A large Finnish echovirus 30 outbreak was preceded by silent circulation of the same genotype

Abstract

An outbreak of echovirus 30 (E-30) in 2009 was confirmed by both frequent isolation of the virus from sewage as well as from patient samples in Finland. Over the last 10 years E-30 had only been isolated sporadically in Finland. We here study the phylogenetic relationships of the strains from the outbreak in the context of E-30 circulation over the last 20 years. The analyzed region comprised 276 nucleotides in the 5' end of VP1 (nucleotides 132-407 in the VP1 of the E-30 Bastianni strain). The Finnish strains were clustered into at least four distinct genogroups, with seven clusters exceeding the genotype demarcation of 12% and the 2009 epidemic strains forming the largest genogroup VII. Moreover, we detected largely divergent genotypes in 2007 and 2009. Interestingly, close genetic relatives of the epidemic strains had already been isolated a few years before the outbreak. Phylodynamic analysis estimated 8.9 years (95% highest posterior density intervals 7.0-11.0) as the age of genogroup VII, indicating a probable origin and evolutionary history prior to its introduction and epidemic expansion in Finland. Finally, the most recent common ancestor for the current E-30 diversity dates back to 1939 (95% highest posterior density intervals 1913-1956).

Sporadic Isolation of Sabin-Like Polioviruses and High-Level Detection of Non-Polio Enteroviruses during Sewage Surveillance in Seven Italian Cities, after Several Years of Inactivated Poliovirus Vaccination

“…These echoviruses are associated with childhood diseases, specifically, meningitis, respiratory, and gastrointestinal illnesses for Echo 11, febrile illness for Echo 4, and outbreaks of respiratory diseases for Echo 6 (79,80). Echovirus 30, which was the virus most commonly isolated during meningitis outbreaks in several countries (81,82,83,84,85), was detected with low frequency in the present study.…”

Intercity Spread of Echovirus 6 in Shandong Province, China: Application of Environmental Surveillance in Tracing Circulating Enteroviruses

“…However, gradually more studies have been published on the circulation and phylogenetic characterization of environmental NPEVs, such as the research work in the United States, Japan, Finland, Georgia, Greece, Iran, China, etc. (1,7,9,10,12,19,21,25,27). A high degree of genetic diversity and multiple genetic lineages of environmental NPEVs were also found by studies conducted in Georgia and Shandong (10,25,27), respectively, which probably resulted from the evolution of endemic viruses over a long period or from the importation of viruses from other regions.…”

“…It is a useful approach to trace prevalent and minor circulating enteroviruses in human populations (7). Moreover, several studies had revealed a close relationship among environmental and clinical isolates, reflecting the potential power of environmental surveillance to herald epidemics in the context of the low morbidity/infection ratio of HEV infection (19). In regions where there is no specialized HEV surveillance system, such as the situation in China, environmental surveillance is of more significance in understanding HEV circulation.…”

Enteroviruses Associated with Aseptic Meningitis in Poland, 2011–2014

“…The age distribution of meningitis cases varies, possibly due to different causative agents. Others studies described a large proportion of teenagers and young adults infected during previous E30 outbreaks (Khetsuriani et al, 2006;Savolainen-Kopra et al, 2011;Takamatsu et al, 2013).…”