Redback Spider

© 2020 CTC Productions Pty Limited. All rights reserved. The material presented on this website, may not be reproduced or distributed, in whole or in part, without the prior written permission of CTC Productions.

Redback Spider

In 1995 a colony of Redback Spiders was found around the port area in Osaka, Japan. Despite attempts to eradicate the spider it seems to be thriving, and there are fears that it will spread throughout Asia. Japanese authorities don’t really know how the spider reached their country. Osaka is a major sea and air port and it’s thought that Australian wool exports are a prime suspect, as the spiders’ pale eggs could easily be missed in bales of wool. Tests show that the venom of the Osaka spiders is similar to that of Australian Redbacks, and so Japanese bite victims can be treated effectively with antivenom produced in Australia by the Commonwealth Serum Laboratories.

Redback Spiders (Latrodectus hasselti)

Closely related to the black widow spider group found world-wide, Redbacks are black in colour, with a distinctive red/orange stripe on the abdomen. The spiders are very common throughout Australia, especially in urban areas. They like to hide in dry sheltered sites, for example under the bottom rails of fences, under shelves, in sheds, underneath outdoor furniture or in piles of rubbish. The males are very small and are considered harmless. Bites from the females, which are about 2-3cm (1") long, can cause sweating, nausea, vomiting and severe pain. Redbacks are not aggressive.

Bites

Bites are very common, and most people are bitten on the limbs. However a survey showed that years ago in the days of backyard dunnys, 80% of the victims were men using the toilet. Most bites are minor, with less than 20%, or less than 1 in 5 of the victims requiring antivenom. Even so, hundreds of people require antivenom for Redback Spider bites every year in Australia. In fact sometimes the venom can cause pain for months after the victim is bitten if treatment is not given. If bitten by a Redback Spider apply ice packs to the wound to relieve the pain and seek medical aid. Do not apply a pressure-immobilisation bandage.