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Role of the environment in the transmission of JC virus
Sílvia Bofill-Mas1, Rosina Girones
1Department of Microbiology, Faculty of Biology, University of Barcelona, Barcelona, Spain.
Abstract:
JC virus is etiologically associated with a fatal demyelinating disease known as PML. JCV produces persistent infections in the kidney and is excreted in the urine of healthy individuals and in the urine of PML patients. The characteristics of the JCV excreted in the environment have been studied by analyzing sewage samples from divergent geographical areas. The intergenic region of JCV strains detected in the sewage of Barcelona (Spain), Umeå (Sweden), Nancy (France), Pretoria (South Africa), Patras (Greece), Cairo (Egypt), Washington, D.C. (USA), and diverse areas of Northern India has been sequenced, and the phylogenetic analysis showed their relationships with JCV strains previously described in urine or clinical samples in these geographic areas. The JCV regulatory region of the JCV DNA detected in sewage presented archetypal or archetypal-like regulatory regions with the exception of one of the twenty clones obtained from a sewage sample of the area of Washington, D.C. that presented a tandem repeated structure. Infectivity studies showed that archetypal JCV present in the urine of a pregnant woman productively infected SVG cells. Also JC viral particles showed considerable stability in sewage at 20 degrees C and in front of treatments with acidic pH and trypsin. The high prevalence of JCV in urine and in sewage and the stability of the viral particles observed suggests that contaminated water, food, and fomites could be the vehicles of JCV transmission through the oral route. Virions partially degraded or noninfectious could be a source of JCV DNA and may represent an additional mechanism of entry of viral genes into cells.
Insights
John Cunningham virus (JCV) is found in sewage globally. Its stability and prevalence suggest transmission via contaminated water, food, or fomites through the oral route.
Area of Science:
- Environmental virology
- Molecular epidemiology
- Infectious disease transmission
Background:
- John Cunningham virus (JCV) causes progressive multifocal leukoencephalopathy (PML).
- JCV establishes persistent kidney infections and is excreted in urine by healthy individuals and PML patients.
- Understanding JCV environmental presence is crucial for public health.
Purpose of the Study:
- To characterize JCV strains in sewage from diverse global locations.
- To investigate the genetic diversity and phylogenetic relationships of environmental JCV.
- To assess the stability and infectivity of JCV in environmental conditions.
Main Methods:
- Sequencing of the JCV intergenic and regulatory regions from sewage samples.
- Phylogenetic analysis to compare environmental strains with known JCV isolates.
- Infectivity assays using SVG cells and stability tests under various environmental conditions (temperature, pH, trypsin).
Main Results:
- JCV strains with archetypal or archetypal-like regulatory regions were detected in most sewage samples worldwide.
- One unique strain with a tandem repeat structure was identified in Washington, D.C. sewage.
- Archetypal JCV from urine infected SVG cells, and viral particles demonstrated stability in sewage, acidic pH, and trypsin treatments.
Conclusions:
- The high prevalence and stability of JCV in sewage suggest transmission routes including contaminated water, food, and fomites via the oral route.
- Partially degraded or noninfectious virions may serve as a source of JCV DNA, potentially facilitating viral gene entry into cells.
- Environmental surveillance of JCV is important for understanding its epidemiology and transmission dynamics.
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