scorpion venom
What are the signs and symptoms of scorpion envenomation?
Venoms from scorpions produce a great variety of clinical symptoms in victims. The symptoms for any given incident vary according to several factors: species involved, toxicity of the venom, amount of venom injected, size of the victim, the victim’s overall health condition, and probably a number of other factors that vary from individual to individual that cannot be quantified. Envenomations are usually categorized into two or three levels of severity: 1) localized effects, 2) systemic effects, and 3) systemic effects with central nervous system involvement. Localized effects are common to nearly all scorpion stings regardless of the toxicity of the venom.
scorpion venom
These symptoms are restricted to the site of sting and include intense pain, minor swelling, redness or induration, numbness, tenderness, and tingling. Intense pain normally subsides within one hour, giving way to numbeness, tenderness, and tingling at the site of the sting. This normally results in the favoring of an affected limb. These symptoms normally fade after 24 hours. I compare the pain of most scorpion stings to hitting oneself on the thumb with a hammer. While excruciatingly painful, the sting does little or no visible tissue damage. Furthermore, the actual entry wound is not normally visible. The range of systemic involvement is very great.
The following signs and symptoms are often reported following scorpion envenomation: intense pain that radiates towards the body and is especially acute at the armpits and groin areas, aggitation or anxiety, increased body temperature, sweating, chills, a feeling of numbness or swelling of the face, tongue and throat, pain or tightness in the chest or back, and occasionally slightly increased heart rate and blood pressure.
scorpion venom
The victim is normally very anxious and some authors have attributed minor systemic symptoms to this anxiety. These systemic effects may occur very rapidly or may not manifest until several hours after the stinging incident. Systemic effects with CNS involvement are signs of severe envenomation. Such severe systemic involvement appears to be the result of massive release of catecholamines by the victim’s adrenal glands.
scorpion venom
Any of the following signs or symptoms is cause for concern: fever, excessive salivation, involuntary tearing, nausea or vomiting, confusion, coma, convulsions, increased or decreased heart rate or blood pressure, increased or involuntary defecation or urination, increased fluid excretion into the bronchioles and lungs, or swelling of the lungs. Death is usually due to heart or respiratory failure.
How many people are killed by scorpions?
Scorpion envenomation is a common hazard in many parts of the world. Unfortunately, we do not have a clear picture of how many people are stung world-wide each year, or even exactly how many are killed each year. The issue of scorpion envenomation continues to be surrounded by myth and sensationalism. Most scorpion stings probably occur in indigenous populations by scorpions that are of little or no medical importance. These people are accustomed to this threat and therefore treat scorpion stings the way most people would treat a bee or wasp sting. The vast majority of scorpion stings, perhaps hundreds of thousands every year on a world-wide basis, go unreported and require no medical treatment of any kind. In some countries, however, scorpion envenomation is a serious public health threat. The highly toxic nature of the venom of some scorpions gives people good reason to fear them.
Thousands, perhaps tens of thousands, of cases of scorpion envenomation are probably seen by medical professionals each year world-wide (unfortunately, there is no standard mechanism for reporting scorpion envenomation, so this is a only crude estimate). Of these cases, a few result in death for the victim. Table 3 presents the results of several retrospective studies conducted on scorpion envenomation around the world. Generally, these studies look only at cases that seek attention at medical treatment facilities. The number of stinging victims in the same area that do not seek medical attention is not known. Therefore, the mortality rates reported below are artificially high.
