Severe influenza outbreak in Western Ukraine in 2009--a molecular-epidemiological study.
BACKGROUND
In the autumn of 2009 the authors participated in a humanitarian operation in Western Ukraine by undertaking an epidemiological investigation of an influenza-like-illness (ILI) in the L'viv Oblast region. Mobile biological survey teams took samples from civilian patients with severe acute respiratory distress syndrome, rapid transportation of the samples, and their molecular analysis in Poland to provide accurate results.


OBJECTIVE
The aim of the study was the molecular and epidemiological analysis of the biological samples collected.


METHODS
Real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR), multiplex PCR techniques, traditional Sanger Sequencing and classical viral culture methods were used.


RESULTS
Among the 124 influenza-like illness cases, ~50% (58) were positive for influenza A virus in WHO-CDC molecular assay, including subtyping. The specimens were further analyzed to confirm results and determine the genetic sequence. Phylogenetically, the nucleotide similarity of both the Ukraine specimens and reference A/California/7/2009 (pH1N1) was 99.2-99.3%. Oseltamivir resistance was not registered. HA1 region characterization showed an overall protein identity of 98.5-99.4%.


CONCLUSIONS
An unexpected high contribution of influenza A was confirmed among ILI patients, as well as a very limited number of other detected viruses, indicate that the 2009 epidemic in western Ukraine was strongly related to novel influenza A/H1N1. The importance of swift sharing of information and reference laboratories networking in surveillance, as well as serving governments and international agencies in pursuing adequate actions, should be stressed.
Military Institute of Hygiene and Epidemiology, Department of Epidemiology, Warsaw, Poland.
Janusz
J
Kocik
Marcin
M
Niemcewicz
Matthew
M
Johns
Kurt
K
Jerke
Aleksander
A
Michalski
Anna
A
Bielecka
Krzysztof
K
Lasocki
Jerzy
J
Gaweł
Agata
A
Bielawska-Drózd
Justyna
J
Joniec
Marcin
M
Kołodziej
Grzegorz
G
Graniak
Mariusz
M
Goniewicz
Leszek
L
Kubiak
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology; D008297:Male; D008875:Middle Aged; D058873:Pandemics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D014455:Ukraine / Q000453:epidemiology; D014776:Virus Cultivation; D055815:Young Adult