 About 75% of the world's nasties are arthropods I.e. Insects such as bees, wasps, ants, spiders, scorpions or tarantulas.
While most of them are harmless to humans, a few are well capable of inflicting a nasty bite or sting that can cause significant medical problems. Bees, wasps, hornets, 'fire ants' and bullet ants all have the necessary firepower.
Some people are very sensitive or even allergic to bites, in which case they have an anaphylactic shock reaction, and some even die. The answer in such cases is to carry adrenaline, hydrocortisone, and antihistamine injections to self-administer in the event of a bite, a precaution which can be life saving. I have come across death caused by the stings from swarms of bees, 'killer bees' and wasps but fortunately these are rare cases, and tend to affect very sensitive people.
I have never been stung by a bee or wasp, but have been bitten by 'fire ants' on a jungle trek. The pain is an excruciating 'burning' sensation, but it's not as bad as that brought on by an encounter with bullet ants, which feels as if you've been shot- fortunately, I cannot confirm the comparison.
This feature, however, is mainly concerned with the more sinister arthropods, that the adventurous Adventure Travel reader may encounter. So, here we go.
Spiders
There are 34,000 species of spiders recorded (although the actual number on earth is undoubtedly much, much higher) and an estimated 170,000 sub species. Only a handful are considered to be greater, and like snakes, we probably do the majority of them a gross injustice.
Most spiders have venom glands, but not all are venomous to man. Spider venom, like snakebite venom, is generally neurotoxic (affecting heart/nervous system) or cytotoxic, (causing more serious local tissue damage) when highly venomous.
The neurotoxic spiders include the window family, including the infamous Black Widow spider, which is black, shiny, has a fat body, and distinctive red or orange markings on its underside – and can be deadly. Others are known by 'other' names such as the Show Button spider (S. Africa), Katipo (New Zealand), Red Black (Australia), Malmignatte and Karakurt (Europe). So, the reality is, you're not safe anywhere!
These species are nocturnal, and build a seemingly haphazard tangle of silk for their web. They tend to live in rock outcrops, under logs and stones, and have adapted to human environments, such as out buildings, garden clutter and toilets. Which I why the most common bites occur on the buttocks and genitalia. Widow spider bites kill about 5% of their victims.
Another little critter is the banana spider, which had bright red hairs, and lives in Central and South America and is prevalent in the foliage of banana trees.
The Australian funnel-web spiders are large, dangerous and aggressive, and live on the east coast of Australia, including Sydney. Before antivenom became available, death occurred in minutes for infants, two hours for small children and within a day for adults.
Cytotoxic spiders include the Violin, Fiffleback, Recluse, Hobo spider (US Pacific Northwest), and the Yellow Sac spiders (can be yellow, green, pink or tan, depending on what they have eaten). These spiders are found worldwide, but most common in the tropics and jungles.
The brown recluse spider has a distinct violin mark on its head. This group are medium sized, with uniformly coloured abdomens that vary from a tawny to dark brown. The legs are covered with fine hairs. They also have six eyes arranged in pairs, are nocturnal, make a protective silk retreat, and can be found in cracks and crevices of houses, as well as in their more expected habitats. In S. America they are known as the 'spider that lives behind the picture'. Bites often occur at night, when the unsuspecting victim is sleeping, and rolls over onto one of them.
Tarantulas
Contrary to widespread belief these large spiders are virtually harmless despite their imposing size and large fangs. Most of their bites are innocuous by venomous standards.
Scorpions
Scorpions can be found throughout the tropical and sub tropical belts in habitats ranging from dry deserts to mountains, usually in South, West and North Africa, North, Central and South America, India ad the Caribbean.
Not all scorpions are dangerous, and only a small number of species are a threat to man. The most dangerous are found in the Middle East, Asia and Africa. The unpleasant one in N. America hang out in Arizona, New Mexico and the Californian side of the Colorado River. In Mexico each year there are 1 to 2000 deaths from scorpion bites so it may not be the best place for your honeymoon.
Scorpions are also nocturnal and often hide in dark cracks and vegetation. They also like cupboards, duvets, under the bed, and resting up in shoes. Because of their size they can travel reasonably quickly and stowaways are often found in cargo, and large ports.
Scorpions sting with a poisoned hook on their tail, which is typically raised prior to an attack. The scorpion bite is extremely painful, and this is a good indicator of what may have bitten you. It tends to cause neurogenic symptoms.
Symptoms and signs from bites/stings
Simple non-venomous bites or sting produce an area of redness and swelling, with local discomfort and/or itchiness, but with little systemic upset. Treatment includes analgesics, possibly an antihistamine, and a steroid cream locally, to reduce the inflammation. If a more severe allergic reaction in a susceptible individual occurs, urgent medical treatment is required.
More Serious Symptoms and Signs from bites/stings
There can be resultant from the more venomous spider and scorpion bites. General symptoms include a stinging, smarting pain at the site of the pain, which can be severe. Anxiety, sweating, headache, nausea, vomiting, salivation, watering of the eyes and a raised or lowering of temperature may occur.
The neurogenic type bites can cause more serious systemic upset as well as the above with muscle pains and cramps, tightness in the chest, difficulty in walking, swallowing, breathing, talking, convulsions, palpitations, cardio-respiratory arrest and death.
The cytotoxic bites/sting can cause the general symptoms plus severe destruction of local tissue where the bite/sting occurs. Swelling and pain develop, followed by blistering and necrosis (tissue death). Sloughing then takes place leaving a significant ulcerated wound that may take months to heal, and possibly need a skin graft. Secondary infections are common, requiring antibiotics. Deeper tissue wounds, including musculature, are less common but can and do occur, and take it from me that's not nice.
Those at greater risk from the more severe bites/stings include the young, especially below six years of age, and those older than 60. People with cardiovascular disease and susceptible to an allergic reaction are at a greater risk. Other factors include general health, the amount of venom injected, and the site of the bite. The risk in such cases is bigger when the bite or sting is near to the head, neck or torso, as the venom will gain quicker access to the heart and nervous system.
First aid and treatment for spider/scorpion bites
* If someone is bitten, try and keep the culprit for identification which will assist treatment. It goes without saying that no heroics are advisable if capture necessities further danger to others.
* Keep the patient as motionless as possible. This may not be practical when out in the wild, and getting them to help and further assistance may be the better option, especially if their condition is worsening.
* Eating, drinking and smoking should be avoided in the short term
* Call for medical assistance if possible
* Keep the patient on his/her back, or side with feet raised above the body
* Loosen tight clothing
* Apply artificial respiration and heart compression if they stop breathing
* Apply crushed ice (if available) to the affected area, as the cold helps to retard the action of the venom, and reduce pain. Do no leave the ice on for too long as more tissue damage may eventually ensue.
* Analgesia/pain relief may be necessary and eventually antibiotics and anti-tetanus injection should be given if warranted.
* Any antiseptic if available will also be useful
Do Not
* Use alcoholic drinks as this can mask symptoms or exacerbate them
* Use potassium permanganate on the wound
* Cut the wound
* Use a tourniquet, as this could aggravate the local effects of the venom, and cause even more tissue damage, especially in the cytotoxic type of bite.
* Use anti-snake bite venom
There are antiserums for spider venom, but their administration needs to be overseen by a doctor.
Prevention
As always prevention is better than cure. These nasties are generally nocturnal and don't just exist out in the bush. Be vigilant especially at night. Check your bedding, shoes and any back packs, any open nooks or crannies and when you visit the loo. When out in the bush don't go exploring under logs, rocks or in crevices.
However, as is the case with snakes there are a far greater number of innocuous spiders than painful ones – the psychological hang-ups about spiders and creepy crawlies is probably far more debilitating. And for that, you'll need a psychiatrist; 'do you want to tell me all about it?'
Have fun.
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