scholarly journals Prevalence of Neutralising Antibodies to HCoV-NL63 in Healthy Adults in Australia

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1618
Author(s):  
Sean A. Lynch ◽  
Kanta Subbarao ◽  
Siddhartha Mahanty ◽  
Bridget E. Barber ◽  
Eileen V. Roulis ◽  
...  
Keyword(s):  
Immune Response ◽  
Blood Donors ◽  
Healthy Adult ◽  
Adult Population ◽  
Geometric Mean ◽  
Plasma Samples ◽  
Neutralising Antibodies ◽  
Human Coronavirus ◽  
Geometric Mean Titre ◽  
Antibody Titres

The COVID-19 pandemic has highlighted the importance of understanding the immune response to seasonal human coronavirus (HCoV) infections such as HCoV-NL63, how existing neutralising antibodies to HCoV may modulate responses to SARS-CoV-2 infection, and the utility of seasonal HCoV as human challenge models. Therefore, in this study we quantified HCoV-NL63 neutralising antibody titres in a healthy adult population using plasma from 100 blood donors in Australia. A microneutralisation assay was performed with plasma diluted from 1:10 to 1:160 and tested with the HCoV-NL63 Amsterdam-1 strain. Neutralising antibodies were detected in 71% of the plasma samples, with a median geometric mean titre of 14. This titre was similar to those reported in convalescent sera taken from individuals 3–7 months following asymptomatic SARS-CoV-2 infection, and 2–3 years post-infection from symptomatic SARS-CoV-1 patients. HCoV-NL63 neutralising antibody titres decreased with increasing age (R2 = 0.042, p = 0.038), but did not differ by sex. Overall, this study demonstrates that neutralising antibody to HCoV-NL63 is detectable in approximately 71% of the healthy adult population of Australia. Similar titres did not impede the use of another seasonal human coronavirus (HCoV-229E) in a human challenge model, thus, HCoV-NL63 may be useful as a human challenge model for more pathogenic coronaviruses.

scholarly journals SARS-CoV-2 neutralising antibody testing in Europe: towards harmonisation of neutralising antibody titres for better use of convalescent plasma and comparability of trial data

2021 ◽  
Vol 26 (27) ◽  
Author(s):  
Dung Nguyen ◽  
Peter Simmonds ◽  
Maurice Steenhuis ◽  
Elise Wouters ◽  
Daniel Desmecht ◽  
...  
Keyword(s):  
Trial Data ◽  
Plasma Samples ◽  
Antibody Testing ◽  
Neutralising Antibodies ◽  
Dilution Series ◽  
Standard Curve ◽  
Antibody Titres

We compared the performance of SARS-CoV-2 neutralising antibody testing between 12 European laboratories involved in convalescent plasma trials. Raw titres differed almost 100-fold differences between laboratories when blind-testing 15 plasma samples. Calibration of titres in relation to the reference reagent and standard curve obtained by testing a dilution series reduced the inter-laboratory variability ca 10-fold. The harmonisation of neutralising antibody quantification is a vital step towards determining the protective and therapeutic levels of neutralising antibodies.

Antibody response to feline herpesvirus-1 vaccination in healthy adult cats

2019 ◽  
Vol 22 (4) ◽  
pp. 329-338
Author(s):  
Michèle Bergmann ◽  
Stephanie Speck ◽  
Anna Rieger ◽  
Uwe Truyen ◽  
Katrin Hartmann
Keyword(s):  
Antibody Response ◽  
Neutralizing Antibodies ◽  
Healthy Adult ◽  
Neutralising Antibodies ◽  
Multivariate Statistical ◽  
Feline Herpesvirus ◽  
Antibody Titres ◽  
Herpesvirus 1 ◽  
Adult Cats ◽  
Privately Owned

Objectives Vaccination against feline herpesvirus-1 (FHV-1) is recommended for all cats. However, it is unknown how adult healthy cats with different pre-vaccination antibodies respond to FHV-1 vaccination in the field. The aim of the study was to determine the prevalence of neutralising antibodies against FHV-1 in healthy adult cats and the response to FHV-1 vaccination within 28 days of vaccination. Methods One hundred and ten cats (⩾1 year of age) that had not received a vaccination within the past 12 months were vaccinated with a combined FHV-1 vaccine. Antibodies against FHV-1 were determined before vaccination (day 0), on day 7 and day 28 by serum neutralisation test. Uni- and multivariate statistical analyses were used to determine factors associated with the presence of pre-vaccination antibodies and response to vaccination. Results Pre-vaccination neutralising antibody titres (⩾10) were present in 40.9% of cats (45/110; 95% confidence interval [CI] 32.2–50.3); titres were generally low (range 10–640). Antibody response to vaccination (⩾four-fold titre increase) was observed in 8.3% (9/109; 95% CI 4.2–15.1). Cats ⩾2 years of age were more likely to have pre-vaccination neutralising antibodies than cats aged between 1 and 2 years (odds ratio [OR] 24.619; P = 0.005). Cats from breeders were more likely to have pre-vaccination neutralising antibodies than privately owned cats (OR 7.070; P = 0.007). Domestic shorthair cats were more likely to have an at least four-fold titre increase vs purebred cats (OR 11.22; P = 0.027). Conclusions and relevance Many cats have no detectable neutralising antibodies against FHV-1 despite previous vaccinations and fail to develop a ⩾four-fold titre increase after vaccination. This is likely because older cats and cats with a higher FHV-1 exposure risk are more likely to get infected with FHV-1 and thus to have FHV-1 neutralizing antibodies. Purebred cats more often fail to develop a ⩾four-fold titre increase after vaccination.

scholarly journals Determination of immune response of imported Newcastle disease virus vaccines in broiler chickens

1970 ◽  
Vol 6 (2) ◽  
pp. 139-144
Author(s):  
MS Islam ◽  
AKM Khasruzzaman ◽  
MT Hossain ◽  
MT Islam ◽  
MH Chowdhury ◽  
...  
Keyword(s):  
Immune Response ◽  
Newcastle Disease ◽  
Broiler Chickens ◽  
Geometric Mean ◽  
Primary Vaccination ◽  
Unvaccinated Control ◽  
Antibody Titres ◽  
Newcastle Disease Vaccine ◽  
Group 1

A study was undertaken to determine the immune response of eight different imported live NDV vaccines in broiler chickens in the Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh during the period from July to December 2008. A total of 55 broiler chickens (Ross breed) were divided into eleven groups such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 of which group 1, 3, 5, 7 and 9 were vaccinated primarily with Nobilis® MA5+Clone30, Avipro® ND-IB HB1, Cevac® BIL, Newcastle-Bronchitis Vaccine Fortdodge® and Avipro® ND LaSota vaccine respectively at day 5 of age and secondarily with Nobilis® ND Clone 30, Avipro® ND LaSota, Cevac® New L, Newcastle Disease vaccine Fortdodge® and Avipro® ND LaSota vaccine respectively at day 21 of age by single eye instillation and 2, 4, 6, 8 and 10 were vaccinated with the same vaccines respectively by double eye instillation following the same schedule. Group 11 was kept as unvaccinated control. Sera samples were collected after 10 days of each vaccination and at day 5, 15, 20, 31 of age from nonvaccinated control and subjected to HI test for the determination of antibody titres. It was observed that after primary vaccination the geometric mean (GM) of HI titres of double eye vaccinated groups differed significantly (P

Immune response to hepatitis a vaccination in HIV-infected men in Greece

2012 ◽  
Vol 23 (7) ◽  
pp. 464-467 ◽  
Author(s):  
S Kourkounti ◽  
N Mavrianou ◽  
Va Paparizos ◽  
K Kyriakis ◽  
M Hatzivassiliou ◽  
...  
Keyword(s):  
Immune Response ◽  
Hepatitis A ◽  
Response Rate ◽  
Hepatitis A Virus ◽  
Seroconversion Rate ◽  
Geometric Mean ◽  
Blood Samples ◽  
Cd4 Counts ◽  
Increased Risk ◽  
Antibody Titres

HIV-infected patients are at increased risk for acquiring hepatitis A virus (HAV) infection. We evaluated the seroconversion rate (anti-HAV antibodies ≥ 20 mIU/ml) and the geometric mean antibody titres (GMTs) in a group of 351 HIV infected men, who had received two doses of a hepatitis A vaccine. We analysed blood samples collected at one, six, 12 and 18 months following the administration of the second dose of the vaccine. The seroconversion rate one month after the second dose of the vaccine was 74.4% (260/351). At month 18 after the end of vaccination, 56.1 % of the subjects remained seropositive. GMTs were 315, 203,153 and 126 mIU/ml at months 1,6, 12, and 18, respectively. Logistic regression revealed that the CD4 count is the only factor affecting response to vaccination ( P = 0.019). A higher response rate and higher GMTs were observed in patients with CD4 counts ≥500 cells/mm3 (76.6%) than in patients with CD4 counts 200–499 cells/mm3. In conclusion, even in patients with near-normal CD4 counts, the response to the hepatitis A vaccine is impaired.

scholarly journals Antibody levels toMycoplasma pneumoniaein sera collected from healthy blood donors of Wellington, New Zealand, during 1976–80

1986 ◽  
Vol 96 (2) ◽  
pp. 249-255 ◽  
Author(s):  
J. Pearce ◽  
K. Bettleheim ◽  
R. Metcalfe
Keyword(s):  
New Zealand ◽  
Blood Donors ◽  
Complement Fixation Test ◽  
Immune Status ◽  
Healthy Adult ◽  
Complement Fixation ◽  
Adult Population ◽  
Survey Period ◽  
High Prevalence ◽  
Antibody Levels

SUMMARYThe sera of healthy blood donors from the Wellington area of New Zealand, collected between 1976 and 1980, were analysed by the complement fixation test for antibody toMycoplasma pneumoniae. A high prevalence of antibody to this organism was demonstrated and the occurrence of anM. pneumoniaeepidemic in New Zealand within the survey period was shown to be reflected i the immune status of this healthy adult population. This would suggest that during an epidemic many people within the Wellington community may haveM. pneumoniaeinfections involving littl overt illness.

scholarly journals A review of leading COVID-19 vaccines, the quest for immune protection, and its key challenges. Part 3: Covid-19 vaccines – Key challenges and translational science

2021 ◽  
Author(s):  
Johan Hartshorne ◽  
Pierre Johannes Truter de Villiers
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Immune Responses ◽  
Common Cold ◽  
Herd Immunity ◽  
Immune Memory ◽  
Immune Protection ◽  
Neutralising Antibodies ◽  
Cell Responses ◽  
Antibody Titres

Rationale• Developing and deploying safe and effective COVID-19 vaccines are faced with many challenges and unanswered questions.• Massive amounts of heterogenic scientific data are being generated that are needed rapidly to advance vaccine development, protect people and restore normality. • The purpose of Part 3 of this four-part series is to review the scientific considerations related to key challenges associated with COVID-19 vaccines and immune protection with the focus of making this data more meaningful and open for clinicians.Key points• The primary immunogen (antigen) required to induce neutralising antibodies (humoral) and T cell (cellular) immune responses is the S-protein fragment of SARS-CoV-2. • Currently, the evidence is firmly pointing towards neutralising antibodies, being more critical for protection.• Long-term protective or durable immune memory is driven by virus-specific T cell and B cell responses (adaptive immunity).• Circulating antibody titres are not predictive of T cell immune memory.• Durable immune memory is a crucial factor to sustain herd immunity.• Adjuvants are added to certain vaccines to provoke a more robust and durable immune response.• Adjuvants that provoke TH1-biased immune responses are preferred. • 90% of adults are seropositive for 'common cold' CoV strains.• There is a cross-reactivity between specific T cell of SARS-CoV-2 and 'common cold' CoV's.• Prior infection with 'common cold' can play a potentially protective role.• Seropositive individuals present with a rapid and higher antibody immune response after a single dose with an mRNA vaccine.• Vaccine-induced immune responses resulting in non-neutralising antibodies, low antibody titres, and abnormal T cell responses (TH2- biased) are potential risks for serious enhanced disease events but unlikely events.• Vaccine strategies aimed at inducing high titres on neutralising antibodies and TH1- biased immune responses reduce the risk of serious adverse events.• Emerging variants of concern are extremely infectious, highly transmissible and threatens the protective efficacy of current vaccines.Public health implications• A rapid global vaccination campaign combined with standard mitigation measures to stop transmission is the best defence against the emergence of further SARS-CoV-2 variants and the safest way to attain herd immunity.• Booster immunisations may be required to promote or improve the durability and strength of vaccine immunity.

The Pandemic H1N1 Influenza Vaccine Results In Low Rates of Seroconversion In Patients with Hematological Malignancies

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3110-3110
Author(s):  
Katherine Monkman ◽  
James Mahony ◽  
Alejandro Lazo-Langner ◽  
Benjamin Chin-Yee ◽  
Leonard A. Minuk
Keyword(s):  
Influenza Vaccine ◽  
Hematological Malignancies ◽  
Geometric Mean ◽  
H1n1 Influenza ◽  
Pandemic H1n1 ◽  
Plasma Samples ◽  
H1n1 Vaccine ◽  
Post Vaccination ◽  
Fourfold Increase ◽  
Antibody Titres

Abstract Abstract 3110 Background: Patients with hematological malignancies are at increased risk of influenza and its complications. However, evidence for the efficacy of influenza vaccination in this population is limited and contradictory [Pollyea et al., J Clin Oncol. 2010]. The adjuvanted pandemic H1N1 vaccine has been shown to be highly effective in healthy adults, with reported rates of seroprotection and seroconversion of over 90% [Plennevaux et al., Lancet 2010]. We sought to determine whether patients being treated for hematological malignancies were able to mount a protective antibody response to the H1N1 pandemic influenza vaccine. Methods: Patients being treated for hematological malignancies at the London Regional Cancer Program during the 2009–2010 influenza season were invited to participate. Patients who had received the vaccine prior to the commencement of the study in November 2009 were excluded. Pre-vaccination plasma samples were collected in November 2009, and post-vaccination samples were collected from January through March 2010. At the time of second sample collection, patients were asked to complete a questionnaire asking if and when they had received the H1N1 influenza vaccine. Plasma samples from patients who elected not to be vaccinated formed a control group. Antibody titration was performed by the hemagglutinin inhibition test. Our primary outcome was the rate of seroconversion, as defined by a fourfold increase in antibody titres. We also measured geometric mean titres (GMT), geometric mean titre ratios, (GMTR, defined as the ratio of the post-vaccination titre to the pre-vaccination titre), and rates of seroprotection (titre ≥ 1:80). Statistical analysis was done using Mann-Whitney U, chi-squared, or Fisher's Exact Tests, as appropriate. Results: Sixty-two patients received the H1N1 vaccine and 41 patients chose not to be vaccinated. The rate of seroconversion among vaccinated patients was 21%, which was significantly higher than that in unvaccinated patients (0%) and significantly lower than that in healthy individuals. The GMTR was significantly higher in the vaccinated group than the unvaccinated group (2.2 ± 2.5 vs. 1.2 ± 0.6, p = 0.041). There were no significant differences in the geometric mean titres or the rates of seroprotection between the vaccinated and unvaccinated groups. Of the 46 patients on active chemotherapy who received the vaccine, 10 (22%) seroconverted and 16 (35%) mounted seroprotective titres. Of the 12 patients on active Rituximab who received the vaccine, 2 (17%) seroconverted and 4 (33%) mounted seroprotective titres. There were no significant differences in the rates of seroconversion and seroprotection between patients on or off chemotherapy or between patients on or off Rituximab. Conclusions: Only 21% of patients with hematological malignancies were able to produce a fourfold increase in antibody titres in response to the H1N1 influenza vaccine, a rate significantly lower than that previously reported for healthy patients. We were unable to identify any clinical factors predictive of a response to the vaccine. Physicians should be aware that patients with hematological malignancies are less likely to receive protection from the influenza vaccine, and should consider alternate strategies to minimize the morbidity and mortality from influenza in this population. Larger studies are indicated to confirm these results. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Low SARS-CoV-2 seroprevalence in blood donors in the early COVID-19 epidemic in the Netherlands

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ed Slot ◽  
Boris M. Hogema ◽  
Chantal B. E. M. Reusken ◽  
Johan H. Reimerink ◽  
Michel Molier ◽  
...  
Keyword(s):  
The Netherlands ◽  
High Performance ◽  
Blood Donors ◽  
Healthy Adult ◽  
Health Care Systems ◽  
Adult Population ◽  
Age Groups ◽  
The World ◽  
Care Systems ◽  
Affected Country

AbstractThe world is combating an ongoing COVID-19 pandemic with health-care systems, society and economies impacted in an unprecedented way. It is unclear how many people have contracted the causative coronavirus (SARS-CoV-2) unknowingly and are asymptomatic. Therefore, reported COVID-19 cases do not reflect the true scale of outbreak. Here we present the prevalence and distribution of antibodies to SARS-CoV-2 in a healthy adult population of the Netherlands, which is a highly affected country, using a high-performance immunoassay. Our results indicate that one month into the outbreak (i) the seroprevalence in the Netherlands was 2.7% with substantial regional variation, (ii) the hardest-hit areas showed a seroprevalence of up to 9.5%, (iii) the seroprevalence was sex-independent throughout age groups (18–72 years), and (iv) antibodies were significantly more often present in younger people (18–30 years). Our study provides vital information on the extent of exposure to SARS-CoV-2 in a country where social distancing is in place.

Sleep Habits and Sleep Patterns in Healthy Adult Population in Chennai

2012 ◽  
Vol 3 (5) ◽  
pp. 507-508
Author(s):  
Dr. M. Ganesh Dr. M. Ganesh ◽  
◽  
Dr.S.A.Sridevi Dr.S.A.Sridevi ◽  
Dr. T.Janagan Dr. T.Janagan
Keyword(s):  
Healthy Adult ◽  
Adult Population ◽  
Sleep Patterns ◽  
Sleep Habits
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