Background: Polyomavirus BK and JC are the most common viral infection after renal transplantation. The current evidence shows that both virus infection has a greater risk on kidney graft function, leading the management of viral infection is becoming a major challenge.

Methods: We included 89 patients including 70 males and 19 females (follow up of 104 patients, mean follow-up 16.66 months) who were transplanted at 108 Military Central Hospital between December 2016 and December 2021. BK and JC polyomavirus screening was performed every 3 months within the first year after kidney transplantation, and every 6 months after year-1, or when any clinical infection symptoms were recognised by the physician. Multivariable Cox-regression analysis was performed to evaluate risk factors for the onset of BK, JC infection.

Results: 317 episodes of BK and JC infections were detected in 71 patients (52.8%) included Polyomavirus BK (26.0%), JC (21.8%), and BK and JC co-infection (5,0%). The mean time until onset of BK (15.39±20.06 months) was significantly earlier than JC (21.74±19.75 months), p<0.01. Risk factors for BK infection were hypertention (p<0.05, HR 1.79), and eGFR (p<0.05, HR 1.02). For sole JC infection, Systolic blood pressure (p<0.01, HR 1.06), Mycophenolate mofetil dose (p<0.001, HR 1.003). For the occurrence of co-infection, BMI (p<0.01, HR 1.25) and HDL-C (p<0.05, HR 1.25) were revealed as the most relevant factors. Male (p<0.05, HR 0.07) and eGFR (p<0.01, HR 0.94) were identified to reduce the risk of co-infection.

Conclusion: Our results showed hypertension and eGFR were independent risk factors for BK infection, while high Systolic blood pressure and high dose of mycophenolate mofetil for JC infection. BK and JC co-infection was associated with gender, BMI, HDL-C and eGFR. The result provided initial evidence for appropriate control and the prevention of Polyomavirus infection.