Infection generates natural immunity

Which seems good and long lasting and cheap, lots of evidence below.

Biological studies

Dan et al (2021) Science, Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection.

95% of participants tested retained immune memory at about 6 months after having COVID-19

More than 90% of participants had CD4+ T-cell memory at 1 month,

and 6–8 months after having COVID-19

Wang et al (2021) Science, Ultrapotent antibodies against diverse and highly transmissible SARS-CoV-2 variants

Previous SARS-CoV-2 infection,

with an ancestral variant produce antibodies that cross-neutralise emerging variants of concern with high potency

Epidemiological studies

Hansen et al (2021) Lancet, Assessment of protection against reinfection with SARS-CoV-2 among 4 million PCR-tested individuals in Denmark in 2020: a population-level observational study

People who had had COVID-19 previously were around 80·5% protected against reinfection

Pilz et al (2021) European Journal of Clinical Investigation, SARS-CoV-2 re-infection risk in Austria

Sheehan et al (2021) Clinical Infectious Diseases, Reinfection rates among patients who previously tested positive for COVID-19: a retrospective cohort study

Shrestha et al (2021) Preprint, Necessity of COVID-19 vaccination in previously infected individuals

Retrospective cohort study in the USA,

People who had had COVID-19 previously were 100% protected against reinfection

Gazit et al (2021) Preprint, Comparing SARS-CoV-2 natural immunity to vaccine-induced immunity: reinfections versus breakthrough infections

Kojima et al (2021) Preprint, Incidence of severe acute respiratory syndrome coronavirus-2 infection among previously infected or vaccinated employees

Laboratory staff routinely screened for SARS-CoV-2,

people who had had COVID-19 previously were 100% protected against reinfection

Clinical studies

Large, multicentre, prospective cohort study

Previous COVID-19 diagnosis,

84% decreased risk of infection

Letizia et al (2021) Lancet, Respiratory Medicine, SARS-CoV-2 seropositivity and subsequent infection risk in healthy young adults: a prospective cohort study

Prospective cohort of US Marines,

seropositive young adults were 82% protected against reinfection

Adnan et al (2021) Clinical Infectious Diseases, Reinfection With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Patients Undergoing Serial Laboratory Testing

N = 9,119, serial tests

Reinfection rates, 0.7%

So

Risk of repeat SARS-CoV-2 infection decreased by 80·5–100% among those who had had COVID-19

Protection from reinfection is strong and persists for more than 10 months of follow-up, (Hansen et al 2021 Lancet)

Turner, et al Nature, SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans

Madhuumita et al, Plos One, T cell response to SARS-CoV-2 infection in humans: A systematic review

SARS-CoV-2 infection induces specific and durable T-cell immunity,

Nina et al, (2020) Nature, SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls

Memory B-cell response to SARS-CoV-2 evolves between 1·3 and 6·2 months after infection, which is consistent with longer-term protection

Some people who have recovered from COVID-19 might not benefit from COVID-19 vaccination

One study found that previous COVID-19 was associated with increased adverse events following vaccination with Pfizer

In Switzerland, proof of recovered infection, in the past 12 months are considered equally protected as fully vaccinated,

[Mrashy]

you deserve a Knighthood for your time effort and first class presenting on the pandemic giving the actual facts all the way through and answering questions that need answering...thank you Dr John:)

[zeros]

I live as part of a large extended family of 18 in a densely populated poorer suburb of Bangkok. Omicron has invaded our community with many double and triple vaxxed people succumbing to the virus. It's strange but I do not know one person in our community with natural immunity who has tested positive to omicron. Out of the ten of us that were hospitalised with delta so far not one of us has tested positive or are showing any symptoms. This surprises us because we have been and still are surrounded by positive cases. So just maybe natural immunity from delta does provide some degree of protection from omicron. Just an uneducated observation.

[angieaiellomontes]

What a pleasure to listen to him every day and appreciate his complilation and analysis work so much. Some time ago, in a situation of analysis (the debate was between the placement or not of bone fillers in the maxillary sinuses) the studies showed that there were no better results than letting a simple and majestic blood clot perform said repair. But, they still wanted to use those fillers. Reason why I approached one of my dearest theachers and when I asked about not understanding, said doctor answered me: "dear doctor, when you do not understand something so clear and logical... there is a lot of money in the fund". With all my love, I pass on this wise comment to you, dear Dr. Campbell. Thank you very much for being the professional that he is.

[blammela]

This is great and frustrating at the same time. I have been asking about antigen testing since March 2020. I’m glad that we are hopefully coming around and turning a corner!

[HappyBagger]

Outstanding presentation. Real data, real science. No wonder you didn't get chance to do a video yesterday. This is some work. Thank you sir.

[navg]

Dear Dr Campbell, I started watching ur videos in Feb 2020! And being a person with zero medical knowledge, ur videos have been the only source of knowledge in language for commoners like me. I'm honoured to have been ur subscriber for past 2 years..thank u sir..love from uniformed man from India 🙏

[TheMrlandman]

Dr. Campbell, you have been a voice of reason and a beacon of hope in the pool of uninformed MSM. We, your viewers owe you a lot of gratitude. You're a gem, you deserve knighthood.

[sarahstrong]

Dear John, you have been a beacon of sanity in these crazy times.

[boulderangel]

I'm hooked on your honest reporting of the facts, Dr. Campbell. I look forward to your daily updates on this evolving situation. You, sir, are a real scientist and doctor.

[johnmoss]

Thank You Dr.Campbell for your rigorous study and presentation of Covid data. I feel that you are a rock in the sea of covid misinformation and I am profoundly thankful to hear actual "science" (with supporting data) as opposed to those who state "Science" without any supporting data.
"Science" without supporting data is merely uninformed opinion.

[GodofWarChuka]

I went through Omicron back in January with good natural immunity now. But I have some people, like my dad, doctor still telling me to get the Booster. But, it seems like most people are saying avoid the Vaccines and boosters.

[AmazingPhilippines]

Excellent review of these studies Dr. Campbell. 10's of millions of Filipinos in this densely populated nation have certainly recovered and yet the government and "experts" refuse to consider this science and still pushing for all to be vaxed despite many possible bad side effects as stated.

[earlgreystoke]

Thank you for your calm, factual explanations. Much appreciated!

[rachaeldover]

So grateful for all the videos you've been making, John. I've been following you since the beginning. You're a beacon of light during this very dark time. Thank you for keeping us informed and taking the risks you do to do this. Thank you thank you thank Much love and appreciation from Ohio, U.S. ☼

[EpicFailfun]

Hi John, just wanted to say that from my experience, infection definately gives strong long term immunity. I was unlucky to have confirmed covid in May 2020. Since then I've had multiple contacts with several covid cases (family i live with and ppl at work) confirmed with tests and actively spreading the virus with cough and sneezing. Even though I was exposed many times I've never caught covid again. I was testing myself every time i was in contact with such person but but was always negative and had no symptomes, so these studies strongly support my experience with covid and immunity.

[nd]

Thank you Dr. Campbell. I’m so glad I found your channel at the beginning of the Pandemic. Keeping it real, following the science. And most importantly taking the time, energy to make it simple enough for us to understand. 🙏🏼🙏🏼🙏🏼

[kath]

"Natural immunity is really pretty good." And it always has been even though certain "experts" decried that it no longer worked that way. Nice to see we're finally returning to what "the science" has always said and supported. It's really criminal that our health organizations are so far behind and not even trying to catch up.

[fatmanjoh]

The great worry I have with our government’s ( New Zealand) response to Omicron by limiting spread amongst the general population is that we will be stuck with a prolonged epidemic and an increased risk of further mutations. And we cannot rule out that one of these inevitable mutations could be more pathogenic with disastrous mortality in its wake. Out politicians had proven time and time again that they are not just behind the ball but not even in the game.

[judyvoltz]

We appreciate your wisdom and logic during this time of so much noise!

[bearsmom]

I retired as a nurse 1 year before covid started. (Thank God) After seeing all of this evidence on natural immunity, it makes me so angry that the US government will not give up on the vaccine mandates and experienced health care workers, first responders and even military members are losing their careers because of it! 😡