Science Brief: COVID-19 Vaccines and Vaccination
Summary of Recent Changes
- Data were added from studies published since the last update that further demonstrate currently authorized COVID-19 vaccines are effective against SARS-CoV-2 infection, symptomatic and severe disease, and hospitalization with COVID-19.
- Data were added suggesting that currently authorized mRNA vaccines provide protection against variants of concern, including the B.1.1.7 strain that is predominant in the United States.
- Data were added from studies published since the last update that further demonstrate people who are fully vaccinated with a currently authorized mRNA vaccine are protected against asymptomatic infection and, if infected, have a lower viral load than unvaccinated people.
- All COVID-19 vaccines currently authorized in the United States are effective against COVID-19, including serious outcomes like severe disease, hospitalization, and death.
- Available evidence suggests the currently authorized mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) provide protection against a variety of strains, including B.1.1.7 (originally identified in the United Kingdom) and B.1.351 (originally identified in South Africa). Other vaccines show reduced efficacy against B.1.351 but may still protect against severe disease. Continued monitoring of vaccine effectiveness against variants is needed.
- A growing body of evidence indicates that people fully vaccinated with an mRNA vaccine (Pfizer-BioNTech and Moderna) are less likely to have asymptomatic infection or to transmit SARS-CoV-2 to others. Studies are underway to learn more about the benefits of Johnson & Johnson/Janssen vaccine. However, the risk for SARS-CoV-2 infection in fully vaccinated people cannot be completely eliminated as long as there is continued community transmission of the virus.
- At this time, there are limited data on vaccine effectiveness in people who are immunocompromised. People with immunocompromising conditions, including those taking immunosuppressive medications, should discuss the need for personal protective measures after vaccination with their healthcare provider.
- This updated science brief synthesizes the scientific evidence supporting CDC’s guidance for fully vaccinated people and will continue to be updated as more information becomes available.
COVID-19 vaccination is a critical prevention measure to help end the COVID-19 pandemic. COVID-19 vaccines are now more widely accessible in the United States, and all people 12 years and older are recommended to be vaccinated against COVID-19. Three COVID-19 vaccines are currently authorized by the U.S. Food and Drug Administration (FDA) for emergency use: two mRNA vaccines (Pfizer-BioNTech, Moderna) and one viral vector vaccine (Johnson & Johnson/Janssen vaccine). People are considered fully vaccinated if they are ≥2 weeks following receipt of the second dose in a 2-dose series (mRNA vaccines), or ≥2 weeks following receipt of a single-dose vaccine (Johnson & Johnson/Janssen).*
Public health recommendations for people fully vaccinated with COVID-19 vaccines must consider the evidence, including vaccine effectiveness against symptomatic and asymptomatic COVID-19, as well as vaccine impact on SARS-CoV-2 transmission. Other individual and societal factors are also important when evaluating the benefits and potential harms of prevention measures among vaccinated individuals. The Advisory Committee on Immunization Practices and CDC routinely consider factors such as population values, acceptability, and feasibility of implementation when making vaccine recommendations.(1) These factors were also considered when developing CDC’s interim public health recommendations for fully vaccinated people.
In this scientific brief, we summarize evidence available through May 19, 2021, for the currently authorized COVID-19 vaccines (administered according to the recommended schedules) and additional considerations used to inform public health recommendations for fully vaccinated people, including:
- Vaccine efficacy and effectiveness against SARS-CoV-2 infection
- Vaccine performance against emerging SARS-CoV-2 variant viruses
- Impact of other prevention measures in the context of vaccination
Accumulating evidence indicates that fully vaccinated people without immunocompromising conditions are able to engage in most activities with very low risk of acquiring or transmitting SARS-CoV-2. The benefits of avoiding disruptions such as unnecessary quarantine and social isolation might outweigh the low residual risk of becoming ill with COVID-19, generally with mild disease, or of transmitting the virus to others.
COVID-19 vaccine efficacy and effectiveness
Vaccine efficacy refers to how well a vaccine performs in a carefully controlled clinical trial, whereas effectiveness describes its performance in real-world observational studies. Evidence demonstrates that the authorized COVID-19 vaccines are both efficacious and effective against symptomatic, laboratory-confirmed COVID-19, including severe forms of the disease. In addition, a growing body of evidence suggests that mRNA COVID-19 vaccines also reduce asymptomatic infection and transmission. Substantial reductions in SARS-CoV-2 infections (both symptomatic and asymptomatic) will reduce overall levels of disease, and therefore, viral transmission in the United States. However, investigations are ongoing to assess further the impact of COVID-19 vaccination on transmission.
Animal challenge studies
Rhesus macaque challenge studies provided the first evidence of the potential protective effects of Pfizer-BioNTech, Moderna, and Johnson & Johnson/Janssen COVID-19 vaccines against SARS-CoV-2 infection, including asymptomatic infection. Vaccinated macaques developed neutralizing antibodies that exceeded those in human convalescent sera and showed no or minimal signs of clinical disease after SARS-CoV-2 challenge.(2-4) In addition, COVID-19 vaccination prevented or limited viral replication in the upper and lower respiratory tracts, which may have implications for transmission of the virus among humans.(2-4)
Vaccine efficacy from human clinical trials
Clinical trials subsequently demonstrated the authorized COVID-19 vaccines to be efficacious against laboratory-confirmed, symptomatic COVID-19 in adults, including severe forms of the disease, with evidence for protection against asymptomatic SARS-CoV-2 infection as well (5-11) (Box). Recent trial data demonstrated 100% efficacy of the Pfizer-BioNTech vaccine against laboratory-confirmed, symptomatic COVID-19 in adolescents 12–15 years old, although this estimate was based on small numbers of cases.(12)
Box 1. Summary of vaccine efficacy estimates for authorized COVID-19 vaccines
All authorized COVID-19 vaccines demonstrated efficacy (range 65% to 95%) against symptomatic, laboratory-confirmed COVID-19 in adults ≥18 years.
- For each authorized COVID-19 vaccine, the overall efficacy was similar to the efficacy across different populations, including elderly and younger adults, in people with and without underlying health conditions, and in people representing different races and ethnicities.
- The Pfizer-BioNTech COVID-19 vaccine also demonstrated high efficacy against symptomatic, laboratory-confirmed COVID-19 in adolescents aged 12-17 years.
All authorized COVID-19 vaccines demonstrated high efficacy (≥89%) against COVID-19 severe enough to require hospitalization.
All authorized COVID-19 vaccines demonstrated high efficacy against COVID-19-associated death.
- In the clinical trials, no participants who received a COVID-19 vaccine died from COVID-19; the Moderna and Johnson & Johnson/Janssen trials among adults ≥18 years each had COVID-19 deaths in the placebo arm.
Preliminary data from the clinical trials among adults ≥18 years old suggest COVID-19 vaccination may also protect against asymptomatic infection.
- In the Moderna trial, among people who had received a first dose, the number of asymptomatic people who tested positive for SARS-CoV-2 at their second-dose appointment was approximately two-thirds lower among vaccinees than among placebo recipients (0.1% and 0.3%, respectively)
- Efficacy of Johnson & Johnson/Janssen COVID-19 vaccine against asymptomatic seroconversion was 74% in a subset of trial participants.
No trials have compared efficacy between any of the authorized vaccines in the same study population at the same time, making comparisons of efficacy difficult.
- All Phase 3 trials differed by calendar time and geography.
Real-world vaccine effectiveness
Multiple studies from the United States and other countries demonstrate that a two-dose COVID-19 vaccination series is highly effective against SARS-CoV-2 infection (including both symptomatic and asymptomatic infections) and sequelae including severe disease, hospitalization, and death. Early evidence for the Johnson & Johnson/Janssen vaccine also demonstrates effectiveness against COVID-19 in real-world conditions.
Table 1a. Effectiveness against SARS-CoV-2 infection and symptomatic disease
|United States13||General adult population||Pfizer-BioNTech or Moderna||SARS-CoV-2 infection||89%*1|
|United States14||General adult population||Pfizer-BioNTech or Moderna||SARS-CoV-2 infection||86%*2|
|United States15||General adult population||Pfizer-BioNTech or Moderna||Hospitalization||96%*1|
|United States16||Healthcare workers||Pfizer-BioNTech||SARS-CoV-2 infection||97%*2|
|United States17||Healthcare workers, first responders, and other essential and frontline workers||Pfizer-BioNTech or Moderna||SARS-CoV-2 infection||90%*2|
|United States18||Healthcare Workers||Pfizer-BioNTech||SARS-CoV-2 infection||96%*1|
|United States(19)||Healthcare workers||Pfizer-BioNTech or Moderna||Symptomatic disease||94%*1|
|United States(20)||Healthcare workers and residents in a skilled nursing facility||Pfizer-BioNTech||Residents: symptomatic disease||87%*2|
|Healthcare workers: symptomatic disease||87%*2|
|United States21||Hospitalized adults ≥65 years old||Pfizer-BioNTech or Moderna||Hospitalization||94%*2|
|United States22||Health system members ≥18 years old||Johnson & Johnson/Janssen||SARS-CoV-2 infection||77%*2|
|United Kingdom23||Healthcare workers||Pfizer-BioNTech or AstraZeneca||SARS-CoV-2 infection||90%*2|
|United Kingdom24||Healthcare workers||Pfizer-BioNTech||SARS-CoV-2 infection||86%*1|
|United Kingdom (Scotland)26||Healthcare workers||Pfizer-BioNTech or AstraZeneca||SARS-CoV-2 infection||92%*2|
|United Kingdom27||Adults aged ≥ 80 years, including those with multiple underlying conditions||Pfizer-BioNTech||Symptomatic disease||85%*2|
|Israel28||HMO members >16 years old||Pfizer-BioNTech||SARS-CoV-2 infection||89%*1|
|Israel29||Health system members||Pfizer-BioNTech||<60 years old: SARS-CoV-2 infection||93%*2|
|≥60 years old: SARS-CoV-2 infection||92%*2|
|Israel30||General adult population||Pfizer-BioNTech||SARS-CoV-2 infection||92%*1|
|Israel31||General population ≥16 years||Pfizer-BioNTech||SARS-CoV-2 infection||93%*1|
|Israel32||General population ≥16 years||Pfizer-BioNTech||Symptomatic disease||>97%*1|
|Israel33||Healthcare workers||Pfizer-BioNTech||Symptomatic disease||>97%*1|
|Israel34||Healthcare workers||Pfizer-BioNTech||Symptomatic disease||>90%*3|
|Italy35||Healthcare workers||Pfizer-BioNTech||Symptomatic disease||>95%*1|
|Denmark36||Long term care facility residents||Pfizer-BioNTech||SARS-CoV-2 infection||64%*1|
|Long term care facility staff||Pfizer-BioNTech||SARS-CoV-2 infection||90%*1|
|Sweden37||General adult population||Pfizer-BioNTech||SARS-CoV-2 infection||86%*1|
*Only studies including estimates of vaccine effectiveness ≥7 days following a completed vaccination series are included here. Studies examining multiple vaccines for which a single estimate of vaccine effectiveness is reported did not assess vaccine effectiveness by product type.
1≥7 days after second dose
2≥14 days after second dose
3≥11 days after second dose
In addition to the studies listed in Table 1a., further evidence of the impact of vaccination with Pfizer-BioNTech and Moderna COVID-19 vaccine has been demonstrated among healthcare workers, with major reductions in SARS-CoV-2 infections among those receiving two doses of COVID-19 vaccine even when community transmission was increasing.(38-40)
Table 1b. Effectiveness of COVID-19 Vaccination Against Asymptomatic SARS-CoV-2 Infection
|United States49||General adult population||Pfizer-BioNTech or Moderna||Asymptomatic infection||80%*1|
|United States18||Healthcare workers||Pfizer-BioNTech||Asymptomatic infection||90%*2|
|Israel32||General adult population||Pfizer-BioNTech||Asymptomatic infection||92%*2|
|Israel33||Healthcare workers||Pfizer-BioNTech or AstraZeneca||Asymptomatic infection||86%*2|
|Israel34||Healthcare workers||Pfizer-BioNTech||Asymptomatic infection||65%*3|
1≥0 days after second dose
2≥7 days after second dose
3≥11 days after second dose
Data from multiple studies in different countries suggest that people vaccinated with Pfizer-BioNTech COVID-19 vaccine who develop COVID-19 have a lower viral load than unvaccinated people.(50-54) This observation may indicate reduced transmissibility, as viral load has been identified as a key driver of transmission(55). Two studies from the United Kingdom found significantly reduced likelihood of transmission to household contacts from people infected with SARS-CoV-2 who were previously vaccinated for COVID-19.(26, 56)
Vaccine effectiveness in immunosuppressed people
Evidence of reduced antibody response to or reduced immunogenicity of COVID-19 mRNA vaccination has been observed in the following groups: people taking certain immunosuppressive medications like rituximab (42, 43, 45, 57) or mycophenolate (45, 58-60), people with hematologic cancers (44, 47), and hemodialysis patients (46). At this time, data on vaccine protection in people who are immunocompromised are limited; in addition, the impact of immune suppression on COVID-19 vaccine effectiveness may vary by condition.(47, 48) Complete data on which immunocompromising conditions might affect response to COVID-19 vaccination are not available; in addition, there is no established immune correlate of protection against SARS-CoV-2 so the risk of infection in people who respond incompletely to COVID-19 vaccination cannot be quantified using immunogenicity data. People with immunocompromising conditions, including those taking immunosuppressive medications, should discuss the need for personal protective measures after vaccination with their healthcare provider.
Vaccine performance against emerging SARS-CoV-2 variant viruses
SARS-CoV-2 variants of concern (VOC: B.1.1.7, first detected in the United Kingdom; B.1.351, first detected in South Africa; P.1, first detected in Japan/Brazil; and B.1.427 and B.1.429, first detected in US-California) have emerged with mutations that alter the receptor binding domain of the spike protein (notably the N501Y mutation occurring in B.1.1.7, B.1.351 and P.1 variants, the E484K and E417T/N mutations in B.1.351 and P.1, and the L452R mutation in B.1.427 and B.1.429).(61) Similar mutations also occur in SARS-CoV-2 variants of interest (VOI: B.1.526 and B.1.526.1, first detected in US-New York; B.1.525, first detected in the United Kingdom/Nigeria; and B.1.617, B.1.617.1, B.1.617.2 and B.1.617.3, first detected in India)(61), but these variants currently have limited prevalence or expansion in the United States or other countries and still lack clear evidence of increased transmission, disease severity, or impact on available vaccines, therapeutics, or diagnostic tests.(61) Vaccine performance against emerging SARS-CoV-2 variants is an important consideration when evaluating the need for prevention measures in vaccinated people and will require continued monitoring. When evaluating risk, considering regional and local circulation of SARS-CoV-2 variants is also relevant; current data can be found on CDC’s website.
Vaccine-induced neutralizing antibody activity
Sera from mRNA COVID-19 vaccine (both Pfizer-BioNTech and Moderna) recipients have demonstrated minimal to large reductions in antibody neutralization activity against a variety of mutations.(62-106) Across studies of VOC, the greatest reductions were observed for B.1.351, followed by P.1; reductions for B.1.1.7 and B.1.427/B.1.429 were minimal. A limited number of studies were available for some VOI that demonstrated greater reductions for P.2, B.1.525, and B.1.617.1 and minimal reductions for B.1.617 and B.1.526.(67, 84, 86-88, 93-95, 100, 101) The E484K mutation alone or in combination with other mutations in the receptor binding domain has been shown to account for the majority of reduction in vaccine-induced neutralizing antibody activity for the B.1.351, P.1, and P.2 variants.(65, 67, 77, 79, 107) B.1.1.7 and B.1.526 variants with E484K mutations, which have been detected in the United Kingdom, United States, and other countries, have shown further reductions in neutralization above B.1.1.7 and B.1.526 alone, respectively.(62, 65, 81, 84, 86, 93) Two studies have shown that six months after receiving the Moderna vaccine, higher proportions of people had undetectable neutralization activity against B.1.351 and P.1 compared with the ancestral strain.(108, 109) In the absence of a biological correlate of protection, it is difficult to predict how reduced neutralizing activity may affect COVID-19 vaccine effectiveness. However, across studies, antibody neutralizing activity of sera from vaccinated people was generally higher than that observed for convalescent sera from people who have recovered from COVID-19.(65, 66, 68, 72-77, 79, 83, 104, 107)
Vaccine-induced cellular immunity
Several studies have assessed CD4+ and CD8+ T cell responses from Moderna or Pfizer vaccine recipients to the ancestral SARS-CoV-2 strain compared with the B.1.1.7, B.1.351, P.1, and B.1.427 variants; these studies observed modest or no defects in cellular immune recognition of the variants.(75, 90, 101, 110-113) Thus, cellular immunity may help limit disease severity in infections caused by variants that partially escape neutralizing antibodies. Polymorphisms in human leukocyte antigen alleles have been observed to result in variation of the T cell response to specific variants, which may impact different subpopulations differently based on higher genetic prevalence.(114-116)
Efficacy and effectiveness
A recent study from Qatar demonstrated high effectiveness after ≥14 days for the Pfizer-BioNTech vaccine against any documented infection caused by B.1.1.7 (90%) and B.1.351 (75%); importantly, the vaccine was 100% effective against severe, critical, or fatal disease, regardless of strain.(117) As described above, a growing number of studies in Israel, Europe, and the United Kingdom have also demonstrated high real-world effectiveness (>85%) of two doses of Pfizer-BioNTech COVID-19 vaccine while B.1.1.7 was prevalent.(24, 30-32, 34, 37) A study from California demonstrated 86% effectiveness among people fully vaccinated with Pfizer-BioNTech or Moderna vaccine during a time when 69% of sequenced SARS-CoV-2 isolates in the state were B.1.1.7, B.1.427, or B.1.429.(14) Clinical trial data suggest that the Johnson & Johnson/Janssen COVID-19 vaccine may have reduced overall efficacy against the B.1.351 variant. Although spike-protein-specific and seroresponse rates were similar between U.S clinical trial participants and those from Brazil and South Africa, vaccine efficacy after ≥14 days was 74% in the United States and 66% in Brazil (where ~69% of infections were due to P.2), but in South Africa (~where 95% of infections were due to B.1.351), efficacy was 52%. (8, 9) (11) Notably, Johnson & Johnson/Janssen vaccine showed good efficacy against severe or critical disease (73%–82%) across all sites. (8, 9)
Impact of prevention measures in the context of vaccination
Individual and community-level prevention measures have been shown to help reduce the spread of SARS-CoV-2. (118-123) However, there are individual and societal costs related to physical distancing, quarantine, school and business closures, and other prevention measures.(124-131)
Modeling studies suggest that adherence to prevention measures, such as wearing masks and physical distancing, continues to be important in the context of vaccine implementation.(132-140) In one study, complete relaxation of prevention measures for the entire population prior to adequate vaccination coverage (60-80% depending on the population considered) resulted in essentially no reductions in SARS-CoV-2 infections.(132) However, in the context of rapid vaccine implementation, the benefit of non-pharmaceutical interventions decreases: preliminary data from one study found prevention measures in the United States could begin to be relaxed 2-3 months after vaccination began if a rate of 3 million doses administered daily were attained.(141) Correspondingly, preliminary data suggest that increasing vaccination rates may allow for the phasing out of some prevention measures as coverage increases (138). With high vaccine effectiveness and increasing vaccination coverage, preliminary modeling studies predict that vaccinated people returning to normal activities will have minimal impact on the course of the pandemic.(141, 142)
In summary, prevention measures will continue to be important during the period of vaccine deployment. As vaccination coverage increases, phasing out prevention measures for fully vaccinated people, ideally those measures that are the most disruptive to individuals and society, will be increasingly feasible.
COVID-19 vaccines currently authorized in the United States have been shown to be efficacious and effective against SARS-CoV-2 infections, including asymptomatic infection, symptomatic disease, severe disease, and death. These findings, along with the early evidence for reduced viral load in vaccinated people who develop COVID-19, suggest that any associated transmission risk is likely to be substantially reduced in vaccinated people. While vaccine effectiveness against emerging SARS-CoV-2 variants remains under investigation, available evidence suggests that the COVID-19 vaccines presently authorized in the United States offer protection against known emerging variants.
Evidence suggests the U.S. COVID-19 vaccination program has the potential to substantially reduce the burden of disease in the United States by preventing illness in fully vaccinated people and interrupting chains of transmission. The risks of SARS-CoV-2 infection in fully vaccinated people cannot be completely eliminated where community transmission of the virus is widespread. Vaccinated people could potentially still become infected and spread the virus to others. However, in the context of rapidly increasing vaccination coverage, modeling data predict reduced benefits of non-pharmaceutical prevention measures and minimal impact on the course of the pandemic of fully vaccinated people returning to normal activities. People with compromised immune systems should discuss the need to continue using personal protective measures after vaccination with their healthcare provider. Some fully vaccinated people who are not immunocompromised may prefer to continue using prevention measures for personal comfort or because they or a member of their family are at increased risk for severe COVID-19. Taken together, the evidence supports phasing out prevention measures for fully vaccinated people as an increasingly large proportion of the United States population receives COVID-19 vaccines.
*Note: CDC guidance for fully vaccinated people can also be applied to COVID-19 vaccines that have been listed for emergency use by the World Health Organization (e.g. AstraZeneca/Oxford). This brief summarizes evidence related to vaccines authorized for emergency use in the United States.
Note: Preprints have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information.
- Lee G, Carr W, Group AE-BRW, Group AEBRW. Updated Framework for Development of Evidence-Based Recommendations by the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 2018;67(45):1271-2.
- Corbett KS, Flynn B, Foulds KE, Francica JR, Boyoglu-Barnum S, Werner AP, et al. Evaluation of the mRNA-1273 Vaccine against SARS-CoV-2 in Nonhuman Primates. N Engl J Med. 2020;383(16):1544-55.
- Mercado NB, Zahn R, Wegmann F, Loos C, Chandrashekar A, Yu J, et al. Single-shot Ad26 vaccine protects against SARS-CoV-2 in rhesus macaques. Nature. 2020;586(7830):583-8.
- Vogel AB, Kanevsky I, Che Y, Swanson KA, Muik A, Vormehr M, et al. BNT162b vaccines protect rhesus macaques from SARS-CoV-2. Nature. 2021.
- Food and Drug Administration. Pfizer-BioNTech COVID-19 Vaccine. Vaccines and Related Biological Products Advisory Committee Briefing Document – Sponsor. https://www.fda.gov/media/144246/downloadexternal icon.
- Food and Drug Administration. Moderna COVID-19 Vaccine. Vaccines and Related Biological Products Advisory Committee December 17, 2020 Meeting Briefing Document- Sponsor. https://www.fda.gov/media/144452/downloadexternal icon.
- Food and Drug Administration. Moderna COVID-19 Vaccine. Vaccines and Related Biological Products Advisory Committee December 17, 2020 Meeting Briefing Document Addendum- Sponsor. https://www.fda.gov/media/144453/downloadexternal icon.
- Food and Drug Administration. Janssen COVID-19 Vaccine. Vaccines and Related Biological Products Advisory Committee February 26, 2021 Meeting Briefing Document – Sponsor. https://www.fda.gov/media/146219/downloadexternal icon.
- Food and Drug Administration. Janssen COVID-19 Vaccine. Vaccines and Related Biological Products Advisory Committee February 26, 2021 Meeting Briefing Document Addendum – Sponsor. https://www.fda.gov/media/146218/downloadexternal icon.
- Baden LR, El Sahly HM, Essink B, Kotloff K, Frey S, Novak R, et al. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. N Engl J Med. 2021;384(5):403-16.
- Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med. 2020;383(27):2603-15.
- Food and Drug Administration. Emergency Use Authorization (EUA) Amendment for an Unapproved Product Review Memorandum. https://www.fda.gov/media/148542/downloadexternal icon.
- Pawlowski C LP, Puranik A, et. al. FDA-authorized COVID-19 vaccines are effective per real-world evidence synthesized across a multi-state health system. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.02.15.21251623v1.full.pdfpdf iconexternal icon.
- Andrejko K. PJ, Myers JF., et al. Early evidence of COVID-19 vaccine effectiveness within the general population of California. MedRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.08.21255135v1external icon.
- Vahidy FS. PL, Tano ME., et al. Real World Effectiveness of COVID-19 mRNA Vaccines against Hospitalizations and Deaths in the United States. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.21.21255873v1external icon.
- Swift MD, Breeher LE, Tande AJ, Tommaso CP, Hainy CM, Chu H, et al. Effectiveness of mRNA COVID-19 vaccines against SARS-CoV-2 infection in a cohort of healthcare personnel. Clin Infect Dis. 2021.
- Thompson MG BJ, Naleway AL, et al. Interim Estimates of Vaccine Effectiveness of BNT162b2 and mRNA-1273 COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Health Care Personnel, First Responders, and Other Essential and Frontline Workers — Eight U.S. Locations, December 2020–March 2021. MMWR Morb Mortal Wkly Rep. 2021;ePub: 29 March 2021. DOI: http://dx.doi.org/10.15585/mmwr.mm7013e3external icon.
- Tang L, Hijano DR, Gaur AH, Geiger TL, Neufeld EJ, Hoffman JM, et al. Asymptomatic and Symptomatic SARS-CoV-2 Infections After BNT162b2 Vaccination in a Routinely Screened Workforce. JAMA. 2021.
- Pilishvili T. F-DK, Farrar JL., et al. Interim Estimates of Vaccine Effectiveness of Pfizer-BioNTech and Moderna COVID-19 Vaccines Among Health Care Personnel — 33 U.S. Sites, January–March 2021. MMWR Morb Mortal Wkly Rep. 2021;https://www.cdc.gov/mmwr/volumes/70/wr/mm7020e2.htm.
- Cavanaugh AM, Fortier S, Lewis P, Arora V, Johnson M, George K, et al. COVID-19 Outbreak Associated with a SARS-CoV-2 R.1 Lineage Variant in a Skilled Nursing Facility After Vaccination Program – Kentucky, March 2021. MMWR Morb Mortal Wkly Rep. 2021;70(17):639-43.
- Tenforde MW, Olson SM, Self WH, Talbot HK, Lindsell CJ, Steingrub JS, et al. Effectiveness of Pfizer-BioNTech and Moderna Vaccines Against COVID-19 Among Hospitalized Adults Aged >/=65 Years – United States, January-March 2021. MMWR Morb Mortal Wkly Rep. 2021;70(18):674-9.
- Corchado-Garcia J. P-ZD, Hughes T., et al. Real-world effectiveness of Ad26.COV2.S adenoviral vector vaccine for COVID-19. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.27.21256193v1external icon.
- Lumley SF RG, Costantindes B., et al. An observational cohort study on the incidence of SARS-CoV-2 infection and B.1.1.7 variant infection in healthcare workers by antibody and vaccination status medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.09.21253218v1.full.pdfpdf iconexternal icon.
- Hall VJ, Foulkes S, Saei A, Andrews N, Oguti B, Charlett A, et al. COVID-19 vaccine coverage in health-care workers in England and effectiveness of BNT162b2 mRNA vaccine against infection (SIREN): a prospective, multicentre, cohort study. Lancet. 2021;397(10286):1725-35.
- Pritchard E. MP, Stoesser N., et al. Impact of vaccination on SARS-CoV-2 cases in the community: a population-based study using the UK’s COVID-19 Infection Survey. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.22.21255913v1.full.pdfpdf iconexternal icon.
- Shah A GC, Bishop J, et al. Effect of vaccination on transmission of COVID-19: an observational study in healthcare workers and their households. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.11.21253275v1external icon.
- Lopez Bernal J, Andrews N, Gower C, Robertson C, Stowe J, Tessier E, et al. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on covid-19 related symptoms, hospital admissions, and mortality in older adults in England: test negative case-control study. BMJ. 2021;373:n1088.
- Heymann AD. ZG, Shasha D., et. al. BNT162b2 Vaccine Effectiveness in Preventing Asymptomatic Infection with SARS-CoV-2 Virus: A Nationwide Historical Cohort Study. Lancet (preprint). 2021;https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3796868external icon.
- Aran D. Estimating real-world COVID-19 vaccine effectiveness in Israel using aggregated counts. Github. 2021;https://github.com/dviraran/covid_analyses/blob/master/Aran_letter.pdfpdf iconexternal icon.
- Dagan N, Barda N, Kepten E, Miron O, Perchik S, Katz MA, et al. BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting. N Engl J Med. 2021.
- Goldberg Y MM, Woodbridge Y, et al. Protection of previous SARS-CoV-2 infection is similar to that of BNT162b2 vaccine protection: A three-month nationwide experience from Israel. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.20.21255670v1external icon.
- Haas EJ, Angulo FJ, McLaughlin JM, Anis E, Singer SR, Khan F, et al. Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data. Lancet. 2021.
- Angel Y. SA, Henig O., et al. Association Between Vaccination With BNT162b2 and Incidence of Symptomatic and Asymptomatic SARS-CoV-2 Infections Among Health Care Workers. JAMA (preprint). 2021;https://pubmed.ncbi.nlm.nih.gov/33956048/external icon.
- Regev-Yochay G AS, Bergwerk M, et al. Decreased Infectivity Following BNT162b2 Vaccination. Lancet (preprint). 2021;https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3815668external icon.
- Fabiani M, Ramigni M, Gobbetto V, Mateo-Urdiales A, Pezzotti P, Piovesan C. Effectiveness of the Comirnaty (BNT162b2, BioNTech/Pfizer) vaccine in preventing SARS-CoV-2 infection among healthcare workers, Treviso province, Veneto region, Italy, 27 December 2020 to 24 March 2021. Euro Surveill. 2021;26(17).
- Moustsen-Helms I EH, Nielsen J, et. al. Vaccine effectiveness after 1st and 2nd dose of the BNT162b2 mRNA Covid-19 Vaccine in long-term care facility residents and healthcare workers – a Danish cohort study medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.08.21252200v1.full.pdf(Marchexternal icon 24, 2021).
- Björk J. IM, Moghaddassi M., et al. Effectiveness of the BNT162b2 vaccine in preventing COVID-19 in the working age population – first results from a cohort study in Southern Sweden. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.20.21254636v1external icon.
- Benenson S, Oster Y, Cohen MJ, Nir-Paz R. BNT162b2 mRNA Covid-19 Vaccine Effectiveness among Health Care Workers. N Engl J Med. 2021.
- Daniel W, Nivet M, Warner J, Podolsky DK. Early Evidence of the Effect of SARS-CoV-2 Vaccine at One Medical Center. N Engl J Med. 2021.
- Keehner J, Horton LE, Pfeffer MA, Longhurst CA, Schooley RT, Currier JS, et al. SARS-CoV-2 Infection after Vaccination in Health Care Workers in California. N Engl J Med. 2021.
- Boyarsky BJ, Werbel WA, Avery RK, Tobian AAR, Massie AB, Segev DL, et al. Immunogenicity of a Single Dose of SARS-CoV-2 Messenger RNA Vaccine in Solid Organ Transplant Recipients. JAMA. 2021.
- Boyarsky BJ, Ruddy JA, Connolly CM, Ou MT, Werbel WA, Garonzik-Wang JM, et al. Antibody response to a single dose of SARS-CoV-2 mRNA vaccine in patients with rheumatic and musculoskeletal diseases. Ann Rheum Dis. 2021.
- Chavarot N. OA, Olivier M, et.al. Poor Anti-SARS-CoV-2 Humoral and T-cell Responses After 2 Injections of mRNA Vaccine in Kidney Transplant Recipients Treated with Belatacept. Transplantation. 2021;https://journals.lww.com/transplantjournal/Citation/9000/Poor_Anti_SARS_CoV_2_Humoral_and_T_cell_Responses.95281.aspxexternal icon.
- Herishanu Y, Avivi I, Aharon A, Shefer G, Levi S, Bronstein Y, et al. Efficacy of the BNT162b2 mRNA COVID-19 Vaccine in Patients with Chronic Lymphocytic Leukemia. Blood. 2021.
- Rozen-Zvi B, Yahav D, Agur T, Zingerman B, Ben-Zvi H, Atamna A, et al. Antibody response to mRNA SARS-CoV-2 vaccine among kidney transplant recipients – Prospective cohort study. Clin Microbiol Infect. 2021.
- Simon B RH, Treipl A, et al. Hemodialysis Patients Show a Highly Diminished Antibody Response after COVID-19 mRNA Vaccination Compared to Healthy Controls. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.26.21254259v1external icon.
- Monin L, Laing AG, Munoz-Ruiz M, McKenzie DR, Del Molino Del Barrio I, Alaguthurai T, et al. Safety and immunogenicity of one versus two doses of the COVID-19 vaccine BNT162b2 for patients with cancer: interim analysis of a prospective observational study. Lancet Oncol. 2021.
- Yelin I KR, Herzel E, et al. Associations of the BNT162b2 COVID-19 vaccine effectiveness with patient age and comorbidities. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.16.21253686v1external icon.
- Tande AJ, Pollock BD, Shah ND, Farrugia G, Virk A, Swift M, et al. Impact of the COVID-19 Vaccine on Asymptomatic Infection Among Patients Undergoing Pre-Procedural COVID-19 Molecular Screening. Clin Infect Dis. 2021.
- Levine-Tiefenbrun M YI, Katz R, et al. . Decreased SARS-CoV-2 viral load following vaccination. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.02.06.21251283v1.full.pdfpdf iconexternal icon.
- Jones NK, Rivett L, Seaman S, Samworth RJ, Warne B, Workman C, et al. Single-dose BNT162b2 vaccine protects against asymptomatic SARS-CoV-2 infection. Elife. 2021;10.
- McEllistrem MC, Clancy CJ, Buehrle DJ, Lucas A, Decker BK. Single dose of a mRNA SARS-CoV-2 vaccine is associated with lower nasopharyngeal viral load among nursing home residents with asymptomatic COVID-19. Clin Infect Dis. 2021.
- Petter E MO, Zuckerman N, et al. Initial real world evidence for lower viral load of individuals who have been vaccinated by BNT162b2. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.02.08.21251329v1external icon.
- Levine-Tiefenbrun M, Yelin I, Katz R, Herzel E, Golan Z, Schreiber L, et al. Initial report of decreased SARS-CoV-2 viral load after inoculation with the BNT162b2 vaccine. Nat Med. 2021;27(5):790-2.
- Marks M, Millat-Martinez P, Ouchi D, Roberts CH, Alemany A, Corbacho-Monne M, et al. Transmission of COVID-19 in 282 clusters in Catalonia, Spain: a cohort study. Lancet Infect Dis. 2021.
- Harris RJ HJ, Zaidi A, et al. Impact of vaccination on household transmission of SARS-COV-2 in England. khubnet. 2021;https://khub.net/documents/135939561/390853656/Impact+of+vaccination+on+household+transmission+of+SARS-COV-2+in+England.pdf/35bf4bb1-6ade-d3eb-a39e-9c9b25a8122aexternal icon.
- Boyarsky BJ, Werbel WA, Avery RK, Tobian AAR, Massie AB, Segev DL, et al. Antibody Response to 2-Dose SARS-CoV-2 mRNA Vaccine Series in Solid Organ Transplant Recipients. JAMA. 2021.
- Grupper A, Rabinowich L, Schwartz D, Schwartz IF, Ben-Yehoyada M, Shashar M, et al. Reduced humoral response to mRNA SARS-CoV-2 BNT162b2 vaccine in kidney transplant recipients without prior exposure to the virus. Am J Transplant. 2021.
- Itzhaki Ben Zadok O, Shaul AA, Ben-Avraham B, Yaari V, Ben Zvi H, Shostak Y, et al. Immunogenicity of the BNT162b2 mRNA vaccine in heart transplant recipients – a prospective cohort study. Eur J Heart Fail. 2021.
- Rabinowich L GA, Baruch R, et al. Low immunogenicity to SARS-CoV-2 vaccination among liver transplant recipients. J Hepatol (online ahead of print). 2021;https://pubmed.ncbi.nlm.nih.gov/33892006/external icon.
- Centers for Disease Control and Prevention. SARS-CoV-2 Variant Classifications and Definitions [Available from: https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/variant-surveillance/variant-info.html
- Annavajhala MK, Mohri H, Zucker JE, Sheng Z, Wang P, Gomez-Simmonds A, et al. A Novel SARS-CoV-2 Variant of Concern, B.1.526, Identified in New York. medRxiv. 2021;https://www.ncbi.nlm.nih.gov/pubmed/33655278external icon.
- Becker M DA, Junker D, et al. Immune response to SARS-CoV-2 variants of concern in vaccinated individuals. medRxiv. 2021;https://doi.org/10.1101/2021.03.08.21252958external icon.
- Chen RE, Zhang X, Case JB, Winkler ES, Liu Y, VanBlargan LA, et al. Resistance of SARS-CoV-2 variants to neutralization by monoclonal and serum-derived polyclonal antibodies. Nat Med. 2021.
- Collier DA, De Marco A, Ferreira I, Meng B, Datir R, Walls AC, et al. Sensitivity of SARS-CoV-2 B.1.1.7 to mRNA vaccine-elicited antibodies. Nature. 2021.
- Edara VV, Hudson WH, Xie X, Ahmed R, Suthar MS. Neutralizing Antibodies Against SARS-CoV-2 Variants After Infection and Vaccination. JAMA. 2021.
- Garcia-Beltran WF, Lam EC, St Denis K, Nitido AD, Garcia ZH, Hauser BM, et al. Multiple SARS-CoV-2 variants escape neutralization by vaccine-induced humoral immunity. Cell. 2021.
- Kuzmina A KY, Voloshin O, et al. SARS CoV-2 Escape Variants Exhibit Differential Infectivity and Neutralization Sensitivity to Convalescent or Post-Vaccination Sera. Cell Host & Microbe. 2021.
- Liu Y, Liu J, Xia H, Zhang X, Fontes-Garfias CR, Swanson KA, et al. Neutralizing Activity of BNT162b2-Elicited Serum. N Engl J Med. 2021.
- Marot S MI, Jary A, et al. Neutralization heterogeneity of United Kingdom and South-African SARS-CoV-2 variants in BNT162b2-vaccinated or convalescent COVID-19 healthcare workers. bioRxiv. 2021;https://doi.org/10.1101/2021.03.05.434089external icon.
- Muik A, Wallisch AK, Sanger B, Swanson KA, Muhl J, Chen W, et al. Neutralization of SARS-CoV-2 lineage B.1.1.7 pseudovirus by BNT162b2 vaccine-elicited human sera. Science. 2021;371(6534):1152-3.
- Rathnasinghe R, Jangra S, Cupic A, Martinez-Romero C, Mulder LCF, Kehrer T, et al. The N501Y mutation in SARS-CoV-2 spike leads to morbidity in obese and aged mice and is neutralized by convalescent and post-vaccination human sera. medRxiv. 2021;https://www.ncbi.nlm.nih.gov/pubmed/33501468external icon.
- Sahin U MA, Vogler I, et al. BNT162b2 induces SARS-CoV-2-neutralising antibodies and T cells in humans. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2020.12.09.20245175v1external icon.
- Shen X, Tang H, McDanal C, Wagh K, Fischer W, Theiler J, et al. SARS-CoV-2 variant B.1.1.7 is susceptible to neutralizing antibodies elicited by ancestral spike vaccines. Cell Host Microbe. 2021.
- Skelly D HA, Gilbert-Jaramillo J, et al. Vaccine-induced immunity provides more robust heterotypic immunity than natural infection to emerging SARS-CoV-2 variants of concern. Research Square. 2021;https://www.researchsquare.com/article/rs-226857/v1external icon.
- Supasa P, Zhou D, Dejnirattisai W, Liu C, Mentzer AJ, Ginn HM, et al. Reduced neutralization of SARS-CoV-2 B.1.1.7 variant by convalescent and vaccine sera. Cell. 2021.
- Tada T, Dcosta BM, Samanovic-Golden M, Herati RS, Cornelius A, Mulligan MJ, et al. Neutralization of viruses with European, South African, and United States SARS-CoV-2 variant spike proteins by convalescent sera and BNT162b2 mRNA vaccine-elicited antibodies. bioRxiv. 2021;https://www.ncbi.nlm.nih.gov/pubmed/33564768external icon.
- Trinite B PE, Marfil S, et al. Previous SARS-CoV-2 infection increases B.1.1.7 cross-neutralization by vaccinated individuals. bioRxiv. 2021;https://doi.org/10.1101/2021.03.05.433800external icon.
- Wang P, Nair MS, Liu L, Iketani S, Luo Y, Guo Y, et al. Antibody Resistance of SARS-CoV-2 Variants B.1.351 and B.1.1.7. Nature. 2021.
- Wang Z, Schmidt F, Weisblum Y, Muecksch F, Barnes CO, Finkin S, et al. mRNA vaccine-elicited antibodies to SARS-CoV-2 and circulating variants. Nature. 2021.
- Wu K, Werner AP, Koch M, Choi A, Narayanan E, Stewart-Jones GBE, et al. Serum Neutralizing Activity Elicited by mRNA-1273 Vaccine. N Engl J Med. 2021.
- Xie X, Liu Y, Liu J, Zhang X, Zou J, Fontes-Garfias CR, et al. Neutralization of SARS-CoV-2 spike 69/70 deletion, E484K and N501Y variants by BNT162b2 vaccine-elicited sera. Nat Med. 2021.
- Zhou D, Dejnirattisai W, Supasa P, Liu C, Mentzer AJ, Ginn HM, et al. Evidence of escape of SARS-CoV-2 variant B.1.351 from natural and vaccine-induced sera. Cell. 2021.
- Zhou H DB, Samanovic M, et al. . B.1.526 SARS-CoV-2 variants identified in New York City are neutralized by vaccine-elicited and therapeutic monoclonal antibodies. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.03.24.436620v1.full.pdfpdf iconexternal icon.
- Madhi SA, Baillie V, Cutland CL, Voysey M, Koen AL, Fairlie L, et al. Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. N Engl J Med. 2021.
- Liu Y, Liu J, Xia H, Zhang X, Zou J, Fontes-Garfias CR, et al. BNT162b2-Elicited Neutralization against New SARS-CoV-2 Spike Variants. N Engl J Med. 2021.
- Ferreira I RD, Guido P, et al. SARS-CoV-2 B.1.617 emergence and sensitivity to vaccine-elicited antibodies. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.08.443253v2external icon.
- Tada T ZH, Dcosta BM, et al. The Spike Proteins of SARS-CoV-2 B.1.617 and B.1.618 Variants Identified in India Provide Partial Resistance to Vaccine-elicited and Therapeutic Monoclonal Antibodies. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.14.444076v1external icon.
- Bates T LH, Lyski ZL, et al. Neutralization of SARS-CoV-2 variants by convalescent and vaccinated serum. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.04.21254881v1external icon.
- Stankov MV CA, Bonifacius A, et al. Humoral and cellular immune responses against SARS-CoV-2 variants and human coronaviruses after single BNT162b2 vaccination. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.16.21255412v1external icon.
- McCallum M BJ, De Marco A, et al. SARS-CoV-2 immune evasion by variant B.1.427/B.1.429. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.03.31.437925v1external icon.
- Shen X, Tang H, Pajon R, Smith G, Glenn GM, Shi W, et al. Neutralization of SARS-CoV-2 Variants B.1.429 and B.1.351. N Engl J Med. 2021.
- West AP WJ, Wang JC, et al. Detection and characterization of the SARS-CoV-2 lineage B.1.526 in New York. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.02.14.431043v3external icon.
- Hoffmann M H-WH, Kruger N, et al. SARS-CoV-2 variant B.1.617 is resistant to Bamlanivimab and evades antibodies induced by infection and vaccination. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.04.442663v1external icon.
- Edara VV LL, Sahoo MK, et al. Infection and vaccine-induced neutralizing antibody responses to the SARS-CoV-2 B.1.617.1 variant. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.09.443299v1external icon.
- Gonzalez C. Saade C BA, et al. Live virus neutralisation testing in convalescent patients and subjects vaccinated against 19A, 20B, 20I/501Y.V1 and 20H/501Y.V2 isolates of SARS-CoV-2. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.05.11.21256578v1.full.pdfpdf iconexternal icon.
- Dejnirattisai W, Zhou D, Supasa P, Liu C, Mentzer AJ, Ginn HM, et al. Antibody evasion by the P.1 strain of SARS-CoV-2. Cell. 2021.
- Deng X, Garcia-Knight MA, Khalid MM, Servellita V, Wang C, Morris MK, et al. Transmission, infectivity, and neutralization of a spike L452R SARS-CoV-2 variant. Cell. 2021.
- Emary KRW, Golubchik T, Aley PK, Ariani CV, Angus B, Bibi S, et al. Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 variant of concern 202012/01 (B.1.1.7): an exploratory analysis of a randomised controlled trial. Lancet. 2021;397(10282):1351-62.
- Miyakawa K JS, Kato H, et al. Rapid detection of neutralizing antibodies to SARS-CoV-2 variants in post-vaccination sera. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.05.06.21256788v1external icon.
- Lilleri D VI, Bergami F, et al. SARS-CoV-2 mRNA vaccine BNT162b2 elicited a robust humoral and cellular response against SARS-CoV-2 variants. Research Square. 2021;https://www.researchsquare.com/article/rs-396284/v1external icon.
- Leier HC BT, Lyski ZL, et al. Previously infected vaccinees broadly neutralize SARS-CoV-2 variants. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.04.25.21256049v1external icon.
- Alenquer M FF, Lousa D, et al. Amino acids 484 and 494 of SARS-CoV-2 spike are hotspots of immune evasion affecting antibody but not ACE2 binding. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.04.22.441007v2external icon.
- Hoffmann M, Arora P, Gross R, Seidel A, Hornich BF, Hahn AS, et al. SARS-CoV-2 variants B.1.351 and P.1 escape from neutralizing antibodies. Cell. 2021;184(9):2384-93 e12.
- Planas D, Bruel T, Grzelak L, Guivel-Benhassine F, Staropoli I, Porrot F, et al. Sensitivity of infectious SARS-CoV-2 B.1.1.7 and B.1.351 variants to neutralizing antibodies. Nat Med. 2021;27(5):917-24.
- Stamatatos L, Czartoski J, Wan YH, Homad LJ, Rubin V, Glantz H, et al. mRNA vaccination boosts cross-variant neutralizing antibodies elicited by SARS-CoV-2 infection. Science. 2021.
- Jangra S, Ye C, Rathnasinghe R, Stadlbauer D, Personalized Virology Initiative study g, Krammer F, et al. SARS-CoV-2 spike E484K mutation reduces antibody neutralisation. Lancet Microbe. 2021.
- Pegu A OCS, Schmidt SD, et al. Durability of mRNA-1273-induced antibodies against SARS-CoV-2 variants. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.13.444010v1external icon.
- Wu K, Choi A, Koch M, et al. Preliminary Analysis of Safety and Immunogenicity of a SARS-CoV-2 Variant Vaccine Booster. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.05.05.21256716v1external icon.
- Gallagher KME, Leick MB, Larson RC, Berger TR, Katsis K, Yam JY, et al. SARS -CoV-2 T-cell immunity to variants of concern following vaccination. bioRxiv. 2021.
- Neidleman J LX, McGregor M, et al. mRNA vaccine-induced SARS-CoV-2-specific T cells recognize B.1.1.7 and B.1.351 variants but differ in longevity and homing properties depending on prior infection status. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.05.12.443888v1external icon.
- Tarke A SJ, Methot N, et al. Negligible impact of SARS-CoV-2 variants on CD4+ and CD8+ T cell reactivity in COVID-19 exposed donors and vaccinees. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.02.27.433180v1external icon.
- Woldemeskel BA, Garliss CC, Blankson JN. SARS-CoV-2 mRNA vaccines induce broad CD4+ T cell responses that recognize SARS-CoV-2 variants and HCoV-NL63. J Clin Invest. 2021;131(10).
- Motozono C TM, Zahradnik J, et al. An emerging SARS-CoV-2 mutant evading cellular immunity and increasing viral infectivity. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.04.02.438288v1external icon.
- Reynolds CJ, Pade C, Gibbons JM, Butler DK, Otter AD, Menacho K, et al. Prior SARS-CoV-2 infection rescues B and T cell responses to variants after first vaccine dose. Science. 2021.
- Pretti MAM GR, Farias AS, et al. New SARS-CoV-2 lineages could evade CD8+ T-cells response. bioRxiv. 2021;https://www.biorxiv.org/content/10.1101/2021.03.09.434584v2external icon.
- Abu-Raddad LJ, Chemaitelly H, Butt AA, National Study Group for C-V. Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants. N Engl J Med. 2021.
- Chu DK, Akl EA, Duda S, Solo K, Yaacoub S, Schunemann HJ, et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis. Lancet. 2020;395(10242):1973-87.
- Gallaway MS, Rigler J, Robinson S, Herrick K, Livar E, Komatsu KK, et al. Trends in COVID-19 Incidence After Implementation of Mitigation Measures – Arizona, January 22-August 7, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(40):1460-3.
- Haug N, Geyrhofer L, Londei A, Dervic E, Desvars-Larrive A, Loreto V, et al. Ranking the effectiveness of worldwide COVID-19 government interventions. Nat Hum Behav. 2020;4(12):1303-12.
- Honein MA, Christie A, Rose DA, Brooks JT, Meaney-Delman D, Cohn A, et al. Summary of Guidance for Public Health Strategies to Address High Levels of Community Transmission of SARS-CoV-2 and Related Deaths, December 2020. MMWR Morb Mortal Wkly Rep. 2020;69(49):1860-7.
- Kanu FA, Smith EE, Offutt-Powell T, Hong R, Delaware Case I, Contact Tracing T, et al. Declines in SARS-CoV-2 Transmission, Hospitalizations, and Mortality After Implementation of Mitigation Measures- Delaware, March-June 2020. MMWR Morb Mortal Wkly Rep. 2020;69(45):1691-4.
- Kucharski AJ, Klepac P, Conlan AJK, Kissler SM, Tang ML, Fry H, et al. Effectiveness of isolation, testing, contact tracing, and physical distancing on reducing transmission of SARS-CoV-2 in different settings: a mathematical modelling study. Lancet Infect Dis. 2020;20(10):1151-60.
- Alexander A RJ, Smetters K, et al. Epidemiological and Economic Effects of Lockdown. Brookings Papers on Economic Activity. 2020;https://www.brookings.edu/wp-content/uploads/2020/09/Arnon-et-al-conference-draft.pdfpdf iconexternal icon.
- Boserup B, McKenney M, Elkbuli A. Alarming trends in US domestic violence during the COVID-19 pandemic. Am J Emerg Med. 2020;38(12):2753-5.
- Brooks SK, Webster RK, Smith LE, Woodland L, Wessely S, Greenberg N, et al. The psychological impact of quarantine and how to reduce it: rapid review of the evidence. Lancet. 2020;395(10227):912-20.
- Czeisler ME, Lane RI, Petrosky E, Wiley JF, Christensen A, Njai R, et al. Mental Health, Substance Use, and Suicidal Ideation During the COVID-19 Pandemic – United States, June 24-30, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(32):1049-57.
- Holland KM, Jones C, Vivolo-Kantor AM, Idaikkadar N, Zwald M, Hoots B, et al. Trends in US Emergency Department Visits for Mental Health, Overdose, and Violence Outcomes Before and During the COVID-19 Pandemic. JAMA Psychiatry. 2021.
- McGinty EE, Presskreischer R, Han H, Barry CL. Psychological Distress and Loneliness Reported by US Adults in 2018 and April 2020. JAMA. 2020;324(1):93-4.
- Orben A, Tomova L, Blakemore SJ. The effects of social deprivation on adolescent development and mental health. Lancet Child Adolesc Health. 2020;4(8):634-40.
- UNESCO. Adverse consequences of school closures. https://en.unesco.org/covid19/educationresponse/consequencesexternal icon.
- Galanti M PS, Yamana TK, et al. The importance of continued non-pharmaceutical interventions during the upcoming SARS-COV-2 vaccination campaign. medRxiv. 2020;https://www.medrxiv.org/content/10.1101/2020.12.23.20248784v1external icon.
- Gozzi N BP, Perra N, et al. The importance of non-pharmaceutical interventions during the COVID-19 vaccine rollout. medRxiv. 2021; https://www.medrxiv.org/content/10.1101/2021.01.09.21249480v1.full.pdfpdf iconexternal icon.
- Gumel A IE, Ngonghala C, et al. Towards achieving a vaccine-derived herd immunity threshold for COVID-19 in the U.S. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2020.12.11.20247916v3external icon.
- Iboi EA, Ngonghala CN, Gumel AB. Will an imperfect vaccine curtail the COVID-19 pandemic in the U.S.? Infect Dis Model. 2020;5:510-24.
- Li J GP. Returning to a normal life via COVID-19 vaccines in the USA: a large-scale agent-based simulation study. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.01.31.21250872v1external icon.
- Love J KL, Angulo F, et al. Continued need for non-pharmaceutical interventions after COVID-19 vaccination in long-termcare facilities. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.01.06.21249339v1.full.pdfpdf iconexternal icon.
- Tang B LP, Yang J. The challenges of the coming mass vaccination and exit strategy in prevention and control of COVID-19, a modelling study. medRxiv. 2020;https://www.medrxiv.org/content/10.1101/2020.12.18.20248478v1external icon.
- Alvarez MM B-GS, Trujillo-de Santiago, G Modeling the effect of vaccination strategies in an Excel spreadsheet: The rate of vaccination, and not only the vaccination coverage, is a determinant for containing COVID-19 in urban areas. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.01.06.21249365v1.fullexternal icon.
- Borchering RK, Viboud C, Howerton E, Smith CP, Truelove S, Runge MC, et al. Modeling of Future COVID-19 Cases, Hospitalizations, and Deaths, by Vaccination Rates and Nonpharmaceutical Intervention Scenarios – United States, April-September 2021. MMWR Morb Mortal Wkly Rep. 2021;70(19):719-24.
- Kraay ANM GM, Ge Y, et al. Modeling the use of SARS-CoV-2 vaccination to safely relax non-pharmaceutical interventions. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.03.12.21253481v1.full.pdfpdf iconexternal icon.
- Shayak B SM, Mishra AK. COVID-19 Spreading Dynamics in an Age-Structured Population with Selective Relaxation of Restrictions for Vaccinated Individuals : a Mathematical Modeling Study. medRxiv. 2021;https://www.medrxiv.org/content/10.1101/2021.02.22.21252241v1.full.pdfpdf iconexternal icon.