Prevalence of Nonpolio Enteroviruses in the Sewage of Guangzhou City,China, from 2009 to 2012

The human-pathogenic viruses in urban sewage have been extensively monitored to obtain information on circulating viruses in human communities. Enteroviruses (EVs) excreted by patients who present with diverse clinical syndromes can remain infectious in the environment for several weeks, and limited data on circulating environmental EVs are available. A 4-year (2009 to 2012) surveillance study was conducted to detect nonpolio enteroviruses (NPEVs) in the urban sewage of Guangzhou city, China. After the viruses in the sewage samples were concentrated and isolated, molecular identification was used to detect and type the NPEVs. During the 4-year study, 17 different NPEV serotypes were identified in the sewage of Guangzhou city. The most common serotypes were echovirus 11 (ECHO11), ECHO6, ECHO7, and ECHO12 and coxsackie group B viruses 5 (CVB5) and CVB3. The predominant serotypes were influenced by spatial and temporal factors and differed each year. CVB5 was commonly detected in 2009 and 2010 but was rarely isolated in 2011 and 2012. In contrast, CVB3 was not observed in 2009 and 2010 but was increasingly detected in 2011 and 2012. Our study provides an overview of the serotype distribution and circulation patterns of NPEVs in the sewage of Guangzhou, China. In the absence of a systematic EV disease surveillance system, the detection and characterization of sewage-borne NPEVs will help us better understand the changes in EV disease trends and the epidemic background of circulating EVs, which could help interpret the EV trends and warn of future outbreaks in this area.