Whole-cell Vaccine Research Articles

IgM specific to lipopolysaccharide of Vibrio cholerae is a surrogate antibody isotype responsible for serum vibriocidal activity.

Serum vibriocidal antibody assays have long been used to evaluate the immunogenicity of cholera vaccines formulated with killed whole-cell Vibrio cholerae. However, the antibody isotypes responsible for the serum vibriocidal activity are not fully characterized. In this study, we examined 20 clinical serum samples obtained from human subjects who had been vaccinated with a killed, whole-cell cholera vaccine and a positive control, human convalescent sera with high vibriocidal activity, to determine which isotype antibody is associated with the vibriocidal activity. Antibody isotypes from pooled convalescent sera were fractionated by size-exclusion column chromatography, and the major vibriocidal activity was detected in the IgM fraction. Depletion of IgM antibodies in the convalescent sera produced a significant (P<0.05) decrease in vibriocidal activity (16-fold decrease), whereas only a small change was observed with depletion of IgG or IgA. In addition, anti-LPS IgM antibody showed the highest correlation with vibriocidal activity (Spearman correlation coefficient r = 0.846) among antibody isotypes against heat-killed V. cholerae, lipopolysaccharide (LPS), or major outer membrane protein (Omp U), while total IgG, IgA, or IgM antibody level was not correlated with vibriocidal activity in the 20 human clinical serum samples. Furthermore, human convalescent sera significantly (P<0.001) inhibited the attachment of V. cholerae to HT-29, a human intestinal epithelial cell in vitro. Interestingly, IgM-depleted convalescent sera could not effectively inhibit bacterial adherence compared with non-depleted sera (P<0.05). Finally, bacterial adhesion was significantly inhibited by sera with high vibriocidal titer compared with low-titer sera (P = 0.014). Collectively, we demonstrated that anti-V. cholerae LPS IgM is highly correlated with serum vibriocidal activity and it could be a surrogate antibody isotype representing protective antibodies against V. cholerae.

Evaluation of Pertussis Toxin Expression in B2 and THIJS Media.

Whole-cell pertussis vaccine (wP) has been imperative and highly effective in preventing childhood deaths due to pertussis. Pertussis toxin is one of the virulence factors of Bordetella pertussis in all available pertussis vaccines. wP production in Razi Vaccine and Serum Research Institute is according to bioreactor culture of B. pertussis strains in B2 medium. The aim of this study was to evaluate B. pertussis strain 509 PT production in B2 and Thalen-IJssel (THIJS) media by Chinese Hamster Ovary (CHO) cell and enzyme-linked immunosorbent assay methods (ELISA). In the current study, B. pertussis strain 509 was cultured in B2 and THIJS media. Six samples were taken during the log growth phase within 2-3 h intervals (triplicate). The growth rate was calculated using opacity and the quantification of cell-associated and released PT measured by ELISA and CHO cell assays. THIJS medium was significantly showed an increase in the bacterial growth rate. During the first 29 h, bacterial concentrations in B2 and THIJS culture medium were 19 and 29 IOU, respectively. In THIJS medium, greater amount of pertussistoxin production was cell-associated. In B2 medium, maximum cell-associated toxin by ELISA and CHO cell assays were in the ODs of 1.1 and 0.9 and for THIJS medium in the ODs of 1.6 and 1.1, respectively. B. pertussis strain 509 in THIJS medium produced higher cell mass and cell-associated pertussis toxin than that of B2. It can be used for the production of whole-cell vaccine with higher pertussis toxin and accordingly using lower biomass per dose leading to the reduction of vaccine toxicity.

Mathematical modelling to characterise the in vivo dynamics of Salmonella in the naïve and immunised host

Systemic salmonellosis encompasses typhoid and paratyphoid fever, and invasive non-typhoidal salmonellosis, with high mortality and morbidity amongst children and the immunocompromised in low-resource settings. Immunisation efforts remain hampered by the unavailability of safe vaccines with cross-protectivity against causative Salmonella strains. Characterisation of the within-host Salmonella dynamics in the naïve and immunised host can elucidate the mechanisms by which different vaccine types exert their protective effect, and help in vaccine selection and design. Experimental data tracking the changes in bacterial population composition in the different tissues of the host at different timepoints can be coupled with mechanistic mathematical models to estimate the parameters governing the processes of bacterial replication, killing and inter-organ migration. Using a recently described minimisation-divergence estimation approach, we extend a three-compartmental mechanistic model and re-analyse existing datasets to better characterise the bacterial migratory processes between the blood, liver and spleen in the early stages of infection, and the overall Salmonella dynamics in the later phases in the naïve host. We apply the same model to published data from mice immunised with either a live-attenuated or killed whole-cell vaccine to identify their in vivo differential impacts on Salmonella migration, replication and death. Finally, we identify alternative experimental designs to improve the statistical qualities of the mathematical model and allow better inference of parameters governing the unobserved processes of bacterial dynamics.

Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice.

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a striking increase in life expectancy around the globe. Nonetheless, determining vaccine efficacy remains a challenge. Emerging evidence suggests that the current acellular vaccine (aPV) for Bordetella pertussis (B. pertussis) induces suboptimal immunity. Therefore, a major challenge is designing a next-generation vaccine that induces protective immunity without the adverse side effects of a whole-cell vaccine (wPV). Here we describe a protocol that we used to test the efficacy of a promising, novel adjuvant that skews immune responses to a protective Th1/Th17 phenotype and promotes a better clearance of a B. pertussis challenge from the murine respiratory tract. This article describes the protocol for mouse immunization, bacterial inoculation, tissue harvesting, and analysis of immune responses. Using this method, within our model, we have successfully elucidated crucial mechanisms elicited by a promising, next-generation acellular pertussis vaccine. This method can be applied to any infectious disease model in order to determine vaccine efficacy.

Hydrogen peroxide-inactivated bacteria induces potent humoral and cellular immune responses and releases nucleic acids

The problem of nosocomial infection is seriously escalating. Bacterial vaccines are indispensable for preventing infections caused by multi-drug resistant organisms. Some researchers have put forward the use of hydrogen peroxide (H2O2) as a new technology platform for virus deactivation. This deactivated virus can induce the number of CD8+ T lymphocytes, which can enhance antiviral responses. Although, H2O2 treatment has been rarely reported on the exploration of bacterial deactivation, H2O2 deactivation of whole-cell bacteria could be a potential novel approach for bacterial vaccine development. Here we present a strategy for H2O2-deactivated bacterial whole-cell vaccines, for two major pathgens, Pseudomonas aeruginosa and Staphylococcus aureus. The proactive effects of vaccination were assessed in vitro and in vivo.H2O2-deactivation of bacterial vaccines retains more complete epitopes and exhibits lower toxicity, as compared to formaldehyde, a conventional deactivator that was investigated in this study. Furthermore, H2O2-deactivated bacterial vaccines induce anti-infection responses through enhancement of humoral immunity and cellular immunity. Vaccination with H2O2-deactivated whole-cell bacteria in mice mainly elicits whole-cell specific antibody titers and balances the IgG2a and IgG1 response, predominantly with IgG3 induction at the later stages, meanwhile provides opsonic protection against challenge with pathogens. Finally, H2O2 deactivation of bacteria has been found to cause the release of bacterial DNA which is followed by NF-κB activation. These findings demonstrate that the deactivation of whole-cell bacteria with H2O2 is potentially advantageous for immune responses. Considering the prevention of drug-resistant infections, this deactivation method could be simultaneously applied as an innovative strategy for bacterial vaccine development.

Promiscuous Coxiella burnetii CD4 Epitope Clusters Associated With Human Recall Responses Are Candidates for a Novel T-Cell Targeted Multi-Epitope Q Fever Vaccine.

Coxiella burnetii, the causative agent of Q fever, is a Gram-negative intracellular bacterium transmitted via aerosol. Regulatory approval of the Australian whole-cell vaccine Q-VAX® in the US and Europe is hindered by reactogenicity in previously exposed individuals. The aim of this study was to identify and rationally select C. burnetii epitopes for design of a safe, effective, and less reactogenic T-cell targeted human Q fever vaccine. Immunoinformatic methods were used to predict 65 HLA class I epitopes and 50 promiscuous HLA class II C. burnetii epitope clusters, which are conserved across strains of C. burnetii. HLA binding assays confirmed 89% of class I and 75% of class II predictions, and 11 HLA class II epitopes elicited IFNγ responses following heterologous DNA/DNA/peptide/peptide prime-boost immunizations of HLA-DR3 transgenic mice. Human immune responses to the predicted epitopes were characterized in individuals naturally exposed to C. burnetii during the 2007–2010 Dutch Q fever outbreak. Subjects were divided into three groups: controls with no immunological evidence of previous infection and individuals with responses to heat-killed C. burnetii in a whole blood IFNγ release assay (IGRA) who remained asymptomatic or who experienced clinical Q fever during the outbreak. Recall responses to C. burnetii epitopes were assessed by cultured IFNγ ELISpot. While HLA class I epitope responses were sparse in this cohort, we identified 21 HLA class II epitopes that recalled T-cell IFNγ responses in 10–28% of IGRA+ subjects. IGRA+ individuals with past asymptomatic and symptomatic C. burnetii infection showed a comparable response pattern and cumulative peptide response which correlated with IGRA responses. None of the peptides elicited reactogenicity in a C. burnetii exposure-primed guinea pig model. These data demonstrate that a substantial proportion of immunoinformatically identified HLA class II epitopes show long-lived immunoreactivity in naturally infected individuals, making them desirable candidates for a novel human multi-epitope Q fever vaccine.

The Resurgence of Measles, Mumps, and Pertussis

Although vaccines are one of the greatest scientific innovations to prevent disease and promote well-being, 1 in 10 children is not being vaccinated. This has directly contributed to the rise in vaccine-preventable diseases. Because of the high contagiousness of measles, mumps, and pertussis, innovative efforts are paramount to prevent disease outbreaks in the United States and worldwide. This article reviews measles, mumps, and pertussis; explains the resurgence of these vaccine-preventable diseases; and offers evidence-based solutions for increasing vaccination rates.

Does the economic recession influence the incidence of pertussis in a cosmopolitan European city?

BackgroundIn the last few years, pertussis has re-emerged worldwide. The aim of this article is to study how the incidence of the disease has evolved in Barcelona city over a 16-year period, and determine which factors are associated with the evolution of the disease. We discuss the causes of the observed changes considering different possibilities such as vaccination coverage, vaccine effectiveness, increased surveillance or the effect of the current economic recession.MethodsWe performed a cross-sectional, observational, population-based descriptive study using data for the 2000–2015 period from the notifiable diseases register maintained by Barcelona Public Health Agency. We used Poisson regression to compute adjusted odds ratios (aOR) and their corresponding 95% confidence intervals (CI).ResultsA total of 1791 cases were registered. The incidence of the disease increased throughout the city from 2011 onwards. While children under 1 year of age had the highest-incidence and were the most at risk (aOR = 27.18, CI:23.51–31.44), we found that the age of affected children was higher in the last years. Incidence proportion (PRR) was lower among foreign-born children than native children (PRR = 0.43 CI:0.32–0.58). In the whole-cell vaccine period (2000–2004), the percentage of cases under 1 year of age who received the vaccine was lower than in 2005–2015 when the acellular vaccine was used (p = 0.01), suggesting a lower efficacy of the acellular vaccine. However, vaccination coverage in children under 6 years remained high (~ 90%), and there were no significant year-to-year variations (p = 0.757). Moreover, there did not appear to be any significant restrictions in medical care. According to the index of disposable household income (DHI), pertussis incidence increased from 2011 onwards in all neighbourhoods and remained higher in those with lower DHI.ConclusionsThe noteworthy increase in pertussis incidence does not seem to be due to the economic recession, but to other factors here described.

Abstract B130: Induced lymphangiogenesis enhances antigen-specific T-cell response in anticancer vaccination

Abstract Tumor-associated lymphatic vessels play multiple and complex roles in the regulation of antitumor immunity. In both mouse and human melanomas, lymphatic markers correlate with increased tumor immune infiltrates and enhanced responsiveness to immunotherapy. Despite the immune-promoting functions of lymphatics in cancer immunotherapy, manipulation of lymphatic vessels directly within the tumor site appears controversial as a therapeutic strategy, due to the correlation of tumor lymphatic growth (lymphangiogenesis) with cancer cell dissemination and metastasis. Here, we sought to manipulate and exploit lymphatic vessels remotely from the tumor by developing and characterizing a lymphangiogenic cancer vaccine. Lymphangiogenic whole-cell vaccines were formulated using lethally irradiated tumor cells overexpressing the pro-lymphangiogenic growth factor VEGF-C in combination with topically retained immune adjuvants (VEGFC vax). In the B16F10 and B16F10-OVA mouse melanoma models, VEGFC vax induced extensive lymphatic growth at the cutaneous injection site, as assessed by both flow cytometry and histologic analysis. Induced lymphangiogenesis increased the rate of fluorescent microbead transport from the skin to the draining lymph nodes, suggesting an enhanced antigen trafficking. In addition, VEGF-C overexpression drove the recruitment in the vaccine injection site of naïve T-cells (responsive to lymphatic-derived CCL21), which could be primed in situ. Compared to a control VEGF-C-free vaccine formulation, VEGFC vax induced a broader T-cell response targeting multiple mouse melanoma antigens (including tumor neoantigens), as assessed by IFNγ ELISPOT following antigen-specific stimulation. In a prophylactic setting, VEGFC vax provided complete protection against B16F10 melanoma challenge, outperforming both the control vaccine and a GM-CSF-secreting whole-cell vaccine (GVAX). Overall this study provides a proof of concept for the use of VEGF-C as an immunostimulatory agent in cancer vaccines, based on its ability to activate and expand lymphatic vessels and consequently promote local immune cell trafficking, antigen transport and T-cell activation. In addition, we here developed and characterized a whole-cell VEGF-C vaccine formulation with potential for clinical translation. Citation Format: Maria Stella Sasso, Sylvie Hauert, Priscilla Briquez, Yue Wang, Jun Ishihara, Jeffrey A. Hubbell, Melody A. Swartz. Induced lymphangiogenesis enhances antigen-specific T-cell response in anticancer vaccination [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr B130.

Bivalent oral cholera vaccination induces a memory B cell response to the V. cholerae O1-polysaccharide antigen in Haitian adults

The bivalent killed whole-cell oral cholera vaccine (BivWC) is being increasingly used to prevent cholera. The presence of O-antigen-specific memory B cells (MBC) has been associated with protective immunity against cholera, yet MBC responses have not been evaluated after BivWC vaccination. To address this knowledge gap, we measured V. cholerae O1-antigen MBC responses following BivWC vaccination. Adults in St. Marc, Haiti, received 2 doses of the BivWC vaccine, Shanchol, two weeks apart. Participants were invited to return at days 7, 21, 44, 90, 180 and 360 after the initial vaccination. Serum antibody and MBC responses were assessed at each time-point before and following vaccination. We observed that vaccination with BivWC resulted in significant O-antigen specific MBC responses to both Ogawa and Inaba serotypes that were detected by day 21 and remained significantly elevated over baseline for up to 12 months following vaccination. The BivWC oral cholera vaccine induces durable MBC responses to the V. cholerae O1-antigen. This suggests that long-term protection observed following vaccination with BivWC could be mediated or maintained by MBC responses.

Seventy Years of Chlamydia Vaccine Research – Limitations of the Past and Directions for the Future

Chlamydia is a major bacterial pathogen that infects humans, as well as a wide range of animals, including marsupials, birds, cats, pigs, cattle, and sheep. Antibiotics are the only treatment currently available, however, with high rates of re-infection, there is mounting pressure to develop Chlamydia vaccines. In this review, we analyzed how Chlamydia vaccine trials have developed over the past 70 years and identified where future trials need to be focused. There has been a strong bias toward studies targeting C. muridarum and C. trachomatis within mice and a lack of studies matching chlamydial species to their end target host. Even though a large number of specific antigenic targets have been studied, the results from whole-cell vaccine targets show slightly more promising results overall. There has also been a strong bias toward systemic vaccine delivery systems, despite the finding that mucosal delivery systems have shown more promising outcomes. However, the only successful vaccines with matched chlamydial species/infecting host are based on systemic vaccine delivery methods. We highlight the extensive work done with mouse model trials and indicate that whole cell antigenic targets are capable of inducing an effective response, protecting from disease and reducing shedding rates. However, replication of these results using antigen preparations more conducive to commercial vaccine production has proven difficult. To date, the Major Outer Membrane Protein (MOMP) has emerged as the most suitable substitute for whole cell targets and its delivery as a combined systemic and mucosal vaccine is most effective. Finally, although mouse model trials are useful, differences between hosts and infecting chlamydial strains are preventing vaccine formulations from mouse models to be translated into larger animals or intended hosts.

Macrophage Foam Cell-Targeting Immunization Attenuates Atherosclerosis.

Background: Macrophage foam cells (FCs) play a crucial role in the initiation and progression of atherosclerosis. Reducing the formation or inducing the removal of FCs could ameliorate atherosclerosis. The present study examined whether the whole-cell vaccination using FCs could be used as novel prevention and treatment strategies to battle atherosclerosis.Methods: ApoE−/− mice with initial or established atherosclerosis were subcutaneously immunized three times with FCs in Freund's adjuvant.Results: Immunization with FCs resulted in an overt reduction of atherosclerotic lesion in the whole aorta and the aortic root with enhanced lesion stability. Subsequent study in mechanism showed that FCs vaccination dramatically increased CD4+ T cell and CD8+ T cell populations. Immunization with FCs significantly raised the plasma FCs-specific IgG antibodies. Of note, the FCs immune plasma could selectively recognize and bind to FC. FCs immune plasma significantly blocked the process of FCs formation, finally reduced the accumulation of FCs in plaque. Additionally, it was observed that FCs immunization down-regulated the expression level of atherosclerosis related pro-inflammatory cytokines, including IFN-γ, MCP-1, and IL-6 and enhanced the lesion stability with a significant increase in TGF-β1 level and collagen content.Conclusions: These findings demonstrate that the whole-cell vaccination using FCs significantly decreased lesion development and positively modulated lesion progression and stability by targeting FCs. The whole-cell FCs vaccine might represent a potential novel strategy for development of new antibodies and vaccines to the prevention or treatment of atherosclerosis.

Clinical study of safety and immunogenicity of pentavalent DTP-HB-Hib vaccine administered by disposable-syringe jet injector in India

IntroductionWe conducted a randomized, observer-blind, non-inferiority, parallel-group clinical study of diphtheria, tetanus, pertussis, hepatitis B, and Haemophilus influenzae type b conjugate (pentavalent) vaccination of infants in India. Goals were to determine whether the seropositivity rate after vaccination via disposable-syringe jet injector (DSJI) was non-inferior to that via needle and syringe (N-S), and to compare the safety of vaccination by the two methods.MethodsHealthy children received a three-dose series of vaccine intramuscularly by DSJI or N-S beginning at 6–8 weeks of age. Immunoglobulin G antibody levels were measured by ELISA at 4–6 weeks after the third dose. The main secondary endpoint was safety, measured as injection site and systemic reactions.DiscussionThe study was stopped early out of caution beyond that specified in the protocol stopping criteria, after the Data Safety Committee noted a higher frequency of injection site reactions, especially moderate and severe, in the DSJI group. As a result, 128 subjects—DSJI group 61; N-S group 67—completed the study, rather than the 340 planned, and the study was not sufficiently powered to compare immunogenicity endpoints for the groups. Descriptive statistics indicate that seropositivity induced by vaccination with the DSJI was similar to that of N-S for all five antigens. Pentavalent vaccine includes whole-cell pertussis vaccine and an aluminum adjuvant, which may have contributed to the higher number of local reactions with the DSJI. The reactions caused no serious or long-term sequelae, and may be more acceptable in other populations or circumstances.US National Institutes of Health clinical trials identifier: NCT02409095.

History and Prospect of Vaccines Against Pertussis

Pertussis, known as whooping cough, is a severe respiratory disease most commonly caused by the bacterium Bordetella pertussis. It is transmitted from person to person by aerosols and infects the ciliated epithelium of the airways. Pertussis was responsible for high mortality rates before the introduction of effective vaccines in the second half of the 20th century. Vaccination is thought to be the most effective method for control pertussis. There have been two types of pertussis vaccines available. The first-generation vaccine was the whole-cell vaccine, which was efficacious. However, it caused occasional side effects. The whole-cell vaccine was gradually replaced by the acellular vaccine. The acellular vaccine consists of detoxified, purified pertussis antigens. Despite the widespread use of the acellular vaccine, pertussis has recently been on the rise. In order to overcome such a situation, developments of new pertussis vaccines are in progress over the world. One is a genetically modified live vaccine which is thought to maintain safety while inducing immunity close to natural infection. And also there are a mucosal vaccine using lactic acid bacteria carrying components of pertussis and a bacterium-like particle vaccine with components of pertussis. In this review we introduce history and prospect of vaccines against pertussis.

Population dynamics and antigenic drift of Bordetella pertussis following whole cell vaccine replacement, Barcelona, Spain, 1986–2015

ABSTRACT Among the factors associated with the resurgence of whooping cough, special emphasis has been given to pathogen adaptation after the introduction of the acellular vaccine (ACV). To assess the impact of the vaccine transition strategy from whole-cell vaccine (WCV) to ACV on population dynamics of Bordetella pertussis in Barcelona (Spain), we studied 339 isolates collected from 1986 to 2015 by PFGE and multi-locus variable-number tandem repeat analysis (MLVA). Additionally, allelic variants for the pertussis toxin and its promoter, pertactin, type 3 fimbriae and fimbrial serotyping were assessed to determine its antigenic drift. A shift was observed in the B. pertussis population as well as in its antigenic profile concurrently with the introduction of ACV in Barcelona. Four out of the five most prevalent PFGE profiles were replaced by new profiles following the ACV introduction. MLVA type 27 was the dominant genotype, and its frequency increased from 25% to 79.3% after WCV replacement. Antigen typing demonstrated the emergence of prn2, ptxP3, fim3-2 and a shift from the fimbriae 3 to the fimbriae 2 serotypes after the ACV introduction. Our findings support the presence of population and antigenic dynamic changes in B. pertussis likely driven by the introduction of ACV.

Human Immune Responses to Pertussis Vaccines.

Pertussis still represents a major cause of morbidity and mortality worldwide. Although vaccination is the most powerful tool in preventing pertussis and despite nearly 70years of universal childhood vaccination, incidence of the disease has been rising in the last two decades in countries with high vaccination coverage. Two types of vaccines are commercially available against pertussis: whole-cell pertussis vaccines (wPVs) introduced in the 1940s and still in use especially in low and middle-income countries; less reactogenic acellular pertussis vaccines (aPVs), licensed since the mid-1990s.In the last years, studies on pertussis vaccination have highlighted significant gaps and major differences between the two types of vaccines in the induction of protective anti-pertussis immunity in humans. This chapter will discuss the responses of the immune system to wPVs and aPVs, with the aim to enlighten critical points needing further efforts to reach a good level of protection in vaccinated individuals.

Pertussis in Poland in 2017

After the introduction of compulsory pertussis vaccination in Poland in 1960, there was a sharp decline in the incidence of this disease. For several years, however, an increase in the number of reported cases has been observed. In 2015 and 2016, the incidence was 12.9 and 17.8 per 100 000 population, respectively (1). The year 2017 can be treated as an inter-epidemic year in which there was a significant decrease (by 55.1%) incidence to 8.0 per 100 000 population compared to the previous year. Pertussis who are still old who may be the source of infection for non-immunized or not fully immunized newborns and infants are still a high percentage. Vaccination in accordance with the current calendar remains the most effective strategy for preventing illness. In our country, research is being carried out to optimize pertussis vaccination schedules using both whole-cell and acellular vaccines. The aim of the study is to assess the epidemiological situation of pertussis in Poland in 2017 compared to the situation in previous years, with particular emphasis on assessing the vaccination status of children against pertussis. The assessment of the epidemiological situation of pertussis in Poland was carried out on the basis of the results of the analysis of individual reports of suspected pertussis cases sent to NIZP-PZH by provincial sanitary-epidemiological stations and data from the bulletin ‘Infectious diseases and poisoning in Poland in 2017’ (2) and the bulletin ‘Protective vaccinations in Poland in 2017’ (3). In 2017, 3 061 pertussis cases were recorded. The incidence was 8.0 per 100 000 population and was 55% lower than in the previous year (17.8). The highest incidence of pertussis occurred in persons in the age group 0-4 years (37.0), and high in children and adolescents aged 5-9 and 10-14 years - 21.4 and 25.7 per 100 000 population. From 3 061 pertussis patients, 762 people (i.e. 25%) were hospitalized. In 2017, no deaths from pertussis were reported. The number of pertussis cases observed in 2017 indicates the persistent circulation of bacteria in the environment and the persistent susceptibility of the population to infection. Still, the only effective strategy to reduce the number of cases of vaccination remains the use of vaccinations according to the current calendar and expert recommendations.

Pertussis Vaccines and Vaccination Strategies. An Ever-Challenging Health Problem.

Vaccines and vaccination against pertussis (whooping cough) have had one of the longest and most complex history, with alternating splendour and public disbelief, enthusiasm and concerns, overall resulting in changes in composition and replacement of vaccines, and associated vaccination strategies, including use of different vaccines in different countries, with no apparent equals for other bacterial vaccines. Of this both frustrating and exciting venue no end has been reached. In this note, I am shortly recapitulating the history of pertussis vaccines, from the inactivated, whole-cell vaccine to the acellular ones, with their merits and limitations, particularly concerning the debated issue of waning immunity, and a glimpse on a new vaccine proposal. Some reflections on the complexity and apparent peculiarity of this field are also made to the final scope of discussing aspects of the evolving strategies of disease control in a high-income country.

Advancements In Developing Anti-Campylobacter Vaccine For Poultry

Abstract Campylobacter jejuni/coli is the leading bacterial cause of diarrhoea in humans in both developing and developed countries. Epidemiological studies show that most cases of campylobacteriosis are the result of the consumption of undercooked, contaminated poultry meat. Although campylobacteriosis is largely a self-limiting disease with low mortality, a specific treatment is required for patients infected with strains resistant to clinically important antibiotics and for patients who develop neurological symptoms or bacteremia in course of infection. Despite intensive efforts to improve an on-farm biosecurity practice over the past decade, about 70% of EU broiler chicken flocks remain Campylobacter-positive at slaughter. Control of spreading the Campylobacter infection in flocks of chickens by biosecurity actions turned out rather ineffective. The most efficient strategy to decrease the number of human Campylobacter infections may be to implement an immunoprophylactic method, namely, the protective vaccination of chickens. The publication presents the current state of knowledge on anti-Campylobacter immunoprophylaxis in poultry. 1. Campylobacteriosis – epidemiological data, disease symptoms. 2. Campylobacteriosis – source of infection. 3. Campylobacteriosis – prophylaxis. 4. Immunization of chicken. 4.1. Passive immunization. 4.2, Campylobacter Whole-cell Vaccines. 4.3. Subunit vaccines. 5. Strategies for developing modern subunit vaccines. 5.1 Searching for antigen. 5.2. The choice of a carrier. 6. Modulation of immune response. 7. The route of antigen administration. 8. Summary

Estimation of Consistency of Production of the Pertussis Component of DTP Vaccine in Terms of Immunogenic Activity and Specific Safety Using Shewhart Charts

WHO experts attribute the resurgence of whooping cough to the wide use of acellular pertussis vaccines (aPs) as components of combination products. In this regard, WHO encourages countries that have not yet switched to the use of aPs to continue to use whole-cell pertussis vaccines (wPs) for primary vaccination. The experience of using pertussis vaccines has shown that companies do not always produce highly efficacious products. The use of statistical methods of samples quality control helps to ensure consistency of the technological process, which results in the production of more homogeneous products, and rules out the possibility of producing low-quality products. This paper presents the results of retrospective evaluation of the consistency of the wP (as a pertussis component of the DTP vaccine) production using Shewhart control charts. It was shown that at some points in time during the analyzed period from January 2017 until March 2018 the technological process of the company lacked proper statistical control. This increased the risk of producing non-uniform and defective products. In order to improve the quality and consistency of pertussis component batches, the company’s quality control and quality assurance services should make extensive use of Shewhart charts on a real-time basis.