Displaying publications 41 - 60 of 89 in total

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  1. Mariappan V, Vellasamy KM, Thimma JS, Hashim OH, Vadivelu J
    Vaccine, 2010 Feb 3;28(5):1318-24.
    PMID: 19944788 DOI: 10.1016/j.vaccine.2009.11.027
    Burkholderia cepacia is an opportunistic human pathogen associated with lung infections. Secretory proteins of B. cepacia are known to be involved in virulence and may mediate important host-pathogen interactions. In the present study, secretory proteins isolated from B. cepacia culture supernatant were separated using two-dimensional gel electrophoresis, followed by Western blot analysis to identify the immunogenic proteins. Mice antibodies raised to B. cepacia inactivated whole bacteria, outer membrane protein and culture filtrate antigen detected 74, 104 and 32 immunogenic proteins, respectively. Eighteen of these immunogenic proteins which reacted with all three antibodies were identified and might be potential molecules as a diagnostic marker or a putative candidate vaccine against B. cepacia infections.
  2. Coleman PG, Dye C
    Vaccine, 1996 Feb;14(3):185-6.
    PMID: 8920697
    WHO recommends that 70% of dogs in a population should be immunized to eliminate or prevent outbreaks of rabies. This critical percentage (pc) has been established empirically from observations on the relationship between vaccination coverage and rabies incidence in dog populations around the world. Here, by contrast, we estimate pc by using epidemic theory, together with data available from four outbreaks in urban and rural areas of the USA, Mexico, Malaysia and Indonesia. From the rate of increase of cases at the beginning of these epidemics, we obtain estimates of the basic case reproduction number of infection, R0, in the range 1.62-2.33, implying that pc lies between 39% and 57%. The errors attached to these estimates of pc suggest that the recommended coverage of 70% would prevent a major outbreak of rabies on no fewer than 96.5% of occasions.
  3. Su YC, Wan KL, Mohamed R, Nathan S
    Vaccine, 2010 Jul 12;28(31):5005-11.
    PMID: 20546831 DOI: 10.1016/j.vaccine.2010.05.022
    Burkholderia pseudomallei is resistant to a wide range of antibiotics, leading to relapse and recrudescence of melioidosis after cessation of antibiotic therapy. More effective immunotherapies are needed for better management of melioidosis. We evaluated the prophylactic potential of the immunogenic outer membrane protein Omp85 as a vaccine against murine melioidosis. Immunization of BALB/c mice with recombinant Omp85 (rOmp85) triggered a Th2-type immune response. Up to 70% of the immunized animals were protected against infectious challenge of B. pseudomallei with reduced bacterial load in extrapulmonary organs. Mouse anti-rOmp85 promoted complement-mediated killing and opsonophagocytosis of B. pseudomallei by human polymorphonuclear cells. In conclusion, we demonstrated that B. pseudomallei Omp85 is potentially able to induce protective immunity against melioidosis.
  4. Lim PY, Hickey AC, Jamiluddin MF, Hamid S, Kramer J, Santos R, et al.
    Vaccine, 2015 Nov 4;33(44):6017-24.
    PMID: 26271825 DOI: 10.1016/j.vaccine.2015.05.108
    A vaccine against human enterovirus 71 (EV-A71) is urgently needed to combat outbreaks of EV-A71 and in particular, the serious neurological complications that manifest during these outbreaks. In this study, an EV-A71 virus-like-particle (VLP) based on a B5 subgenogroup (EV-A71-B5 VLP) was generated using an insect cell/baculovirus platform. Biochemical analysis demonstrated that the purified VLP had a highly native procapsid structure and initial studies in vivo demonstrated that the VLPs were immunogenic in mice. The impact of VLP immunization on infection was examined in non-human primates using a VLP prime-boost strategy prior to EV-A71 challenge. Rhesus macaques were immunized on day 0 and day 21 with VLPs (100 μg/dose) containing adjuvant or with adjuvant alone (controls), and were challenged with EV-A71 on day 42. Complete blood counts, serum chemistry, magnetic resonance imaging (MRI) scans, and histopathology results were mostly normal in vaccinated and control animals after virus challenge demonstrating that the fatal EV-A71-B3 clinical isolate used in this study was not highly virulent in rhesus macaques. Viral genome and/or infectious virus were detected in blood, spleen or brain of two of three control animals, but not in any specimens from the vaccinated animals, indicating that VLP immunization prevented systemic spread of EV-A71 in rhesus macaques. High levels of IgM and IgG were detected in VLP-vaccinated animals and these responses were highly specific for EV-A71 particles and capsid proteins. Serum from vaccinated animals also exhibited similar neutralizing activity against different subgenogroups of EV-A71 demonstrating that the VLPs induced cross-neutralizing antibodies. In conclusion, our EV-A71-B5 VLP is safe, highly immunogenic, and prevents systemic EV-A71-B3 infection in nonhuman primates making it a viable attractive vaccine candidate for EV-A71.
  5. Neuhann JM, Stemler J, Carcas AJ, Frías-Iniesta J, Akova M, Bethe U, et al.
    Vaccine, 2023 Nov 22;41(48):7166-7175.
    PMID: 37919141 DOI: 10.1016/j.vaccine.2023.10.029
    BACKGROUND: Vaccination remains crucial for protection against severe SARS-CoV-2 infection, especially for people of advanced age, however, optimal dosing regimens are as yet lacking.

    METHODS: EU-COVAT-1-AGED Part A is a randomised controlled, adaptive, multicentre phase II trial evaluating safety and immunogenicity of a 3rd vaccination (1st booster) in individuals ≥75 years. Fifty-three participants were randomised to full-doses of either mRNA-1273 (Spikevax®, 100 µg) or BNT162b2 (Comirnaty®, 30 µg). The primary endpoint was the rate of 2-fold circulating antibody titre increase 14 days post-vaccination measured by quantitative electrochemiluminescence (ECL) immunoassay, targeting RBD region of Wuhan wild-type SARS-CoV-2. Secondary endpoints included the changes in neutralising capacity against wild-type and 25 variants of concern at 14 days and up to 12 months. Safety was assessed by monitoring of solicited adverse events (AEs) for seven days after on-study vaccination. Unsolicited AEs were collected until the end of follow-up at 12 months, SAEs were pursued for a further 30 days.

    RESULTS: Between 08th of November 2021 and 04th of January 2022, 53 participants ≥75 years received a COVID-19 vaccine as 1st booster. Fifty subjects (BNT162b2 n = 25/mRNA-1273 n = 25) were included in the analyses for immunogenicity at day 14. The primary endpoint of a 2-fold anti-RBD IgG titre increase 14 days after vaccination was reached for all subjects. A 3rd vaccination of full-dose mRNA-1273 provided higher anti-RBD IgG titres (Geometric mean titre) D14 mRNA-127310711 IU/mL (95 %-CI: 8003;14336) vs. BNT162b2: 7090 IU/mL (95 %-CI: 5688;8837). We detected a pattern showing higher neutralising capacity of full-dose mRNA-1273 against wild-type as well as for 23 out of 25 tested variants.

    INTERPRETATION: Third doses of either BNT162b2 or mRNA-1273 provide substantial circulating antibody increase 14 days after vaccination. Full-dose mRNA-1273 provides higher antibody levels with an overall similar safety profile for people ≥75 years.

    FUNDING: This trial was funded by the European Commission (Framework Program HORIZON 2020).

    Matched MeSH terms: Immunogenicity, Vaccine
  6. Künzi V, Klap JM, Seiberling MK, Herzog C, Hartmann K, Kürsteiner O, et al.
    Vaccine, 2009 Jun 2;27(27):3561-7.
    PMID: 19464535 DOI: 10.1016/j.vaccine.2009.03.062
    Despite the established benefit of intramuscular (i.m.) influenza vaccination, new adjuvants and delivery methods for comparable or improved immunogenicity are being explored. Intradermal (i.d.) antigen administration is hypothesized to initiate an efficient immune response at reduced antigen doses similar to that observed after i.m. full dose vaccination.
  7. Souza AR, Braga JA, de Paiva TM, Loggetto SR, Azevedo RS, Weckx LY
    Vaccine, 2010 Jan 22;28(4):1117-20.
    PMID: 20116631 DOI: 10.1016/j.vaccine.2009.05.046
    The immunogenicity and tolerability of virosome and of split influenza vaccines in patients with sickle cell anemia (SS) were evaluated. Ninety SS patients from 8 to 34 years old were randomly assigned to receive either virosome (n=43) or split vaccine (n=47). Two blood samples were collected, one before and one 4-6 weeks after vaccination. Antibodies against viral strains (2006) A/New Caledonia (H1N1), A/California (H3N2), B/Malaysia were determined using the hemagglutinin inhibition test. Post-vaccine reactions were recorded over 7 days. Seroconversion rates for H1N1, H3N2 and B were 65.1%, 60.4% and 83.7% for virosome vaccine, and 68.0%, 61.7% and 68.0% for split vaccine. Seroprotection rates for H1N1, H3N2 e B were 100%, 97.6% and 69.7% for virosome, and 97.8%, 97.8% and 76.6% for split vaccine. No severe adverse reactions were recorded. Virosome and split vaccines in patients with sickle cell anemia were equally immunogenic, with high seroconversion and seroprotection rates. Both vaccines were well tolerated.
  8. Rapeah S, Norazmi MN
    Vaccine, 2006 Apr 24;24(17):3646-53.
    PMID: 16494975 DOI: 10.1016/j.vaccine.2006.01.053
    Recombinant Mycobacterium bovis bacille Calmette-Guèrin (rBCG) expressing the malarial epitopes F2R(II)EBA and (NANP)3 as well as two T cell epitopes of the M. tuberculosis ESAT-6 antigen, generated in favour of mycobacterium codon usage elicited specific immune response against these epitopes. Immunised Balb/c mice demonstrated an increase in almost all of the IgG subclasses against both malarial epitopes and enhanced splenocyte proliferative response against the malarial epitopes as well as selected peptides of ESAT-6. Furthermore, flow cytometric analyses showed elevated numbers of CD4+ lymphocytes expressing IFN-gamma and IL-2 against the ESAT-6 peptides, suggesting a specific Th1-mediated response. This study demonstrated that expressing malarial and TB epitopes in a single rBCG construct induced appropriate humoral and cellular immune response against immunogenic epitopes from both organisms.
    Matched MeSH terms: BCG Vaccine/immunology*
  9. Cohen C, Moreira ED, Nañez H, Nachiappan JP, Arvinder-Singh HS, Huoi C, et al.
    Vaccine, 2019 03 22;37(13):1868-1875.
    PMID: 30826144 DOI: 10.1016/j.vaccine.2019.01.087
    BACKGROUND: The background incidence of viscerotropic- (VLD) and neurotropic-like disease (NLD) unrelated to immunization in dengue-endemic countries is currently unknown.

    METHODS: This retrospective population-based analysis estimated crude and standardized incidences of VLD and NLD in twelve hospitals in Brazil (n = 3), Mexico (n = 3), and Malaysia (n = 6) over a 1-year period before the introduction of the tetravalent dengue vaccine. Catchment areas were estimated using publicly available population census information and administrative data. The denominator population for incidence rates was calculated, and sensitivity analyses assessed the impact of important assumptions.

    RESULTS: Total cases adjudicated as definite VLD were 5, 57, and 56 in Brazil, Mexico, and Malaysia, respectively. Total cases adjudicated as definite NLD were 103, 29, and 26 in Brazil, Mexico, and Malaysia, respectively. Crude incidence rates of cases adjudicated as definite VLD in Brazil, Mexico, and Malaysia were 1.17, 2.60, and 1.48 per 100,000 person-years, respectively. Crude incidence rates of cases adjudicated as definite NLD in Brazil, Mexico, and Malaysia were 4.45, 1.32, and 0.69 per 100,000 person-years, respectively.

    CONCLUSIONS: Background incidence estimates of VLD and NLD obtained in Mexico, Brazil, and Malaysia could provide context for cases occurring after the introduction of the tetravalent dengue vaccine.

  10. Vaccine, 2006 Nov 10;24(44-46):6791-2.
    PMID: 17167887
    ESWI recommends that the 25 European Union nations strive to vaccinate one-third of their collective population every year by 2010. This translates into an annual vaccine usage of 150 million doses for a population of 455 million. However, the current vaccine usage in Europe is 79 million doses, meaning that only 40% of ESWI's recommended target population is being vaccinated in the EU-25. Indeed, the EU's current risk groups equal about 28% of its population, but it is estimated that less than 62% are being vaccinated with the current vaccine supply--the equivalent of 17% of the total population. Clearly, as ESWI noted in its concluding position paper at the Malta conference, "a large proportion of those traditionally assumed to be at most risk from influenza are not being vaccinated." How to change this and minimize the consequences of a pandemic? "It's very interesting how the arithmetic works, given the goal of immunizing 75 percent of Europe's high-risk group, " said Dr K.Nichol of the University of Minnesota Medical Center who chaired the session. "If you go from a trivalent vaccine to a monovalent one, then you triple the number of doses you can manufacture. Thus, you could produce enough doses for the entire population of the EU." However, there is no coordinated approach in Europe, meaning such an optimistic scenario is unlikely in the medium-term. For the time being, emphasis must be on raising public awareness and raising vaccination rates at the local level, starting with health care workers themselves. Here the role and attitude of health policy officials and--critically--health care workers are crucial. These front-line policy and healthcare professionals constitute both the problem and the solution to a more effective influenza vaccine effort in Europe: they know first-hand the institutional obstacles blocking progress--i.e., lack of resources, poorly focused public information campaigns, etc.--but their own work practices and attitudes can be misdirected, too. To identify the issues and help the participants produce a set of recommendations, ESWI brought in Penny Lawson from to facilitate Dr.K. Nichol to steer this session's workshop debate. The participants were a diverse group of 35 health care workers from Australia, Finland, France, Germany, Malaysia, Malta, Netherlands, Norway, Poland, Portugal, Spain, Sweden and the UK.
  11. Cowling BJ, Caini S, Chotpitayasunondh T, Djauzi S, Gatchalian SR, Huang QS, et al.
    Vaccine, 2017 Feb 07;35(6):856-864.
    PMID: 28081970 DOI: 10.1016/j.vaccine.2016.12.064
    The fourth roundtable meeting of the Global Influenza Initiative (GII) was held in Hong Kong, China, in July 2015. An objective of this meeting was to gain a broader understanding of the epidemiology, surveillance, vaccination policies and programs, and obstacles to vaccination of influenza in the Asia-Pacific region through presentations of data from Australia, Hong Kong, India, Indonesia, Malaysia, New Zealand, the Philippines, Taiwan, Thailand, and Vietnam. As well as a need for improved levels of surveillance in some areas, a range of factors were identified that act as barriers to vaccination in some countries, including differences in climate and geography, logistical challenges, funding, lack of vaccine awareness and education, safety concerns, perceived lack of vaccine effectiveness, and lack of inclusion in national guidelines. From the presentations at the meeting, the GII discussed a number of recommendations for easing the burden of influenza and overcoming the current challenges in the Asia-Pacific region. These recommendations encompass the need to improve surveillance and availability of epidemiological data; the development and publication of national guidelines, where not currently available and/or that are in line with those proposed by the World Health Organization; the requirement for optimal timing of vaccination programs according to local or country-specific epidemiology; and calls for advocacy and government support of vaccination programs in order to improve availability and uptake and coverage. In conclusion, in addition to the varied epidemiology of seasonal influenza across this diverse region, there are a number of logistical and resourcing issues that present a challenge to the development of optimally effective vaccination strategies and that need to be overcome to improve access to and uptake of seasonal influenza vaccines. The GII has developed a number of recommendations to address these challenges and improve the control of influenza.
  12. Lum LC, Borja-Tabora CF, Breiman RF, Vesikari T, Sablan BP, Chay OM, et al.
    Vaccine, 2010 Feb 10;28(6):1566-74.
    PMID: 20003918 DOI: 10.1016/j.vaccine.2009.11.054
    Children aged 11 to <24 months received 2 intranasal doses of live attenuated influenza vaccine (LAIV) or placebo, 35+/-7 days apart. Dose 1 was administered concomitantly with a combined measles, mumps, and rubella vaccine (Priorix). Seroresponses to measles and mumps were similar between groups. Compared with placebo, response rates to rubella in LAIV+Priorix recipients were statistically lower at a 15 IU/mL threshold (83.9% vs 78.0%) and the prespecified noninferiority criteria were not met. In a post hoc analysis using an alternate widely accepted threshold of 10 IU/mL, the noninferiority criteria were met (93.4% vs 89.8%). Concomitant administration with Priorix did not affect the overall influenza protection rate of LAIV (78.4% and 63.8% against antigenically similar influenza strains and any strain, respectively).
    Matched MeSH terms: Measles-Mumps-Rubella Vaccine/administration & dosage; Measles-Mumps-Rubella Vaccine/immunology*
  13. Tricarico S, McNeil HC, Head MG, Cleary DW, Clarke SC, MYCarriage
    Vaccine, 2017 04 25;35(18):2288-2290.
    PMID: 28347503 DOI: 10.1016/j.vaccine.2017.03.053
  14. Gladstone RA, Siira L, Brynildsrud OB, Vestrheim DF, Turner P, Clarke SC, et al.
    Vaccine, 2022 Feb 11;40(7):1054-1060.
    PMID: 34996643 DOI: 10.1016/j.vaccine.2021.10.046
    BACKGROUND: Pneumococcal disease outbreaks of vaccine preventable serotype 4 sequence type (ST)801 in shipyards have been reported in several countries. We aimed to use genomics to establish any international links between them.

    METHODS: Sequence data from ST801-related outbreak isolates from Norway (n = 17), Finland (n = 11) and Northern Ireland (n = 2) were combined with invasive pneumococcal disease surveillance from the respective countries, and ST801-related genomes from an international collection (n = 41 of > 40,000), totalling 106 genomes. Raw data were mapped and recombination excluded before phylogenetic dating.

    RESULTS: Outbreak isolates were relatively diverse, with up to 100 SNPs (single nucleotide polymorphisms) and a common ancestor estimated around the year 2000. However, 19 Norwegian and Finnish isolates were nearly indistinguishable (0-2 SNPs) with the common ancestor dated around 2017.

    CONCLUSION: The total diversity of ST801 within the outbreaks could not be explained by recent transmission alone, suggesting that harsh environmental and associated living conditions reported in the shipyards may facilitate invasion of colonising pneumococci. However, near identical strains in the Norwegian and Finnish outbreaks does suggest that transmission between international shipyards also contributed to those outbreaks. This indicates the need for improved preventative measures in this working population including pneumococcal vaccination.

  15. Khan TM, Khan AU, Ali I, Wu DB
    Vaccine, 2016 Mar 8;34(11):1393-8.
    PMID: 26845740 DOI: 10.1016/j.vaccine.2016.01.045
    A cross-sectional study was carried out among HCPs in Northwest General Hospital & Research Centre, Hayatabad Peshawar, Pakistan. The purpose of this study was to investigate knowledge, awareness and attitude of HCPs towards influenza vaccination. A total of N=170 questionnaires were distributed among the staff. There was a 97% response rate to this survey (n=165). The median age of the respondents was 30 years and most of them, 98 (59.0%), were from age group of 24-30 years. The majority of the HCPs that participated in this study were male 106 (64.2%), and by profession, the majority were physicians 77 (46.7%), followed by pharmacists and nurses. A majority 114 (69.1%) believed that it was not compulsory for HCPs to get vaccinated for influenza. Top three identified barriers to vaccination were: not everyone is familiar with the availability of the influenza vaccination at their institution (Relative importance weight factors (RIWF)=0.71), due to needle fear I do not like to get vaccinated (RIWF=0.70) and it is not compulsory for healthcare professionals to get vaccinated for influenza (RIWF=0.64). The logistic regression analysis has revealed association for job experience and profession with the most of the eleven knowledge item. However, when overall sum of eleven items were tested to identify the factors affecting the knowledge score, along with profession (-0.215 [-0.389 to 0.040]; p=0.016) and job experience (0.823 [0.521-1.125]; p<0.001) HCPs age (-0.409 [-0.755 to -0.064]; p=0.020) was found to be another significant factor affecting the total knowledge score of HCPs. Overall, scoring of the correct responses revealed that nurses have better knowledge and understanding about influenza and the influenza vaccination (6.5±0.8, p<0.001*), followed by pharmacists (6.3±1.14) and physicians. In spite of the published guidelines and recommendations, a very low percentage of the healthcare professionals in our hospital were vaccinated against influenza, and the barriers to vaccination were prevalent. Various strategies, including arranging seminars regarding awareness about vaccinations, are required to improve the knowledge and overall outcomes.
  16. Chow SN, Soon R, Park JS, Pancharoen C, Qiao YL, Basu P, et al.
    Vaccine, 2010 May 14;28(22):3809-17.
    PMID: 20347631 DOI: 10.1016/j.vaccine.2010.03.027
    To determine why HPV vaccination uptake is low in Asia, we surveyed attitudes, knowledge and communication about cervical cancer and HPV vaccination amongst 480 physicians and 1617 randomly selected urban mothers who could afford HPV vaccines in Korea, Malaysia, Taiwan and Thailand. HPV vaccine rejection by mothers was linked with poor knowledge and low perceptions of self-relevance. Physicians' likelihood of raising the subject and/or recommending vaccination was linked to how proactively they advocate preventive health, their attitude to the subject's sensitivity and their knowledge levels. Because most Asian mothers seek doctors' advice and prefer them to take the initiative, physicians should be more proactive in discussing and recommending HPV vaccination.
  17. Basa JE, Clemens R, Clemens SAC, Nicholson M
    Vaccine, 2024 Apr 02;42(9):2326-2336.
    PMID: 38448324 DOI: 10.1016/j.vaccine.2024.02.047
    This study examined the performance and structures of national immunization program in five middle-income Southeast Asian countries - Malaysia, Thailand, Philippines, Viet Nam, and Myanmar, and analyzed how the different structures relate to the difference in program performance to identify effective strategies in the study countries that facilitated good immunization performance. Data were derived from published literature, and WHO/UNICEF/Gavi databases, with 2010 as the baseline year. UMICs Malaysia and Thailand maintained ≥90 % coverage from 2010 to 2020 and even during the COVID-19 pandemic in 2021. LMICs Viet Nam and donor-supported Myanmar also achieved 80-90 % coverage for most routine vaccines in 2020. The Philippines have not reached ≥90 % coverage since 2010, with the maximum only 72 % (MCV1 and Polio3) in 2020. All study countries prioritize immunization and increased government financing since 2010 by minimum 91 % in Malaysia and 1897 % in Myanmar. However, Myanmar still largely depended on donor support with government financing only 32 % of immunization costs in 2021. The Philippines funds 100 % of immunization costs and ensures sustainable financing for the NIP through earmarked "sin tax" revenues from alcohol and tobacco. Donor support influenced new vaccine introductions among the study countries, with Gavi countries Myanmar and Viet Nam introducing more new vaccines, compared to Gavi-ineligible Malaysia and Thailand. The Philippines reported vaccine stock-outs every year amounting to 28 stock-outs events from 2010 to 2019, compared to only 1-4 stockouts in the other study countries. Donor support, innovative financing, and domestic vaccine manufacturing all play an important role in the efficient delivery of immunization services as demonstrated by the several new vaccine introductions and high immunization rates in Myanmar though Gavi and UNICEF support, additional annual $1.2 billion budget for health and immunization from "sin taxes" in the Philippines, and lack of stockouts for vaccines sourced at affordable prices from domestic manufacturers in Viet Nam.
  18. Monath TP, Seligman SJ, Robertson JS, Guy B, Hayes EB, Condit RC, et al.
    Vaccine, 2015 Jan 01;33(1):62-72.
    PMID: 25446819 DOI: 10.1016/j.vaccine.2014.10.004
    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines.
  19. Shilling H, Murray G, Brotherton JML, Hawkes D, Saville M, Sivertsen T, et al.
    Vaccine, 2020 01 29;38(5):1186-1193.
    PMID: 31767467 DOI: 10.1016/j.vaccine.2019.11.019
    INTRODUCTION: Australia has recently implemented major changes in cervical cancer prevention policies including introduction of primary human papillomavirus (HPV) screening starting at age 25, and replacement of the quadrivalent HPV vaccine with the nonavalent vaccine in the national school-based program. We assessed the feasibility and utility of conducting HPV testing in residual clinical specimens submitted for routine Chlamydia trachomatis screening, as a means of tracking HPV vaccine program impact among young sexually active women.

    METHODS: De-identified residual specimens from women aged 16-24 years submitted for chlamydia testing were collected from three pathology laboratories in Victoria and New South Wales. Limited demographic information, and chlamydia test results were also collected. Patient identifiers were sent directly from the laboratories to the National HPV Vaccination Program Register, to obtain HPV vaccination histories. Samples underwent HPV genotyping using Seegene Anyplex II HPV 28 assay.

    RESULTS: Between April and July 2018, 362 residual samples were collected, the majority (60.2%) of which were cervical swabs. Demographic data and vaccination histories were received for 357 (98.6%) women (mean age 21.8, SD 2.0). Overall, 65.6% of women were fully vaccinated, 9.8% partially, and 24.7% unvaccinated. The majority (86.0%) resided in a major city, 35.9% were classified in the upper quintile of socioeconomic advantage and chlamydia positivity was 7.8%.The prevalence of quadrivalent vaccine-targeted types (HPV6/11/16/18) was 2.8% (1.5-5.1%) overall with no differences by vaccination status (p = 0.729). The prevalence of additional nonavalent vaccine-targeted types (HPV31/33/45/52/58) was 19.3% (15.6-23.8%). One or more oncogenic HPV types were detected in 46.8% (95% CI 41.6-52.0%) of women.

    CONCLUSIONS: HPV testing of residual chlamydia specimens provides a simple, feasible method for monitoring circulating genotypes. Applied on a larger scale this method can be utilised to obtain a timely assessment of nonavalent vaccine impact among young women not yet eligible for cervical screening.

  20. Salmons B, Lim PY, Djurup R, Cardosa J
    Vaccine, 2018 10 29;36(45):6623-6630.
    PMID: 30293762 DOI: 10.1016/j.vaccine.2018.09.062
    A candidate hand, foot, and mouth disease vaccine comprising of human enterovirus A71 (EV-A71) virus-like particles (VLPs) was tested in rabbits to evaluate the potential local and systemic effects of this vaccine. The rabbits received more than double the full human dose and one additional dose according to the n + 1 recommended scheme. The three doses were given mixed with Alhydrogel adjuvant as intramuscular (IM) injections. Vaccinations were well-tolerated, with no indication of overt toxicity in any parameter observed. An EV-A71 specific immune response in the form of antibodies that specifically reacted with the virus capsid proteins VP1 and VP0, the complete VLP, and EV-A71 viruses of different subgenotypes to that of the vaccine could be demonstrated. A boosting effect in the form of higher EV-A71 specific antibody titers was observed after the subsequent doses, and these enhanced titers were shown to be statistically significant in one-way ANOVA analyses. Fortnightly intramuscular administration of EV-A71 VLP vaccine did not result in any test article-related changes in immunotoxicity as defined by increased serum IL-6, and in general IL-6 concentrations remained below the lower limit of quantitation for the majority of animals throughout the study. Although increased indicators of inflammation at the injection site were observed in animals sacrificed immediately after the last vaccination, these largely reversed at the end of the recovery phase. No findings suggestive of systemic or delayed toxicity were recorded in this independently conducted study. In conclusion, repeated IM administration of the EV-A71 VLP vaccine were locally and systemically well-tolerated in rabbits and immunogenic, supporting the clinical development of the vaccine.
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