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Elimination could be the optimal response strategy for covid-19 and other emerging pandemic diseases

BMJ 2020; 371 doi: (Published 22 December 2020) Cite this as: BMJ 2020;371:m4907

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Are We Killing The COVID Canary?

Dear Editor

Are We Killing The COVID Canary?

Cough is one of the most important warning symptoms of COVID-19. It's like a canary in a coal mine... A warning of possible infection. It warns workers to stay at home… to self isolate. It warns the cougher to get tested… It warns contacts to ’stay away,' be careful, to self isolate and get tested, 'just in case.' In a sense cough and other common symptoms are a Covid-19 canary.

Clinical trials have shown that Covid-19 vaccines suppress symptoms including cough. If the vaccines stop symptoms, but don't stop transmission then we’ve lost our warning. No staying at home 'just in case.' No testing to find out our COVID-19 status. No self isolation to protect others. No followup contact tracing. Vaccinated but infected people just going about their daily activities infecting others. Infecting the vulnerable we think we are protecting by being vaccinated. Infecting our colleagues at work. Infecting our family and friends in the community. All of the above.

In New Zealand, border staff are being prioritised for vaccination on the assumption that vaccination stops transmission thereby protecting the community from border breaches. If the vaccines are suppressing symptoms but not stopping transmission then are we actually increasing the risk of community transmission rather than reducing it?

What does the FDA say in its Q&A’s regarding fast tracking these vaccines?

Q: If a person has received the the Pfizer-BioNTech COVID-19 Vaccine, will the vaccine protect against transmission of SARS-CoV-2 from individuals who are infected despite vaccination?

A: Most vaccines that protect from viral illnesses also reduce transmission of the virus that causes the disease by those who are vaccinated. While it is hoped this will be the case, the scientific community does not yet know if the Pfizer-BioNTech COVID-19 Vaccine will reduce such transmission. (1)

In other words, these vaccines have been allowed to be marketed (not approved) in the HOPE that they will reduce transmission.

In a subsequent press release the FDA have said, "At this time, data are not available to determine how long the vaccine will provide protection, nor is there evidence that the vaccine prevents transmission of SARS-CoV-2 from person to person.” (2)

The UK’s deputy chief medical officer, Professor Jonathan Van-Tam, went a step further and used the word ‘magic’ and ‘hope’ in the same breath in explaining that people must continue to be extremely cautious about transmission even after they’ve been vaccinated. (3)

The scientific community actually knows quite a lot about the relative ineffectiveness of intra muscular vaccines in preventing transmission of respiratory infections. We know that IM vaccines stimulate an IgG immune response, but they don’t stimulate a mucosal IgA immune response. We know that mucosal IgA immune response is a major component of prevention of infection and transmission of respiratory infections.(4)

Without prevention of transmission there can be no vaccine herd immunity, the very thing we have been promised to break the back of the pandemic.

The first person to be given an FDA authorised COVID-19 vaccine generated the headline, "I Trust Science.” (5)

Another early recipient of a vaccine, a nurse, was interviewed on TV and said, “I have had the vaccine because now that I’m protected, it will be safe for me to go and visit my elderly parents whom I haven’t been able to visit for nearly a year.”

Given that it is a year since these vaccines were conceived it beggars belief that our regulators haven’t mandated the simple addition of tests for carriage and transmission of SARS-CoV-2 virus post vaccination. It is as if they don’t want science to get in their way of their hope and magic.

When scientists talk in terms of “hope" and “magic,” on what basis do we trust science?

Are we killing the COVID-19 canary?

Ron Law
Risk & Policy Adviser

(1) Pfizer-BioNTech COVID-19 Vaccine Frequently Asked Questions

(2) FDA Takes Additional Action in Fight Against COVID-19 By Issuing Emergency Use Authorization for Second COVID-19 Vaccine
Action Follows Thorough Evaluation of Available Safety, Effectiveness, and Manufacturing Quality Information by FDA Career Scientists, Input from Independent Experts

(3) How effective will the coronavirus vaccine be at reducing the spread of Covid-19?

(4) Krammer, F. SARS-CoV-2 vaccines in development. Nature 586, 516–527 (2020).,


Competing interests: No competing interests

18 January 2021
Ron Law
Risk & Policy Adviser
Auckland, New Zealand