Previous Article | Next Article 
Journal of Clinical Microbiology, February 2008, p. 665-670, Vol. 46, No. 2
0095-1137/08/$08.00+0 doi:10.1128/JCM.02386-06
Copyright © 2008, American Society for Microbiology. All Rights Reserved.
Analysis of Echovirus 30 Isolates from Russia and New Independent States Revealing Frequent Recombination and Reemergence of Ancient Lineages
Alexander N. Lukashev,1,2*
Olga E. Ivanova,1
Tatiana P. Eremeeva,1 and
Larisa V. Gmyl1
Institute of Poliomyelitis and Viral Encephalitides RAMS, Moscow, Russia,1
Bute Medical School, University of St Andrews, Scotland, United Kingdom2
Received 27 November 2006/
Returned for modification 31 October 2007/
Accepted 27 November 2007

ABSTRACT
We studied two genome regions, VP1 and 3D, of 48 echovirus 30
(E30) isolates from Russia and the new independent states. In
VP1, most isolates were similar to European strains reported
earlier, and frequent change of circulating subgroups was noticed.
We also observed, in 2003-2006, the reemergence of a group of
E30 strains with a VP1 region very distant from most modern
E30 strains and remotely similar to E30 isolates from the 1960s
and the 1970s. A study of the 3D genome region detected multiple
recombination events among the studied strains. Recombination
presumably occurred every few years, and therefore, the study
of a single VP1 genome region cannot accurately describe the
phylogenetic history of the virus or predict pathogenetic properties
of an isolate. In general, a comparison of the VP1 and 3D genome
region phylogenies revealed, in some instances, virtually independent
circulation of enterovirus genome fragments on a scale of years.

INTRODUCTION
Echovirus 30 (E30) is a member of the human enterovirus B (HEV-B)
species, which also includes 28 serotypes of echoviruses, 6
coxsackie B viruses, coxsackie A9 virus and several new enterovirus
serotypes. Enteroviruses cause a wide spectrum of clinical manifestations.
Most frequently, the infection is asymptomatic or subclinical;
however, severe and life-threatening forms are not rare (
18).
E30 has recently been a common cause of meningitis in many countries
(
4,
5,
7,
9,
12,
14,
19) and was a subject of several epidemiological
studies (
2,
15,
21); therefore, many sequences for the VP1 genome
region are available in GenBank for comparison. Previously,
however, most studies of E30 epidemiology were conducted by
using only the VP1 genome region. A number of recent publications
revealed that intertypic recombination is a very frequent event
in circulating enteroviruses, thus allowing virtually independent
evolution of different genome regions (
8,
10,
16). In this work,
we studied the epidemiology of E30 in Russia and the new independent
states (NIS) in 1998-2006 by using two genome regions, VP1 and
3D, to estimate the role of recombination in the short-term
epidemiology of enteroviruses.

MATERIALS AND METHODS
We used 48 strains of E30 isolated in the course of the WHO
polio surveillance program and enterovirus surveillance (Table
1). Virus isolation and identification were carried out according
to a standard WHO protocol (
24) by using RD and Hep-2 cell cultures.
Strain serotypes were identified by neutralization test with
antisera produced by RIVM (Bilthoven, The Netherlands). Virus
RNA was isolated from cell culture supernatant by guanidine
thiocyanate lysis and adsorption to silica (
3). Reverse transcription
was carried out using Moloney murine leukemia virus reverse
transcriptase (Promega) and random hexanucleotide primers. PCR
was performed with previously published oligonucleotides for
VP1 (
15) and 3D (
11). All nucleotide positions are given according
to the prototype E30 strain Bastianni (GenBank accession no.
AF311938). After amplification, bands were excised from agarose
gels, purified using QIAquick kits (Qiagen), and sequenced directly
with the PCR primers. Nucleotide sequences were aligned using
ClustalX software (
23). Phylogenetic trees were constructed
with ClustalX (neighbor-joining algorithm), with correction
for multiple substitutions and excluding positions with gaps,
and with 1,000 bootstrap pseudoreplicates. RNA and protein sequence
distances were calculated with the PHYLIP software package (
6).
GenBank accession numbers for sequences are provided in Table
1.

RESULTS AND DISCUSSION
In the VP1 genome region (nucleotides [nt] 2460 to 3335), all
E30 strains differed by up to 31% of nucleotide sequence (DNADIST,
Kimura model) and by up to 20.5% of protein sequence (PROTDIST,
Jones-Taylor-Thornton distance matrix). All strains grouped
with the prototype E30 Bastianni relative to enteroviruses of
other serotypes, thus confirming the serotype. We used 75 of
over 150 GenBank sequences available for E30 VP1 that were reported
previously (
1,
15,
21), excluding very similar (less than 2%
nucleotide sequence difference) strains from the same geographic
region. The nucleotide sequence of the prototype E21 Farina,
the closest HEV-B serotype to E30, was used to root the phylogenetic
tree, but was omitted from Fig.
1. Most of the strains studied
fell into a major phylogenetic group that included most E30
strains isolated worldwide since 1978 and sequenced so far.
This group was reported previously in several studies (
15,
21);
therefore, the majority of the strains from Russia and the NIS
studied here were similar to other recent E30 isolates reported
elsewhere. One explanation for the observed global group of
modern strains that differ from each other far less (below 13%
nucleotide sequence, PHYLIP Dnadist, Kimura model) than do the
E30 isolates from the 1960s and the 1970s (up to 32% of nucleotide
sequence) is probably the higher fitness of this genotype, as
was hypothesized previously (
21). As shown by Fig.
1, most of
the modern strains had the same putative ancestor relative to
the strains from the 1960s and 1970s. We also suggest that an
increase in economical ties and the spread of air travel have
resulted in the emergence of a common epidemiological space
in Europe and North America, where a more fit capsid could efficiently
prevail in a matter of several years.
Within the "modern" group, phylogenetic subgrouping did not
always correlate with isolation location, but rather correlated
with the time of isolation, which indicates a very dynamic epidemiological
pattern. In general, we observed limited temporal overlap between
subgroups that circulated in Russia and the NIS. Sublineages
of E30 demonstrate quick and wide spreading within months over
vast distances and then vanish to give space to newer lineages.
It seems unlikely to us that the epidemiology of E30 is significantly
driven by herd immunity pressure, as the sequence difference
between most subgroups implies only minor serological differences.
Some strains in the major modern group, such as those in subgroups 1, 2, and 3 (Fig. 1), presumably arrived from Western Europe not very long before isolation in Russia. These strains originated mainly from Russia and the western NIS; however, strains of subgroup 2 could be found in Middle Asia (in Kirghizia). This observation is not unexpected and shows that the epidemiological space of the former USSR is significantly integrated into the European epidemiological space. Strains that comprise subgroup 4 seemingly diverged from the main E30 lineage over two decades ago, as they are almost an out-group within the major modern group. Viruses of subgroup 4, especially strain 23199, were similar to recent Chinese isolates and probably represent an Asian sublineage. It should be noted that we observed nonuniform rates of E30 isolation within Russia and the NIS. Most strains studied here came from Russia and Caucasia and Western countries, and only several E30 strains were among many HEV-B isolates from Middle Asia.
Rather unexpectedly, we observed a group of six strains (subgroup 5) (Fig. 1) that was strikingly different from most other modern E30 strains. These isolates were only somewhat similar to a Columbian strain isolated in 1995 and probably originated from countries where enterovirus surveillance was not performed. A close look at subgroup 5 does not allow inferring the spreading pattern of these strains. Older Georgian strains make a subset within subgroup 5; therefore, multiple introductions of different sublineages of this group likely took place (see below). Reemergence of subgroup 5 strains that fell outside the modern E30 major group demonstrates that surveillance carried out in developed countries for E30, arguably the best-studied nonpolio enterovirus, does not explicitly reflect world epidemiology of E30. We speculate that strains of this group originated from less-developed regions with less dynamic and less "global" epidemiologies, where they could have been maintained for decades. This observation not only is important for an understanding of E30 or HEV-B epidemiology but also implies that "eradicated" polio may reemerge decades later from secluded reservoirs.
Partial sequences for 3D genome fragments (nt 6468 to 6931 of E30 Bastianni) of the strains studied were aligned with available sequences of HEV-B strains of different serotypes, as E30 could be expected to recombine extensively with other HEV-B strains in the nonstructural protein (NSP) region (8, 10). Enterovirus B strains differed by up to 31.5% of nucleotide sequence and by up to 9.7% of protein sequence; thus, a majority of substitutions in this genome region were synonymous. A phylogenetic tree was created with poliovirus 1 sequence added to provide a correct root (Fig. 2). E30 strains studied here followed a grouping pattern reported previously for most modern HEV-B strains that cluster either with prototype E30 or with E1/E9, yet again supporting an observation of ubiquitous recombination in enteroviruses (10, 17, 20). In this work, however, we were mostly interested in a short-term incidence of recombination among strains isolated within only 7 years. A comparison of phylogenetic grouping in VP1 and 3D genome regions indicates many occasions of recombination over this short time frame. Only two phylogenetic groups observed in VP1, subgroups 1 and 2, were fully maintained in the 3D genome region. Within subgroup 3, strain 22696, indistinguishable from the group in VP1 and isolated close in time and location with strain 23184, was clearly recombinant in 3D. Viruses of subgroups 4 and 5, which were very similar and grouped very reliably in VP1, bore multiple marks of recombination in 3D. Strains of subgroup 4 possessed five different 3D polymerase regions (Fig. 2). These strains were hardly distinguishable in the VP1 region, which is traditionally used for typing, yet very diverse in the 3D region and, presumably, in most of the nonstructural genome region. Interestingly, strain 23199 had a 3D region very distant from those of most modern strains, again showing that rare enterovirus genome parts can persist and then reemerge in a virus that would not seem unusual from the conventional VP1 region analysis. Strains of subgroup 5 have also undergone multiple recombination events and fell into three distinct groups in the 3D genome region. Again, as was observed for subgroup 3, strains isolated at the same location in Georgia, within a 10-month interval and very similar in VP1, bore notably different nonstructural genome regions. We can thus conclude that subgroup 5 in VP1 indicates the emergence not of a new virus lineage, but of a new capsid lineage.
Phylogenetic trees for structural and nonstructural genome regions
indicate that different genome regions in enteroviruses circulate
independently even on a scale of a few years. While it would
not be correct to estimate the exact frequency of recombination
in circulating E30 from our data, it is perfectly obvious that
it is about once every few years, much as was recently shown
for HEV-B (
22). Indeed, 16 of 47 strains studied probably recombined
within the last five years before being isolated and all E30
strains of the major modern group in the VP1 genome region were
recombinant in 3D compared not only to the prototype strains
of the 1950s but also to the HEV-B isolated in the 1980s and
1990s. Considering our results, especially those for subgroups
4 and 5, it would be incorrect to say that one can trace the
circulation of individual strains; rather, one can trace the
circulation of discrete capsid or nonstructural genome regions
that only temporarily coexist as a distinct virus. Importantly,
in the NSP region, E30 can recombine with any HEV-B strain;
therefore, study of a single serotype would always produce a
rather limited result that would not clearly reflect the epidemiology
of NSP genome regions of a species. Flexible and highly dynamic
genetics and epidemiology of circulating E30 and presumably
of other enteroviruses oblige us to expect the emergence and
rapid spread of strains with unusual properties. Our results
also indicate that as long as enterovirus surveillance is carried
out using only the VP1 genome region, either molecularly or
in a neutralization test, we have a significantly reduced chance
of linking the clinical manifestations and epidemiology of enterovirus
infection.

ADDENDUM
After the manuscript was submitted, a study of E30 epidemiology
in France also reported frequent recombination between VP1 and
3D regions (
13).

ACKNOWLEDGMENTS
The E30 strains were isolated as a part of the WHO Polio Eradication
Program in the European Region.
This study was supported by grants for surveillance for poliomyelitis and AFP from the WHO and Ministry of Health of the Russian Federation. We are particularly grateful to Bute Medical School, University of St. Andrews, for the possibility to complete this study.
We express our acknowledgments to E. Nasirova (Republican Centre for Epidemiology and Hygiene, Baku, Azerbaijan), T. Kutateladze (National Centre for Disease Control, Tbilisi, Georgia), K. Kasymbekova (Centre for Immunoprophylaxis, Bishkek, Kyrgyzstan), V. Gidirim (National Centre of Preventive Medicine, Kishinev, Moldova), L. Yektova (Centre for State Sanitary Epidemiological Surveillance, Donetsk, Ukraine), I. Demchishina (Ukrainian Centre for State Sanitary Epidemiological Surveillance, Kiev, Ukraine), L. Kotlik (Central Laboratory of AIDS of Odessa, Ukraine), G. Osipchuk (Republican Sanitary-Epidemiological Station, Tashkent, Uzbekistan), T. Amvros'eva (Institute of Epidemiology and Microbiology, Minsk, Byelorussia), O. Utnitskaya (State Center of Sanitary-Epidemiological Surveillance, Yekaterinburg, Russia), M. Bichourina (Pasteur Institute, St. Petersburg, Russia), S. Kuribko (State Center of Sanitary-Epidemiological Surveillance, Moscow, Russia) and E. Romanenko (State Center of Sanitary-Epidemiological Surveillance, Stavropol, Russia) for providing the strains. We are grateful to Richard Iggo (University of St Andrews, United Kingdom) for critical reading of the manuscript.

FOOTNOTES
* Corresponding author. Mailing address: Bute Medical School, University of St Andrews, St Andrews, Fife, Scotland, KY16 9TS, United Kingdom. Phone: 44-01334-467191. Fax: 44-01334-462595. E-mail:
Alexander_lukashev{at}hotmail.com 
Published ahead of print on 12 December 2007. 

REFERENCES
1 - Bailly, J.-L., A. Beguet, M. Chambon, C. Henquell, and H. Peigue-Lafeuille. 2000. Nosocomial transmission of echovirus 30: molecular evidence by phylogenetic analysis of the VP1 encoding sequence. J. Virol. 38:2889-2892.
2 - Bailly, J. L., D. Brosson, C. Archimbaud, M. Chambon, C. Henquell, and H. Peigue-Lafeuille. 2002. Genetic diversity of echovirus 30 during a meningitis outbreak, demonstrated by direct molecular typing from cerebrospinal fluid. J. Med. Virol. 68:558-567.[CrossRef][Medline]
3 - Boom, R., C. Sol, M. Salimans, C. Jansen, P. Wertheim-van Dillen, and J. van der Noordaa. 1990. Rapid and simple method for purification of nucleic acids. J. Clin. Microbiol. 28:495-503.[Abstract/Free Full Text]
4 - Dos Santos, G. P., I. Skraba, D. Oliveira, A. A. Lima, M. M. de Melo, C. I. Kmetzsch, E. V. da Costa, and E. E. da Silva. 2006. Enterovirus meningitis in Brazil, 1998-2003. J. Med. Virol. 78:98-104.[CrossRef][Medline]
5 - Faustini, A., V. Fano, M. Muscillo, S. Zaniratti, G. La Rosa, L. Tribuzi, and C. A. Perucci. 2006. An outbreak of aseptic meningitis due to echovirus 30 associated with attending school and swimming in pools. Int. J. Infect. Dis. 10:291-297.[CrossRef][Medline]
6 - Felsenstein, J. 1989. PHYLIP: phylogeny inference package (version 3.2). Cladistics 5:164-166.
7 - Helfand, R. F., A. S. Khan, M. A. Pallansch, J. P. Alexander, H. B. Meyers, R. A. DeSantis, L. B. Schonberger, and L. J. Andersson. 1994. Echovirus 30 infection and aseptic meningitis in in parents of children attending a child care center. J. Infect. Dis. 169:1133-1137.[Medline]
8 - Lindberg, M. A., P. Andersson, C. Savolainen, M. N. Mulders, and T. Hovi. 2003. Evolution of the genome of human enterovirus B: incongruence between phylogenies of the VP1 and 3CD regions indicates frequent recombination within the species. J. Gen. Virol. 84:1223-1235.[Abstract/Free Full Text]
9 - Lopez Alcala, M. I., M. Rodriguez Priego, D. de la Cruz Morgado, and J. M. Barcia Ruiz. 1997. Outbreak of meningitis caused by echovirus type 30. An. Esp. Pediatr. 46:237-240. (In Spanish.)[Medline]
10 - Lukashev, A. N., V. A. Lashkevich, O. E. Ivanova, G. A. Koroleva, A. E. Hinkkanen, and J. Ilonen. 2003. Recombination in circulating enteroviruses. J. Virol. 77:10423-10431.[Abstract/Free Full Text]
11 - Lukashev, A. N., V. A. Lashkevich, G. A. Koroleva, J. Ilonen, G. G. Karganova, V. I. Reznik, and A. E. Hinkkanen. 2003. Molecular epidemiology of enteroviruses causing uveitis and multisystem hemorrhagic disease of infants. Virology 307:45-53.[CrossRef][Medline]
12 - Maisonneuve, L., V. Esteve, G. Scart, D. Lusina, M. P. Le Pennec, F. Baledent, and E. Bingen. 1999. PCR SSCP study of an echovirus 30 meningitis outbreak. Pathol. Biol. 47:534-538.[Medline]
13 - Mirand, A., C. Henquell, C. Archimbaud, H. Peigue-Lafeuille, and J. L. Bailly. 2006. Emergence of recent echovirus 30 lineages is marked by serial genetic recombination events. J. Gen. Virol. 88:166-176.[CrossRef]
14 - Mori, I., K. Matsumoto, M. Hatano, M. Sudo, and Y. Kimura. 1995. An unseasonable winter outbreak of echovirus type 30 meningitis. J. Infect. Dis. 31:219-223.
15 - Oberste, M. S., K. Maher, M. L. Kennett, J. J. Campbell, M. S. Carpenter, D. Schnurr, and M. A. Pallansch. 1999. Molecular epidemiology and genetic diversity of echovirus type 30 (E30): genotypes correlate with temporal dynamics of E30 isolation. J. Clin. Microbiol. 37:3928-3933.[Abstract/Free Full Text]
16 - Oberste, M. S., K. Maher, and M. A. Pallansch. 2004. Evidence for frequent recombination within species human enterovirus B based on complete genomic sequences of all thirty-seven serotypes. J. Virol. 78:855-867.[Abstract/Free Full Text]
17 - Oberste, M. S., S. Penaranda, and M. A. Pallansch. 2004. RNA recombination plays a major role in genomic change during circulation of coxsackie B viruses. J. Virol. 78:2948-2955.[Abstract/Free Full Text]
18 - Pallansch, M. A., and R. P. Roos. 2001. Enteroviruses: polioviruses, coxsackieviruses, echoviruses, and newer enteroviruses, p. 723-775. In D. M. Knipe and P. M. Howley (ed.), Fields virology, 4th ed., vol. 1. Lippincott-Raven, Philadelphia, PA.
19 - Reintjes, R., M. Pohle, U. Vieth, C. Lyytikainen, H. Timm, E. Schreier, and L. Petersen. 1999. Community wide outbreak of enteroviral illness caused by echovirus 30: a cross-sectional survey and a case-control study. Ped. Infect. Dis. J. 18:104-108.[CrossRef]
20 - Santti, J., T. Hyypia, L. Kinnunen, and M. Salminen. 1999. Evidence of recombination among enteroviruses. J. Virol. 73:8741-8749.[Abstract/Free Full Text]
21 - Savolainen, C., T. Hovi, and M. N. Mulders. 2001. Molecular epidemiology of echovirus 30 in Europe: succession of dominant sublineages within a single major genotype. Arch. Virol. 146:521-537.[CrossRef][Medline]
22 - Simmonds, P., and J. Welch. 2006. Frequency and dynamics of recombination within different species of human enteroviruses. J. Virol. 80:483-493.[Abstract/Free Full Text]
23 - Thompson, J., T. Gibson, F. Plewniak, F. Jeanmougin, and D. Higgins. 1997. The ClustalX windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Res. 24:4876-4882.
24 - WHO. 1992. WHO manual for the virological investigation of polio. WHO, Geneva, Switzerland.
Journal of Clinical Microbiology, February 2008, p. 665-670, Vol. 46, No. 2
0095-1137/08/$08.00+0 doi:10.1128/JCM.02386-06
Copyright © 2008, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Leitch, E. C. M., Bendig, J., Cabrerizo, M., Cardosa, J., Hyypia, T., Ivanova, O. E., Kelly, A., Kroes, A. C. M., Lukashev, A., MacAdam, A., McMinn, P., Roivainen, M., Trallero, G., Evans, D. J., Simmonds, P.
(2009). Transmission Networks and Population Turnover of Echovirus 30. J. Virol.
83: 2109-2118
[Abstract]
[Full Text]