Mean Hemagglutination Inhibition Antibody Titers Research Articles

Arsenic and Immune Response to Influenza Vaccination in Pregnant Women and Newborns

Background/AimsThere is a gap in understanding of whether arsenic exposure during pregnancy alters the maternal immune response and antibody transfer to the infant. We aimed to establish a birth cohort in a region with low-moderate drinking water arsenic concentrations to investigate the relationship between arsenic exposure and immunogenicity of a seasonal quadrivalent inactivated influenza vaccine (IIV) in pregnant women and infants.MethodsWe established a birth cohort (NCT03930017) at the JiVitA Maternal and Child Health and Nutrition Research Project site, which covers ~650,000 people over 500 km2 in rural northern Bangladesh. We planned to enroll 850 pregnancies to achieve a desired sample size of 400 mother-infant pairs at three-months postpartum, based on minimum detectable differences in geometric mean hemagglutination inhibition antibody titers for seasonal quadrivalent IIV antigens when comparing the highest and lowest quartiles of arsenic exposure. From July 2018 to June 2019, we screened women of reproductive age to identify incident pregnancies. Multiparous pregnant women were enrolled in gestational weeks (GW) 13-16. At enrollment, we collected drinking water, urine, blood, and saliva, and administered IIV.ResultsWe screened 52,000 women to identify 2,623 incident pregnancies in multiparous women. Of these, 1,338 were identified prior to GW 16, 846 consented, and 784 enrolled. We followed 567 mother-infant pairs to three-months postpartum. At enrollment, all participants contributed drinking water, urine, blood (processed as plasma, serum, and peripheral blood mononuclear cells), and saliva. An analysis of 40 drinking water samples selected at random found that arsenic concentrations were comparable to arsenic-endemic regions of the U.S. (geometric mean: 3.03 µg/L, geometric standard deviation: 9.54 µg/L, range: 0.05 to 96.83 µg/L).ConclusionsThe number of pregnancies enrolled in our cohort yielded the sample size needed to investigate prespecified aims related to low-moderate arsenic exposure and altered maternal and child immune response.

Prospective cohort studies to evaluate the safety and immunogenicity of the 2013, 2014, and 2015 seasonal influenza vaccines produced by Instituto Butantan.

ABSTRACTAnnual vaccination is the most effective way to prevent seasonal influenza illness. Instituto Butantan (IB) performed clinical studies with its 2013, 2014 and 2015 seasonal trivalent influenza vaccines (inactivated split-virion). Prospective cohort studies were carried out to describe the safety and immunogenicity of Instituto Butantan influenza vaccines, in healthy adults and elderly, from 2013 to 2015. Immediately after the informed consent was signed, participants underwent blood collection followed by vaccination. On study days 1, 2 and 3 post-vaccination participants were contacted by the staff to evaluate the occurrence of solicited (local and systemic) and non-solicited adverse reactions. On study day 21 (+7) subjects returned to the clinical site for final safety assessments and blood collection to evaluate post-vaccination immunogenicity. The immunogenicity analyses were performed by means of hemagglutination inhibition (HI) assay. The immunogenicity endpoints were: seroprotection (SPR) and seroconversion (SCR) rates and the geometric mean HI antibody titer ratio (GMTR). The 2013 study was conducted at the Centro de Referência para Imunobiológicos Especiais (CRIE) and at the Centro de Pesquisa Clínica do Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo while the 2014 and 2015 studies were conducted at CRIE. The vaccine composition followed the WHO recommendation for the Southern hemisphere seasonal influenza vaccine. Forty-seven healthy adults and 13 elderly participated in the 2013 study, 60 healthy adults and 60 elderly in the 2014 study, and 62 healthy adults and 57 elderly in the 2015 study. In the 2013, 2014 and 2015 studies, pain was the most frequent local adverse reaction and headache the most frequent systemic adverse reaction. All observed adverse reactions were classified as mild or moderate and none as severe. SPR >70% and SPR >60% were observed in adults and elderly, respectively, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. SCR >40% was observed in adults, for the three vaccine viruses, only in the 2014 study and SCR >30% was observed in the elderly, for the three vaccine viruses, only in the 2013 and 2014 studies. GMTR >2.5 among adults, for the three vaccine viruses was only observed in the 2013 study and GMTR >2.0 was observed among elderly, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. The 2013, 2014 and 2015 seasonal influenza vaccines produced by Instituto Butantan were safe and immunogenic according to the immunogenicity criteria defined by the European Medicines Agency (EMA).

Effects of Vitamins E and C Supplementation on the Immune Response of Broiler Chicks

The present study was done to know the effects of supplementations of vitamin C and E on humoral immune response against Newcastle Disease (ND) and Infectious Bursal Disease (IBD) and on lymphoid organs in broiler birds. One hundred and twenty day old chicks were purchased from a local hatchery and were reared in an open house shed. On day 5th all the chick divided randomly into 4 groups A, B, C and D (30 birds in each). On the day 5th and 11th, the chicks were vaccinated against ND and Disease IBD. Booster doses of both vaccines were given on day 28. The chicks were offered Vitamin E (600 mg l-1), Vitamin C (600 mg l-1) and Vitamin E+C (300 mg l-1 each), for 5 consecutive days in drinking water on day 5 and 28. Weekly serum Hemagglutination Inhibition (HI) antibody titers against ND virus, total body weight, feed conversion ratio (FCR) and weight of lymphoid organs were recorded until the day 49. Geometric mean HI antibody titers against ND remained maximum in group C. Statistical analysis revealed a non significant (P<0.05) differences among the various treatment groups in weight gain. At day 49, the total weight gain was maximum in group C (2196.0 gm) followed by group A (2155.0 g), group B (2146 g) and group D (2094 gm). The feed conversion ratio was the best in the group B (1.66) followed by group C (1.69) with a non significant difference. From the study, it was concluded that the combined effect of Vitamin E+C was better as compared to separate supplementation of Vitamin E and Vitamin C.

Pathogenic Haemoparasites and Antibody to Newcastle Disease Virus from Apparently Healthy Wild Birds in Zaria, Nigeria

A total of ninety-eight wild birds, comprising eleven different species were captured alive from Zaria environs. These birds were used for the study, to determine the possible role they play as reservoirs of blood parasites. Thin blood smears (TBS) were prepared from the blood samples collected from these wild birds. The slides were stained and viewed under the microscope for the identification of blood parasites. Values of packed cell volume (PCV), haemoglobin (Hb) and total protein (TP) were also determined from the blood samples. Sera from the birds were used for the determination of haemagglutination inhibition (HI) antibody titres to Newcastle disease virus (NDV). Haemoparasites, such as Plasmodium circumflexum, P. relictum, P. nouxi, Haemoproteus nisi, H. columbae, and Aegyptienella pullorum were identified from the blood of some of the wild birds. The highest mean HI antibody titre to Newcastle disease virus( NDV) (log 9.50 ± 0.1) and lowest mean HI antibody titre to 2 NDV (log 2.50 ± 1.7) were obtained from Senegal parrot (Poicephalus senegalus) and Northern red bishop 2 (Euplectes franciscanus), respectively. The highest mean PCV and Hb values of 49.00 ± 0.01% and 16.30 ± 0.1g%, respectively were obtained from Senegal parrot (Poicephalus senegalus), while the lowest mean PCV and Hb values of 36.50 ± 8.35% and 12.18 ± 2.77g%, respectively were recorded from African marsked weaver (Ploceus velatus). The highest mean TP value (7.00 ± 0.01g/dl) and lowest mean TP value (1.88 ± 0.54g/dl) were obtained from Laughing dove (Streptopelia senegalensis) and Zebra waxbill (Sporaeginthus subflavus), respectively. It was concluded that wild birds could serve as reservoirs of haemoparasites and viral pathogens which could be potential dangers to domestic birds in Zaria, Nigeria.

Maternal immunity against avian influenza H5N1 in chickens: limited protection and interference with vaccine efficacy

After avian influenza (AI) vaccination, hens will produce progeny chickens with maternally derived AI-specific antibodies. In the present study we examined the effect of maternal immunity in young chickens on the protection against highly pathogenic AI H5N1 virus infection and on the effectiveness of AI vaccination. The mean haemagglutination inhibition antibody titre in sera of 14-day-old progeny chickens was approximately eight-fold lower than the mean titre in sera of vaccinated hens. After H5N1 infection at the age of 14 days, chickens with maternal antibody titres lived a few days longer than control chickens. However, only a low proportion of chickens with maternal immunity survived challenge with H5N1. In most progeny chickens with maternal immunity, high virus titres (>104 median embryo infective dose) were present in the trachea during the first 4 days after H5N1 infection. In the cloaca, only low virus titres were present in most chickens. In 14-day-old progeny chickens with maternal immunity, the induction of antibody titres by vaccination was severely inhibited, with only a few chickens showing responses similar to the control chickens. It is concluded that high maternal antibody titres are required for clinical protection and reduction of virus titres after infection of chickens, whereas low antibody titres already interfere with vaccine efficacy.

Antibody Responses Induced by Japanese Whole inactivated Vaccines against Equine Influenza Virus (H3N8) Belonging to Florida Sublineage Clade2

In 2010, the World Organisation for Animal Health recommended the inclusion of a Florida sublineage clade2 strain of equine influenza virus (H3N8), which is represented by A/equine/Richmond/1/07 (Richmond07), in equine influenza vaccines. Here, we evaluate the antigenic differences between Japanese vaccine strains and Richmond07 by performing hemagglutination inhibition (HI) assays. Ferret antiserum raised to A/equine/La Plata/93 (La Plata93), which is a Japanese vaccine strain, reacted with Richmond07 at a similar titer to La Plata93. Moreover, two hundred racehorses exhibited similar geometric mean HI antibody titers against La Plata93 and Richmond07 (73.1 and 80.8, respectively). Therefore, we can expect the antibody induced by the current Japanese vaccines to provide some protection against Richmond07-like viruses.

Clinico-Pathological Features of Newcastle Disease in Japanese Quails (Coturnix coturnix japonica) Infected with Newcastle Disease Virus Kudu 113 Strain

Experiments were performed to determine whether Japanese quails (Coturnix coturnix japonica) are susceptible to Newcastle disease virus (NDV) Kudu 113 strain. In the experimental trials, a total 119, six weeks old Japanese quails were administered varying doses of the virus, ranging from 0.1 ml to 0.3 ml intramuscularly (im) and per os (po). The uninfected control quails were not administered the virus and were reared separately. Depression, weakness, incoordination, anorexia, ruffled feathers and paralysis of legs and wings were noted in some of the infected quails. At necropsy, some of the infected quails also had haemorrhagic enteritis and congested lungs, liver, heart and spleen and muscles of breast, thighs and legs. There was a rise in haemagglutination inhibition (HI) antibody titre in all the infected quails, following administration of NDV Kudu 113 strain either im or po. The highest mean HI antibody titre of log 10.56± 0.29 2 was obtained on day seven post infection (pi) in the group that was administered 0.3 ml of the virus im. Similarly, the highest mean HI antibody titre of log 9.89±0.48 was obtained on day seven pi in quails that 2 were administered 0.3 ml of the virus po. On the other hand, the control quails were negative to HI antibody test. This study demonstrated that Japanese quails are susceptible to NDV Kudu 113 strain.

Vaccine-induced measles virus antibodies after two doses of combined measles, mumps and rubella vaccine: a 12-year follow-up in two cohorts

In Finland, a two-dose vaccination programme against measles, mumps and rubella (MMR) was begun in 1982. The programme with high coverage (97–98%) has eliminated these three diseases from Finland. The aim of the present study was to follow up the kinetics of measles virus antibodies in MMR vaccinated cohorts. We have followed the kinetics of measles virus antibody levels induced by vaccination in the same individuals immunized with their first MMR vaccine in 1982. After 12 years 80% of the original children remained available for sampling. Antibodies to measles virus were measured by haemagglutination inhibition (HI) and plaque reduction neutralization (NT) techniques. The primary dose induced 99.4% seroconversion for measles with a geometric mean HI antibody titre (GMT) of 1 269 (±219), equivalent to 4304 mIU (milli-International Units) ml −1 in group A. The 12-year follow-up specimens showed a measles seropositivity rate of 100% as assayed with the HI and NT tests with a mean HI antibody titre of 1 39 (±54), equivalent to 624 mIU ml −1. The vaccination-induced measles virus antibodies decline in the absence of natural booster infections. It is important to follow how long the protection achieved by the present vaccine programme will last after elimination of indigenous measles.

Seroepidemiological study on prevalence of measles antibodies in Urawa City.

To obtain a precise seroepidemiological understanding of measles antibodies, we analysed hemagglutination inhibition (HI) and neutralizing test (NT) antibodies in different age groups in Urawa City. We examined 1591 serum samples collected from subjects aged from zero day to 95 years. Of these 1591 samples, 1094 were HI antibody positive with a positive rate of 68.7%. Mean HI antibody titer by age was from 2(4.0 +/- 0.82) to 2(5.4 +/- 1.43). Of the 497 samples which were HI antibody negative, 419 were NT positive. HI antibody positive rate and mean antibody titer were decreased at ages 6 to 12 months, and then increased with age. Approximately 5% of school children aged 6 to 15 years were not immune status. The key issue for measles eradication is how to immunize this population.

Experimental Infection of Laying Chickens with Adenovirus 127 and with a Related Virus Isolated from Ducks

Infection of commercially reared white leghorn and white rock hens with adenovirus 127 was associated with decreases in total egg production, external egg quality, egg weight (P less than 0.01), and eggshell thickness (P less than 0.01). The egg-production and egg-quality disturbances were transient, and production returned to normal approximately 4 weeks postinfection. Infection of white leghorns with a hemagglutinating adenovirus isolated from Missouri ducks did not adversely affect egg production, external egg quality, or eggshell thickness, but it was associated with decreased egg weight (P less than 0.01). Prior infection with the duck adenovirus prevented the adverse egg-production effects of adenovirus 127 infection. Mean hemagglutination-inhibition antibody titers of chickens infected with adenovirus 127 or with duck adenovirus ranged from 1:588 to 1:10809, and mean titers of uninfected chickens did not exceed 1:2.

Vaccination of Broiler Chicks from Breeder Flocks Immunized with a Live or Inactivated Oil Emulsion Newcastle Disease Vaccine ,

One-day-old chicks used in this study were from breeder flocks vaccinated with live (B1 and LaSota) or inactivated oil emulsion Newcastle disease (ND) vaccine. Chicks were vaccinated against ND by various procedures. The vaccination response was evaluated by hemagglutination-inhibition antibody titers and by challenge. Chicks from breeder flocks vaccinated with live virus vaccine had a geometric mean hemagglutination-inhibition antibody titer (GMT) for Newcastle of 7 (low maternal antibody titer) at 1 day of age, whereas those chickens derived from breeder flocks vaccinated with inactivated oil emulsion ND vaccine had a GMT of 84 (high maternal antibody titer).One-day-old chicks injected with live B1 vaccine were not immunized against ND regardless of breeder flock source. However, chickens with low maternal antibody titers were effectively immunized against ND when injected at 1 day of age with an inactivated or inactivated plus live ND vaccine. Chicks with high maternal antibody titers were not effectively protected when vaccinated with inactivated vaccine at 1 day of age; however, these chicks were protected when injected with a combined live and inactivated ND vaccine.Chicks from both breeder flocks were effectively immunized against ND when injected at 1 day of age with a live or inactivated ND vaccine and revaccinated by aerosol at 21 days of age with live B1 ND vaccine. Even though they were protected against ND, there appears to have been an interference phenomenon in chicks derived from breeder flocks vaccinated with the live ND vaccine.Beak-O-Vac vaccinated chickens were not effectively protected against ND when compared with chicks vaccinated by aerosol at 1 day of age. Water vaccination at 7, 14, or 21 days of age was as effective as aerosol vaccination when administered to chicks with low maternal antibody titers. However, water vaccination was not as effective as aerosol vaccination when administered to chicks with high maternal antibody titers.

Further Studies with an Inactivated Oil Emulsion Newcastle Disease Vaccine in Broiler Breeders

Chickens vaccinated with a live Newcastle disease (ND) vaccine and subsequently revaccinated with an inactivated oil emulsion ND vaccine had higher and more persistent hemagglutination-inhibition (HI) antibody titers than birds vaccinated with live ND vaccine. The geometric mean HI antibody titers of flocks vaccinated with the inactivated ND vaccine ranged from 121 to 172, whereas the titers of flocks vaccinated every 90 days with a live ND vaccine ranged from 18 to 54.Breeder flocks revaccinated with live LaSota ND vaccine had lower egg production than the flocks vaccinated with inactivated vaccine. The average egg production per hen for the 40-week laying cycle was 174 and 170 eggs per hen for hens in the two houses vaccinated with the inactivated vaccine. Hens vaccinated with the live virus vaccine averaged 167 and 164 eggs per hen. The increase in egg production would more than offset the additional cost of the oil emulsion ND vaccine as well as the cost of injecting each individual bird at 18 weeks of age.Between 8 and 32 weeks after onset of egg production, geometric mean maternal antibody titers in 1-day-old chickens derived from breeders vaccinated with live ND vaccine ranged from 7 to 24, whereas, chicks from breeders vaccinated with the inactivated oil emulsion vaccine had maternal antibody titers that ranged from 64 to 89.

Pathogenicity of Two Strains of Mycoplasma gallisepticum in Turkeys

Strains F and R of Mycoplasma gallisepticum (MG) were compared in two laboratory trials for their relative pathogenicity in terms of inducing airsacculitis and antibody production to MG. Chickens exposed to the R strain had significantly higher incidence of air-sac lesions (P less than 0.05) and greater severity of airsacculitis than did chicks exposed to the F strain. In both trials, chickens vaccinated simultaneously with Newcastle disease-infectious bronchitis vaccine and exposed to MG had more severe lesions than did chickens exposed to mycoplasma alone. chickens exposed to the F strain had significantly lower geometric mean hemagglutination-inhibition antibody titers to MG than did chicks exposed to the R strain. Chickens vaccinated simultaneously with Newcastle disease-infectious bronchitis vaccine and exposed to R strain had significantly lower body weights than did chickens in the other group.

Immunogenic Potency of Oil-Emulsified Mycoplasma gallisepticum Bacterins

Immunogenicity of an aqueous Mycoplasma gallisepticum (MG) bacterin and two oil-emulsified bacterins with aqueous-phase-to-oil-phase ratios of 1:2 and 1:4 were evaluated in 3 groups of 5-week-old MG-free White Leghorn chickens. Group 4 chickens were nonimmunized controls. Group 1, 2, and 3 chickens received primary immunizations with 0.5 ml of bacterin subcutaneously (SC). Six weeks later, half of the vaccinated chickens received a second immunization (0.5 ml SC). Six weeks after the last dose of vaccine, all 4 groups of chickens were challenged intraocularly with a 24-hr broth culture of pathogenic MG ("R' strain). The geometric mean hemagglutination-inhibition antibody titers (GMT) of non-immunized, once-immunized, and twice-immunized chickens were compared at 2-week intervals following primary immunization, secondary immunization, and challenge. Both oil-emulsified bacterins stimulated significantly higher (P less than or equal to 0.05) levels of antibody than the aqueous bacterin after the primary and secondary immunizations. Following challenge with pathogenic MG, the GMT in the immunized and non-immunized chickens approached comparable values. The highest GMT in groups 1, 2, 3, and 4 respectively were: a) primary response, 19, 99, 121, and 11; b) secondary response, 105, 423, 793, and 21; and c) challenge response, 171, 278, 300, and 160. After challenge there was a further rise of antibody level in non-immunized chickens, those immunized with the aqueous bacterin, and those immunized only once with the oil-emulsified bacterins. This suggested a lack of protection against challenge. However, there was no increase of GMT in chickens immunized twice with the oil-emulsified bacterins.

Field Trials with an Oil Emulsion Newcastle Disease Vaccine in Broiler Breeders ,

Chickens vaccinated with live Newcastle disease (ND) vaccine and subsequently revaccinated with an inactivated oil emulsion vaccine had high and persistent hemagglutination-inhibition (HI) antibody titers for at least 40 weeks. The geometric mean HI antibody titers of flocks vaccinated with the inactivated ND vaccine ranged from 48.8 to 91.9, whereas the titers of flocks vaccinated every 90 days with a live ND vaccine ranged from 8.6 to 43.5.Breeder flocks revaccinated with a live LaSota ND vaccine had lower egg production than the flocks vaccinated with the inactivated vaccine. The average egg production per hen for the 40 week laying cycle was 177.8 and 174.8 eggs per hen for hens vaccinated with the inactivated vaccine, whereas those hens vaccinated with the live virus vaccine averaged 163.0 and 155.6 eggs per hen. The increase in egg production would more than offset the additional cost of the oil emulsion NDV vaccine as well as the cost of injecting each individual bird at point of lay.Maternal antibody titers in one-day-old chicks were related to the titers in the dams. Maternal antibody titers in chicks originating from breeder flocks vaccinated with the oil emulsion vaccine were higher than the maternal antibody titers of chickens from breeders vaccinated with the live NDV vaccine.

Immunization of Broiler Breeder Chickens against Newcastle Disease with an Oil-Emulsion Vaccine

Antibody response was rapid and high in broiler breeder chickens receiving 1 or 2 vaccinations with oil-emulsion vaccine against Newcastle disease at 23 or at 23 and 26 weeks old. The antibody titers remained high during the 41-week experimental period. At 64 weeks old, about 41 weeks after vaccination, the geometric mean hemagglutination-inhibition antibody titer was 67 from the single vaccination, and 103 from the double vaccination. The immune response to live-virus vaccine given at 2, 9, 20, 30, 42, or 54 weeks of age via the drinking water was high, but uniformity was lacking in the antibody response in the breeders and maternal antibody response in the progeny. Maternal antibody levels in one-day-old chicks were related to the titers of antibody in the dams. Maternal antibody titers of chicks originated from breeder flocks that were vaccinated with the oil-emulsion vaccine remained high for all hatches.

Comparative trials of live attenuated and detergent split influenza virus vaccines

Comparative clinical trials of live attenuated and detergent-split subunit influenza virus vaccines were undertaken with 1048 volunteers in Western Australia. Volunteers were divided into three main groups, each of which received either live virus vaccine or a saline control administered intranasally, or subunit vaccine injected subcutaneously. No differences were recorded between the three groups in their post-vaccination symptoms. Serum samples were collected at various times up to 50 weeks after vaccination, and antibody titres were measured by haemagglutination-inhibition (HI) tests and, for 231 volunteers, by virus neutralization tests. The two vaccines were almost equivalent in inducing seroconversion in vaccinees with pre-trial HI titres of 96 or less, but the subunit vaccine stimulated a higher geometric mean HI antibody titre. The longevity of the HI antibody response was greater for the live virus vaccine. The height of the response and the longevity of neutralizing antibody were the same for both vaccines. Both vaccines provided a high degree of protection against epidemic A/England/42/72 influenza, and some protection against A/Port Chalmers/1/73 influenza.

A Survey of Sheep Sera for Antibodies to an Ovine Strain of Parainfluenza 3 Virus

SUMMARY Five hundred serum samples, from sheep on thirty-five farms in Scotland and England, were tested for antibodies to an ovine strain of PI 3 virus. Two hundred and sixty-five were positive with a geometric mean haemagglutination inhibition antibody titre of 1/81. Evidence of PI 3 virus infection was detected in sheep from twenty-eight of the thirty-five flocks sampled.

Antibody response to Asian influenza vaccination in man.

SummaryThe route of administration, either intradermal, subcutaneous, or intramuscular, did not significantly affect the antibody response following Asian influenza vaccination. Antibody titers produced were proportional to the total amount of vaccine inoculated whether given as a single dose or divided into 2 injections separated by an interval of 3 weeks. Hemagglutination-inhibition antibody titers in post-vaccinal sera were greater when determined with the TC and EFME lines of Asian virus than with early or later passages of the straight E line. Neutralization titers with the TC line in monkey cultures were considerably greater than those determined with the E lines in the allantoic sac. The geometric mean hemagglutination-inhibition antibody titer of a large group of postinfluenzal sera was used as the baseline for evaluation of antibody response to vaccine by using the same virus line and method of in-activation of non-specific inhibitor in sera in both cases.