Factors affecting vaccine handling and storage practices among immunization service providers in Ibadan, Oyo State, Nigeria.

Background: Improper handling has been identified as one of the major reasons for the decline in vaccine potency at the time of administration. Loss of potency becomes evident when immunised individuals contract the diseases the vaccines were meant to prevent. Objective: Assessing the factors associated with vaccine handling and storage practices. Methods: This was a cross-sectional study. Three-stage sampling was used to recruit 380 vaccine handlers from 273 health facilities from 11 Local Government areas in Ibadan. Data was analysed using SPSS version 16 Results: Seventy-three percent were aware of vaccine handling and storage guidelines with 68.4% having ever read such guidelines. Only 15.3% read a guideline less than 1 month prior to the study. About 65.0% had received training on vaccine management. Incorrect handling practices reported included storing injections with vaccines (13.7%) and maintaining vaccine temperature using ice blocks (7.6%). About 43.0% had good knowledge of vaccine management, while 66.1% had good vaccine management practices. Respondents who had good knowledge of vaccine handling and storage [OR=10.0, 95%CI (5.28 – 18.94), p < 0.001] and had received formal training on vaccine management [OR=5.3, 95%CI (2.50 – 11.14), p< 0.001] were more likely to have good vaccine handling and storage practices. Conclusion: Regular training is recommended to enhance vaccine handling and storage practices.

A Feminist Affective Turn for Public Relations: Mothers, Passionate Publics, and the Childhood Vaccine Debate

This project proposes a feminist intervention in how affect and publics are theorized in public relations research. Drawing from extant literature, I argue that public relations theories of affect and publics have been apolitical and lack depth and context (Leitch & Motion, 2010a). Using the context of the online childhood vaccine debate, I illustrate several theories and concepts of the new feminist affective turn, as well as postmodern theories of affect, relevant to public relations research: (a) Public Feelings, “ugly” feelings, agency, and community (Cvetkovich, 2012; Ngai, 2007); (b) passionate politics (Mouffe, 2014); (c) postmodern assemblages, biopower, and body politics (Deleuze & Guattari, 1988; Foucault, 1984); (d) affective facts and logics of future threats (Massumi, 2010); and (e) affective ethics (Bertleson & Murphie, 2010). Scholarship in the areas of public relations, risk, feminist and postmodern affect theory, and the vaccine debate provided theoretical grounding for this project. My research questions asked: How is feminist affect theory embodied by mothers in the vaccine debate? How do mothers understand risks as affective facts in the vaccine debate (if at all)? What affective logics are used by mothers in the vaccine debate (if any)? And, What are sources of knowledge for mothers in the vaccine debate? Multi-sited online ethnographic methods were used to explore how feminist affect theory contributes to public relations research, including 29 one-on-one in-depth interviews with mothers of young children and participant observation of 15 online discussions about vaccines on parenting websites BabyCenter.com, TheBump.com, and WhatToExpect.com. I used snowball sampling to recruit interview participants and grounded theory (Glaser & Strauss, 1967) to analyze interview and online data. Results show that feminist affect theory contributes to theoretical and practical knowledge in public relations by politicizing and contextualizing understandings of publics and elucidating how affective facts and logics inform publics’ knowledge and choices, specifically in the context of risk. I also found evidence of suppression of dissent (Martin, 2015) and academic bias in vaccine debate research, which resulted in cultures of silence. Further areas of study included how specific contexts such as motherhood and issues of privilege and access affect publics’ experiences, knowledges, and choices.

Co-administration of plasmid-encoded granulocyte-macrophage colony-stimulating factor increases human immunodeficiency virus-1 DNA vaccine-induced polyfunctional CD4+ T-cell responses

T-cell based vaccines against human immunodeficiency virus (HIV) generate specific responses that may limit both transmission and disease progression by controlling viral load. Broad, polyfunctional, and cytotoxic CD4+ T-cell responses have been associated with control of simian immunodeficiency virus/HIV-1 replication, supporting the inclusion of CD4+ T-cell epitopes in vaccine formulations. Plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) co-administration has been shown to induce potent CD4+ T-cell responses and to promote accelerated priming and increased migration of antigen-specific CD4+ T-cells. However, no study has shown whether co-immunisation with pGM-CSF enhances the number of vaccine-induced polyfunctional CD4+ T-cells. Our group has previously developed a DNA vaccine encoding conserved, multiple human leukocyte antigen (HLA)-DR binding HIV-1 subtype B peptides, which elicited broad, polyfunctional and long-lived CD4+ T-cell responses. Here, we show that pGM-CSF co-immunisation improved both magnitude and quality of vaccine-induced T-cell responses, particularly by increasing proliferating CD4+ T-cells that produce simultaneously interferon-γ, tumour necrosis factor-α and interleukin-2. Thus, we believe that the use of pGM-CSF may be helpful for vaccine strategies focused on the activation of anti-HIV CD4+ T-cell immunity.

The mc2-CMX vaccine induces an enhanced immune response against Mycobacterium tuberculosis compared to Bacillus Calmette-Guérin but with similar lung inflammatory effects

Although the attenuated Mycobacterium bovis Bacillus Calmette-Guérin (BCG) vaccine has been used since 1921, tuberculosis (TB) control still proceeds at a slow pace. The main reason is the variable efficacy of BCG protection against TB among adults, which ranges from 0-80%. Subsequently, the mc2-CMX vaccine was developed with promising results. Nonetheless, this recombinant vaccine needs to be compared to the standard BCG vaccine. The objective of this study was to evaluate the immune response induced by mc2-CMX and compare it to the response generated by BCG. BALB/c mice were immunised with both vaccines and challenged with Mycobacterium tuberculosis (Mtb). The immune and inflammatory responses were evaluated by ELISA, flow cytometry, and histopathology. Mice vaccinated with mc2-CMX and challenged with Mtb induced an increase in the IgG1 and IgG2 levels against CMX as well as recalled specific CD4+ T-cells that produced T-helper 1 cytokines in the lungs and spleen compared with BCG vaccinated and challenged mice. Both vaccines reduced the lung inflammatory pathology induced by the Mtb infection. The mc2-CMX vaccine induces a humoral and cellular response that is superior to BCG and is efficiently recalled after challenge with Mtb, although both vaccines induced similar inflammatory reductions.

Original Research Article Humoral and cellular immune responses to modified hepatitis B plasmid DNA vaccine in mice

Purpose: To evaluate the immunogenicity and types of immune response of a quality-controlled modified recombinant hepatitis B surface antigen (HBsAg) plasmid encoding HBsAg in mice. Methods: The characterized plasmid DNA was used in the immunization of Balb/c mice. Three groups of mice were intramuscularly injected with three different concentrations (50, 25 and 10 μg/100 μL) of the modified plasmid. Humoral immune response was monitored by enzyme-linked immunosorbent assay (ELISA), while cellular immune response was investigated by analysis of spleen cytokine profile (TNFα, IFN γ and IL2) as well as CD69 expression level in CD4 and CD8 positive cells. Results: In general, the activated CD4 cells showing intracellular cytokines were higher than CD8 positive population of cells (p < 0.05). These findings indicate that the vaccine induced both a humoral and cellular immunity. Cytokine profile also showed high levels of TNFα, IFN γ and IL2 and CD69 expression in the group of animals immunized at a dose of 10 μg when compared to control group (p < 0.05). Conclusion: A 10 μg dose intramuscular injection of the modified DNA-based vaccine encoding HBsAg in mice induces both high humoral and cellular immune responses.

Protein expression of Myt272-3 recombinant clone and in silico prediction of a possible vaccine candidate against Mycobacterium tuberculosis

Purpose: To investigate the expression of Myt272-3 recombinant protein and also to predict a possible protein vaccine candidate against Mycobacterium tuberculosis . Methods: Myt272-3 protein was expressed in pET30a+-Myt272-3 clone. The purity of the protein was determined using Dynabeads® His-Tag Isolation & Pulldown. Protein sequence was analysed in silico using bioinformatics software for the prediction of allergenicity, antigenicity, MHC-I and MHC-II binding, and B-cell epitope binding. Results: The candidate protein was a non-allergen with 15.19 % positive predictive value. It was also predicted to be antigenic, with binding affinity to MHC-I and MHC-II, as well as B-cell epitope binding. Conclusion: The predicted results obtained in this study provide a guide for practical design of a new tuberculosis vaccine.

Assessment of an oral Mycobacterium bovis BCG vaccine and an inactivated M. bovis preparation for wild boar in terms of adverse reactions, vaccine strain survival, and uptake by nontarget species

Wildlife vaccination is increasingly being considered as an option for tuberculosis control. We combined data from laboratory trials and an ongoing field trial to assess the risk of an oral Mycobacterium bovis BCG vaccine and a prototype heat-inactivated Mycobacterium bovis preparation for Eurasian wild boar (Sus scrofa). We studied adverse reactions, BCG survival, BCG excretion, and bait uptake by nontarget species. No adverse reactions were observed after administration of BCG (n = 27) or inactivated M. bovis (n = 21). BCG was not found at necropsy (175 to 300 days postvaccination [n = 27]). No BCG excretion was detected in fecal samples (n = 162) or in urine or nasal, oral, or fecal swab samples at 258 days postvaccination (n = 29). In the field, we found no evidence of loss of BCG viability in baits collected after 36 h (temperature range, 11°C to 41°C). Camera trapping showed that wild boar (39%) and birds (56%) were the most frequent visitors to bait stations (selective feeders). Wild boar activity patterns were nocturnal, while diurnal activities were recorded for all bird species. We found large proportions of chewed capsules (29%) (likely ingestion of the vaccine) and lost baits (39%) (presumably consumed), and the proportion of chewed capsules showed a positive correlation with the presence of wild boar. Both results suggest proper bait consumption (68%). These results indicate that BCG vaccination in wild boar is safe and that, while bait consumption by other species is possible, this can be minimized by using selective cages and strict timing of bait deployment.

Characterization of protection afforded by a bivalent virus-like particle vaccine against bluetongue virus serotypes 1 and 4 in sheep

BACKGROUND Bluetongue virus (BTV) is an economically important, arthropod borne, emerging pathogen in Europe, causing disease mainly in sheep and cattle. Routine vaccination for bluetongue would require the ability to distinguish between vaccinated and infected individuals (DIVA). Current vaccines are effective but are not DIVA. Virus-like particles (VLPs) are highly immunogenic structural mimics of virus particles, that only contain a subset of the proteins present in a natural infection. VLPs therefore offer the potential for the development of DIVA compatible bluetongue vaccines. METHODOLOGY/PRINCIPAL FINDINGS Merino sheep were vaccinated with either monovalent BTV-1 VLPs or a bivalent mixture of BTV-1 VLPs and BTV-4 VLPs, and challenged with virulent BTV-1 or BTV-4. Animals were monitored for clinical signs, antibody responses, and viral RNA. 19/20 animals vaccinated with BTV-1 VLPs either alone or in combination with BTV-4 VLPs developed neutralizing antibodies to BTV-1, and group specific antibodies to BTV VP7. The one animal that showed no detectable neutralizing antibodies, or group specific antibodies, had detectable viral RNA following challenge but did not display any clinical signs on challenge with virulent BTV-1. In contrast, all control animals' demonstrated classical clinical signs for bluetongue on challenge with the same virus. Six animals were vaccinated with bivalent vaccine and challenged with virulent BTV-4, two of these animals had detectable viral levels of viral RNA, and one of these showed clinical signs consistent with BTV infection and died. CONCLUSIONS There is good evidence that BTV-1 VLPs delivered as monovalent or bivalent immunogen protect from bluetongue disease on challenge with virulent BTV-1. However, it is possible that there is some interference in protective response for BTV-4 in the bivalent BTV-1 and BTV-4 VLP vaccine. This raises the question of whether all combinations of bivalent BTV vaccines are possible, or if immunodominance of particular serotypes could interfere with vaccine efficacy.

Characterization of the immune response induced by a commercially available inactivated bluetongue virus serotype 1 vaccine in sheep

The protective immune response generated by a commercial monovalent inactivated vaccine against bluetongue virus serotype 1 (BTV1) was studied. Five sheep were vaccinated, boost-vaccinated, and then challenged against BTV1 ALG/2006. RT-PCR did not detect viremia at any time during the experiment. Except a temperature increase observed after the initial and boost vaccinations, no clinical signs or lesions were observed. A specific and protective antibody response checked by ELISA was induced after vaccination and boost vaccination. This specific antibody response was associated with a significant increase in B lymphocytes confirmed by flow cytometry, while significant increases were not observed in T lymphocyte subpopulations (CD4(+), CD8(+), and WC1(+)), CD25(+) regulatory cells, or CD14(+) monocytes. After challenge with BTV1, the antibody response was much higher than during the boost vaccination period, and it was associated with a significant increase in B lymphocytes, CD14(+) monocytes, CD25(+) regulatory cells, and CD8(+) cytotoxic T lymphocytes.

Complications of pneumococcal bacteremia after 13-valent conjugate vaccine withdrawal

In the Region of Madrid, universal immunization with the 13-serotypes pneumococcal conjugate vaccine (PCV13) started in May 2010. In July 2012, public funding ceased. Vaccination coverage decreased from >95% to 82% in 2013 and to 67% in 2014. Our aim was to investigate the impact of PCV13 withdrawal from Madrid Region's universal immunization program on the incidence of complicated pneumococcal bacteremia. We performed a multi-center retrospective cohort study, from 2009 to 2014. Participants were children aged <14 years with Streptococcus pneumoniae bacteremia. Complications were defined as any condition requiring intensive care or surgery. Sequelae were conditions lasting ≥90 days. A total of 168 patients were recruited. One-fourth of both immunized and non-immunized patients had complications. Global complications increased after PCV13 withdrawal. A total of 28% of PCV13 serotypes presented complications. Complications due to PCV13 serotypes did not increase after July 2012. No-PCV13 serotypes increased progressively from 2009 on, and 23% presented complications. A significant risk of complications was found for patients with meningitis, empyema, C-reactive protein >100 mg/L, and serotype 1. A multivariate analysis indicated that complications were associated with meningitis and hospital admission after July 2012. Sequelae were significantly associated with children <2 years of age, meningitis and no-PCV13 serotypes. The incidence of complications due to PCV13 serotypes did not increase two years after PCV13 withdrawal. Nevertheless, all-serotypes complications increased. The likely cause was that no-PCV13 serotypes (associated with meningitis) are on the rise.

Towards in silico IBV vaccine design: defining the role of polymorphism in viral attenuation

The gammacoronavirus, Infectious Bronchitis Virus (IBV), is a respiratory pathogen of chickens. IBV is a constant threat to poultry production as established vaccines are often ineffective against emerging strains. This requires constant and rapid vaccine production by a process of viral attenuation by egg passage, but the essential forces leading to attenuation in the virus have not yet been characterised. Knowledge of these factors will lead to the development of more effective, rationally attenuated, live vaccines and reduction of the mortality and morbidity caused by this pathogen. M41 CK strain was egg passaged four times many years ago at Houghton Poultry Research Station and stored as M41-CK EP4 (stock virus at The Pirbright Institute since 1992). It was the first egg passage to have its genome pyrosequenced and was therefore used as the baseline reference. The overall aim of this project was to analyse deep sequence data obtained from four IBV isolates (called A, A1, C and D) each originating from the common M41-CK EP4 (ep4) and independently passaged multiple times in embryonated chicken eggs (figure 1.1). Highly polymorphic encoding regions of the IBV genome were then identified which are likely involved in the attenuation process through the formation of independent SNPs and/or SNP clusters. This was then used to direct targeted investigation of SNPs during the attenuation process of the four IBV passages. A previously generated deep sequence dataset was used as a preliminary map of attenuation for one virulent strain of IBV. This investigation showed the nucleocapsid and spike as two highly polymorphic encoding regions within the IBV genome with the highest proportion of SNPs compared to encoding region size. This analysis then led to more focussed studies of the nucleocapsid and spike encoding region with the ultimate aim of mapping key attenuating regions and nucleotide positions. The 454 pyrosequencing data and further investigation of nucleocapsid and spike encoding regions have identified the SNPs present at the same nucleotide positions within analysed A, A1, C and D isolates. These SNPs probably play a crucial role in viral attenuation and universal vaccine production but it is not clear if independent SNPs are also involved in loss of virulence. The majority of SNPs accumulated at different nucleotide positions without further continuation in Sanger sequenced egg passages presenting S2 subunit (spike) and nucleocapsid as polymorphic encoding regions which in nature remain highly conserved.

Design of the ATAQ peptide and its evaluation as an immunogen to develop a Rhipicephalus vaccine

2016

A cluster-randomised intervention trial against Schistosoma japonicum in the Peoples' Republic of China: bovine and human transmission

Background Zoonotic schistosomiasis japonica is a major public health problem in China. Bovines, particularly water buffaloes, are thought to play a major role in the transmission of schistosomiasis to humans in China. Preliminary results (1998–2003) of a praziquantel (PZQ)-based pilot intervention study we undertook provided proof of principle that water buffaloes are major reservoir hosts for S. japonicum in the Poyang Lake region, Jiangxi Province. Methods and Findings Here we present the results of a cluster-randomised intervention trial (2004–2007) undertaken in Hunan and Jiangxi Provinces, with increased power and more general applicability to the lake and marshlands regions of southern China. The trial involved four matched pairs of villages with one village within each pair randomly selected as a control (human PZQ treatment only), leaving the other as the intervention (human and bovine PZQ treatment). A sentinel cohort of people to be monitored for new infections for the duration of the study was selected from each village. Results showed that combined human and bovine chemotherapy with PZQ had a greater effect on human incidence than human PZQ treatment alone. Conclusions The results from this study, supported by previous experimental evidence, confirms that bovines are the major reservoir host of human schistosomiasis in the lake and marshland regions of southern China, and reinforce the rationale for the development and deployment of a transmission blocking anti-S. japonicum vaccine targeting bovines.

Paramedic knowledge of infectious disease aetiology and transmission in an Australian Emergency Medical System

Introduction: Paramedics and other emergency health workers are exposed to infectious disease particularly when undertaking exposure-prone procedures as a component of their everyday practice. This study examined paramedic knowledge of infectious disease aetiology and transmission in the pre-hospital care environment.--------- Methods: A mail survey of paramedics from an Australian ambulance service (n=2274) was conducted.--------- Results: With a response rate of 55.3% (1258/2274), the study demonstrated that paramedic knowledge of infectious disease aetiology and modes of transmission was poor. Of the 25 infectious diseases included in the survey, only three aetiological agents were correctly identified by at least 80% of respondents. The most accurate responses for aetiology of individual infectious diseases were for HIV/AIDS (91.4%), influenza (87.4%), and hepatitis B (85.7%). Poorest results were observed for pertussis, infectious mononucleosis, leprosy, dengue fever, Japanese B encephalitis and vancomycin resistant enterococcus (VRE), all with less than half the sample providing a correct response. Modes of transmission of significant infectious diseases were also assessed. Most accurate responses were found for HIV/AIDS (85.8%), salmonella (81.9%) and influenza (80.1%). Poorest results were observed for infectious mononucleosis, diphtheria, shigella, Japanese B encephalitis, vancomycin resistant enterococcus, meningococcal meningitis, rubella and infectious mononucleosis, with less than a third of the sample providing a correct response.--------- Conclusions: Results suggest that knowledge of aetiology and transmission of infectious disease is generally poor amongst paramedics. A comprehensive in-service education infection control programs for paramedics with emphasis on infectious disease aetiology and transmission is recommended.

CTA1-DD is an effective adjuvant for targeting anti-chlamydial immunity to the murine genital mucosa

Chlamydia trachomatis is a significant human pathogen with potentially severe disease sequelae in the genital tract, including infertility. A successful vaccine will need to effectively target immunity to the genital mucosa. Intranasal immunisation with cholera toxin (CT) can target immunity to the genital tract, but has the potential to cause neurological side effects. CTA1-DD is a non-toxic potent mucosal adjuvant which combines the enzymatic properties of CT, with a B cell targeting moiety. Here, we demonstrate that intranasal immunisation with CTA1-DD and chlamydial Major Outer Membrane Protein (MOMP) results in the induction of neutralising systemic and mucosal antibodies, and reduces the level of chlamydial shedding following intravaginal challenge with Chlamydia muridarum. Thus, CTA1-DD is an effective adjuvant for vaccine development against Chlamydia trachomatis, and possibly also a range of other genital pathogens.