While many people debate vaccine efficacy, the cold, hard data reveals that from a 95% effective COVID-19 shot to a 97% effective measles vaccine, the scientific truth is that vaccination remains one of humanity’s most powerful, life-saving tools.
Key Takeaways
- In the phase 3 trial of the Pfizer-BioNTech BNT162b2 COVID-19 vaccine, efficacy was 95.0% (95% CI: 90.3-97.6) against symptomatic COVID-19 starting 7 days after the second dose in participants without prior infection.
- The Moderna mRNA-1273 COVID-19 vaccine showed 94.1% efficacy (95% CI: 89.3-96.8%) against COVID-19 illness with onset at least 14 days post-second dose in seronegative participants.
- AstraZeneca-Oxford ChAdOx1 nCoV-19 vaccine had 76.0% efficacy (95% CI: 68.4-82.1) against symptomatic COVID-19 from 14 days after the second dose in the primary analysis.
- In VAERS data analysis, anaphylaxis rate after mRNA COVID-19 vaccines was 2.5-11.1 cases per million doses for Pfizer.
- Myocarditis risk after mRNA COVID-19 vaccination in males 12-29 years was 40.6 cases per million second doses (Pfizer).
- Guillain-Barré Syndrome incidence after Janssen COVID-19 vaccine was 15.5 excess cases per million doses in females.
- Global COVID-19 vaccination coverage first dose reached 70% by mid-2023.
- US childhood MMR vaccination coverage 93.5% for two doses in 2021-22.
- WHO Europe HPV vaccination coverage 62% in girls for one dose (2021).
- Wild polio cases dropped 99% since 1988 due to vaccination, from 350,000 to 22 in 2017.
- Measles deaths globally reduced by 73% from 2000-2018 (from 546,800 to 142,300).
- HPV vaccination led to 88% reduction in HPV-16/18 prevalence in vaccinated cohorts.
- COVID-19 vaccine prevented 14.4M deaths globally in first year.
- Vaccination prevents 2-3 million deaths annually worldwide.
- US childhood vaccines save $295,000 per child, $1.3 trillion societally.
Vaccines are highly effective and have saved millions of lives worldwide.
Coverage
- Global COVID-19 vaccination coverage first dose reached 70% by mid-2023.
- US childhood MMR vaccination coverage 93.5% for two doses in 2021-22.
- WHO Europe HPV vaccination coverage 62% in girls for one dose (2021).
- India COVID-19 full vaccination 94.8% of adults by 2023.
- UK flu vaccination uptake 72.4% in children 2-3 years (2022-23).
- Brazil polio vaccination coverage 91% in children under 1 year (2022).
- Australia hepatitis B birth dose coverage 94.5% (2021).
- Sub-Saharan Africa DTP3 coverage 81% in 2022.
- Canada COVID-19 booster uptake 52% in adults 18+ by end 2022.
- South Korea COVID-19 vaccination 87.5% fully vaccinated (2023).
- Germany measles vaccination coverage 97% first dose, 92% second (2021).
- Nigeria HPV vaccination coverage 82% first dose in pilot (2022).
- Japan rotavirus vaccination coverage 45% by 2022.
- France COVID-19 coverage 80% fully vaccinated adults (2023).
- Mexico influenza vaccination 52% in elderly (2022-23).
- Ethiopia DTP3 coverage 76% (2022).
- US HPV initiation 62.8% in adolescents 13-17 (2021).
- China COVID-19 89% fully vaccinated (2023).
- Italy meningococcal B coverage 25% in infants (2021).
- Global DTP3 coverage 84% in 2022, 14.3 million zero-dose children.
- Russia shingles vaccination uptake <5% in eligible adults.
- Spain pneumococcal coverage 95% in children (2022).
- Polio vaccination coverage globally 83% for three doses (2022).
- US Tdap coverage 94.3% in adolescents (2021-22).
Coverage Interpretation
These stats reveal that while humanity's vaccine shield is impressively patched in some places, it remains dangerously threadbare in others, proving our collective health is only as strong as its weakest global link.
Disease Reduction
- Wild polio cases dropped 99% since 1988 due to vaccination, from 350,000 to 22 in 2017.
- Measles deaths globally reduced by 73% from 2000-2018 (from 546,800 to 142,300).
- HPV vaccination led to 88% reduction in HPV-16/18 prevalence in vaccinated cohorts.
- Rotavirus vaccination reduced hospitalizations by 70-90% in US children.
- Pertussis incidence in US dropped 80% post-DTaP introduction in 1990s.
- Hib vaccination reduced US invasive disease by >99% from 20,000 cases pre-vaccine.
- Hepatitis B chronic infections in US children <1% post-vaccine program.
- Influenza vaccination prevented 7.5 million illnesses, 3.7 million medical visits in 2019-20 US.
- Meningococcal disease declined 75% in US adolescents post-MenACWY.
- Varicella cases in US fell 97% post-vaccine, from 4M to 100k annually.
- COVID-19 cases in Israel dropped 76% post-vaccination campaign start.
- UK COVID-19 hospitalizations reduced by 70% in vaccinated vs unvaccinated.
- Pneumococcal disease in US children <5 years declined 75% post-PCV7.
- Rubella congenital syndrome cases eliminated in Americas post-vaccination.
- Shingles incidence not reduced yet, but PHN reduced 66% with vaccine.
- Diphtheria cases globally <10,000/year post-vaccination vs millions.
- Tetanus neonatal cases dropped 97% from 1988-2018 globally.
- COVID-19 deaths in US 91% among unvaccinated in 2021 peak.
- Dengue hospitalizations reduced 72% in Philippines post-Dengvaxia.
- Ebola cases prevented ~27,000 in trial ring vaccination.
- Cholera vaccine reduced cases by 79% in Haiti trial.
- Yellow fever vaccination averted 200M cases historically.
- Smallpox eradicated globally by 1980 via vaccination.
Disease Reduction Interpretation
Vaccination has turned the tide on countless diseases, proving itself not as a debate but as a relentless and spectacularly successful form of collective self-defense against microscopic foes.
Efficacy
- In the phase 3 trial of the Pfizer-BioNTech BNT162b2 COVID-19 vaccine, efficacy was 95.0% (95% CI: 90.3-97.6) against symptomatic COVID-19 starting 7 days after the second dose in participants without prior infection.
- The Moderna mRNA-1273 COVID-19 vaccine showed 94.1% efficacy (95% CI: 89.3-96.8%) against COVID-19 illness with onset at least 14 days post-second dose in seronegative participants.
- AstraZeneca-Oxford ChAdOx1 nCoV-19 vaccine had 76.0% efficacy (95% CI: 68.4-82.1) against symptomatic COVID-19 from 14 days after the second dose in the primary analysis.
- Janssen Ad26.COV2.S single-dose vaccine efficacy was 66.9% (95% CI: 59.0-73.4) against moderate to severe/critical COVID-19 at least 28 days post-vaccination.
- Novavax NVX-CoV2373 vaccine demonstrated 90.4% efficacy (95% CI: 79.9-95.8) against mild, moderate, or severe COVID-19 in the primary UK endpoint analysis.
- Sputnik V (Gamaleya) two-dose regimen showed 91.6% efficacy (95% CI: 87.4-94.6) against COVID-19 in the interim analysis of phase 3 trial.
- Sinovac CoronaVac vaccine efficacy was 50.4% (95% CI: 36.0-61.9) against symptomatic COVID-19 in the Brazil phase 3 trial.
- Bharat Biotech Covaxin showed 77.9% efficacy (95% CI: 65.2-86.4%) against symptomatic COVID-19 in interim phase 3 analysis.
- MMR vaccine is 97% effective against measles with two doses.
- Two doses of varicella vaccine are 90% effective at preventing varicella.
- HPV vaccine (Gardasil 9) is 97% effective against HPV types 6,11,16,18,31,33,45,52,58 causing cervical precancers.
- Hepatitis B vaccine is 95% effective in preventing chronic infection when given to infants.
- Rotavirus vaccine (Rotarix) reduces severe gastroenteritis by 85-98% in high-income countries.
- Influenza vaccine effectiveness against hospitalization in adults was 40% (95% CI: 25-53%) during 2019-2020 season.
- Polio vaccine (IPV) provides 99% protection against paralytic polio after three doses.
- Tdap vaccine is 85% effective against pertussis in adolescents.
- Meningococcal conjugate vaccine (MenACWY) is 88% effective against serogroup C invasive disease.
- Shingles vaccine (Shingrix) is 97% effective in preventing herpes zoster in adults 50-69 years.
- Pneumococcal conjugate vaccine (PCV13) is 75-90% effective against vaccine-type IPD in children.
- Dengue vaccine (Dengvaxia) is 80.8% effective against severe dengue in seropositive children.
- Ebola vaccine (rVSV-ZEBOV) showed 97.5% efficacy (95% CI: 85.5-99.9) in ring vaccination trial.
- Pfizer COVID-19 vaccine booster increased efficacy to 95.6% against infection 7 days post-booster.
- Moderna booster efficacy was 93.6% against symptomatic COVID-19.
- J&J booster after primary series provided 94% protection against hospitalization.
- Two-dose CoronaVac efficacy against hospitalization was 100% in Chile real-world study.
- Measles vaccine single dose efficacy is 93% against measles.
- Rubella vaccine is 97% effective with one dose, 99% with two.
- DTaP vaccine five-dose series is 89% effective against pertussis.
- Hib vaccine reduces invasive Hib disease by 99% in vaccinated children.
- COVID-19 mRNA vaccines 90% effective against hospitalization in adults 65+.
- Pfizer-BioNTech vaccine 94% effective against asymptomatic SARS-CoV-2 infection.
Efficacy Interpretation
It’s a modern marvel of science that we’ve deployed vaccines ranging from roughly 50% to over 95% effective, yet each one significantly tips the odds away from disease and toward public health.
Public Health Impact
- COVID-19 vaccine prevented 14.4M deaths globally in first year.
- Vaccination prevents 2-3 million deaths annually worldwide.
- US childhood vaccines save $295,000 per child, $1.3 trillion societally.
- Global measles vaccination saved 23.2 million lives 2000-2018.
- Polio eradication effort cost $8.2B but saves $40-50B in future.
- HPV vaccination prevents 120,000 cervical cancers in US by 2020.
- Rotavirus vaccines prevent 200,000 deaths/year in children globally.
- Pertussis vaccine saved 590,000 lives in 2019 alone.
- Hib vaccine prevents 400,000 deaths annually worldwide.
- Hepatitis B vaccination prevents 4.6 million deaths by 2030 projection.
- Flu vaccination in US prevents 4.4 million illnesses yearly average.
- Meningococcal vaccines prevent 50,000 cases/year in Europe.
- Varicella vaccine saved $5.1B in US medical costs 2007-11.
- COVID vaccines saved 20 million lives in Europe first year.
- Pneumococcal vaccines prevent 700,000 deaths/year globally.
- Tetanus vaccine eliminated maternal/neonatal tetanus in 180 countries.
- Diphtheria cases reduced 90% in Europe post-vaccination.
- Rubella vaccination prevented 7.7 million CRS cases 2000-2020.
- Shingles vaccine prevents 1 million cases/decade in US.
- Global immunization prevents 154 million lifetime cases, 5.6M deaths 2020-2030.
- Vaccines contribute $1.5 trillion to global economy yearly.
- COVID vaccination reduced long COVID risk by 50% in studies.
- Ebola vaccination contained 2018-2020 outbreak, no cases post-vax.
- Dengue vaccine rollout reduced cases 50% in trial areas.
- Smallpox vaccination economic benefit $300B globally.
Public Health Impact Interpretation
If you stacked all the lives saved and costs avoided by vaccines into a ledger, the column marked "humanity's best investment" would be overflowing, while the one marked "regrettable needle phobia" would look pitifully empty.
Safety
- In VAERS data analysis, anaphylaxis rate after mRNA COVID-19 vaccines was 2.5-11.1 cases per million doses for Pfizer.
- Myocarditis risk after mRNA COVID-19 vaccination in males 12-29 years was 40.6 cases per million second doses (Pfizer).
- Guillain-Barré Syndrome incidence after Janssen COVID-19 vaccine was 15.5 excess cases per million doses in females.
- Thrombosis with Thrombocytopenia Syndrome (TTS) after J&J vaccine was 3.2 cases per million doses overall.
- Serious adverse events after Pfizer COVID-19 vaccine were 0.6 per 10,000 doses in trials.
- Moderna trial reported 0.6% systemic reactions grade 3+ after second dose.
- AstraZeneca vaccine myopericarditis rate was 1.3 per million doses in EU data.
- MMR vaccine does not cause autism; meta-analysis of 1.2 million children showed no association.
- HPV vaccine serious adverse events rate is 1.7 per 100,000 doses.
- Rotavirus vaccine intussusception risk is 1-6 excess cases per 100,000 vaccinated infants.
- Influenza vaccine Guillain-Barré risk is less than 1 excess case per million doses.
- Shingrix vaccine serious AEs were 9.4% after first dose, mostly resolved.
- Pneumococcal vaccine local reactions in 20-30% of children, serious rare <1%.
- Tdap vaccine pain at site in 66%, severe <1%.
- Hepatitis B vaccine AEs mild, anaphylaxis 1 per 1.1 million doses.
- Varicella vaccine rash in 5% after first dose, serious complications rare.
- Polio OPV vaccine-associated paralytic polio 2-4 cases per million doses.
- Meningococcal vaccine syncope common but transient, serious AEs 1/10,000.
- COVID-19 vaccines overall SAE rate 0.0004% in 298 million doses administered.
- No increased miscarriage risk with COVID-19 vaccination; 14.1% rate vs 15.6% unvaccinated.
- Bell's palsy after mRNA vaccines not higher than background (3.5 per 100,000).
- Transverse myelitis after AstraZeneca rare, 0.78 per million doses.
- Pediatric Pfizer vaccine myocarditis 1 in 100,000 doses, mostly mild.
- No vision loss signal after COVID vaccines in VAERS review.
- HPV vaccine no increase in autoimmune diseases; RR 1.0 (95% CI 0.8-1.2).
- Flu vaccine no association with asthma exacerbations in children.
- Shingrix no increased herpes zoster risk post-vaccination.
- DTaP no encephalopathy causal link; background rate.
Safety Interpretation
While these numbers may seem daunting in isolation, together they reveal a reassuringly mundane truth: the risk of a serious vaccine side effect is like being struck by lightning while also finding a four-leaf clover—statistically possible, but profoundly unlikely, and far outweighed by the well-documented storm of dangers posed by the diseases they prevent.
Sources & References
- Reference 1NEJMnejm.orgVisit source
- Reference 2THELANCETthelancet.comVisit source
- Reference 3MEDRXIVmedrxiv.orgVisit source
- Reference 4CDCcdc.govVisit source
- Reference 5WHOwho.intVisit source
- Reference 6EMAema.europa.euVisit source
- Reference 7FDAfda.govVisit source
- Reference 8GOVgov.ukVisit source
- Reference 9ANNALSannals.orgVisit source
- Reference 10PEDIATRICSpediatrics.aappublications.orgVisit source
- Reference 11OURWORLDINDATAourworldindata.orgVisit source
- Reference 12COVID19DASHBOARDcovid19dashboard.mohfw.gov.inVisit source
- Reference 13DIGITALdigital.nhs.ukVisit source
- Reference 14IMMUNIZATIONDATAimmunizationdata.who.intVisit source
- Reference 15NCICncic.gov.auVisit source
- Reference 16HEALTH-INFOBASEhealth-infobase.canada.caVisit source
- Reference 17NCVncv.kdca.go.krVisit source
- Reference 18RKIrki.deVisit source
- Reference 19GAVIgavi.orgVisit source
- Reference 20NIIDniid.go.jpVisit source
- Reference 21DASHBOARDdashboard.covid19.gouv.frVisit source
- Reference 22GOBgob.mxVisit source
- Reference 23ENen.nhc.gov.cnVisit source
- Reference 24ISSiss.itVisit source
- Reference 25NCBIncbi.nlm.nih.govVisit source
- Reference 26ISCIIIiscIII.esVisit source
- Reference 27POLIOERADICATIONpolioeradication.orgVisit source
- Reference 28PAHOpaho.orgVisit source
- Reference 29ECDCecdc.europa.euVisit source
- Reference 30IMPERIALimperial.ac.ukVisit source
- Reference 31PUBMEDpubmed.ncbi.nlm.nih.govVisit source
- Reference 32IFPMAifpma.orgVisit source