The poison ivy does not normally occur in Slovakia, like in the Czech Republic, but it can be introduced. The venom of the black widow spider is an effective weapon for capturing prey. It is a mixture of various active substances containing a protein neurotoxin called α-latrotoxin (α-LTX). Necrotizing fasciitis (NF) is a rapidly progressive soft tissue infection caused by fulminant tissue destruction with severe systemic toxicity and high mortality (Fig. 9, Ref. 16). Keywords: poisonous weaver, necrotizing fasciitis, streptococcus pyogenes, latrodectism, multiorgan failure.