hemagglutination inhibition tests


Summary: Serologic tests in which a known quantity of antigen is added to the serum prior to the addition of a red cell suspension. Reaction result is expressed as the smallest amount of antigen which causes complete inhibition of hemagglutination.

Top Publications

  1. Shinde P, Koratkar S, Pawar S, Kale S, Rawankar A, Mishra A. Serologic evidence of avian influenza H9N2 and paramyxovirus type 1 infection in emus (Dromaius novaehollandiae) in India. Avian Dis. 2012;56:257-60 pubmed
    ..Performance of both HI and MN assays was similar, suggesting the utility of using the MN assay along with HI assay for surveillance studies. This is the first report of the seroprevalence of AI H9N2 and APMV-1 in emus in India...
  2. Tan G, Krammer F, Eggink D, Kongchanagul A, Moran T, Palese P. A pan-H1 anti-hemagglutinin monoclonal antibody with potent broad-spectrum efficacy in vivo. J Virol. 2012;86:6179-88 pubmed publisher
    ..The broad but specific activity of MAb 6F12 highlights the potent efficacy of monoclonal antibodies directed against a single subtype of influenza A virus. ..
  3. Ferguson M, Risi G, Davis M, Sheldon E, Baron M, Li P, et al. Safety and long-term humoral immune response in adults after vaccination with an H1N1 2009 pandemic influenza vaccine with or without AS03 adjuvant. J Infect Dis. 2012;205:733-44 pubmed publisher
    ..75-?g HA AS03(A)-adjuvanted H1N1 2009 influenza vaccine was highly immunogenic in both age strata (18-64 and >64 years), inducing long-term persistence of the immune response until at least 6 months after dose 1. ..
  4. Vesikari T, Block S, Guerra F, Lattanzi M, Holmes S, Izu A, et al. Immunogenicity, safety and reactogenicity of a mammalian cell-culture-derived influenza vaccine in healthy children and adolescents three to seventeen years of age. Pediatr Infect Dis J. 2012;31:494-500 pubmed publisher
    ..CCIV produced in mammalian cell culture is a safe, well-tolerated and immunogenic alternative to conventional egg-derived influenza vaccines for children and adolescents. ..
  5. Frasca D, Diaz A, Romero M, Phillips M, Mendez N, Landin A, et al. Unique biomarkers for B-cell function predict the serum response to pandemic H1N1 influenza vaccine. Int Immunol. 2012;24:175-82 pubmed publisher
  6. Andrews N, Walker W, Finn A, Heath P, Collinson A, Pollard A, et al. Predictors of immune response and reactogenicity to AS03B-adjuvanted split virion and non-adjuvanted whole virion H1N1 (2009) pandemic influenza vaccines. Vaccine. 2011;29:7913-9 pubmed publisher
    ..Reduction in the interval between doses for earlier protection would be at the cost of reduced immunogenicity. The effect of seasonal vaccine on immunogenicity merits further investigation. ..
  7. Koita O, Sangare L, Poudiougou B, Aboubacar B, Samake Y, Coulibaly T, et al. A seroepidemiological study of pandemic A/H1N1(2009) influenza in a rural population of Mali. Clin Microbiol Infect. 2012;18:976-81 pubmed publisher
  8. He W, Han H, Wang W, Gao B. Anti-influenza virus effect of aqueous extracts from dandelion. Virol J. 2011;8:538 pubmed publisher
    ..Mechanisms of reduction of viral growth in MDCK or A549 cells by dandelion involve inhibition on virus replication. ..
  9. Black S, Nicolay U, Vesikari T, Knuf M, Del Giudice G, Della Cioppa G, et al. Hemagglutination inhibition antibody titers as a correlate of protection for inactivated influenza vaccines in children. Pediatr Infect Dis J. 2011;30:1081-5 pubmed publisher
    ..Although a cutoff of 1:110 may be used to predict the conventional 50% clinical protection rate, a titer of 1:330 would predict an 80% protective level, which would seem to be more desirable from a public health perspective. ..

More Information


  1. Moreno A, Lelli D, Brocchi E, Sozzi E, Vinco L, Grilli G, et al. Monoclonal antibody-based ELISA for detection of antibodies against H5 avian influenza viruses. J Virol Methods. 2013;187:424-30 pubmed publisher
  2. Pomorska Mól M, Markowska Daniel I, Kwit K. Immune and acute phase response in pigs experimentally infected with H1N2 swine influenza virus. FEMS Immunol Med Microbiol. 2012;66:334-42 pubmed publisher
    ..g. vaccine efficiency investigations) or as a marker for disease severity, but to confirm this hypothesis more studies are needed...
  3. Ohmit S, Petrie J, Cross R, Johnson E, Monto A. Influenza hemagglutination-inhibition antibody titer as a correlate of vaccine-induced protection. J Infect Dis. 2011;204:1879-85 pubmed publisher
    ..Vaccine failures from clinical trials need to be examined to determine why seemingly protective HAI titers may not protect. Clinical Trials Registration. NCT00538512. ..
  4. Esposito S, Marchisio P, Montinaro V, Bianchini S, Weverling G, Pariani E, et al. The immunogenicity and safety of a single 0.5 mL dose of virosomal subunit influenza vaccine administered to unprimed children aged ?6 to <36 months: data from a randomized, Phase III study. Vaccine. 2012;30:7005-12 pubmed publisher
    ..Our results show that a single 0.5 mL dose effectively and safely provided long-term immunogenicity to all three influenza strains in unprimed children aged at least 6 to <36 months. ..
  5. Hu Z, Hu S, Meng C, Wang X, Zhu J, Liu X. Generation of a genotype VII Newcastle disease virus vaccine candidate with high yield in embryonated chicken eggs. Avian Dis. 2011;55:391-7 pubmed
    ..Taken together, these results suggest that NDV/AI4 can provide better protection than LaSota and is a promising vaccine candidate against genotype VII NDV...
  6. Gilca V, De Serres G, Hamelin M, Boivin G, Ouakki M, Boulianne N, et al. Antibody persistence and response to 2010-2011 trivalent influenza vaccine one year after a single dose of 2009 AS03-adjuvanted pandemic H1N1 vaccine in children. Vaccine. 2011;30:35-41 pubmed publisher
    ..In contrast, two doses of the 2010-2011 TIV were necessary to induce an adequate immune response to the A/Perth/16/2009(H3N2) and B/Brisbane/60/2008 strains in children previously naïve to seasonal vaccine. ..
  7. Zoth S, Gómez E, Carballeda J, Carrillo E, Berinstein A. Expression of a secreted version of the hemagglutinin-neuraminidase glycoprotein of Newcastle disease virus: its evaluation as a diagnostic reagent. J Vet Diagn Invest. 2011;23:519-23 pubmed publisher
    ..The present results show that the cloning strategy developed yielded the HN protein free in the cell culture supernatant and that the recombinant protein retained its reactivity with anti-NDV HN antibodies in chicken sera...
  8. Szymczakiewicz Multanowska A, Lattanzi M, Izu A, Casula D, Sparacio M, Kovács C, et al. Safety assessment and immunogenicity of a cell-culture-derived influenza vaccine in adults and elderly subjects over three successive influenza seasons. Hum Vaccin Immunother. 2012;8:645-52 pubmed publisher
    ..Safety and immunogenicity of CCIV was not influenced by the type of vaccine received previously or by concomitant PV administration. ..
  9. Patel S, Atmar R, El Sahly H, Guo K, Hill H, Keitel W. Direct comparison of an inactivated subvirion influenza A virus subtype H5N1 vaccine administered by the intradermal and intramuscular routes. J Infect Dis. 2012;206:1069-77 pubmed publisher
    ..Evaluation of higher dosages, alternative intradermal delivery methods, and the addition of adjuvants will be needed to enhance the immunogenicity of inactivated influenza A/H5N1 vaccines by the intradermal route. NCT00439335. ..
  10. Block S, Yi T, Sheldon E, Dubovsky F, Falloon J. A randomized, double-blind noninferiority study of quadrivalent live attenuated influenza vaccine in adults. Vaccine. 2011;29:9391-7 pubmed publisher
    ..97-1.25), and 0.92 (95% CI, 0.82-1.03), respectively. Solicited symptoms and adverse events were similar in the Q/LAIV and T/LAIV arms. Q/LAIV may confer increased protection against influenza by targeting B strains from both lineages. ..
  11. Skowronski D, Hottes T, De Serres G, Ward B, Janjua N, Sabaiduc S, et al. Influenza Β/Victoria antigen induces strong recall of Β/Yamagata but lower Β/Victoria response in children primed with two doses of Β/Yamagata. Pediatr Infect Dis J. 2011;30:833-9 pubmed publisher
    ..Repeated annual TIV doses containing B/Victoria-lineage antigen strongly recalled antibodies to the B/Yamagata antigen of first exposure, but elicited lower B/Victoria responses. ..
  12. Domachowske J, Pankow Culot H, Bautista M, Feng Y, Claeys C, Peeters M, et al. A randomized trial of candidate inactivated quadrivalent influenza vaccine versus trivalent influenza vaccines in children aged 3-17 years. J Infect Dis. 2013;207:1878-87 pubmed publisher
    ..QIV may offer improved protection against influenza B in children compared with current trivalent vaccines. ..
  13. Khurana S, Frasca D, Blomberg B, Golding H. AID activity in B cells strongly correlates with polyclonal antibody affinity maturation in-vivo following pandemic 2009-H1N1 vaccination in humans. PLoS Pathog. 2012;8:e1002920 pubmed publisher
    ..The ability to generate high affinity antibodies could have significant impact on the elucidation of age-specific antibody responses following vaccination and eventual clinical efficacy and disease outcome. ..
  14. Walker W, de Whalley P, Andrews N, Oeser C, Casey M, Michaelis L, et al. H1N1 antibody persistence 1 year after immunization with an adjuvanted or whole-virion pandemic vaccine and immunogenicity and reactogenicity of subsequent seasonal influenza vaccine: a multicenter follow-on study. Clin Infect Dis. 2012;54:661-9 pubmed publisher
  15. Tsatsaris V, Capitant C, Schmitz T, Chazallon C, Bulifon S, Riethmuller D, et al. Maternal immune response and neonatal seroprotection from a single dose of a monovalent nonadjuvanted 2009 influenza A(H1N1) vaccine: a single-group trial. Ann Intern Med. 2011;155:733-41 pubmed publisher
    ..French National Institute of Health and Medical Research. ..
  16. Qiu C, Tian D, Wan Y, Zhang W, Qiu C, Zhu Z, et al. Early adaptive humoral immune responses and virus clearance in humans recently infected with pandemic 2009 H1N1 influenza virus. PLoS ONE. 2011;6:e22603 pubmed publisher
    ..These findings provide new important insights on the human immunity to natural influenza infection. ..
  17. Block S, Falloon J, Hirschfield J, Krilov L, Dubovsky F, Yi T, et al. Immunogenicity and safety of a quadrivalent live attenuated influenza vaccine in children. Pediatr Infect Dis J. 2012;31:745-51 pubmed publisher
    ..The immunogenicity of Q/LAIV was noninferior to that of T/LAIV in children aged 2-17 years; safety was also comparable. Q/LAIV may broaden the protection against influenza B strains provided by current trivalent influenza vaccines. ..
  18. Hardelid P, Andrews N, Hoschler K, Stanford E, Baguelin M, Waight P, et al. Assessment of baseline age-specific antibody prevalence and incidence of infection to novel influenza A/H1N1 2009. Health Technol Assess. 2010;14:115-92 pubmed publisher
    ..The National Institute for Health Research Health Technology Assessment programme and the Health Protection Agency. ..
  19. Barrett P, Berezuk G, Fritsch S, Aichinger G, Hart M, El Amin W, et al. Efficacy, safety, and immunogenicity of a Vero-cell-culture-derived trivalent influenza vaccine: a multicentre, double-blind, randomised, placebo-controlled trial. Lancet. 2011;377:751-9 pubmed publisher
    ..Federal (US Government) funds from the Office for Preparedness and Response, Biomedical Advanced Research and Development Authority, under contract to DynPort Vaccine Company. ..
  20. Meyer S, Adam M, Schweiger B, Ilchmann C, Eulenburg C, Sattinger E, et al. Antibody response after a single dose of an AS03-adjuvanted split-virion influenza A (H1N1) vaccine in heart transplant recipients. Transplantation. 2011;91:1031-5 pubmed publisher
  21. Roman F, Clement F, Dewé W, Walravens K, Maes C, Willekens J, et al. Effect on cellular and humoral immune responses of the AS03 adjuvant system in an A/H1N1/2009 influenza virus vaccine administered to adults during two randomized controlled trials. Clin Vaccine Immunol. 2011;18:835-43 pubmed publisher
    ..Baseline A/H1N1/2009-specific CD4? T-cell frequencies did not predict post-dose 1 antibody responses, but there was some correlation between post-dose 1 CD4? T-cell frequencies and post-dose 2 antibody responses. ..
  22. Nakaya H, Wrammert J, Lee E, Racioppi L, Marie Kunze S, Haining W, et al. Systems biology of vaccination for seasonal influenza in humans. Nat Immunol. 2011;12:786-95 pubmed publisher
    ..Thus, systems approaches can be used to predict immunogenicity and provide new mechanistic insights about vaccines. ..
  23. Lagler H, Wenisch J, Tobudic S, Gualdoni G, Rödler S, Rasoul Rockenschaub S, et al. Pandemic influenza A H1N1 vaccine in recipients of solid organ transplants: immunogenicity and tolerability outcomes after vero cell derived, non-adjuvanted, whole-virion vaccination. Vaccine. 2011;29:6888-93 pubmed publisher
    ..Our results show that the novel vero cell derived and adjuvant-free pandemic A/California/07/2009 (H1N1) influenza vaccine induced limited but measurable immune responses in adult recipients of solid organ transplants. ..
  24. Bickel M, von Hentig N, Wieters I, Khaykin P, Nisius G, Haberl A, et al. Immune response after two doses of the novel split virion, adjuvanted pandemic H1N1 influenza A vaccine in HIV-1-infected patients. Clin Infect Dis. 2011;52:122-7 pubmed publisher
    ..Among HIV-infected patients, the rate of seroconversion after the first dose of an adjuvanted H1N1 influenza A vaccine was 68% and increased to 92% after a second doses. ..
  25. Allwinn R, Geiler J, Berger A, Cinatl J, Doerr H. Determination of serum antibodies against swine-origin influenza A virus H1N1/09 by immunofluorescence, haemagglutination inhibition, and by neutralization tests: how is the prevalence rate of protecting antibodies in humans?. Med Microbiol Immunol. 2010;199:117-21 pubmed publisher
    ..Expecting the next waves of influenza A/H1N1v infections, HI testing may avoid vaccinations under special risk of severe or hidden adverse reactions. ..
  26. Alvarez M, López Pacheco F, Aguilar Yañez J, Portillo Lara R, Mendoza Ochoa G, García Echauri S, et al. Specific recognition of influenza A/H1N1/2009 antibodies in human serum: a simple virus-free ELISA method. PLoS ONE. 2010;5:e10176 pubmed publisher
    ..In addition, in a scenario of insufficient vaccine availability, the use of this ELISA could be useful to determine if a person has some level of specific antibodies against the virus and presumably at least partial protection. ..
  27. Skowronski D, Hottes T, Janjua N, Purych D, Sabaiduc S, Chan T, et al. Prevalence of seroprotection against the pandemic (H1N1) virus after the 2009 pandemic. CMAJ. 2010;182:1851-6 pubmed publisher
    ..These findings, particularly the low levels of seroprotection among people aged 50-79 years, should be confirmed in other settings and closer to the influenza season. ..
  28. Madhun A, Akselsen P, Sjursen H, Pedersen G, Svindland S, Nøstbakken J, et al. An adjuvanted pandemic influenza H1N1 vaccine provides early and long term protection in health care workers. Vaccine. 2010;29:266-73 pubmed publisher
    ..A rapid induction of protective antibody is important in reducing community spread of pandemic influenza and in helping maintain the integrity of the health care system during the pandemic...
  29. Chen M, Barr I, Koh G, Lee V, Lee C, Shaw R, et al. Serological response in RT-PCR confirmed H1N1-2009 influenza a by hemagglutination inhibition and virus neutralization assays: an observational study. PLoS ONE. 2010;5:e12474 pubmed publisher
    ..Appropriately timed paired serology detects 80-90% RT-PCR confirmed H1N1-2009; Antibodies from infection with H1N1-2009 cross-reacted with seasonal influenza viruses. ..
  30. Skountzou I, Koutsonanos D, Kim J, Powers R, Satyabhama L, Masseoud F, et al. Immunity to pre-1950 H1N1 influenza viruses confers cross-protection against the pandemic swine-origin 2009 A (H1N1) influenza virus. J Immunol. 2010;185:1642-9 pubmed publisher
  31. Manuel O, Pascual M, Hoschler K, Giulieri S, Alves D, Ellefsen K, et al. Humoral response to the influenza A H1N1/09 monovalent AS03-adjuvanted vaccine in immunocompromised patients. Clin Infect Dis. 2011;52:248-56 pubmed publisher
    ..A second dose of the vaccine only moderately improved vaccine immunogenicity in HIV-infected patients. ..
  32. Dowse G, Smith D, Kelly H, Barr I, Laurie K, Jones A, et al. Incidence of pandemic (H1N1) 2009 influenza infection in children and pregnant women during the 2009 influenza season in Western Australia - a seroprevalence study. Med J Aust. 2011;194:68-72 pubmed
    ..Augmented by vaccination, there should be sufficiently high levels of immunity in the Australian population to significantly reduce the impact of the virus in future influenza seasons. ..
  33. Vajo Z, Tamas F, Sinka L, Jankovics I. Safety and immunogenicity of a 2009 pandemic influenza A H1N1 vaccine when administered alone or simultaneously with the seasonal influenza vaccine for the 2009-10 influenza season: a multicentre, randomised controlled trial. Lancet. 2010;375:49-55 pubmed publisher
    ..It can be safely co-administered with the 2009-10 seasonal influenza vaccine. Omninvest, Hungary. ..
  34. Katz J, Hancock K, Xu X. Serologic assays for influenza surveillance, diagnosis and vaccine evaluation. Expert Rev Anti Infect Ther. 2011;9:669-83 pubmed publisher
    ..The use of standardized protocols and antibody standards are important steps to improve reproducibility and interlaboratory comparability of results of serologic assays for influenza viruses. ..
  35. Veguilla V, Hancock K, Schiffer J, Gargiullo P, Lu X, Aranio D, et al. Sensitivity and specificity of serologic assays for detection of human infection with 2009 pandemic H1N1 virus in U.S. populations. J Clin Microbiol. 2011;49:2210-5 pubmed publisher
    ..S. populations during the first pandemic waves. These studies provide an approach to optimize timely serological investigations for future pandemics or outbreaks of novel influenza viruses among humans. ..
  36. Schultsz C, Nguyen V, Hai L, Do Q, Peiris J, Lim W, et al. Prevalence of antibodies against avian influenza A (H5N1) virus among Cullers and poultry workers in Ho Chi Minh City, 2005. PLoS ONE. 2009;4:e7948 pubmed publisher
    ..This study provides additional support for the low transmissibility of clade 1 H5N1 to humans, but limited transmission to highly exposed persons cannot be excluded given the presence of low antibody titers in some individuals. ..
  37. Plennevaux E, Sheldon E, Blatter M, Reeves Hoché M, Denis M. Immune response after a single vaccination against 2009 influenza A H1N1 in USA: a preliminary report of two randomised controlled phase 2 trials. Lancet. 2010;375:41-8 pubmed publisher
    ..Safety and reactogenicity of the vaccine were acceptable and similar to those of seasonal vaccine. Office of the Assistant Secretary for Preparedness and Response, and Biomedical Advanced Research and Development Authority. ..
  38. Wu J, Zhong X, Li C, Zhou J, Lu M, Huang K, et al. Optimal vaccination strategies for 2009 pandemic H1N1 and seasonal influenza vaccines in humans. Vaccine. 2011;29:1009-16 pubmed publisher
    ..MN and ELISPOT assays showed a similar effect. Vaccination with pandemic H1N1 vaccine first is recommended to avoid an associated inhibitory effect by the seasonal trivalent flu vaccine. ..
  39. Booy R, Khandaker G, Heron L, Yin J, Doyle B, Tudo K, et al. Cross-reacting antibodies against the pandemic (H1N1) 2009 influenza virus in older Australians. Med J Aust. 2011;194:19-23 pubmed
    ..Pandemic influenza control measures need to focus more on younger adults naive to the pandemic virus and at increased risk of severe disease. ..
  40. Rizzo C, Rota M, Bella A, Alfonsi V, Declich S, Caporali M, et al. Cross-reactive antibody responses to the 2009 A/H1N1v influenza virus in the Italian population in the pre-pandemic period. Vaccine. 2010;28:3558-62 pubmed publisher
    ..5%, 19.2%, and 58.2%, respectively. The results suggest that the Italian population was not fully naïf to the current pandemic virus and that the possible previous exposure and immune response increases with age. ..
  41. Liang X, Wang H, Wang J, Fang H, Wu J, Zhu F, et al. Safety and immunogenicity of 2009 pandemic influenza A H1N1 vaccines in China: a multicentre, double-blind, randomised, placebo-controlled trial. Lancet. 2010;375:56-66 pubmed publisher
  42. Roman F, Vaman T, Gerlach B, Markendorf A, Gillard P, Devaster J. Immunogenicity and safety in adults of one dose of influenza A H1N1v 2009 vaccine formulated with and without AS03A-adjuvant: preliminary report of an observer-blind, randomised trial. Vaccine. 2010;28:1740-5 pubmed publisher
  43. Nolan T, McVernon J, Skeljo M, Richmond P, Wadia U, Lambert S, et al. Immunogenicity of a monovalent 2009 influenza A(H1N1) vaccine in infants and children: a randomized trial. JAMA. 2010;303:37-46 pubmed publisher
    ..One 15-microg dose of vaccine was immunogenic in infants and children starting at 6 months of age and vaccine-associated reactions were mild to moderate in severity. clinicaltrials.gov Identifier: NCT00940108. ..
  44. Loebermann M, Anders G, Brestrich G, Fritzsche C, Klammt S, Boršo D, et al. Safety and immunogenicity of a trivalent single dose seasonal influenza vaccine containing pandemic A(H1N1) antigen in younger and elderly subjects: a phase III open-label single-arm study. Vaccine. 2011;29:1228-34 pubmed publisher
    ..This single dose trivalent seasonal influenza vaccine generated protective antibodies to all three viral strains and had an acceptable safety profile in both younger and older adults (ClinicalTrials.gov identifier: NCT01147081). ..
  45. Ujike M, Shimabukuro K, Mochizuki K, Obuchi M, Kageyama T, Shirakura M, et al. Oseltamivir-resistant influenza viruses A (H1N1) during 2007-2009 influenza seasons, Japan. Emerg Infect Dis. 2010;16:926-35 pubmed publisher
    ..Our data indicate that the current vaccine or zanamivir and amantadine are effective against recent ORVs, but continuous surveillance remains necessary. ..
  46. Liu D, Si B, Li C, Mi Z, An X, Qin C, et al. Prokaryotic expression and purification of HA1 and HA2 polypeptides for serological analysis of the 2009 pandemic H1N1 influenza virus. J Virol Methods. 2011;172:16-21 pubmed publisher
    ..These results will aid future immunological and serological studies of the 2009 pandemic H1N1 virus HA. ..
  47. Ohfuji S, Fukushima W, Deguchi M, Kawabata K, Yoshida H, Hatayama H, et al. Immunogenicity of a monovalent 2009 influenza A (H1N1) vaccine among pregnant women: lowered antibody response by prior seasonal vaccination. J Infect Dis. 2011;203:1301-8 pubmed publisher
    ..A single dose of vaccine induced an adequately protective level of immunity in pregnant women. The potential interference with seasonal vaccination requires a more thorough investigation to prepare for future influenza pandemics. ..
  48. Sun Y, Bian C, Xu K, Hu W, Wang T, Cui J, et al. Immune protection induced on day 10 following administration of the 2009 A/H1N1 pandemic influenza vaccine. PLoS ONE. 2010;5:e14270 pubmed publisher
    ..Individuals with a stronger pre-existing seasonal influenza antibody response may have a relatively higher potential for developing a stronger humoral immune response after vaccination with the 2009 A/H1N1 pandemic influenza vaccine. ..
  49. Crum Cianflone N, Eberly L, Duplessis C, Maguire J, Ganesan A, Faix D, et al. Immunogenicity of a monovalent 2009 influenza A (H1N1) vaccine in an immunocompromised population: a prospective study comparing HIV-infected adults with HIV-uninfected adults. Clin Infect Dis. 2011;52:138-46 pubmed publisher
    ..Future studies evaluating a 2-dose series or more-immunogenic influenza A (H1N1) vaccines among HIV-infected adults are needed (ClinicalTrials.gov NCT00996970). ..
  50. Arankalle V, Virkar R, Tandale B, Ingle N. Utility of pandemic H1N1 2009 influenza virus recombinant hemagglutinin protein-based enzyme-linked immunosorbent assay for serosurveillance. Clin Vaccine Immunol. 2010;17:1481-3 pubmed publisher
    ..The results showed a concordance of 98.4%, suggesting the utility of the ELISA in serosurveillance. Two hundred sixty-nine (100%) serum samples with an HI titer of > or =20 were ELISA reactive. ..
  51. Hirota J, Nishi H, Matsuda H, Tsunemitsu H, Shimiz S. Cross-reactivity of Japanese encephalitis virus-vaccinated horse sera in serodiagnosis of West Nile virus. J Vet Med Sci. 2010;72:369-72 pubmed
    ..There was little difference between the JEV HI and WNV HI titers in individual horses. These results indicate that in serosurveillance of WNV, JEV-vaccinated horses can produce false-positive results in WNV IgG-ELISA, HI and PRNT. ..
  52. Lee V, Yap J, Tay J, Barr I, Gao Q, Ho H, et al. Seroconversion and asymptomatic infections during oseltamivir prophylaxis against Influenza A H1N1 2009. BMC Infect Dis. 2010;10:164 pubmed publisher
    ..Asymptomatic infections occur during prophylaxis, which may confer protection against future infection. Post-exposure prophylaxis is effective as a measure in mitigating pandemic influenza outbreaks. ..
  53. Waddington C, Walker W, Oeser C, Reiner A, John T, Wilkins S, et al. Safety and immunogenicity of AS03B adjuvanted split virion versus non-adjuvanted whole virion H1N1 influenza vaccine in UK children aged 6 months-12 years: open label, randomised, parallel group, multicentre study. BMJ. 2010;340:c2649 pubmed publisher
    ..This indicates the potential for improved immunogenicity of influenza vaccines in this age group. Clinical trials.gov NCT00980850; ISRCTN89141709. ..