Particulate matter exposure increases JC polyomavirus replication in the human host

Background: Human polyomaviruses (HPyVs) asymptomatically infect the human population during childhood and establish latency in the host. Viral reactivation and urinary excretion can occur when the immune system is impaired. Exposure to particulate air pollution, including the PM₁₀/PM_2.5 components, is a public health problem and has been linked to several disorders. Studies assessing the relationship between PM₁₀/PM_2.5 exposure and viral replication are lacking. Objectives: To investigate the relationship between HPyVs viruria and PM₁₀/PM_2.5 exposures. Methods: Individual environmental exposure was assessed in 50 healthy adult volunteers using a chemical transport model (CTM) with a municipality resolution for daily PM₁₀ and monitoring stations data for daily PM_2.5 exposures. For each subject, a urine sample was collected, and HPyVs (JCPyV, BKPyV, MCPyV, HPyV6, HPyV7 and HPyV9) loads were determined. Zero-inflated negative binomial (ZINB) regression was used to model the count data, as it contained excessive zeros. Covariates were chosen by stepwise selection. Results: HPyVs DNA was detected in 54% (median:87.6*10⁵ copies/ml) of the urine samples. JCPyV was the prevalent (48%, (median viral load:126*10⁵ copies/ml). Considering the load of the most frequently measured HPyVs, JCPyV, in the count-part of the ZINB model, every unitary in PM measured 2 days before urine collection (PM Day −2) was associated with an increase in JCPyV load (PM₁₀: +4.0%, p-value = 0.002; PM_2.5: +3.6%, p-value = 0.005). In the zero-part, the significant predictor was the PM₁₀ measured 5 days before urine collection (+3%, p-value = 0.03). Conclusions: The environmental levels of PM₁₀/PM_2.5 increase the JCPyV viruria. Our findings emphasize the need for studies assessing the influence of air pollution exposure on the risk of viral reactivation. The environmental levels of PM₁₀/PM_2.5 increase the Human JC Polyomavirus viruria, showing an increasing risk of viral replication linked to the air pollution exposure.