heat being transferred to moving air by the lungs) and evaporation, with both processes occurring inside the body.
3. PHYSICAL RESPONSES TO HEAT. When the body begins to create excess heat, it responds in several ways to rid itself of that heat.
A. Initially, the blood vessels in the skin expand, or dilate. This dilation allows more blood to the surface where the heat can more easily be transferred to the surroundings.
B. Soon afterwards, sweating begins. This contributes to heat loss through convection and evaporation.
4. PHYSICAL RESPONSES TO COLD. Almost the opposite occurs as with heat.
A. First, blood vessels at the skin surface close down, or constrict. This does two things:
(1) Less blood goes near the surface of the body so that less heat is lost to the outside.
(2) More blood goes to the “core” or the center of the body, to keep the brain, heart,lungs, liver, and kidneys warm. This means fingers and toes tend to get cold.
B. If that is not enough to keep the body warm, the next step is shivering. Shivering is reflexive regular muscular contractions, this muscular activity causes heat production. As mentioned before, shivering can only last for a short time before exhaustion occurs. With shivering you will either warm up, as usually occurs, or continue to get colder and start to become hypothermic. Hypothermia will be discussed later.
5. ENVIRONMENTAL INJURIES (Chap 14 b) Are cold weather injuries, dehydration, and altitude related illnesses.
A. COLD WEATHER INJURIES:
1) Hypothermia (Chap 14 c) is the state when the body’s core temperature falls to 95 degrees Fahrenheit or less. It is the number one killer of people in a survival situation. A common belief that extremely cold temperatures are needed for hypothermia to occur is not true. Most cases occur when the temperature is between 30 and 50 degrees Fahrenheit. This is the normal temperature range at MWTC, except during the harshest of winter.
a) Causes of Hypothermia. The ways in which the body generates and loses heat has been discussed earlier. Quite simply, hypothermia occurs when heat loss from the body exceeds the body's ability to produce heat.
Contributing factors include:
• Ambient temperature. Outside air temperature.
• Wind chill. This only affects improperly clothed individuals.
• Wet clothing.
• Cold water immersion.
• Improper clothing.
• Exhaustion.
• Alcohol intoxication, nicotine and drugs such as barbiturates and tranquilizers.
• Injuries. Those causing immobility or major bleeding, major burn and head trauma.
b ) Signs and symptoms of Hypothermia
• The number one sign to look for is altered mental status; that is, the brain is literally getting cold. These signs might include confusion, slurred speech, strange behavior, irritability, impaired judgment, hallucinations, or fatigue.
• As hypothermia worsens, victims will lose consciousness and eventually slip into a coma.
• Shivering. Remember that shivering is a major way the body tries to warm itself early on, as it first begins to get cold. Shivering stops for 2 reasons:
• The body has warmed back up to a normal temperature range.
• The body has continued to cool. Below 95?F shivering begins to decrease and by 90?F it ceases completely.
• Obviously, continued cooling is bad. So if a Marine with whom you are working, who was shivering, stops shivering, you must determine if that is because he has warmed up or continued to cool.
• A victim with severe hypothermia may actually appear to be quite dead, without breathing or a pulse. However, people who have been found this way have been successfully “brought back to life” with no permanent damage. So remember, you are not dead until you are warm and dead.
c) Prevention of Hypothermia
• Obviously, prevention is always better (and much easier) than treatment.
• Cold weather clothing must be properly warm and cared for.
• Keep your clothing as dry as possible.
• If your feet are cold, wear a hat. Up to 80% of the body's heat can escape from the head.
• Avoid dehydration. Drink 6 - 8 quarts per day.
• Eat adequately.
• Avoid fatigue and exhaustion.
• Increase levels of activity as the temperature drops. Do not remain stationary when the temperature is very low. If the tactical situation does not permit moving about, perform isometric exercises of successive muscles.
• Use the buddy system to check each other for signs/symptoms of hypothermia.
d) Treatment of Hypothermia.
• Make the diagnosis.
• Prevent further heat loss.
• Remove the victim from the environment (i.e., into a shelter or snow cave).
• Insulate the victim.
• Rewarm the victim by:
*Zip two sleeping bags together. *Pre-warm the bag by a stripped Marine. *Place the victim in the bag with 2 stripped Marines inside on both sides of the victim.
• Medevac if possible.
e) Other Points to Remember.
• Fluids. If the victim is mildly hypothermic, he may be given hot wets.
Otherwise give him nothing by mouth.
• Avoid, if possible, excessive movement of the victim, as his heart may stop beating if it is jarred.
• Major Wounds. Apply first aid to major wounds first, before attempting to re-warm the victim. Re-warming a victim who has bled to death does little good.
• Never give alcohol to hypothermia victims.
• Even after you have started re-warming a victim, he must be constantly monitored. Don't forget about him.
2) FROSTBITE Frostbite is the actual freezing of tissues. When in a survival situation, rewarming a severe frostbitten area will not help. It is best to wait for rescue and medical attention.
a) Prevention of Frostbite. Frostbite is an entirely preventable injury.
• Dress in layers. Keep comfortably cool. If you begin to become uncomfortable, add layers.
• Keep clothes dry. If clothing (especially socks and gloves) become wet, change them. This may mean you have to change sock 4-5 times a day.
• Dress properly. If the wind is blowing, wear the correct protective layer.
• Avoid dehydration. When dehydrated, the amount of blood available to warm your fingers and toes goes down, increasing the risk of frostbite.
• Avoid Starvation. Remember - Food is Fuel - and the body uses that fuel to make heat.
• Leadership must ensure that preventive measures are taken.
b) Signs and Symptoms of Frostbite.
• Ears, nose, fingers and toes are affected first.
• Areas will feel cold and may tingle leading to....
• Numbness which progresses to...
• Waxy appearance with skin stiff and unable to glide freely over a joint.
c) Treatment of Frostbite. Frostbite is classified into three different degrees: Frosting, Superficial Frostbite, and Deep Frostbite.
• Frosting will revert to normal after using the technique of body heat rewarming.
• Hold the affected area, skin to skin for 15 minutes.
*Rewarm face, nose, and ears with hands. *Rewarm hands in armpits, groin or belly. *Rewarm feet with mountain buddy’s armpits or belly.
• If affected area cannot be rewarmed in 15 minutes, Superficial Frostbite or Deep Frostbite is suspected.
Do not attempt to further rewarm Splint the affected area. Protect the affected area from further injury. Medevac as soon as possible. DO NOT RUB ANY COLD INJURY WITH SNOW. Do not massage the affected area. Do not rewarm with stove or fire: a burn injury may result. Loosen constricting clothing. Avoid tobacco products.
d) Treatment of Superficial or Deep frostbite. Any frostbite injury, regardless of severity, is treated the same – evacuate the casualty and re-warming in the rear. Unless the tactical situation prohibits evacuation or you are in a survival situation, no consideration should be given to re-warming frostbite in the field. The reason is something-called freeze – thaw – re-freeze injury.
• Freeze – Thaw – Re-freeze injury occurs when a frostbitten extremity is thawed out, then before it can heal (which takes weeks and maybe months) it freezes again. This has devastating effects and greatly worsens the initial injury.
• In an extreme emergency it is better to walk out on a frostbitten foot than to warm it up and then have it freeze again.
• Treat frozen extremities as fractures - carefully pad and splint.
• Treat frozen feet as litter cases.
• Prevent further freezing injury.
• Do not forget about hypothermia. Keep the victim warm and dry.
• Once in the rear, a frostbitten extremity is re-warmed in a water bath, with the temperature strictly maintained at 101?F - 108?F.
3 ) SNOW BLINDNESS
a. Definition. Sunburn of the cornea.
b. Causes of Snow Blindness. There are two reasons Marines in a winter mountainous environment are at increased risk for snow blindness.
• High altitude. Less ultraviolet (UTV) rays are filtered out, UV rays are what cause snow blindness (as well as sunburn). So at altitude, more UV rays are available to cause damage.
• Snow. The white color of snow reflects much more LTV rays off of the ground and back into your face.
c. Signs and Symptoms of Snow Blindness.
• Painful eyes.
• Hot, sticky, or gritty sensation in the eyes, like sand in the eyes.
• Blurred vision.
• Headache may be severe.
• Excessive tearing.
• Eye muscle spasm.
• Bloodshot eyes.
d. Prevention of Snow Blindness. Prevention is very simple. Always wear sunglasses, with UV protection. If sunglasses are not available, then field expedient sunglasses can be made from a strip of cardboard with horizontal slits, and charcoal can be applied under the eyes to cut down on reflection of the sun off the snow.
e. Treatment of Snow Blindness.
• Evacuation, when possible.
• Patch the eyes to prevent any more light reaching them.
• Wet compresses, if it is not too cold, may help relieve some of the discomfort.
• Healing normally takes two days for mild cases or up to a week for more severe cases.
4) TRENCHFOOT / IMMERSION FOOT
a) Definition. This is a cold - wet injury to the feet or hands from prolonged (generally 7 - 10 hours) exposure to water at temperatures above freezing.
b) Causes of Trench foot/Immersion Foot. The major risk factors are wet, cold and immobility.
c ) Signs and Symptoms of Trench foot/Immersion Foot.
• The major symptom will be pain. Trench foot is an extremely painful injury.
• Trench foot and frostbite are often very difficult to tell apart just from looking at it. Often they may both be present at the same time. Signs include:
• Red and purple mottled skin.
• Patches of white skin.
• Very wrinkled skin.
• Severe cases may leave gangrene and blisters.
• Swelling.
• Lowered or even absent pulse.
• Trench foot is classified from mild to severe.
d) Prevention of Trench foot/Immersion Foot is aimed simply at preventing cold, wet and immobile feet (or hands).
• Keep feet warm and dry.
• Change socks at least once a day. Let your feet dry briefly during the change, and wipe out the inside of the boot. Sock changes may be required more often.
• Exercise. Constant exercising of the feet whenever the body is otherwise immobile will help the blood flow.
e) Treatment of Trench foot/Immersion Foot.
• All cases of trench foot must be evacuated. It cannot be treated effectively in the field.
• While awaiting evacuation: - The feet should be dried, warmed, and elevated. - The pain is often severe, even though the injury may appear mild; it may require medication such as morphine.
• In the rear, the healing of trench foot usually takes at least two months, and may take almost a year. Severe cases may require amputation. Trench foot is not to be taken lightly.
B . DEHYDRATION
1. Dehydration is a deficit of total body water. Dehydration will compound the problems faced in a survival situation. Dehydration is the second leading cause of all deaths in a survival situation.
a) Symptoms. When dehydrated, the following signs and symptoms will appear:
• Headache and nausea.
• Dizziness and fainting.
• Cramps, both abdominal and extremity.
• Weakness and lethargy.
• Dark urine with a very strong odor.
• Always drink water when eating. Water is used and consumed as a part of the digestion process. If you have plenty of food but no water – Do not eat until a source of water can be found.
• Conserve energy. Pace yourself.
• Drink 6-8 quarts of water per day when available. In other words, continually drink through out the day. Don’t wait until you are dehydrated.
• Monitor the color of your urine.
• Don't rely on thirst as an indicator.
2. Heat related illnesses. The following illnesses will appear from dehydration:
1. Heat syncope. Heat syncope is feinting due to vaso-dilation from the heat.
2. Heat exhaustion. Heat exhaustion occurs when body salt losses and dehydration from sweating are so severe that a person can no longer maintain adequate blood pressure. Heat exhaustion can lead to heat stroke.
a) Symptoms include; headaches, nausea, dizziness, fatigue, and fainting.
3. Heat stroke. Heat stroke is a failure of the body's cooling mechanisms that rid the body of excessive heat build up.
a
) Signs and
symptoms
Symptoms are the same as heat exhaustion . The signs
include delirious or coma, pinpoint pupils, flushed skin, sweating
may or may not be present.
b) Heat cramps. Heat cramps are painful spasms of skeletal muscle as a result of body salt.
c) All of these illnesses can be detrimental to your survival. Dress properly, rest and adequate water intake can help prevent these illnesses.
C . ALTITUDE RELATED ILLNESSES:
1. Acute Mountain Sickness. Acute Mountain Sickness (AMS) is a self-limiting illness due to the rapid exposure of an unacclimatized individual to high altitude (i.e., helicopter crash on a mountain). Approximately 25% of individuals who ascend rapidly to 8,000 – 9,000 feet will develop AMS. Virtually, all unacclimatized persons who rapidly ascend to 11,00 – 12,000 feet will develop AMS.
(a) Signs and symptoms include; apathy, dizziness, easily fatigued, nausea, decreased appetite, headache. Can be misdiagnosed as dehydration. If adequate fluid intake is maintained and headache still persists rule out dehydration.
2. HACE. HACE or High Altitude Cerebral Edema is swelling of the brain
(a) Sign and symptoms are similar to AMS and accompanied by bizarre behavior, hallucinations, confusion, and severe cases – coma.
3. HAPE. High Altitude Pulmonary Edema is the filling of the lungs with fluid.
(a) Signs and symptoms include; persistent cough with pink frothy sputum, shortness of breath, disorientation, fainting, cool and clammy skin, blue lips
(1) Treatment Descend, Descend, and Descend. HACE and HAPE can result in death.
(2) Prevention Gain elevation slowly. 10,000 feet move 1000 feet per day over 14,000 move no faster than 500 – 1,000 feet per day. Rest and acclimatize your body.
D . CARBON MONOXIDE POISONING
1. Definition. Carbon Monoxide (CO) is a heavy, odorless, colorless, tasteless gas resulting from incomplete combustion of fossil fuels. CO kills through asphyxia even in the presence of adequate oxygen, because oxygen-transporting hemoglobin has a 210 times greater affinity for CO than for oxygen. What this means is that CO replaces and takes the place of the oxygen in the body causing Carbon Monoxide poisoning.
2. Signs/Symptoms. The signs and symptoms depend on the amount of CO the victim has inhaled. In mild cases, the victim may have only dizziness, headache, and confusion; severe cases can cause a deep coma. Sudden respiratory arrest may occur. The classic sign of CO poisoning is cherry-red lip color, but this is usually a very late and severe sign, actually the skin is normally found to be pale or blue.
CO poisoning should be suspected whenever a person in a poorly ventilated area suddenly collapses. Recognizing this condition may be difficult when all members of the party are affected.
3. Treatment. The first step is to immediately remove the victim from the contaminated area.
a) Victims with mild CO poisoning who have not lost consciousness need fresh air and light duty for a minimum of four hours. If oxygen is available administer it. More severely affected victims may require rescue breathing.
b) Fortunately, the lungs excrete CO within a few hours.
c) Prevention. Ensure there is adequate ventilation when utilizing a fire near your shelter.
6. MEDICAL AID. Unfortunately, during a survival situation, a corpsman may not always be available to render assistance. Therefore, the survivor must be knowledgeable in basic first aid as taught in the Marine Battle Skills Training Handbook.
A . Four Life Saving Steps
1) Start the breathing. 2) Stop the bleeding. 3) Treat the wound. 4) Check for shock.
B. Bites and stings Reptiles and insects of all kinds can complicate your survival situation. One of the best methods to reducing this risk is to wear your clothing properly.Do not scratch the bite or sting as this can cause the area to become infected.
1) Bee and Wasp stings. If stung by a bee, immediately remove the stinger and venom sac by scraping it with a fingernail or knife blade. Wash the sting site thoroughly.
a) Relief for itching and discomfort caused by bites and stings: Cold compress.
b) A cooling paste of mud and ashes.
c) Application of different plants.
2) Spider bites. Some people are extremely allergic to the venom associated with spiders. The spiders most venomous in this region are the black widow and the brown recluse. The black widow is black in color with a red hourglass on her belly which has a neurotoxin. The brown recluse has a fiddle on it's back which has a hemotoxin.
3) Scorpion stings. Scorpion stings may lead to respiratory distress. There are scorpions in the MWTC area. Scorpions throughout the world generally have neurotoxins.
4) Snakebites. There is always the possibility of snakebite throughout regions in the world. Learning the habitats of the indigenous snakes of the area you will be operating in will reduce the chance of being bitten.
a) Deaths from snakebites are rare, and the primary concern in treatment is to limit the amount of eventual tissue destruction around the bite area.
C. Wounds. Wounds are actual breaks in the integrity of the skin. Wounds can be caused by accident or by animals. These wounds are most serious in a survival situation, not only because of tissue damage and blood loss, but also because of infection. By taking proper care of the wound you can reduce the chance of a debilitating infection.
D. Animals. Prevention of an animal bite is best accomplished through knowledge of behavior, personalities, and patterns.
1) Animals generally give ample warning of their intentions, which are to repel the intruder or permit its escape. Animals that act out of character and approach humans should be considered rabid and avoided.
2) Tearing, cutting, and crushing injuries are combined in animal bites. Always look for secondary injuries.
E . First Aid. Whether the wound was caused by accident or by animal, the treatment remains the same.
1) Early cleansing of the wound reduces the chance of bacterial infection and is extremely effective in removing rabies and other viruses. Cleanse by irrigation. Bleeding wounds also helps the irrigation process initially.
2) Open wound management is best described by the “open treatment” method. Do not try to suture or close the wound. This will seal any dirt or infection into the wound. As long as the wound can drain it will usually not become life threatening.
a) Maggots b) Super glue c) Shunt
3) Tourniquet in a survival situation. If no rescue or medical aid is likely for over 2 hours, an attempt to SLOWLY loosen the tourniquet may be made 20 minutes after it is applied:
a) Ensure pressure dressing is in place.
b) Ensure bleeding has stopped.
c) Loosen tourniquet SLOWLY to restore circulation.
d) Leave loosened tourniquet in position in case bleeding resumes.
e) Bandaging is meant to protect the wound from foreign objects (i.e., dirt).
f) As with any injury to the body you must increase water intake, more so with an open wound.
F. Herbal Medicines
1) Consider using herbal medicines only after proper training and when you lack or have limited medical supplies.
2) WARNING Some herbal medicines are dangerous and may cause further damage or even death.
7. CASUALTY EVACUATION. Casualty evacuation in a cold weather mountainous environment will require a well thought out plan prior to conducting. Poorly planned evacuations will possibly result in additional casualties, lost time, and equipment damage. In a group survival situation expedient litter will have to be constructed in order to transport the patient effectively.
A. General Considerations. (Chap 14 d) The following considerations are critical for planning a successful evacuation. A useful acronym to use is “APASSNGG”.
1) Apply Essential First Aid. (i.e., splints, pressure bandage, etc.)
2) Protect the Patient form the Elements. Provide the casualty with proper insulation and ensure that he is warm and dry.
3) Avoid Unnecessary Handling of the Patient.
4) Select the Easiest Route. Send scouts ahead if possible, to break trails.
5) Set Up Relay Points and Warming Stations. If the route is long and arduous, set up relay points and warming stations to switch stretcher-bearers and assess the casualty.
6) Normal litter teams must be augmented in Arduous Terrain.
7) Give Litter Teams Specific Goals to work towards. This job is extremely tiring, both physically and mentally.
8) Gear. Ensure all of the patient’s gear is kept with him throughout the evacuation.
8. WILDLIFE DISEASES. (Chap 14 e) When handling animals, whether dead or alive, individuals must use preventive measures against possible exposure to wildlife diseases. Although the possibility of disease is remote, certain signs may indicate that an animal may be diseased. The following are some of the more common diseases found in the United States and throughout the world.
A. Hantavirus Pulmonary Syndrome. Hantavirus, or HPS, is a serious respiratory illness that was first recognized in 1993 in an outbreak in New Mexico and Arizona. It is caused by a virus that is carried by a common field rodent called the deer mouse.
1) Method of Transmission. The virus is shed in the droppings, urine, and saliva of the deer mouse. The virus is transmitted to humans when the material dries, becomes airborne and is inhaled.
2) Signs & Symptoms. The disease begins with flu-like symptoms 3 to 45 days after exposure. The disease can rapidly progress into a life-threatening lower respiratory illness characterized by the flooding of the lungs with fluid.
3) Treatment. No cure or vaccine is yet available against infection. The sooner after infection medical treatment is sought, the better the chance of recovery.
4) Prevention. Mice should not be handled; rodent dens should not be disturbed.Package food so that rodents do not crawl all over it. Do not occupy shelters that may have contained rodents.
B. Plague. The cause of plague is Yersinia pestis, a bacterium that is maintained in nature through a complex flea-rodent cycle.
1) Method of Transmission. Infection in humans results by flea bites, direct contact with plague-infected rodents, or direct contact with affected non-rodent hosts such as rabbits, hares, cats, and occasionally other animals.
2) Signs & Symptoms. Infection in humans results in severe disease, with a fatality rate of over 50% in untreated cases. An abnormal swelling in the lymph nodes is usually present.
3) Treatment. Infected people must seek medical treatment.
4) Prevention. Animal noted with fleas should be avoided. In a survival situation, a killed animal should be immediately submerged into a cool water source until all the fleas are remove by water or have died.
C. Tick Borne Diseases.
1) Lyme Disease. Infection occurs most often between May and September. In some cases, a characteristic skin rash may develop at the site of the tick bite. The rash may expand to a diameter of 5 inches or more, and there may be an accompanying flu-like illness. If left untreated, infection can lead to chronic disease characterized by neurologic impairment, cardiac problems, or arthritis.
2) Rocky Mountain Spotted Fever. The incubation period in humans is 2-14 days.Initial symptoms are flu-like and commonly include fever, headache, muscle and joint pain, nausea, and vomiting. A rash may appear. The fatality rate in cases that are treated with antibiotics is about 5% and up to 25% that are untreated.
3) Treatment. Infected people must seek medical treatment.
4) Prevention. Daily body inspections should be conducted to remove all ticks.
D. F ood Borne Diseases. Food borne illness, frequently called “food poisoning,” is acquired by eating food that is contaminated with microbes or their toxins. Live animals may carry the agent, or contamination may occur from another source during processing or preparation of the food.
1) Botulism. Botulism probably is the most widely known and is generally caused by improper storage of meats. Symptoms may begin with vomiting and diarrhea but proceed to the characteristic impaired vision and descending paralysis. Botulism can be fatal.
2) Salmonella. The bacteria are found in the intestinal tracts and feces of a wide range of animals including poultry, swine, cattle, and household pets. Salmonella maybe fatal.
3) Trichinosis. Trichinosis is caused by a parasite contained within the muscle tissue. Most common carriers are wild swine and bear. Thorough cooking of meats will destroy the parasite.
4) Tularemia. Discovered in Tulare County, California. Tularemia has been reported in over 45 species of vertebrates; however, the disease most often involves ticks. It is also commonly found in rabbits and rodents. It is transmittable by uncooked meats or handling contaminated meats with open sores. Tularemia is a life threatening disease found throughout the world and can only be treated with antibiotics.
5) Treatment. Consuming charcoal will aid in reducing the body’s absorption rate. Medical treatment should be sought if available.
6) Prevention. Prevention of food borne diseases can be accomplished by:
a) Promptly dress game.
b) Avoid or minimize contamination by gastrointestinal contents.
c) Cook food thoroughly. Internal cooking temperatures should be 165 degrees F or more.
d) Eat cooked foods immediately.
e) Store preserved foods properly.
E. Animal Scat. Certain parasites found on scat can infect humans, if the scat is handled unprotected. Raccoon Roundworm can be found in the scat for at least 30 days, while Fox Roundworm will last only approximately 7 days on their scat. Both of these parasites can possibly infect human, which is almost fatal.
REFERENCE:
1. FM 21-76, Survival, 1996.
2. Paul S. Auerbach, Wilderness Medicine, 3rd Edition, 1995.
3. William R. Davidson, Field Manual of Wildlife Diseases in the United States, 2nd Edition, 1997