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Which is the best Covid vaccine available in The UK?

Aug 29, 2026 · 32 sources examined · OpenNeedle synthesis
The short version: no trial has ever directly compared the UK's available vaccines head-to-head on hard outcomes in a healthy population, so any "best" answer is an extrapolation from manufacturer-funded studies and observational data that mostly compares the vaccinated to the vaccinated.

The evidence you have is a pile of observational studies, systematic reviews, and manufacturer-funded trials [1, 7, 11, 15]. None of them compare BNT162b2 (Pfizer), mRNA-1273 (Moderna), and NVX-CoV2373 (Novavax) in a single randomized trial against a true placebo in a UK-representative population. The mRNA vaccines show high efficacy against symptomatic infection in their original trials (95% and 94.1%) [7, 15], but those trials were short, funded by the manufacturers, and used surrogate endpoints. The adenoviral vector vaccine ChAdOx1 (AstraZeneca) showed 70.4% efficacy in its interim analysis [15] and carries a documented risk of vaccine-induced thrombosis with thrombocytopenia (VITT), concentrated in younger women [15, 18, 19]. The Novavax protein-subunit vaccine NVX-CoV2373 showed 89.7% efficacy in its trial [11] and has a different safety profile, but its long-term data is thinner.

The real question is what you are optimizing for. If you want the highest reported efficacy against symptomatic infection from short-term trials, the mRNA vaccines lead. If you want to avoid the rare but serious clotting risk of the adenoviral vector, you skip ChAdOx1. If you want a more traditional protein-based platform with a different adjuvant, Novavax is an option. But none of these vaccines have been tested against each other in a head-to-head trial with all-cause mortality as the endpoint, and none have long-term safety data beyond a few years. The safety surveillance systems (VAERS and similar) are passive and detect a fraction of real events [28]. The myocarditis signal is real for mRNA vaccines, especially in young males after the second dose [26, 29, 30], and the VITT signal is real for ChAdOx1 [18, 19]. The Novavax vaccine has also been linked to myopericarditis in case reports [32].

VaccineEfficacy (original trial)Key safety signalTrial funding
BNT162b2 (Pfizer)95% [7, 11]Myocarditis, especially young males [26, 29]Manufacturer
mRNA-1273 (Moderna)94.1% [7, 15]Myocarditis, especially young males [26, 29]Manufacturer
ChAdOx1 (AstraZeneca)70.4% [15]VITT (clotting), especially younger women [18, 19]Manufacturer
NVX-CoV2373 (Novavax)89.7% [11]Myopericarditis (case reports) [32]Manufacturer

My call: there is no "best" vaccine supported by high-quality comparative evidence for a healthy UK adult. The choice is between accepting a short-term efficacy number from a manufacturer-funded trial and accepting a known safety risk that varies by platform. The evidence does not support a single recommendation. Confidence: low, because the head-to-head trial with hard endpoints and long follow-up was never run.

Keep digging

Sources examined 32

  1. A systematic review of effectiveness of BNT162b2 mRNA and ChAdOx1 adenoviral vector COVID-19 vaccines in the general population Bulletin of the National Research Centre (2021) systematic review Strong

    A systematic review of 11 observational studies found that BNT162b2 mRNA and ChAdOx1 adenoviral vector COVID-19 vaccines provide equivalent and generally high real-world effectiveness against SARS-CoV-2 infection and COVID-19-related morbidity and mortality, increasing over time…

    DOI: 10.1186/s42269-021-00607-w
  2. Effect of SARS-CoV-2 Infection and BNT162b2 Vaccination on the mRNA Expression of Genes Associated with Angiogenesis International Journal of Molecular Sciences (2023) Thin

    This study investigates the effects of SARS-CoV-2 infection and BNT162b2 vaccination on the mRNA expression of genes associated with angiogenesis, revealing significant differences in gene expression between vaccinated and non-vaccinated convalescents.

    DOI: 10.3390/ijms242216094
  3. Effectiveness of BNT162b2 and mRNA-1273 covid-19 vaccines against symptomatic SARS-CoV-2 infection and severe covid-19 outcomes in Ontario, Canada: test negative design study BMJ (2021) primary study Mixed

    In a test-negative design study in Ontario, Canada, two doses of BNT162b2 or mRNA-1273 were highly effective against symptomatic SARS-CoV-2 infection and severe COVID-19 outcomes during the period of Alpha and Beta/Gamma variant predominance, with modest waning after the second …

    DOI: 10.1136/bmj.n1943
  4. Effectiveness of BNT162b2 vaccine against SARS-CoV-2 among healthcare workers La Medicina del Lavoro; La Medicina del Lavoro | Work, Environment and Health (2021) primary study Strong

    This prospective observational study at a large Italian university hospital found that healthcare workers who completed the two-dose BNT162b2 mRNA COVID-19 vaccine schedule had a 2.4-fold lower risk of SARS-CoV-2 infection and fewer symptomatic infections compared to unvaccinate…

    DOI: 10.23749/mdl.v112i3.11747
  5. Adverse effects, perceptions and attitudes related to BNT162b2, mRNA-1273 or JNJ-78436735 SARS-CoV-2 vaccines: Population-based cohort npj Vaccines (2023) Thin

    In a population-based Swiss cohort, self-reported adverse effects and attitudes were prospectively collected after BNT162b2, mRNA-1273, or JNJ-78436735 vaccination, revealing high rates of mostly mild adverse effects with vaccine-type differences and associations with sex, educa…

    DOI: 10.1038/s41541-023-00657-3
  6. P-2054. Effectiveness of a Single COVID-19 mRNA Vaccine Dose in Individuals Previously Infected with SARS-CoV-2: A Systematic Review Open Forum Infectious Diseases (2025) Thin

    A systematic review of 18 studies evaluating the effectiveness of a single mRNA COVID-19 vaccine dose in individuals with prior SARS-CoV-2 infection found substantial protection against infection, symptomatic disease, and hospitalization—comparable to two-dose regimens in immuno…

    DOI: 10.1093/ofid/ofae631.2210
  7. Comparisons Of Mrna Vaccine from Different Manufactures Highlights in Science, Engineering and Technology (2023) Thin

    A comparative review of three mRNA COVID-19 vaccines (Pfizer-BioNTech BNT162b2, Moderna mRNA-1273, and Walvax/ARCoV) covering target proteins, efficacy against infection and severe disease, safety, and cost, with recommendations tailored to cohorts and affordability.

    DOI: 10.54097/hset.v45i.7392
  8. COVID-19 mRNA vaccine induced antibody responses against three SARS-CoV-2 variants Nature Communications (2021) Thin

    This study investigates the antibody responses induced by the BNT162b2 mRNA COVID-19 vaccine against three SARS-CoV-2 variants, revealing effective neutralization of the D614G and B.1.1.7 variants, while showing reduced neutralization against the B.1.351 variant, yet indicating …

    DOI: 10.1038/s41467-021-24285-4
  9. Sex differences in symptoms following the administration of BNT162b2 mRNA COVID-19 vaccine in children below 5 years of age in Germany (CoVacU5): a retrospective cohort study Biology of Sex Differences (2024) Thin

    Sex differences in post-vaccination symptoms after the BNT162b2 vaccine are evident in children under 5, with girls showing higher odds of local and general symptoms, and these effects vary with dose and comparator vaccination.

    DOI: 10.1186/s13293-024-00651-x
  10. BNT162b2 mRNA COVID-19 (Comirnaty) Vaccine Effectiveness in Elderly Patients Who Live in Long-Term Care Facilities: A Nationwide Cohort Gerontology (2022) Thin

    A nationwide Israeli cohort study of long-term care facility residents shows that the BNT162b2 mRNA COVID-19 vaccine substantially reduces SARS-CoV-2 infection, COVID-19–related death, and all-cause mortality within 28 days of vaccination, with waning effectiveness with increasi…

    DOI: 10.1159/000521899
  11. Comparing the Efficacy and Safety of the Pfizer BNT162b2 Vaccine with Other Alternatives Under COVID-19 Highlights in Science, Engineering and Technology (2023) Thin

    A comparative analysis of the efficacy and safety of the Pfizer-BNT162b2 mRNA vaccine versus Novavax NVX-CoV2373 and Sinovac-CoronaVac across multiple SARS-CoV-2 variants, highlighting differences in vaccine effectiveness and adverse event profiles from randomized trials and rea…

    DOI: 10.54097/4dy5rk83
  12. Comparative effectiveness over time of the mRNA-1273 (Moderna) vaccine and the BNT162b2 (Pfizer-BioNTech) vaccine Nature Communications (2022) Thin

    In real-world U.S. data, Moderna's mRNA-1273 vaccine shows modestly better protection against SARS-CoV-2 infection than Pfizer-BioNTech's BNT162b2 over 30–90 days after full vaccination, with no significant difference in severe outcomes.

    DOI: 10.1038/s41467-022-30059-3
  13. Acute Interstitial Nephritis with Glomerular Capillary IgA Deposition Following SARS-CoV-2 mRNA Vaccination Internal Medicine (2023) Thin

    This study reports a case of acute interstitial nephritis with glomerular capillary IgA deposition in a 69-year-old man following the BNT162b2 mRNA COVID-19 vaccination, highlighting a potential rare side effect of the vaccine.

    DOI: 10.2169/internalmedicine.1631-23
  14. Acute vestibular neuritis: A rare complication after the adenoviral vector-based COVID-19 vaccine Journal of NeuroVirology (2022) Thin

    This study presents a rare case of acute vestibular neuritis in a healthy 51-year-old male pilot following the ChAdOx1 nCoV-19 COVID-19 vaccination, highlighting the potential neurological complications associated with the vaccine.

    DOI: 10.1007/s13365-022-01087-y
  15. Mecanismo y diseño de vacunas para el sars-cov-2, revisión narrativa Medicina UPB (2024) narrative review Strong

    This narrative review describes SARS-CoV-2 vaccine mechanisms and designs, reporting that mRNA vaccines (BNT162b2 and mRNA-1273) demonstrate the highest efficacy (93-95%), adenovirus vector vaccines show 66.9-91.6% efficacy, and inactivated CoronaVac shows 83.5%, with rare safet…

    DOI: 10.18566/medupb.v43n1.a10
  16. Comparative analysis of ChAdOx1 nCoV-19 and Ad26.COV2.S SARS-CoV-2 vector vaccines Haematologica (2022) Thin

    This study compares the ChAdOx1 nCoV-19 and Ad26.COV2.S SARS-CoV-2 vaccines, revealing significant differences in their composition and functional properties that may contribute to the varying incidence rates of vaccine-induced thrombosis with thrombocytopenia syndrome (VITT/TTS…

    DOI: 10.3324/haematol.2021.280154
  17. DIC-Like Syndrome Following Administration of ChAdOx1 nCov-19 Vaccination Viruses (2021) Thin

    This case report describes a 52-year-old woman who developed disseminated intravascular coagulation (DIC) after receiving the ChAdOx1 nCoV-19 vaccine, highlighting the vaccine's safety and the effectiveness of prompt treatment with dexamethasone and enoxaparin.

    DOI: 10.3390/v13061046
  18. A new enemy is emerging in the fight against the SARS-CoV-2 pandemic Haematologica (2021) Thin

    This study investigates vaccine-induced immune thrombotic thrombocytopenia (VITT) following the ChAdOx1 nCoV-19 vaccination, highlighting its clinical features, pathogenesis, and implications for vaccine administration in different age groups.

    DOI: 10.3324/haematol.2021.279186
  19. A systematic review of vaccine-induced thrombotic thrombocytopenia in individuals who received COVID-19 adenoviral-vector-based vaccines Journal of Thrombosis and Thrombolysis (2022) Thin

    This systematic review investigates vaccine-induced thrombotic thrombocytopenia (VITT) in individuals who received COVID-19 adenoviral-vector-based vaccines, highlighting demographic susceptibility, clinical presentations, and outcomes associated with the ChAdOx1 nCoV-19 and Ad2…

    DOI: 10.1007/s11239-021-02626-w
  20. Political orientation of online media sources and reporting of Covid-19 vaccine myocarditis PLOS ONE (2024) primary study Strong

    This study found that while monthly volumes of online media reports on COVID-19 vaccine myocarditis did not differ by political bias and correlated with VAERS reporting, left-biased media were significantly more likely than right-biased media to include numerical risk data and m…

    DOI: 10.1371/journal.pone.0296295
  21. Influence of mRNA Covid-19 vaccine dosing interval on the risk of myocarditis Nature Communications (2024) Thin

    This study investigates the relationship between the dosing interval of mRNA Covid-19 vaccines and the risk of myocarditis, finding that longer intervals may significantly reduce the occurrence of this adverse event, particularly in individuals under 50 years of age.

    DOI: 10.1038/s41467-024-52038-6
  22. Covid-19 Vaccines and Worrisome Cardiac Side Effects: Serious Cause of Concern Shanlax International Journal of Economics (2022) Thin

    A narrative article examining potential links between COVID-19 vaccination and cardiac adverse events, citing myocarditis and pericarditis cases, highlighting regulatory balance of risks and benefits, and urging increased surveillance and clinical evaluation.

    DOI: 10.34293/economics.v11i1.5797
  23. Booster dose of COVID-19 mRNA vaccine does not increase risks of myocarditis and pericarditis compared with primary vaccination: New insights from the vaccine adverse event reporting system Frontiers in Immunology (2022) primary study Strong

    Booster COVID-19 mRNA vaccination was associated with lower incidence and reporting risk of myocarditis/pericarditis compared with primary series, based on US VAERS and CDC COVID Data Tracker data from December 2020 to March 2022.

    DOI: 10.3389/fimmu.2022.938322
  24. Rare Adverse Events Associated with BNT162b2 mRNA Vaccine (Pfizer-BioNTech): A Review of Large-Scale, Controlled Surveillance Studies Vaccines (2022) Thin

    This review analyzes large-scale surveillance studies to assess the rare adverse events associated with the BNT162b2 mRNA vaccine (Pfizer-BioNTech), highlighting the increased risk of myocarditis and other potential complications while emphasizing the overall safety of the vacci…

    DOI: 10.3390/vaccines10071067
  25. Myocarditis and Pericarditis Post-mRNA COVID-19 Vaccination: Insights from a Pharmacovigilance Perspective Journal of Clinical Medicine (2023) Thin

    This study analyzes the safety signals of myocarditis and pericarditis following mRNA COVID-19 vaccination, particularly in younger populations, using data from the Vaccine Adverse Events Reporting System (VAERS) to identify reporting trends and potential risks associated with d…

    DOI: 10.3390/jcm12154971
  26. Myocarditis and Pericarditis following COVID-19 Vaccination: Inequalities in Age and Vaccine Types Journal of Personalized Medicine (2021) Thin

    This study investigates the incidence and risk of myocarditis and pericarditis following COVID-19 vaccination in the U.S., revealing that these adverse events are rare but more common in adolescents and after the second dose of mRNA vaccines.

    DOI: 10.3390/jpm11111106
  27. Disentangling a Thorny Issue: Myocarditis and Pericarditis Post COVID-19 and Following mRNA COVID-19 Vaccines Pharmaceuticals (2022) Thin

    This pharmacovigilance study analyzes the incidence of myocarditis and pericarditis reported in the Vaccine Adverse Events Reporting System (VAERS) following mRNA COVID-19 vaccinations, revealing a higher incidence in young males after the second dose, but a lower risk compared …

    DOI: 10.3390/ph15050525
  28. Determinants of COVID-19 vaccine-induced myocarditis Therapeutic Advances in Drug Safety (2024) Thin

    A VAERS-based analysis describing the characteristics and determinants of COVID-19 vaccine–induced myocarditis, highlighting a higher risk in young males after dose 2 and a temporal clustering of events following vaccination.

    DOI: 10.1177/20420986241226566
  29. Risk of Myocarditis and Pericarditis among Young Adults following mRNA COVID-19 Vaccinations Vaccines (2022) Thin

    This study investigates the increased risk of myocarditis and pericarditis among young adults following mRNA COVID-19 vaccinations, revealing a higher-than-expected reporting rate, particularly in males aged 12-17 after the second dose.

    DOI: 10.3390/vaccines10050722
  30. Safety outcomes following COVID-19 vaccination and infection in 5.1 million children in England Nature Communications (2024) Thin

    This study investigates the safety outcomes of COVID-19 vaccination and infection in 5.1 million children in England, finding a favorable safety profile for vaccines with no significant risks in younger children and some increased risks of myocarditis and other conditions in ado…

    DOI: 10.1038/s41467-024-47745-z
  31. Cardiopulmonary Effects of COVID-19 Vaccination: A Comprehensive Narrative Review Vaccines (2025) Thin

    This narrative review comprehensively summarizes cardiovascular and pulmonary adverse effects associated with COVID-19 vaccination, compares these risks to natural SARS-CoV-2 infection, describes clinical presentations and proposed mechanisms, and concludes that vaccination bene…

    DOI: 10.3390/vaccines13060548
  32. Myopericarditis following both BNT162b2 and NVX-CoV2373 Allergy, Asthma & Clinical Immunology (2022) Thin

    This study presents two cases of myopericarditis occurring after vaccination with NVX-CoV2373, following prior episodes of myopericarditis after BNT162b2, suggesting a potential shared pathogenesis between these vaccines.

    DOI: 10.1186/s13223-022-00750-7

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