Snake Bite: Causes, Symptoms & Treatment

Snake bite is the term used to describe an injury, with possible poisoning consequences, caused by the bite of a snake.

What is a snake bite

In the case of a snake bite, the first thing that matters is whether the bite is from a venomous snake or a non-venomous snake. In addition, a distinction can be made between a venomous bite and a dry bite. A dry bite is a bite from a venomous snake in which no venom is released into the wound. On average, one out of every two bites from a venomous snake is a dry bite. Dry bites serve the snakes to deter the opponent without losing their venom, which is valuable for hunting.

Causes

Snakes are very shy and also nocturnal animals. Due to their very sensitive sensory organs, snakes register approaching humans very quickly and usually flee, so contact between humans and snakes is very rare. Estimates put the number of snakebites worldwide at around 2.5 million per year. Of these, about 400,000 are venomous bites. About 20,000 people die annually from poisoning by snakebites. Most snakebites occur in the summer months. This is partly because snakes are particularly active at this time and partly because many people spend their free time in nature at this time of year. Most poisonous snake bites happen in Australia, India, North and South America. However, a bite from the adder, which is native to Germany, can also lead to symptoms of poisoning.

Symptoms, complaints and signs

Symptoms of poisoning from a bite by a venomous snake differ depending on the type of venom. There are venoms that affect the nervous system, blood, tissues or muscles. The amount of venom injected and the patient’s state of health are also crucial to the expression of symptoms. Initial manifestations immediately after the snake bite are redness and pain at the bite site. Swelling and bleeding may also occur at the bite wound. Over the next few minutes to hours, severe tissue damage may develop. Neurotoxic snake venoms affect the nervous system. Symptoms such as dizziness, thirst, headache, or visual disturbances may indicate intoxication of the nervous system. If the injected venom is a hemotoxic venom, i.e., a venom that attacks blood cells, hemorrhages may occur throughout the body due to blood clotting disorders. Muscle paralyzing venoms cause shortness of breath, weakness or loss of coordination. Nausea, vomiting, or diarrhea may also occur with any venomous snake bite. Some snake species (for example, cobras) spit their venom. If this gets into the eyes, the affected person can go blind. Bites from non-poisonous snakes can also be life-threatening due to wound infections.

Diagnosis and course of the disease

The first action after a snake bite is to remove the injured person and all bystanders from the danger zone. If possible, an attempt should be made to identify the snake. Size, color, markings, head and eye shape, or perhaps even a photograph, can later help the physician choose the proper antiserum. Even if it is not clear whether the snake is a poisonous snake, a doctor must be consulted immediately or the emergency doctor must be called. Until the arrival of the doctor or during transport to the doctor, the patient should be moved as little as possible. The affected part of the body should be immobilized to prevent the venom from spreading more quickly. Local disinfection of the bite wound should be performed to prevent infection of the bite. Any further manipulation such as sucking out the venom, cutting out the wound, or applying a pressure dressing should be absolutely avoided. Instead, watches, rings, bracelets, or constricting clothing should be carefully discarded around the bite wound so that constriction will not occur even if swelling is severe.

Complications

Serious complications usually occur after a bite from a venomous snake. The venom of some snakes has a strong cell-damaging effect, destroying cells and tissues within a short time. Neurotoxins paralyze the central nervous system and result in death by respiratory paralysis without rapid injection of an antivenin.Myotoxins damage muscle tissue – during this process, the muscle protein myoglobin is released, which impairs kidney cell function and can cause kidney failure. Many snakebites trigger a blood clotting disorder that leads to unstoppable bleeding and, if untreated, fatal multi-organ failure. Cardiotoxic venoms disrupt electrolyte balance, impairing cardiac function. Many snake venoms are composed of several toxic substances and therefore cause several symptoms of poisoning at the same time. Allergic reactions, including anaphylactic shock, can occur both after a snakebite and after injection of the antivenom. The bite of a non-poisonous snake or a so-called dry bite without venom exposure can cause inflammation of the affected area as a complication. Occasionally the infection spreads to the nearby lymph nodes and lymphatic vessels, and in very rare cases this lymphangitis can result in blood poisoning (sepsis). Circulatory problems following a snakebite may be due to venom exposure, but may also occur as a sign of a panic reaction.

When should you see a doctor?

In the event of a snake bite, a doctor must always be consulted immediately. In the worst case, this can also lead to the death of the affected person if the bite is not treated in time or is treated late. In general, a very early diagnosis with an early treatment has a positive effect on the further course. A doctor should be consulted if the affected person has been bitten by a snake. As a rule, the bite is clearly noticeable and also leaves a bite wound. The affected person suffers from severe pain, swelling or even bleeding. If these complaints occur after the snake bite, a doctor must be consulted immediately. Likewise, a doctor must be consulted if the affected person suffers from shortness of breath or diarrhea and vomiting. These symptoms after a snake bite indicate a serious bite, which must be treated by a doctor. So, in case of a snake bite, the hospital should be visited immediately or an emergency doctor should be called.

Treatment and therapy

The bite site should be marked with a pen. Every 30 minutes, the progression of the swelling should be marked with another mark on the skin. This allows the progression of the envenomation to be documented. After a snake bite, victims are usually monitored as inpatients for 24 hours. Blood clotting and circulation are checked, and patients are examined for any symptoms of wound infection by, for example, tetanus bacteria. Antiserum is administered only if symptoms increase sharply or if there are acute severe symptoms of poisoning.

Prevention

Sturdy footwear should be worn when visiting snake areas. This should reach over the ankle if possible. The majority of snake bites occur near the ankle. Special gaiters are also available to protect against snakebites. Treading firmly when hiking will startle snakes by vibrating the ground. A walking stick placed in front of the feet at all times will also give the snake a heads up. Larger trees, bushes and shrubs should be avoided. Branches and stones lying on the ground should not be picked up or turned over under any circumstances. A sleeping snake may be hiding there. Supposedly dead snakes should not be touched under any circumstances. The same applies, of course, to live snakes. Under no circumstances should attempts be made to corner or capture snakes. If the snake threatens, immediately back away carefully and allow the animal to escape. In the dark, always use a flashlight to illuminate pathways and never sleep directly on the ground when spending the night outdoors. When camping, kitchen waste should be removed regularly. Garbage attracts mice, which in turn attract snakes.

Aftercare

Aftercare plays a role especially in diseases where there is a likelihood of recurrence. However, this may not be a medical responsibility in the case of a snake bite. Patients should exercise adequate caution in high-risk areas. Physicians can provide information on appropriate preventive measures, if necessary. For example, sturdy footwear and long pants will prevent a bite. L

Statistically, about half of all bites are completely symptom-free.The animals do not infect humans. Since there are no signs, follow-up is unnecessary. In other cases, follow-up is based on the symptoms. It may take several months until the final cure. During this time, blood tests are the most important analysis criterion. Vital functions are also checked regularly. Hospitalization for several days or weeks, followed by outpatient therapy, is not uncommon. In the worst case, a snake bite can also lead to amputations and tissue loss. In that case, follow-up is based on the existing symptoms. For example, therapy for phantom limb pain is indicated insofar as limbs had to be removed.

What you can do yourself

In the case of a blow bite should in no case imitate the measures often shown in movies and television. Sucking out or tying up the bite site often does more harm than good. The most important thing is to make sure that the victim remains calm. If the snake is a non-venomous species, then the wound can be treated like any other animal bite. That is, the wound should be cleaned and disinfected so that it does not become infected. Then, the wound can be protected from contamination with a band-aid or spray dressing. If it is a venomous snake, the victim should be taken immediately to the nearest hospital equipped to care for snake bite victims. Information about this can be obtained by calling the emergency number (in Germany 110). If the snake species is not known, the animal should be captured, if possible, or at least photographed or filmed so that the attending physician can determine which serum is needed. However, the first responders should not put themselves in danger during this process. The victim should be transported lying down and move as little as possible so that the poison is distributed as slowly as possible in the body. Tying off the bite site is only indicated if a highly venomous snake was involved and the nearest suitable hospital cannot be reached within about 30 minutes.