6 November 2023 | Changes to customer log in process

We have made improvements to the way our customers access their account information.

10 July 2023 | New panel of antibodies specific to SARS-CoV-2 variants available for vaccine researchers

Antibodies specific to SARS-CoV-2 WA01 (Wuhan) and Omicron, Delta variants produced to help speed the development and testing of vaccines globally.

24 April 2023 | New NIBSC reference materials available

Our NIBSC biological standards and reference materials catalogue has been updated, including WHO standards for SARS-CoV-2, influenza and other quality control reagents.

13 April 2023 | New MHRA cell therapy research evaluates immune-stimulant cancer therapies to reduce side effects for patients

Findings from research by the Medicines and Healthcare products Regulatory Agency (MHRA) have been published, evaluating two different approaches to cancer therapies which harness the immune system to determine which better targets cancer cells and would reduce side effects for patients.

6 April 2023 | Happy 75th Anniversary to the World Health Organization

On this day in 1948, the United Nations (UN) came together to establish a global organisation that promotes health, keeps the world safe, and serves the vulnerable.

8 March 2023 | International Women’s Day – meet the women at the forefront of STEM

We are celebrating International Women’s Day 2023 with a series of profiles featuring colleagues from across the MHRA.

26 January 2023 | NIBSC Reference Reagent for DNA extraction of gut microbiome samples

Following the successful establishment of the first WHO International Reference Reagent for microbiome analysis by Next-Generation Sequencing we have developed a complementary reference reagent for the harmonisation of DNA extraction of gut microbiome samples which is now available at the NIBSC catalogue.

24 January 2023 | Research reagent for Mpox antibodies now available

We have developed a key laboratory reagent to advance and standardise assessment of antibody responses to Mpox elicited by infection or vaccination, in partnership with the Coalition for Epidemic Preparedness Innovations (CEPI).

1 November 2022 | Unique opportunity for healthcare professionals to influence future MHRA safety communications and safety reporting systems

Healthcare professionals asked to share their views on how they want to receive safety information from the UK medicines and medical devices regulator.

11 October 2022 | Physical Standards for Adeno-associated virus (AAV) Gene Therapy

Download the full report for the Regulators Pioneer Funded Project 2021-2022

18 March 2022 | Changes to the look of our website

We have made some small changes to the look of our website, NIBSC.org. We are making similar changes to our other websites, so that our sites look more like each other. You can still use the site as normal. If you have any questions, please email enquiries@nibsc.org.

10 January 2022 | Our First WHO International Standard (IS) for Harmonizing the Biological Activity of Bevacizumab

Our leading scientist, Dr Haiyan Jia, has recently published a paper on our first WHO International Standard for Harmonizing the Biological Activity of Bevacizumab

17 November 2021 | Pay NIBSC invoices easily

We have introduced a new way to pay NIBSC invoices, via NIBSC Pay.

1 November 2021 | Using environmental surveillance to track the most recent coronavirus variant AY.4.2

The latest research from the National Institute of Biological Standards and Control (NIBSC) confirms the increasing frequency of coronavirus Delta sub-variant AY.4.2 found in wastewater samples.

27 October 2021 | NIBSC polio vaccine nOPV2 recommended for wider use

Scientists from the National Institute for Biological Standards and Control (NIBSC) played a leading role in the development of a the novel oral polio vaccine type 2 (nOPV2) as an essential new tool in the fight against vaccine-derived poliovirus type 2 (cVDPV2).

25 October 2021 | New range of reference standards

We are pleased to introduce new standards for SARS-CoV-2, influenza and other quality control reagents.

15 September 2021 | Using proteomics to understand survival during meningococcal outbreak

NIBSC scientists identified a protein called factor H binding protein (fHbp) found on the surface of meningococci to be associated with severe invasive meningococcal disease.

6 August 2021 | Our development of the MAT supports the safe testing of novel vaccines

Our development of the MAT supports the safe testing of novel vaccines to overcome infections such as Shigella and iNTS.

16 July 2021 | TRANSVAC-DS: Towards a sustainable European vaccine infrastructure

The NIBSC works to support the design and establishment of a sustainable European vaccine infrastructure as part of a Horizon 2020 EC-funded project.

14 July 2021 | UK Stem Cell Bank secures National Institute for Health Research grant

The UK Stem Cell Bank has been awarded a £1.2m NIHR grant to secure the UK Public repository of human embryonic stem cell lines, and provide further high-quality, ‘regulator-ready’ cell lines as starting materials for advanced therapies.

05 July 2021 | SoGAT diagnostic forum discusses COVID-19

Last month, established teams embraced new ways of working, when NIBSC hosted the 29th meeting and the first virtual workshop of SoGAT, focusing on molecular diagnostics for SARS-CoV-2.

02 July 2021 | Budding scientist Evette a ’people’s choice’ winner

Congratulations to second year NIBSC PhD student Evette Hillman who recently walked away with a £600 prize and a ticket to the national finals after being crowned ‘people’s choice’ and overall winner of her alma mater Warwick University’s ‘Three Minute Thesis Challenge (3MT)’.

21 June 2021 | Prime Minister kicks off major new science initiative at visit of NIBSC

The Prime Minister was able to see first-hand the pivotal role NIBSC has played in getting safe and effective COVID-19 vaccines to the UK public during the pandemic.

18 June 2021 | Using environmental surveillance to track coronavirus variants

The latest research from the National Institute of Biological Standards and Control (NIBSC) confirms that the testing of wastewater is an effective tool for monitoring coronavirus variants.

Guidance for manufacturers of biological medicines - independent batch release in the United Kingdom following the UKs departure from the EU

Certification of batches of immunological medicinal products or medicinal products derived from human blood or plasma products (including plasma pools) if the UK leaves the EU without a deal.

20 April 2021 | NIBSC seeking partners for the development of working standards for SARS-CoV-2 variants

The NIBSC is seeking partners for sourcing serum or plasma from individuals vaccinated against and/or recovered from infection with SARS-CoV-2 variants for the development of antibody working standards and reference panels.

26 March 2021 | NIBSC to support pioneering gene therapy centre

The National Institute for Biological Standards and Control has partnered with The University of Sheffield and other scientific institutions across England and Wales to establish a new ‘Gene Therapy Innovation and Manufacturing Centre’ (GTIMC).jjjjj

18 March 2021 | NIBSC develops panel of antibody controls for cytokine release assays

Scientists from the National Institute of Biological Standards and control have developed the first antibody reference panel for the qualification and validation of cytokine release assay platforms.

4 March 2021 | WHO International Standards for Bevacizumab and Trastuzumab now available

The National Institute for Biological Standards and Control (NIBSC) has expanded its range of monoclonal antibody standards.

4 February 2021 | NIBSC supporting the Measurement for Recovery Programme

The National Institute for Biological Standards and Control (NIBSC) has partnered with the National Physical Laboratory (NPL) to support UK companies by providing specialist measurement advice and services from our biological standardisation experts.

26 January 2021 | NIBSC Centre for AIDS Reagents supporting coronavirus and malaria research

The NIBSC Centre for AIDS Reagents (CFAR) repository is further expanding its remit to support research on SARS-CoV-2 by providing a selection of viruses, plasmids, cell lines, recombinant proteins and antibodies.

14 January 2021 | New and replacement WHO standards and guidelines established by ECBS

New and replacement WHO standards developed by the NIBSC have been established by the WHO Expert Committee on Biological Standardisation (ECBS).

8 January 2021 | NIBSC statement on batch testing for the COVID-19 Vaccine AstraZeneca

We are continuously looking at ways to speed up the vital independent batch testing of Covid-19 vaccines without compromising safety.

22 December 2020 | Independent batch release testing of COVID-19 (coronavirus)

As is the case for current, licensed vaccines, the quality of each batch of any potential COVID-19 vaccine will be evaluated by an independent laboratory

8 December 2020 | NHS Winter multiplex diagnostic control now available

The National Institute for Biological Standards and Control (NIBSC) has formulated a series of controls to assist diagnostic laboratories throughout the forthcoming winter respiratory virus season.

2 December 2020 | UK medicines regulator gives approval for first UK COVID-19 vaccine

The first COVID-19 vaccine for the UK, developed by Pfizer/BioNTech, has been given approval for use following a thorough review carried out by the Medicines and Healthcare products Regulatory Agency (MHRA).

18 November 2020 | Supporting World Antimicrobial Awareness Week 2020

Today marks the start of World Antimicrobial Awareness Week 2020. This annual event, organised by the World Health Organisation (WHO), aims to increase global awareness of antimicrobial resistance in order to stop the spread of drug-resistant infections.

23 October 2020 | Searching for coronavirus clues in sewage

A recent study conducted by scientists at the NIBSC and published in Viruses has shown that monitoring levels of coronavirus in sewage could provide an early warning for local outbreaks across the country.

20 October 2020 | NIBSC selected by CEPI to test coronavirus vaccines globally

We are delighted to announce that the National Institute for Biological Standards and Control (NIBSC) will play a key role in evaluating vaccines that have been developed for COVID-19.

08 October 2020 | NIBSC to develop International Standards for Shigella and Group B Streptococcus

The National Institute for Biological Standards and Control (NIBSC) is undertaking two separate standardisation projects to support the development of vaccines for shigella and Group B streptococcus, respectively.

03 September 2020 | Anti-SARS-CoV-2 Antibody Diagnostic Calibrant now available

The National institute for Biological Standards and Control (NIBSC) has produced a new Anti-SARS-CoV-2 Calibrant reagent to support the accurate diagnosis of COVID-19.

21 July 2020 | TRANSVAC-DS: Towards a sustainable European vaccine infrastructure

The NIBSC will be working to support the design and establishment of a sustainable European vaccine infrastructure as part of a new EC-funded project.

16 July 2020 | A standardised assay for the evaluation of typhoid vaccines

Scientists from the National Institute for Biological Standards and Control have led a multi-laboratory study to evaluate a standardised assay for determining the potency of typhoid conjugate vaccines.

10 July 2020 | Developing standards for microbiome research

Our scientists have developed the first NIBSC reference reagents and reporting system for the analysis of the microbiome by next generation sequencing methods.

25 June 2020 | Engineering antibody fragments from alpacas to fight flu

Latest research from the National Institute for Biological Standards and Control (NIBSC) shows that a novel antibody-based approach may be effective at protecting against pandemic influenza.

3 June 2020 | CE marked External Quality Control reagent now available for coronavirus (COVID-19) serology assays

A CE marked SARS-CoV-2 Serology Quality Control (QC) reagent intended for use in diagnostic laboratories is now available from the National Institute for Biological Standards and Control (NIBSC).

22 May 2020 | Diagnostics and the coronavirus: don’t let the standards slip

A CE marked SARS-CoV-2 NAT reagent ntended for use in diagnostic laboratories is now available from the National Institute for Biological Standards and Control (NIBSC).

18 May 2020 | NIBSC scientists help to design promising new polio vaccine

Scientists from the National Institute for Biological Standards Control (NIBSC) have contributed to the development of a novel vaccine believed to be a potential gamechanger in the efforts to eradicate polio.

13 May 2020 | Antibody research reagent now available for coronavirus (COVID-19)

An anti-SARS-CoV-2 antibody research reagent is now available from the National Institute for Biological Standards and Control (NIBSC).

6 May 2020 | New reagent available to support global diagnostic testing of coronavirus (COVID-19)

A new biological reagent is now available to labs around the UK and the world that will help them to set up and develop accurate diagnostic tests for coronavirus (COVID-19).

17 April 2020 | NIBSC develops first WHO International Standards for Cancer Genomes

In October 2019, the World Health Organization (WHO) Expert Committee on Biological Standardization established the first International Standards for cancer genomes using NGS (next-generation sequencing) and dPCR (digital PCR) methods.

26 February 2020 | NIBSC update on novel coronavirus (COVID-19)

The National Institute for Biological Standards and Control (NIBSC) plays a major role in assuring the quality of biological medicines, worldwide.

17 February 2020 | NIBSC to deliver training for vaccine manufacturers from developing countries

The National Institute for Biological Standards and Control will be running a series of training modules for members of the Developing Countries Vaccine Manufacturer’s Network (DCVMN) throughout 2020.

5 February 2020 | New WHO International Standards for HPV DNA now available

The NIBSC has developed new WHO International Standards for Human Papillomavirus (HPV) DNA for use in nucleic acid technology (NAT)-based assays for HPV detection and genotyping.

20 January 2020 | First WHO International Standard for Adalimumab now available

The first International Standard for Adalimumab was established by the World Health Organization (WHO) Expert Committee on Biological Standardization in October 2019.

20 December 2019 | Establishment of New and Replacement WHO Standards

The WHO Expert Committee on Biological Standardization (ECBS) held its 70th annual meeting in Geneva on the 21-25 October 2019.

18 December 2019 | New insights into antioxidant effects on monoclonal antibodies

A new study by the National Institute of Biological Standards and Control (NIBSC) has shed light on how the antioxidant enzyme thioredoxin affects the therapeutic potential of monoclonal antibodies.

1 October 2019 | Recommended vaccine strains for the southern hemisphere 2020 flu season announced

The World Health Organisation (WHO) Consultation and Information meeting on the composition of influenza virus vaccines for the southern hemisphere (Winter 2020) was held in Geneva from 23 to 27 September.

30 September 2019 | NIBSC at The Institute of Biomedical Science Congress 2019

NIBSC scientists attended the 2019 IBMS Congress that took place earlier this week. The IBMS is the professional body for biomedical scientists in the United Kingdom.

3 June 2019 | Towards animal free cell-based tests for ensuring the safety of vaccines

Research involving a collaboration between scientists at the National Institute for Biological Standards and Control and GalaxoSmithKline (GSK) has validated the use of a cell-based method for testing the safety of the meningitis B vaccine, Bexsero.

23 April 2019 | Lassa fever vaccine standards – an innovative project kicks off

In February, the Programme Advisory Committee of Lassa Biostandards met at the National Institute for Biological Standards and Control to initiate work to develop biological standards for Lassa fever virus (LASV) vaccine development.

15 March 2019 | NIBSC develop new approach to detect polio-like viruses

Researchers have used a novel next-generation sequencing (NGS) method to identify enteroviruses, such as poliovirus, within the environment.

15 March 2019 | NIBSC experts involved in Typhoid Conjugate Vaccine workshop

NIBSC scientists were recently involved in a World Health Organization (WHO) workshop to bring delegates from public health organisations, industry and regulatory agencies together to discuss guidelines on Typhoid Conjugate Vaccines (TCVs).

04 March 2019 | Innovate UK grant to support treatment of antibiotic-resistant bacterial infections

Scientists at NIBSC have been awarded over £290,000 to understand the elements of successful treatment of recurrent gut infections and deliver tools that support manufacturers to develop new therapeutic products.

17 December 2018 | NIBSC awarded over $1 million funding to support development of Lassa fever vaccines

Scientists at NIBSC have received funding worth up to $1,145,580 from CEPI (the Coalition for Epidemic Preparedness Innovations) to produce biological standards for evaluation of vaccines against Lassa fever virus (LASV).

04 December 2018 | NIBSC host webinar on the use of quality control materials

In November NIBSC hosted a joint webinar with the Institute of Biomedical Science to provide advice on the use of quality control materials covering topics such as data monitoring and choosing the right material.

05 September 2018 | Winners of Knowledge Transfer Partnership 2018 announced

NHS England has announced the winners of the 2018 Chief Scientific Officer’s (CSO) Knowledge Transfer Partnership Programme – a bespoke 12 month development programme that aims to improve patient care and identify new approaches to measurement and outcomes.

16 August 2018 | New WHO International Standards for monoclonal antibody therapies

World Health Organization (WHO) International Standards for the biological activity of monoclonal antibody products, rituximab and infliximab have been established.

28 June 2018 | NIBSC part of new grant to ensure safety of cell therapies

The National Institute of Biological Standards and Control (NIBSC) is partnering with ReNeuron to develop novel techniques, based on Next Generation Sequencing (NGS), that can assure the quality and safety of new cellular therapies entering the market.

16 June 2018 | UK Stem Cell Bank win grant from Medical Research Council

The UK Stem Cell Bank have been awarded a £2.1 million grant to continue to support the development of the EUTCD-grade cell line programme, which aims to distribute ‘regulator-ready’ stem cell lines for research and clinical applications.

15 June 2018 | NIBSC support meeting on cholera vaccine standardisation

In May representatives from academia, industry, regulatory agencies and the World Health Organization joined together to share their experiences with batch release testing of oral cholera vaccines.

25 April 2018 | World Malaria Day 2018: Fighting Malaria Resistance

This World Malaria Day, we spoke with NIBSC scientist Dr Paul Bowyer about the development of new vaccines and how his group’s work aims to better understand parasite resistance to support the development of innovative solutions to malaria.

21 March 2018 | Improvements to the way you procure standards and controls from NIBSC

This April we’re making improvements to the way you procure standards and controls from NIBSC. To allow us to make the transition, there will be a period of seven working days when NIBSC will not process orders.

12 February 2018 | NIBSC establishes first WHO international genomic reference panel for KRAS cancer mutations

Last October the World Health Organization (WHO) approved the first international standards for KRAS mutations, to underpin the harmonisation of cancer genomic diagnostics.

12 February 2018 | New UK Centre of Excellence for Engineering Biology, Metrology and Standards announced

NIBSC are collaborating with prominent UK partners in biological measurement to establish a new Centre of Excellence for Engineering Biology, Metrology and Standards.

8 February 2018 | WHO endorses new International Standard for malaria diagnosis

A new international standard has been endorsed by the World Health Organization (WHO) to support detection of Plasmodium falciparum, the parasite responsible for most cases of human malaria.

11 January 2018 | Suporting the use of new typhoid vaccines

The World Health Organization (WHO) has announced the prequalification of one of the first licensed Typhoid Conjugate Vaccines (TCVs), allowing UN agencies to buy and supply the vaccine for preventative programs.

19 December 2017 | Event review - Workshop on the scalability of iPSC technology

As a partner of the EBiSC project, the UK Stem Cell Bank at NIBSC recently co-organised a 2-day workshop for experts in the stem cell field to discuss the future of induced Pluripotent Stem Cell (iPSC) technology and the challenges ahead.

16 October 2017 | New Strategy to end Cholera

This month, the World Health Organization (WHO) launched a global campaign to reduce cholera deaths by 90% between now and 2030.

5 October 2017 | Developing the first WHO International Standard for lentiviral-based gene therapy

NIBSC are developing the first WHO International Standard for lentiviral vectors, as reported in a recent publication in Human Gene Therapy Methods.

15 August 2017 | Making safer polio vaccines with plants

A new study, involving scientists from NIBSC, has reported the production of stable poliovirus virus-like particles (VLPs) in plants.

3 August 2017 | TRANSVAC2: A European vaccine research and development infrastructure

The National Institute for Biological Standards and Control (NIBSC) is one of 26 organisations promoting innovative vaccine research and development through the new European Commission (EC)-funded initiative TRANSVAC2.

27 February 2017 | ’Regulator ready’ stem cell lines now available for clinical development

The UK Stem Cell Bank (UKSCB) is releasing its first stem cell lines suitable for development into novel cell-based medicines to researchers wishing to bring new and innovative therapies to clinical trial.

21 February 2017 | TGN1412 10 years on - learning from a clinical trials disaster

On the 10th anniversary of this event, we look back at the important role NIBSC played in uncovering what went wrong, and in making clinical trials safer for the hundreds of volunteers who take part in them every year.

19 January 2017 | New technique could enable safer production of polio vaccines

Work at NIBSC has led to a new method to produce a stable replica of poliovirus that could enable safer production of vaccines, and has just been published in PLOS Pathogens.

1 August 2016 | Supporting the Global Supply of Oral Cholera Vaccines

At the annual MHRA lecture, the Director-General of WHO Dr Margaret Chan highlighted the international effort undertaken to build a stockpile of Oral Killed Cholera vaccines.

18 July 2016 | NIBSC part of VAC2VAC consortium for assessing the safety and quality of vaccines

NIBSC is part of a public–private consortium of 19 partners tasked with developing an alternative strategy for assessing the safety and quality of human and veterinary vaccines.

6 July 2016 | Director’s statement on the EU referendum result

Statement from Dr Christian Schnider, NIBSC director, in response to the outcome of the EU referendum.

27 June 2016 | Medicines and Healthcare products Regulatory Agency statement on the outcome of the EU referendum

The Agency’s response to the outcome of the EU referendum.

20 June 2016 | CE-marked Clinical Virology Multiplex I: Immunodeficiency Panel for NAT

NIBSC are pleased to announcea further expansion to our range of CE-marked Clinical Virology working reagents for Nucleic Acid Amplification Tests (NAT); the Clinical Virology Multiplex I: Immunodeficiency Panel.

5 November 2015 | NIBSC Ebola reference reagents endorsed as global standards by WHO

Ebola reference reagents produced by the National Institute for Biological Standards and Control (NIBSC) have been endorsed as the global standards for use in laboratory tests by the World Health Organisation (WHO) Expert Committee on Biological Standardisation and are now available to the scientific community.

18 September 2015 | New polio research published

NIBSC scientists have published new research that describes a man from the UK who has been chronically infected with a virus type present in the Sabin Oral Poliovirus Vaccine and has continued to excrete the virus for the last 28 years.

7 September 2015 | NIBSC announces the appointment of a new director

NIBSC has appointed a new director, following the announcement of the forthcoming retirement of current Director Dr Stephen Inglis who has led the institute for the past 14 years.

20 August 2015 | NIBSC develops new CE-marked virus triplex

NIBSC are pleased to announce the availability of a very low positive triplex reagent (NIBSC Code 14/198) for NAT assays containing hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus-1 (HIV-1).

19 August 2015 | Launch of £10m collaborative research project to improve tools available to evaluate seasonal Influenza vaccines

The new £10m collaborative research initiative, FLUCOP, will provide new and improved tools to better evaluate how effective the immune response to the seasonal influenza vaccine is.

19 August 2015 | New international consensus on pluripotent stem cells as starting materials

The International Stem Cell Banking Initiative, coordinated by the UK Stem Cell Bank at NIBSC, is a consortium of stem cell banks, leading stem cell biologists, regulators and other expert bodies from 24 countries.

11 February 2015 | NIBSC experts at paediatric typhoid vaccine workshop

NIBSC played an important role in a recent meeting to discuss World Health Organisation (WHO) guidelines on the quality, safety and efficacy of typhoid conjugate vaccines.

14 January 2015 | New and replacement WHO international standards available

The WHO Expert Committee for Biological Standardisation met from 13 to 17 October 2014 and reviewed dossiers for proposed new and replacement international standards, reference reagents and panels.

28 November 2014 | OCABR batch release certificates

As part of the Institute’s commitment to continual improvement, NIBSC is delighted to announce that we be offering manufacturers the option to receive your OCABR certificates electronically from spring 2015. This means that your certificates will arrive even more quickly. Whilst feedback from manufacturers suggests that this will be very popular, you will have the option to continue to receive paper certificates by post if you wish.

30 September 2014 | NIBSC signs agreement with UCL

A Memorandum of Understanding has been signed between the National Institute for Biological Standards and Control and University College London (UCL). The memorandum recognises the tremendous promise of gene therapy, stem cell therapy and tissue engineering in preventing and treating illness, restoring health and saving lives.

8 April 2014 | Scientific Review of NIBSC chaired by Professor Sir Patrick Sissons published

In November 2013, an independent scientific review of the National Institute for Biological Standards and Control (NIBSC) was carried out by a review panel chaired by Professor Sir Patrick Sissons of University of Cambridge. The report has now been published.

20 February 2014 | NIBSC contributes to global flu vaccination effort

The World Health Organization (WHO) announced this morning the recommended composition of influenza vaccines for the upcoming northern hemisphere influenza season 2014-15.

20 February 2014 | New result reporting software

NIBSC has developed result reporting software(RRS) to enable data monitoring of serology QC reagents.

25 Nov 2013 | NIBSC joins European partnership in the development of a universal flu vaccine

25 Nov 2013 | Press release: New collaboration in fight against poverty related diseases

The National Institute for Biological Standards and Control (NIBSC), a centre of the Medicines and Healthcare products Regulatory Agency (MHRA), today announced it is coordinating a European project to speed up the development of ways to combat a number of poverty related diseases.

NIBSC polio vaccine nOPV2 recommended for wider use

10 January 2022 | Our First WHO International Standard (IS) for Harmonizing the Biological Activity of Bevacizumab

Our leading scientist, Dr Haiyan Jia, has recently published a paper on our first WHO International Standard for Harmonizing the Biological Activity of Bevacizumab

1 Apr 2013 | NIBSC merges with the MHRA

The National Institute for Biological Standards and Control (NIBSC), previously part of the Health Protection Agency (HPA), is now a new centre of the Medicines and Healthcare Products Regulatory Agency alongside the Clinical Practice Research Datalink (CPRD).

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NIBSC polio vaccine nOPV2 recommended for wider use