“Bug” meaning “insect” is a North Americanism [0]. The article is from The Guardian in the UK, where the non-insect meaning is the more natural interpretation, particularly in a headline (cf “hospital superbug” for stories about MRSA [1]).
[0] https://www.oxfordlearnersdictionaries.com/definition/englis... [1] https://www.nhs.uk/conditions/mrsa/