Pfizer's Covid-19 vaccine appears to work against mutation in new coronavirus strains, study finds

CNN's Dr. Sanjay Gupta looks at the increasing number of Covid-19 cases and deaths in the United States and explains why health experts are unsure when these numbers will peak.

Posted: Jan 9, 2021 6:51 PM


A new study provides early evidence that a Covid-19 vaccine might be effective against two new coronavirus strains first identified in South Africa and the UK, despite a concerning mutation.

The two strains share a mutation known as N501Y that scientists worry could allow the virus to evade the immune protection generated by a vaccine.

In research posted online Thursday, scientists found that antibodies from people who had received the Pfizer/BioNTech vaccine showed "no reduction in neutralization activity" against a version of the virus that carries the N501Y mutation, which they created in the lab.

In order to do this, researchers tested the virus against blood from 20 people who had received two doses of the vaccine as part of a clinical trial.

The N501Y mutation is located in the coronavirus' spike protein -- the same structure targeted by vaccines. The virus uses this protein to enter the cells it attacks.

This particular mutation appears to help the virus attach to human cells, which may partly explain why these new strains appear to be more transmissible. But it is just one of many mutations in both strains that scientists have worried could make the virus less susceptible to vaccines or treatments.

The study -- conducted by researchers at Pfizer and the University of Texas Medical Branch -- does not test the full array of these mutation, nor has it been peer-reviewed.

While viruses are expected to mutate -- often in ways that are neutral or even harmful to the virus -- experts say the whole is not merely the sum of the parts: Some mutations are known to interact with one another, occasionally changing the shape or function of structures like the spike protein.

"A limitation of this study is that the mutation was tested in isolation," Deborah Dunn-Walters, chair of the British Society for Immunology's taskforce on Covid-19 and immunology, said in a statement. She noted that mutations that may have a compound effect "should be tested together."

Because people usually make more than one type of antibody against a virus, experts say it's unlikely such a mutation would render the virus completely resistant to a vaccine. However, experts aren't so sure the new strains will have no impact at all.

"We will need to see actual protection from new variants in participants in the clinical trials that are still running to be sure the vaccine is equally effective," Alexander Edwards, associate professor in biomedical technology at University of Reading's school of pharmacy in the UK, said in a statement. Neither Edwards nor Dunn-Walters was involved in the new research.

If a virus is more transmissible or less susceptible to a vaccine, experts say that could also raise the bar for the number of people who would have to be vaccinated to achieve herd immunity.

In a statement last month, Pfizer said it had performed similar tests on "multiple mutant strains. To date, we have found consistent coverage of all the strains tested."

It will be important to continue "monitoring of the significance of changes for vaccine coverage," the researchers wrote in the new paper.

That's because of "the possibility that a future mutation ... might necessitate a vaccine strain change." Both Pfizer's and Moderna's vaccines use genetic technology that would allow the vaccines to be quickly adapted to account for mutations, they noted.

In a statement Friday, BioNTech said it and Pfizer "are encouraged by these early, in vitro study findings," but stressed that "further data are needed" to track the how effective the vaccine is at preventing disease caused by new variants.

Mississippi Coronavirus Cases

Data is updated nightly.

Cases: 268672

Reported Deaths: 5917
CountyCasesDeaths
DeSoto17928195
Hinds17030337
Harrison14510212
Rankin11315223
Jackson11054193
Lee9109147
Madison8663171
Jones6853120
Forrest6260125
Lauderdale6161196
Lowndes5582123
Lafayette5269101
Lamar508765
Washington4965125
Bolivar4164110
Oktibbeha411585
Panola389881
Pontotoc380460
Monroe3727111
Warren3716103
Marshall360172
Union360165
Pearl River3527106
Neshoba3516158
Leflore3132110
Lincoln308389
Hancock300963
Sunflower294277
Tate281862
Alcorn274055
Pike272984
Itawamba271263
Scott264055
Yazoo258456
Prentiss255454
Coahoma252455
Copiah251549
Tippah251551
Simpson244872
Leake238967
Marion228274
Covington224873
Grenada224673
Wayne216336
Adams216271
Winston208271
George206440
Newton201447
Attala197465
Tishomingo196361
Chickasaw190245
Jasper183138
Holmes172568
Clay168637
Tallahatchie158035
Stone153625
Clarke148762
Calhoun142022
Smith131926
Yalobusha124935
Walthall115438
Greene114929
Noxubee114526
Montgomery112936
Lawrence107917
Carroll106922
Perry105931
Amite102727
Webster98024
Claiborne90125
Tunica89621
Jefferson Davis89330
Benton86923
Humphreys85625
Kemper81220
Quitman7169
Franklin71017
Choctaw64013
Wilkinson60125
Jefferson57321
Sharkey45717
Issaquena1616
Unassigned00

Alabama Coronavirus Cases

Cases: 445909

Reported Deaths: 6896
CountyCasesDeaths
Jefferson651891049
Mobile32138590
Madison28596223
Tuscaloosa21703276
Montgomery20220336
Shelby19584138
Baldwin17496216
Lee13378109
Morgan12741145
Etowah12196189
Calhoun11626228
Marshall10513126
Houston9097168
Limestone842481
Cullman8363125
Elmore8283112
Lauderdale7986112
DeKalb7935112
St. Clair7915139
Talladega6552112
Walker6068184
Jackson605649
Colbert560194
Blount551794
Autauga544065
Coffee470569
Dale415186
Franklin378150
Russell362816
Chilton348079
Covington344681
Escambia342244
Tallapoosa3184109
Dallas314197
Chambers308575
Clarke307339
Pike267735
Lawrence256958
Marion255763
Winston235243
Bibb224751
Geneva214747
Marengo212031
Pickens201831
Barbour188240
Hale187444
Fayette181230
Butler175960
Cherokee167433
Henry161325
Monroe153521
Randolph148236
Washington144027
Clay131050
Crenshaw126245
Macon124337
Cleburne123627
Lamar121324
Lowndes117636
Wilcox109422
Bullock105829
Perry100518
Conecuh98222
Sumter90828
Greene78323
Coosa64619
Choctaw52224
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