Impact of Universal Hepatitis B Vaccination on Prevalence, Infection-Associated Morbidity and Mortality, and Circulation of Immune Escape Variants in Russia.
METHODS
6,217 sera samples collected from volunteers in six epidemiologically different regions of Russia were tested for serological and molecular markers of HBV infection. A mathematical model developed by the U.S. Centers for Disease Control and Prevention was used to estimate the effect of vaccination and birth dose coverage on the incidence of HB and adverse outcomes of infection.


RESULTS
Prevalence of HBsAg in the study population varied from 1.2% to 8.2%; anti-HBc detection rates were 13.0-46.2%. HBsAg detection rates in epidemiologically significant cohorts were 0.6-10.5% in women of childbearing age; 0-2.4% in children ≤5 years old; 1.9-8.1% in adults ≥30 years old. Mathematical modeling demonstrated that the current 96.1-99.6% level of birth dose coverage increased the effectiveness of vaccination 10-21 times compared to 50% and 0% birth dose coverage scenarios. HBV DNA was detected in 63 sera samples. The frequency of amino acid substitutions in HBsAg was 38% (24/63). Only in 3% (2/63) the mutations were within the a-determinant of HBsAg (M133T and G145S, one case each). None of the identified mutations eluded HBsAg detection, since all these samples tested positive for HBsAg by commercial ELISA.


CONCLUSIONS
Despite a significant decline in acute HB incidence after the introduction of universal vaccination, many undiagnosed potential sources of infection remain. Low prevalence of HBV immune escape variants is a favorable predictor of vaccine effectiveness in the future.
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.|Department of Epidemiology and Evidence-Based Medicine of Prophylactic Medicine Faculty, I.M. Sechenov First Moscow State Medical University, The Ministry of Heath of the Russian Federation, Moscow, Russian Federation.
Vitalina V
VV
Klushkina
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Karen K
KK
Kyuregyan
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Tatiana V
TV
Kozhanova
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Oksana E
OE
Popova
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Polina G
PG
Dubrovina
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Olga V
OV
Isaeva
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Ilya V
IV
Gordeychuk
Department of Viral Hepatitis, Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, Russian Federation.
Mikhail I
MI
Mikhailov
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000401:mortality* / Q000628:therapy; D006510:Hepatitis B Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens / Q000378:metabolism; D017325:Hepatitis B Vaccines / Q000627:therapeutic use*; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D057131:Immune Evasion / Q000235:genetics / Q000276:immunology*; D007223:Infant; D008875:Middle Aged; D008962:Models, Theoretical; D009017:Morbidity; D015995:Prevalence; D012426:Russia / Q000453:epidemiology; D015996:Survival Rate; D014611:Vaccination; D055815:Young Adult
D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines