Irish scientists discover the cause of false widow spider ‘skin-eating’ conditions

Common house spiders can carry harmful bacteria that are susceptible to infecting people and can be transmitted through bites, new research by Irish scientists has found.

Research by NUI Galway scientists has also found that the Noble False Widow spider also carries harmful strains of bacteria that are resistant to common antibiotic treatments.

The study was published in the international journal Scientific Reports and explains a variety of symptoms experienced by victims bitten by the invasive spider Noble False Widow in Ireland and Great Britain over the past decade.

It shows that spiders carry harmful bacteria and that their germs can be transmitted when a spider uses its fangs to bite.

The rare “skin-eating” conditions after seemingly harmless European and North American spider bites were previously thought to be the result of secondary infections caused by scratching and probing the victim with contaminated fingers at the site of the bite.

Dr John Dunbar from the Ryan Institute Poison Systems Laboratory at NUI Galway explained that only about ten species of spiders common in northwestern Europe have fangs strong enough to pierce human skin and release venom.

However, he said that only one of these, the Noble False Widow spider, is considered of medical importance.

“Most of the time, a spider bite produces some redness and pain,” Dunbar said.

“In some cases, however, the victims seem to develop long-lasting infections that require strong antibiotic treatment and sometimes hospitalization.

“It is this ever-increasing range expansion and the massive increase in dense populations of false widow spiders around urbanized areas in Ireland and Great Britain that has seen an increase in bites with some serious symptoms of poisoning but also infections, which in some cases were even difficult to treat with antibiotics. “