Agri Kultuur December / Desember 2018 - Page 56

Spider bites in southern Africa Jonathan Leeming, T he subject of spider bite is a rabbit warren of hoax emails, misinformation, misconceptions and ignorance. It’s almost impossible to identify a lesion or wound as being caused by a spider bite, and at the same time, it’s is equally impossible to say that a spider was not involved. Common sense says that unless you watch the spider bite you, you must raise the question of if a spider was the cause at all. Misdiagnosis of spider bite all over the world has reached pandemic proportions. In many instances, people claim to have been bitten by spiders, despite a distinct lack of any evidence. The usual reaction is that “It can only be a spider” or “What else can it be?” This perception has resulted in mass hysteria, numerous hoax emails and widespread misinformation. It’s very strange that people who work with spiders daily almost never get bitten by them! The following should be noted: The average spider is completely harmless. • Out of over 2500 named species of spider in South Africa only about 18 are deemed medically important. • Arachnophobia is one of the top 10 mental disorders in the world. • Seeing a spider in your house, does not mean you have been bitten by a spider. • Although there are some excellent medical professionals practicing, many general practitioners still understand very little about spiders and the effects of their venom. • Violin Spider bites are not common throughout South Africa. AgriKultuur |AgriCulture • The average Internet website is a terrible source of information on spider bites. • Most spider bite images on the Internet are not actually spider bites or even spider related. • Bacterial and viral infections are often the cause of bite-like lesions. Asking for spider bite advice on Facebook and Internet groups generally results in the regurgitation of misinformation, hearsay and hoaxes. The 2 common causes of misidentified spider bite are MRSA infections and diabetic ulcers. The Plant Protection Research Institute in Pretoria houses the National Collection of Arachnida, which includes a database of over 50 000 spider records dating back to before 1973. These records are sourced from scientific research and surveys, with a large proportion submitted by the general public from densely populated areas. It’s interesting to note that of more than 50 000 records, only 131 pertain to Violin Spiders. This data demonstrates the scarcity of Violin Spiders in the urban environment. Research has shown that medical professionals who practice in areas where spider bites regularly occur, are better at recognising the symptoms. In areas where spider bites are rare, misdiagnosis is more frequent. For example, Violin Spider bites are often diagnosed where these spiders are not known to occur. It is possible, but very rare, that spiders are brought into an area through human activities. 56