Jan Poolman[edit]

Dr. Jan T. Poolman (1951) is a microbiologist and bacterial vaccinologist and was during his career at GSK and at Johnson & Johnson together with his R&D teams he contributed to the development of a series of bacterial vaccines.

As Head & Vice President of Bacterial Vaccines R&D at GlaxoSmithkline (GSK) Biologicals, Rixensart, Belgium he contributed to the development and licensure of a series of eight pediatric vaccines against the major bacterial pathogens Haemophilus influenza type B (Hib), pertussis (Bordetella pertussis), meningococcus (Neisseria meningitidis) and pneumococcus (Streptococcus pneumoniae), forming the majority of the bacterial vaccines currently used in national immunization programs globally. These eight vaccines are: DTaP-HB-IPV-Hib (Infanrix-Hexa), DTwP-HB-Hib (Tritanrix), DTaP-HB-IPV (Pediarix), Tdap (Boostrix), Hib-MenC-TT (Menitorix), 10-valent pneumococcal conjugate (Synflorix), Hib-MenCY-TT (Menhibrix), and MenACWY-TT (Nimenrix). (Abbreviations: D/d=diphtheria; T=tetanus; aP/ap=acellular pertussis; HB=hepatitis B; IPV=inactivated polio vaccine; Hib= Haemophilus influenzae type B; wP=inactivated whole cell pertussis; MenACWY=meningococcal type A/C/W/Y; TT=tetanus toxoid carrier protein).

In his role as the Head of Bacterial Vaccines at Johnson & Johnson (JnJ)[1][2][3] he focused on the development of bacterial vaccines against extraintestinal pathogenic Escherichia coli (ExPEC) and Staphylococcus aureus for adults. ExPEC and S. aureus are two of the leading causes of bacteremia and sepsis[4], and vaccines to prevent these diseases are urgently needed in developed and developing countries.

During his tenure at Johnson & Johnson he has built and led an R&D team and contributed, together with this team, to the development of an Escherichia coli /ExPEC vaccine candidate, currently under evaluation in a clinical phase 3 efficacy study (E.mbrace, NCT04899336). In addition, he and his team have worked on a S. aureus vaccine candidate

Dr. Poolman has been a serial inventor throughout his career, during which time, over 30 intellectual patent families were created from his research and development.[5]

Early life & education[edit]

Jan Poolman was born on June 16, 1951, in Broek in Waterland in the Netherlands. He lost his father when he was only 2 years old and grew up with his mother and sister on his uncle’s cattle farm. This situation triggered his ongoing fascination with life and its natural enemies, pathogens, already early in life. Moreover, he learned at an early age that one must work hard to achieve one’s goals and dreams

Dr Poolman studied chemistry at the University of Amsterdam (UVA) (1969-1975). After his specialization in microbiology, combining his interest in chemistry, biology and bacterial pathogens he obtained his master’s degree in 1975.

Research & career as bacteriologist and bacterial vaccinologist[edit]

1976 – 1986 Laboratory of Medical Microbiology and Infectious Diseases in Amsterdam[edit]

Academic - Diagnostics and Epidemiology – Focus: Meningitis

Jan Poolman started his PhD in 1976 as assistant Professor of Microbiology under the supervision of Professor Dr. H. C. (Bob) Zanen, Head of Medical Microbiology and Infectious Diseases at the University of Amsterdam (UVA) on the topic of diagnostics and epidemiology of meningitis. A collection of strains of the three major bacterial pathogens that cause meningitis: meningococcus, pneumococcus and Hib, coupled with epidemiological data obtained by serotyping all isolates, was developed by this research team.

On 17 December 1981 he obtained his PhD in the Medical Faculty for his thesis entitled “Surface structure of Neisseria meningitidis: some implications for the epidemiology and pathogenesis of meningococcal diseases”.

In 1982 Dr. Poolman was awarded a one-year post-doctoral Fogarty Fellowship research position at the University of Washington in Seattle, funded by the National Institutes of Health. The Seattle laboratory specialized in sexually transmitted infectious diseases. He worked on the development of monoclonal antibodies against N. gonorrhoeae.

After his return from the USA, he worked at the UVA until 1986. In the 10 years that he worked at the Laboratory of Medical Microbiology and Infectious Diseases of the UVA, the team built the Reference Laboratory for Bacterial meningitis of the Netherlands, a globally recognized international reference laboratory. In addition, Dr. Poolman and his team introduced the international standard in the field of N. meningitidis serogroup B serotyping in 1985, which is still widely in use today.... In 1989, they pinpointed PorA as key bactericidal target for a serogroup B meningococcal vaccine

1986 – 1996 Dutch National Institute for Public Health and the Environment – RIVM Bilthoven, NL[edit]

Governmental public health institute – Bacterial Vaccinology – Focus: Pertussis & Meningitis

Dr. Poolman changed direction in 1986 to follow his ultimate dream: to develop vaccines that would prevent bacterial meningitis caused by meningococcus, pneumococcus and Hib. He started to work at the RIVM in 1986, at that time still a national vaccine manufacturer in the Netherlands. While at RIVM he created a team as Head of Vaccine Development and Immune Mechanisms and worked on the development of DTaP-(HB)-IPV-Hib to replace the DTwP-IPV vaccine, and the development of vaccines against serogroup B meningococcus, pneumococcus and Hib. Collaborations with the US company Praxis Biologics with respect to one of the first Hib conjugate vaccines and with the Italian company Sclavo regarding an acellular pertussis, were initiated to ultimately develop the extended pediatric combination DTaP-(HB)-IPV-Hib vaccine.

Dr. Poolman and his team were involved in the introduction of the outer membrane vesicle vaccine (OMV) technology at the RIVM. The OMV technology is currently still in use at the Dutch vaccine institute IntraVacc, that resulted from the vaccine R&D department of the RIVM in 2013. Dr. Poolman and his team developed a hexavalent (6-valent) PorA containing meningococcal outer membrane vesicle vaccine against serogroup B meningococci. This vaccine was later further developed at the RIVM into a 9-valent vaccine and externalized in due course.

In the book Fighting a fearful disease: controlling New Zealand's meningococcal B epidemic by Janet Tyson with Richard Norman, Dr. Poolman is being cited on the topic of how to control the epidemic (pp 52). “Given that what you need is strain-specific protection to quell an epidemic, I would go with the tried and true, the old technology of the outer membrane vesicle vaccine, and try to get one of the producers to make one for the New Zealand strain.” Ultimately, the New Zealand authorities sponsored the development of a New Zealand strain-specific outer membrane vesicle vaccine that was instrumental in controlling the meningitis epidemic that had continued unchecked for more than a decade.

Contribution to development of pneumococcal vaccines – the Dutch Nordic Consortium[edit]

In 1990 the Dutch Nordic Consortium (DNC), a collaboration between public health institutions from the Netherlands, Sweden, Denmark, Norway and Finland was established with the aim to cooperate in the development of new vaccines for developing countries. The DNC started a pilot tetravalent pneumococcal conjugate vaccine (PCV-4) project. Dr. Poolman led this project as project leader on behalf of RIVM and DNC.

The goal was to develop and clinically assess a pneumococcal conjugate vaccine for the developing world, a project supported by the European Union. The laboratory scale development of saccharide-protein conjugates started at the RIVM in the Netherlands and at the Swedish Bacteriological Laboratory in 1993.

In 1996 Dr. Poolman decided to move to the private sector. His conclusion at that time was that “Vaccine development and production is no longer possible in the public sector due to inadequate resources, lack of infrastructure and too little will to make it a success”. A case in point - the DNC resulted in the development of a 4-valent PCV, that was demonstrated to be safe and immunogenic in two phase 1 studies in adults and toddlers in Finland. An efficacy study that was planned in infants in Asia was never approved and the DNC PCV-4 project ended in 2000.

Pertussis efficacy issue with whole cell Pertussis vaccine of RIVM[edit]

In 1996 shortly before leaving the RIVM, Dr. Poolman notified the Dutch National Health Inspectorate of an efficacy issue with the Dutch whole cell pertussis vaccine. Dr. Poolman was asked as expert for advice to the National Health Council. In April 2004 the advice of the Council to the government was to revise the Dutch national vaccination program and stop using the Dutch whole cell pertussis vaccine and switch to an acellular pertussis vaccine combination

Dr. Poolman decided to make the Dutch public aware of the efficacy issue of the Dutch whole cell Pertussis vaccine. He published the story in “De Telegraaf”, a Dutch newspaper, on November 19, 2004.

1997 – 2011 SmithKline Beecham Biologicals now GSK – Rixensart and Wavre-Nord Belgium[edit]

Pharmaceutical industry - Bacterial Vaccinology – Focus: meningitis and pertussis

In 1996, Dr. Poolman commenced his tenure as the Head of Bacterial Vaccines at Smith Kline Beecham Biologics (SBBio) located in Rixensart, Belgium. The company later merged with Glaxo Wellcome to become GlaxoSmithKline (GSK) in 2000.

Dr. Poolman and his team, under the supervision of Dr. Jean Stephenne (president) and Dr. Jean-Paul Prieels (global head of R&D), contributed to the research and development of eight new vaccines: DTaP-HB-IPV-Hib (Infanrix-Hexa); DTwP-HB-Hib (Tritanrix), DTaP-HB-IPV (Pediarix); Tdap (Boostrix); Hib-MenC-TT (Menitorix); 10-valent pneumococcal conjugate (Synflorix); Hib-MenCY-TT (Menhibrix), and MenACWY-TT (Nimenrix). These vaccines have constituted, and continue to contribute, to National Immunizations Programs globally.

With the DTwP-HB-Hib Tritanrix vaccine, GSK re-wrote the course of history for Middle- and Low-income countries. By adding hepatitis B and Hib to the existing DTwP vaccine, the cornerstone of worldwide pediatric immunization, allowed for the worldwide coverage against hepatitis B and Hib. Additionally, by the introduction of tiered pricing, meaning no or only marginal profit on vaccines sold to low-income countries, the price of the new vaccine could remain affordable.

During his time at GSK Dr. Poolman was able to contribute to the development and licensure of the vaccines he had always dreamed of to produce. And while still unsolved challenges remained, such as the development and licensing of an effective serogroup B meningococcus vaccine, he nevertheless made a lasting contribution to global health through prophylaxis.

2011 – current Johnson & Johnson Bacterial Vaccines – Leiden, NL[edit]

Pharmaceutical industry - Bacterial Vaccinology – Focus: E. coli/ExPEC and S. aureus for older adults

In 2011 Johnson and Johnson (JnJ) started a vaccine pillar by acquiring Crucell, a small vaccine player with their headquarters located in Leiden, the Netherlands. In that same year 2011, Dr. Poolman was appointed Head of Bacterial Vaccines at JnJ, Leiden, the Netherlands. During his period at JnJ Dr. Poolman changed focus from pediatric vaccines to the development of vaccines for older adults, in particular, vaccines directed against E. coli/ExPEC and S. aureus.

ExPEC and S. aureus are the leading bacterial pathogens causing bacteremia/sepsis, healthcare-associated infections and global deaths associated with antimicrobial resistance. A global analysis of adult E. coli bacteremia incidence in high-income countries estimated an increasing incidence rate after the age of 60. Estimated incidence rates of 110, 154 and 319 per 100 000 person-years of persons aged 60-69 years old, 70-79 years old and 80 years and older, respectively, has been reported. These diseases are particularly important given the aging demographic globally. There are currently no prophylactic vaccines available.

Over a period of twelve years, Dr. Poolman and his team built a bacterial vaccines department and developed, by way of enzymatic in vivo bioconjugation, the O-antigen glycoconjugate E. coli/ExPEC vaccine candidate ExPEC9V to prevent invasive E. coli disease (bacteremia/sepsis). ExPEC9V is currently being tested in the Phase 3 E.mbrace efficacy study (NCT04899336) and in the Phase 3 E.ngage study in combination with an influenza vaccine (NCT06134804).

In parallel, Dr. Poolman and his team worked on the development of a S. aureus vaccine candidate to prevent S. aureus infectious diseases.

Other activities of Dr. Poolman in vaccines and infectious diseases[edit]

2016 - 2019 - Tuberculosis Vaccine Initiative (TBVI).[bewerken | brontekst bewerken][edit]

From 2016-2019, Dr. Poolman was a member of the Advisory Committee of the non-profit foundation TuBerculosis Vaccine Initiative (TBVI).

The TBVI is a Research and Innovation partnership that facilitates the discovery and development of new, safe and effective TB vaccines that are accessible and affordable for all people. TBVI works through the Global TB Vaccine Partnership with global stakeholders to strengthen global and European cooperation and coordination, and it identifies research gaps to move the field forward.

2023 - current - Jenner Vaccine Foundation (JVF)[edit]

Dr. Poolman has been active as Trustee of the Jenner Vaccine Foundation since 2023.

The Foundation seeks to enhance philanthropic support of vaccinology and is currently evaluating options for enhanced fundraising activities. The Foundation currently supports vaccine research and development through the Jenner Institute. The Foundation Board appoints the Director of the Institute, elects Jenner Investigators (currently numbering 29) and has funded space and facilities for vaccine research and development at Oxford University for human vaccines and the Pirbright Institute for veterinary vaccines.

2018 - current - World Vaccine Congress Europe, AMR and Bacterial Vaccine sessions[edit]

Dr. Poolman is active as chair and speaker of the AMR and Bacterial Vaccine session at the World Vaccine Congress Europe since 2018.

2019 - current - WHO Technical Advisory Group on Vaccines and Antimicrobial resistance[edit]

Dr. Poolman is active as observer to the WHO Technical Advisory Group on Vaccines and Antimicrobial resistance since 2019.

Awards[edit]

1982 NIH Fogarty Fellowship - Dr Poolman was awarded a one-year post-doctoral NIH Fogarty Fellowship at the university of Washington in Seattle in 1982.

1989 W.R.O. Goslings-award - Dr. Poolman was awarded the W.R.O. Goslings-award of the Dutch Association of Infectious Diseases in 1989.

Publications Dr. Poolman[edit]

Dr. Poolman has been an author or co-author of more than 300 scientific publications in his career of over 45 years.

https://www.researchgate.net/profile/Jan-Poolman

Selected publications[edit]

Meningococcus B publications[edit]

Frasch, C. E., Zollinger, W. D. and Poolman, J. T. (1985) Serotype Antigens of Neisseria meningitidis and a Proposed Scheme for Designation of Serotypes. Reviews of Infectious Diseases Vol. 7 (4) pp 504-510. Doi: 10.1093/clinids/7.4.504.

Poolman, J. T. et al. (1986) Meningococcal serotypes and serogroup B disease in North-West Europe. The Lancet Vol. 2 (8506) pp 555-558. Doi: 10.1016/s0140-6736(86)90123-6.

Cartwright, K. et al. (1999) Immunogenicity and reactogenicity in UK infants of a novel meningococcal vesicle vaccine containing multiple class 1 (PorA) outer membrane proteins. Vaccine Vol. 17 (20-21) pp 2612-2619. Doi: 10.1016/s0264-410x(99)00044-4.

Tappero, J. W. et al. (1999) Immunogenicity of 2 serogroup B outer-membrane protein meningococcal vaccines: a randomized controlled trial in Chile. JAMA vol. 281 (16) pp 1520-1527. Doi: 10.1001/jama.281.16.1520.

MenACWY and HibCY publications[edit]

Knuf, M. et al. (2010) A dose-range study assessing immunogenicity and safety of one dose of a new candidate meningococcal serogroups A, C, W-135, Y tetanus toxoid conjugate (MenACWY-TT) vaccine administered in the second year of life and in young children. Vaccine Vol. 28 (3) pp 744-53. Doi: 10.1016/j.vaccine.2009.10.064.

Nolan, T. et al. (2011) Immunogenicity and safety of an investigational combined Haemophilus influenzae type B-Neisseria meningitidis serogroups C and Y-tetanus toxoid conjugate vaccine. The Pediatric infectious disease journal Vol. 30 (3) pp 190-196. Doi: 10.1097/INF.0b013e3181fcb2bf.

Poolman, J. & Borrow, R. (2011) Hyporesponsiveness and its clinical implications after vaccination with polysaccharide or glycoconjugate vaccines. Expert review of vaccines Vol. 10 (3) pp 307-322. Doi: 10.1586/erv.11.8.

Harrison, O.B. et al. (2013) Description and nomenclature of Neisseria meningitidis capsule locus. Emerg Infect Dis Vol. 19 (4) pp 566-73. Doi: 10.3201/eid1904.111799.

Hib-DTaP publications[edit]

Peeters, C. C. A. M. et al. (1992) Synthetic trimer and tetramer of 3-beta-D-ribose-(1-1)-D-ribitol-5-phosphate conjugated to protein induce antibody responses to Haemophilus influenzae type b capsular polysaccharide in mice and monkeys. Infection & Immunity Vol. 60 (5) pp 1826-1833. Doi: 10.1128/iai.60.5.1826-1833.1992

Poolman, J. T. et al. (2001) Clinical relevance of lower Hib response in DTPa-based combination vaccines. Vaccine Vol. 19 (17-19) pp 2280-2285. Doi: 10.1016/s0264-410x(00)00517-x.

Capiau, C. et al. (2003) Development and clinical testing of multivalent vaccines based on a diphtheria-tetanus-acellular pertussis vaccine: Difficulties encountered and lessons learned. Vaccine Vol. 21 (19-20) pp 2273-2287. Doi: 10.1016/s0264-410x(03)00107-5

Poolman, J. T. & Hallander, H. O. (2007) Accellular pertussis vaccines and the role of pertactin and fimbriae. Expert Review of Vaccines Vol. 6 (1) pp 47-56. Doi: 10.1586/14760584.6.1.47.

Pneumococcus publications[edit]

Alexander J.E. et al. (1994) Immunization of Mice with Pneumolysin Toxoid Confers a Significant Degree of Protection against At Least Nine Serotypes of Streptococcus pneumoniae. Infection and Immunity Vol. 62 (12) pp 5683-5688. Doi:10.1128/iai.62.12.5683-5688.1994

Prymula, R. et al. (2006) Pneumococcal capsular polysaccharides conjugated to protein D for prevention of acute otitis media caused by both Streptococcus pneumoniae and non-typable Haemophilus influenzae: A randomised double-blind efficacy study. The Lancet Vol. 367 No. 9512 pp 740-748. Doi: 10.1016/S0140-6736(06)68304-9.

Dagan, R., Poolman, J. & Siegrist, C. A. (2010) Glycoconjugate vaccines and immune interference: A review. Vaccine Vol. 28 (34) pp 5513-23. Doi: 10.1016/j.vaccine.2010.06.026.

Rioux, S. et al. (2011) Transcriptional regulation, occurrence and putative role of the Pht family of Streptococcus pneumoniae. Microbiology (Reading) Vol. 157 (Pt 2) pp 336-348. Doi: 10.1099/mic.0.042184-0.

E. coli/ExPEC publications[edit]

Poolman, J. T. & Wacker, M. (2016) Extraintestinal Pathogenic Escherichia coli, a Common Human Pathogen: Challenges for Vaccine Development and Progress in the Field. J Infect Dis. Vol. 213 (1) pp 6-13. Doi: 10.1093/infdis/jiv429.

Huttner, A. et al. (2017) Safety, immunogenicity, and preliminary clinical efficacy of a vaccine against extraintestinal pathogenic Escherichia coli in women with a history of recurrent urinary tract infection: a randomised, single-blind, placebo-controlled phase 1b trial. Lancet Infect Dis. 2017 May;17(5):528-537. Doi: 10.1016/S1473-3099(17)30108-1.

Frenck Jr, R. W. et al. (2019) Safety and immunogenicity of a vaccine for extra-intestinal pathogenic Escherichia coli (ESTELLA): a phase 2 randomised controlled trial. Lancet Infect Dis. Vol. 19 (6) pp 631-640. Doi: 10.1016/S1473-3099(18)30803-X.

Fierro, C. A. et al. (2023). Safety, Reactogenicity, Immunogenicity, and Dose Selection of 10-Valent Extraintestinal Pathogenic Escherichia coli Bioconjugate Vaccine (VAC52416) in Adults Aged 60-85 Years in a Randomized, Multicenter, Interventional, First-in-Human, Phase 1/2a Study. Open Forum Infectious Diseases, 10(8), ofad417. doi:10.1093/ofid/ofad417

S. aureus publications[edit]

Poolman, J. T., & Anderson, A. S. (2018). Escherichia coli and Staphylococcus aureus: leading bacterial pathogens of healthcare associated infections and bacteremia in older-age populations. Expert Review of Vaccines Vol. 17 (7) pp 607-618. Doi:10.1080/14760584.2018.1488590.

Poolman, J. T. (2020) Expanding the role of bacterial vaccines into life-course vaccination strategies and prevention of antimicrobial-resistant infections. NPJ Vaccines. Vol. 5 (84) pp 1-12. Doi: 10.1038/s41541-020-00232-0.

Fernandez, J. et al. (2022) Vaccination With Detoxified Leukocidin AB Reduces Bacterial Load in a Staphylococcus aureus Minipig Deep Surgical Wound Infection Model. J Infect Dis. Vol. 225 (8) pp 1460-1470. Doi: 10.1093/infdis/jiab219.

References[edit]

^
^ Jump up to:^a ^b
^ Jump up to:^a ^b .
^ Fierro, C. A. et al. Safety, Reactogenicity, Immunogenicity, and Dose Selection of 10-Valent Extraintestinal Pathogenic Escherichia coli Bioconjugate Vaccine (VAC52416) in Adults Aged 60-85 Years in a Randomized, Multicenter, Interventional, First-in-Human, Phase 1/2a Study. Open Forum Infect. Dis. 10, ofad417, doi:10.1093/ofid/ofad417 (2023).
^ Frenck, R. W., Jr. et al. Safety and immunogenicity of a vaccine for extra-intestinal pathogenic Escherichia coli (ESTELLA): a phase 2 randomised controlled trial. The Lancet. Infectious diseases 19, 631-640, doi:10.1016/S1473-3099(18)30803-X [doi] (2019).
^ Huttner, A. et al. Safety, immunogenicity, and preliminary clinical efficacy of a vaccine against extraintestinal pathogenic Escherichia coli in women with a history of recurrent urinary tract infection: a randomised, single-blind, placebo-controlled phase 1b trial. The Lancet. Infectious diseases 23, 30108-30101, doi:10.1016/S1473-3099(17)30108-1 [doi] (2017).
^ Poolman, J. T. & Wacker, M. Extraintestinal Pathogenic Escherichia coli, a common human pathogen: challenges for vaccine development and progress in the field. Journal of Infectious Diseases 213, 6-13, doi:10.1093/infdis/jiv429 (2016).
^ Jump up to:^a ^b Fernandez, J. et al. Vaccination With Detoxified Leukocidin AB Reduces Bacterial Load in a Staphylococcus aureus Minipig Deep Surgical Wound Infection Model. J. Infect. Dis. 225, 1460-1470, doi:10.1093/infdis/jiab219 (2022).
^ Jump up to:^a ^b Poolman, J. T. & Anderson, A. S. Escherichia coli and Staphylococcus aureus: leading bacterial pathogens of healthcare associated infections and bacteremia in older-age populations. Expert review of vaccines 17, 607-618, doi:10.1080/14760584.2018.1488590 (2018).
^ Jump up to:^a ^b Poolman, J. T. Expanding the role of bacterial vaccines into life-course vaccination strategies and prevention of antimicrobial-resistant infections. NPJ Vaccines 5, 84, doi:10.1038/s41541-020-00232-0 (2020).
^ Jump up to:^a ^b ^c Poolman, J. Building teams to create innovative new vaccines. Hum. Vaccin. Immunother. 14, 2808-2810, doi:10.1080/21645515.2018.1530523 (2018).
^ Album_Academicum_UVA. Album Academicum – UVA Professors and PhD graduates from 1632 to this day, url=https://albumacademicum.uva.nl/cgi/b/bib/bib-idx?c=ap;cc=ap;lang=en;q1=cell%20walls;rgn1=educationdiscipline;type=boolean;view=reslist;sort=achternaam;fmt=long;page=reslist;size=1;start=13 (
^ Frasch, C. E., Zollinger, W. D. & Poolman, J. T. Serotype antigens of Neisseria meningitidis and a proposed scheme for designation of serotypes. Rev. Infect. Dis. 7, 504-510, doi:10.1093/clinids/7.4.504 (1985).
^ Saukkonen, K., Leinonen, M., Abdillahi, H. & Poolman, J. T. Comparative evaluation of potential components for group B meningococcal vaccine by passive protection in the infant rat and in vitro bactericidal assay. Vaccine 7, 325-328, doi:10.1016/0264-410x(89)90194-1 (1989).
^ Hendriks, J. in Immunization and States - The Politics of Making Vaccines (ed Stuart Blume and Baptiste Baylac-Paouly) Ch. 1, ( Routledge, 2021).
^ van der Ley, P., van der Biezen, J. & Poolman, J. T. Construction of Neisseria meningitidis strains carrying multiple chromosomal copies of the porA gene for use in the production of a multivalent outer membrane vesicle vaccine. Vaccine 13, 401-407, doi:10.1016/0264-410x(95)98264-b (1995).
^ van der Voort, E. R. et al. Specificity of human bactericidal antibodies against PorA P1.7,16 induced with a hexavalent meningococcal outer membrane vesicle vaccine. Infect Immun 64, 2745-2751, doi:10.1128/iai.64.7.2745-2751.1996 (1996).
^ Claassen, I. et al. Production, characterization and control of a Neisseria meningitidis hexavalent class 1 outer membrane protein containing vesicle vaccine. Vaccine 14, 1001-1008, doi:10.1016/0264-410x(96)00020-5 (1996).
^ Peeters, C. C. et al. Phase I clinical trial with a hexavalent PorA containing meningococcal outer membrane vesicle vaccine. Vaccine 14, 1009-1015, doi:10.1016/0264-410x(96)00001-1 (1996).
^ Cartwright, K. et al. Immunogenicity and reactogenicity in UK infants of a novel meningococcal vesicle vaccine containing multiple class 1 (PorA) outer membrane proteins. Vaccine 17, 2612-2619 (1999).
^ Tyson, J. & Norman, R. Fighting a Fearful Disease: Controlling New Zealand's Meningococcal B Epidemic. (Institute of Policy Studies, 2007).
^ Hendriks, J. & Blume, S. Why might regional vaccinology networks fail? The case of the Dutch-Nordic Consortium. Global Health 12, 38, doi:10.1186/s12992-016-0176-6 (2016).
^ Health_Council_of_the_Netherlands. Vaccination against pertussis. Health Council of the Netherlands. Publication no. 2004/04., (The Hague, 2004).
^ Bonten, M. et al. Epidemiology of Escherichia coli Bacteremia: A Systematic Literature Review. Clin. Infect. Dis. 72, 1211-1219, doi:10.1093/cid/ciaa210 (2021).