Measles in Minsk, Belarus, 2001-2003: clinical, virological and serological parameters.
BACKGROUND
A number of cases of measles have been reported in the Republic of Belarus despite vaccine coverage of 98%. The absence of information on measles virus genotypes circulating in the Republic of Belarus has made it difficult to asses the situation.


OBJECTIVE
The purpose of this study was to isolate and sequence measles virus strains from clinical cases in Minsk, Belarus, and to estimate the role of vaccine failure in those cases.


METHODS
Between 2001 and 2003 years, 14 measles cases admitted to the Hospital of Infectious Diseases of Minsk were enrolled in our study. Clinical, routine laboratory, as well as serological and virological examinations were carried out. Detection of measles antibodies and IgG avidity testing was performed using commercial test kits. All measles cases were confirmed by RT-PCR and phylogenetically characterized.


RESULTS
Only 42.9% of the cases met the WHO laboratory criteria for measles, however, all cases were confirmed by RT-PCR. Most of the measles cases were attributed to secondary vaccine failure (SVF). Phylogenetic analysis revealed the presence of genotype A virus strains in 2001 and 2002 with D6 and D7 genotypes in 2003.


CONCLUSIONS
For the first time, MVs were genetically characterized in Belarus. Our results suggest that in a highly vaccinated population, most of measles cases represent vaccine failures and are vaccine-modified. Our results also indicate that confirmation of a clinical diagnosis of vaccine-modified measles requires a combination of serological and virological tests.
Atrasheuskaya
A V
AV
Laboratory of Immunology Safety, Institute of Molecular Biology, State Research Center of Virology and Biotechnology Vector, Koltsovo, Novosibirsk Region 630559, Russia. ignat@vector.nsc.ru
Blatun
E M
EM
Neverov
A A
AA
Kameneva
S N
SN
Maksimov
N L
NL
Karpov
I A
IA
Ignatyev
G M
GM
D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000032:analysis; D005838:Genotype; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007223:Infant; D008457:Measles / Q000453:epidemiology / Q000517:prevention & control / Q000821:virology*; D008458:Measles Vaccine / Q000627:therapeutic use; D008459:Measles virus / Q000235:genetics* / Q000276:immunology; D010802:Phylogeny; D002094:Republic of Belarus / Q000453:epidemiology; D014764:Viral Proteins / Q000235:genetics
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008458:Measles Vaccine; D014764:Viral Proteins