In other words, I’m saying….

  1. WHO did indeed change the definition of herd immunity
  2. In the changed definition, natural immunity which has always been important in developing herd immunity, is eliminated
  3. CDC has also changed the definition of “vaccine” specifically so that mRNA gene therapy could be relabelled a “vaccine”
  4. Natural vs vaccine-induced immunity in measles can serve as one model for how that pertains to immunity in COVID-19

Claim 11: “The World Health Organization changed its definition of herd immunity in December 2020 to exclude natural infection, emphasising vaccines.”

“This goes against everything that we have known in immunology and about epidemiologic management of respiratory disease and infectious communicable diseases for a very long time,” claimed Dr Canaday.

NH: “Except it’s not true. The WHO on December 31 said herd immunity could come “either through vaccination or immunity developed through previous infection”. It backs the vaccination route of course because it avoids most unnecessary suffering and death.”

DrPC: NewsHub experts were not paying attention to what I said. I specifically pointed out that the original definition of herd immunity on the WHO website was from 9 June 2020 (R1), whereas the WHO definition in NewsHub’s response was indeed the changed definition that I had shown in my presentation as dated 31 December 2020. The definition provided by NewsHub is indeed the original definition from June that I had shown, not the changed definition that NewsHub claimed as being from December. What the WHO actually said in December was “WHO supports achieving ‘herd immunity’ through vaccination, not by allowing a disease to spread through any segment of the population, as this would result in unnecessary cases and deaths.” They also went on to state “Vaccinated people are protected from getting the disease in question and passing on the pathogen, breaking any chains of transmission.” (R2)

The obvious implication here is that WHO changed the definition to prepare the way to eliminate natural immunity as a means of contributing to herd immunity. This indeed does go against the conventional understanding of herd immunity which has pertained for many decades until 2020. Now only proprietary preparations by for-profit pharmaceutical manufacturers have been given the “green light” and imprimatur of the World Health Organisation.

Further, we see that the CDC has also changed the definition of “vaccine.”

In July 2012, CDC’s definition for vaccination wasInjection of a killed or weakened infectious organism in order to prevent the disease.” (R3) This is what we have known as a “traditional” vaccine.  In February 2015, CDC changed the definition of a vaccine to “a product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease,” (R4) and this definition still pertained until August 2021. (R5)

Then, all of a sudden, the definition of vaccine was changed to “a preparation that is used to stimulate the body’s immune response against diseases” in September 2021. So now we see that vaccines no longer must prevent disease, protect from disease, or produce immunity, but merely must “stimulate” an immune response [of some unspecified kind] against “diseases [not specifically stated].” (R6) And if you can’t prevent the disease, how are you going to prevent transmission of the virus?  

We enter now a world where mRNA “vaccines” are allowed and even emphasised, whereas conventional vaccine technology and natural immunity are given a “back seat.” We shall see in discussion of claim #6 that mRNA technology has historically originated in a search for a means of gene modification in hereditary diseases, in other words, gene therapy.

NH: “Dr Petousis-Harris said measles epidemics used to happen regularly until vaccines were introduced. Prior to vaccines everyone experienced the disease and became immune for the rest of their lives.”

DrPC: One can understand Dr Petousis-Harris’s enthusiasm for vaccinations in general, as she is co-leader of the Global Vaccine Data Network and was previously chair of the WHO Global Advisory Committee on Vaccine Safety which partners with Bill Gates’ GAVI. Additional affiliations of interest below. (§)

Yes, measles was not considered an “epidemic” when my generation, and several after mine, experienced measles as a routine childhood infectious disease. It was a significant childhood illness, but rarely leading to complications of pneumonia and meningoencephalitis, much less death in developed countries. Deaths from measles had already fallen by more than 98% prior to introduction of measles vaccination in the United States in 1963. (R7-pdf)

Much of the credit for the marked reduction in measles and many other infectious diseases related to steady improvements in public health and sanitation, improved water quality, and better access to food and health care. Severe measles has also been traced to vitamin A deficiency. (R8) Those who have experienced measles disease do become immune for the rest of their lives.

Vaccines, while they reduce the incidence of measles disease in childhood, do not lack a history of adverse effects. Recovery of measles vaccine-strain viruses has been noted in small bowel lesions, peripheral blood monocytes, and there has been a notable association of serious neurologic illness in children post measles vaccination. (R9)  Autoimmune disease following measles and other vaccinations has also been noted, such as multiple sclerosis, Guillain-Barrė syndrome, juvenile diabetes, juvenile rheumatoid arthritis, etc. (R10), although discussion of this matter is beyond the scope of responding to the NewsHub allegations generally.

NH: “Yet, despite this virtually perfect immunity, every few years there would be devastating epidemics.”

DrPC: Yes, indeed there are. “Even in highly vaccinated populations, substantial proportions of those infected in an outbreak will have been previously vaccinated,” according to a review in 2013 (R11), and even in those who have had the boosters that had been added to the vaccination schedule to offset the effects of waning immunity (R12).  Outbreaks such as in 2015 at Disneyland involving measles showed that 12% occurred in the vaccinated (R13).  Genotyping by PCR has confirmed that up to 38% of the 192 strains of measles viruses in the USA in 2015 were of vaccine-strain origin (R14), and some outbreaks have indeed been confirmed as due to vaccine strain origin (R15). So, measles vaccinations have not provided “virtually perfect immunity” contrary to what Dr Petousis-Harris asserts.


The WHO did indeed change its definition of herd immunity to accommodate a reliance on vaccination rather than the historical reliance on a combination of naturally acquired immunity and vaccination. The concept that this is necessary to avoid “unnecessary cases and deaths” presupposes that we really are dealing with an unprecedented and highly lethal global pandemic for which no significant underlying reservoir of immunity to similar viruses exists in the population. We will address these in discussion of claim #12 (regarding lethality of COVID-19) and claim #10 (regarding the degree of pre-existing immunity to coronaviruses in the population) respectively.

This concept also presupposes that vaccines prevent disease and prevent transmission (which the WHO stated), but the CDC no longer defines this as necessary in a vaccine. The reliance on vaccine-induced immunity also presupposes that there is no suitable therapeutic agent or combination of agents that is effective for the prevention of COVID-19 or for early- or late-stage treatment. We address this misconception in discussion of claim #24.

But is vaccine-induced immunity, which is now the entire emphasis of the WHO, and of the NZ government, superior to naturally acquired immunity? Dr Petousis-Harris has brought up the comparison of natural vs vaccine-induced immunity for measles in the current review of herd immunity, and we address this again in our discussion of claim #3. In any case, what difference does it make to New Zealanders since we haven’t seen enough COVID-19 to develop natural immunity anyway? Or have we? You may be surprised to find out.


R1: WHO original definition of herd immunity June 2020. https://web.archive.org/web/20201101161006/https:/www.who.int/news-room/q-a-detail/coronavirus-disease-covid-19-serology

R2: WHO changed definition of herd immunity December 2020. https://www.who.int/news-room/q-a-detail/coronavirus-disease-covid-19-serology

R3: CDC vaccine definition, July 2012. https://t.co/2eiRJbdMBn?amp=1

R4: CDC vaccine definition, Feb 2015. https://t.co/xfHLyKQL3I?amp=1

R5: CDC vaccine definition, Aug 2021. https://t.co/yjdLysHgQk?amp=1

R6: CDC vaccine definition, Sept 2021. https://t.co/dyoQ73SIRB?amp=1

R7: Measles mortality in the United States, 1900-1960. Figure 19, p. 85


R8: Studies 340 through 353 in Miller’s Review of Critical Vaccines Studies, Neil Z Miller, 2016.

R9: Alderslade et al. referenced in chapter 14, Dissolving Illusions: Disease, Vaccines and the Forgotten History. Suzanne Humpries, MD and Roman Bystrianyk, 2013.

R10: Autoimmune diseases and vaccinations. Eur J Dermatol. 2004 Mar-Apr;14(2):86-90. https://pubmed.ncbi.nlm.nih.gov/15196997/

R11: The genetic basis for interindividual immune response variation to measles vaccine: new understanding and new vaccine approaches. Expert review of vaccines12(1), 57–70. https://doi.org/10.1586/erv.12.134

R12: The role of secondary vaccine failures in measles outbreaks. American journal of public health79(4), 475–478. https://doi.org/10.2105/ajph.79.4.475

R13: HAN Archive – 00376|Health Alert Network (HAN) (cdc.gov)

R14: J Clin Microbiol 55:735–743 https://journals.asm.org/doi/pdf/10.1128/jcm.01879-16

R15: Vaccine strain measles from MMR vaccine?  https://thevaccinereaction.org/2019/04/vaccine-strain-measles-from-mmr-vaccine/

(§) Helen Petousis-Harris PhD (Auckland) is also on the Science Board of the Brighton Collaboration (BC) (now part of the Task Force for Global Health). Brighton Collaboration is funded by the Coalition for Epidemic Preparedness Innovations (CEPI) to produce the Safety Platform for Emergency vACcines (SPEAC). This group deals with expediting the production and distribution of vaccines during epidemics.

CEPI was founded in Davos, Switzerland, by the governments of Norway and India, the Bill & Melinda Gates Foundation, Wellcome Trust, and the World Economic Forum, and to date has secured financial support from Australia, Austria, Belgium, the Bill & Melinda Gates Foundation, Canada, Denmark, the European Commission, Ethiopia, Finland, Germany, Hungary, Iceland, Indonesia, Italy, Japan, Kuwait, Lithuania, Luxembourg, Malaysia, Mexico, Netherlands, New Zealand, Norway, Panama, Romania, Saudi Arabia, Serbia, Singapore, Switzerland, The Republic of Korea, United Kingdom, USAID, and Wellcome Trust.

Additionally, CEPI has also received support from private sector entities as well as public contributions through the UN Foundation COVID-19 Solidarity Response Fund.

At a March 2020 meeting, the matter of known immune enhancement causing lethal effects in vaccinated experimental subjects who were exposed to wild virus was discussed.

Lambert PH, Ambrosino DM, Andersen SR et al. Consensus summary report for CEPI/BC March 12–13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines – ScienceDirect.

https://brightoncollaboration.us/speac/  and   https://cepi.net/about/whoweare/