Medical Research Council - London Institute of Medical Sciences

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Trigger Bug
06 June 2017

Trigger Bug

Around half of all women will suffer from a urinary tract infection (UTI) at some point, and many are plagued by repeated attacks. UTIs are usually caused by E. coli gut bacteria straying into the bladder and are easily treated with antibiotics, but sometimes the bugs survive and lay low. They hide in a dormant form inside the cells lining the bladder until something causes the infection to reactivate, although until recently it wasn’t known what the trigger was. Researchers have now discovered that another type of bacteria usually found in the vagina – Gardnerella vaginalis – can sometimes get up into the bladder causing damage as they infect the lining cells (highlighted blue in this high-powered microscope image). This allows any dormant E. coli to break out and start growing again, causing the infection to flare up. Hopefully, understanding this bacterial battleground could end the pain and misery of recurrent UTIs.

Written by Kat Arney

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