The impact of antigenic drift of influenza A virus on human herd immunity: Sero-epidemiological study of H1N1 in healthy Thai population in 2009.
To examine the effect of the antigenic drift of H1N1 influenza viruses on herd immunity, neutralization antibodies from 744 sera from Thai healthy volunteers in 2008-2009, who had not been vaccinated for at least the last 5 years, were investigated by microneutralization (MN) and hemagglutination inhibition (HI) assays. Significantly higher MN titers were observed for the H1N1 Thai isolate in 2006 than in 2008. The results indicate that the antigenically drifted virus effectively escaped herd immunity. Since the low neutralization activity of herd immunity against drifted viruses is an important factor for viruses to spread efficiently, continuous sero-epidemiological study is required for public health.
Kanai
Yuta
Y
Section of Viral Infections, Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infections (RCC-ERI), Nonthaburi, Thailand. Yuta.Kanai@lshtm.ac.uk
Boonsathorn
Naphatsawan
N
Chittaganpitch
Malinee
M
Bai
Guirong
G
Li
Yonggang
Y
Kase
Tetsuo
T
Takahashi
Kazuo
K
Okuno
Yoshinobu
Y
Jampangern
Wipawee
W
Ikuta
Kazuyoshi
K
Sawanpanyalert
Pathom
P
D000956:Antigens, Viral / Q000235:genetics / Q000276:immunology*; D044466:Asian People; D005260:Female; D006801:Humans; D032521:Immunity, Herd; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology; D007251:Influenza, Human / Q000453:epidemiology / Q000276:immunology*; D008297:Male; D016036:Seroepidemiologic Studies; D013785:Thailand
D000956:Antigens, Viral; D007252:Influenza Vaccines