Neutralizing antibodies after vaccination and Covid infection: Effect on Mutants

Journal of American Medical Association (JAMA)

Salient Features

• Serum neutralizing antibodies rapidly appear after SARS-CoV-2 infection and vaccination

• This study compared neutralizing antibody response of previously infected and vaccinated person against mutants.

• Serum from PCR confirmed cases and also from vaccinated persons were tested with variants (Mutants) for neutralizing potential. These were:
1. Original Wuhan Virus
2. The second variant from patient in Atlanta, Georgia, (( EHC-083E (B.1 lineage), containing a D614G mutation )
3.Third variant, was UK strain and has concerns of increased
transmissibility (B.1.1.7 (SARS-CoV-2/human/USA/ CA_CDC_5574/2020),
4. The fourth variant,( N501Y SARS-CoV-2 virus,) containing a mutation in the
critical receptor binding domain of the spike

• Live-virus focus reduction neutralization tests(FRNTs)were Performed

• This study found neutralizing activity of infection-and vaccine- elicited antibodies against 4SARS-CoV-2 variants (Mutants)

Because neutralization studies measure the ability of antibodies to block virus

infection, these results suggest that infection- and vaccine induced immunity may be retained against the variants

My Take on the Subject

There is a great concern of re-infection with mutant strains with

altered transmission potential and severity. It is also not well

understood weather vaccination would provide immunity against

mutant strains. It is known from the studies that immunity after

infection lasts for at least 7 months. This well conducted laboratory

study proves that both natural infection and vaccination is likely to

provide protection against mutants. This is quite re-assuring. The

word of caution is that this is a small study and not all the mutants

were tested. This is going to be a long fight against this wretched

disease and vaccinations may need to be altered periodically to fight

mutants (as with influenza vaccine)

This brings up the issue of vaccinating individuals who have had

infection in the past. There is big YES as this would certainly enhance


India is witnessing second surge of cases. We can not afford the

whole population to be infected with the disease which has significant

mortality besides suffering and burden on health care compromising

care for other diseases which is severely affected in last one year.

Therefore, there is dire need for enhancing the vaccination drive and

every citizen has a responsibility for coming forward for vaccination as

`your protection is also protection of rest of the family members and

community at large.

It is proven that vaccination reduces the rate of infection. However,

more importantly it almost eliminates chances of severe life

threatening infection and death. This brings another issue that

vaccinated individuals with asymptomatic (or with mild symptom)

would have more chances of transmitting infection as they would be

active and moving around (and not test for Covid) without knowing of

their transmission potential. Therefore, it is v v important to follow

`COVID APPROPRIATE BEHAVIOUR’ after effective vaccination to

contain this disease

• •


G C Khilnani

Chairman, PSRI Institute of Pulmonary, Critical care and Sleep Medicine, PSRI Hospital, New Delhi.
Formerly, Professor and Head Dept of Pulmonary Critical care and Sleep Medicine, AIIMS, New Delhi-110029


NB: Please circulate to disseminate information

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