Final answer:
Women are the most susceptible to recurring UTIs due to their shorter urethra and proximity to the anus, risk factors such as sexual activity, and other health conditions that facilitate bacterial growth and infection resistance.
Step-by-step explanation:
The group most susceptible to recurring urinary tract infections (UTIs) is women, particularly due to their anatomical features. The female urethra is shorter and closer to the anus than in males, which makes it easier for GI tract bacteria like Escherichia coli to cause infections. Women's susceptibility is further increased by factors such as sexual activity, especially when certain contraceptives like spermicides or diaphragms are used, as well as conditions like diabetes, obesity, and changes in the immune system. Other risk factors that contribute to the recurrence of UTIs include poor hygiene, the use of urinary catheters, and specific conditions in men like an enlarged prostate or kidney stones. In severe cases, recurrent infections might be due to bacteria forming biofilms, which are more resistant to antibiotics, or due to infections with antimicrobial-resistant strains such as Klebsiella pneumoniae.