IBOV 171,317.18 ▼ 2.50% IPC MEX 69,711.87 ▲ 0.35% MERVAL 2,848,945 — — USD/BRL5.38▲ 0.65% USD/MXN18.69▲ 0.06% USD/CLP989.12▲ 0.47% USD/COP3,167▲ 0.58% USD/PEN3.45▲ 0.17% USD/ARS1,542▲ 0.21% USD/UYU40.21▲ 3.49% USD/PYG5,818▲ 4.31% USD/BOB11.92▲ 3.69% USD/DOP60.13▲ 0.05% USD/CRC451.45▲ 2.36% USD/GTQ7.64▲ 3.21% USD/HNL26.87▲ 0.25% USD/NIO36.62▼ 0.02% USD/VES885.90▼ 0.13% USD/PAB1.00— 0.00% USD/BZD2.00— 0.00% USD/JMD157.85▲ 2.62% USD/TTD6.75▲ 2.53% EUR/BRL5.99▼ 0.15% BRENT 109.58 ▼ 5.38% WTI 100.12 ▼ 1.61% IRON ORE 161.91 — — COPPER 6.65 ▲ 2.24% GOLD 4,073 ▲ 0.85% SILVER 54.49 ▲ 0.70% SOY 1,250 ▲ 0.70% CORN 450.25 ▼ 1.04% WHEAT 614.75 ▼ 0.20% COFFEE 294.35 ▼ 2.19% SUGAR 19.26 ▲ 0.84% ORANGE JUICE 143.20 ▲ 5.45% COTTON 77.90 ▼ 1.47% COCOA 5,581 ▲ 1.66% BEEF 230.73 ▲ 0.33% CATTLE 346.40 ▼ 1.00% LITHIUM 62.43 ▲ 1.89% PETR4 53.31 ▼ 1.06% VALE3 62.88 ▼ 2.33% ITUB4 41.42 ▼ 0.67% BBDC4 15.69 ▼ 1.63% ABEV3 15.40 ▲ 0.20% BBAS3 17.59 ▲ 0.69% B3SA3 15.27 ▲ 1.33% WEGE3 45.78 ▲ 2.81% PRIO3 69.21 ▼ 2.71% SUZB3 47.14 ▼ 0.55% RENT3 31.14 ▼ 1.67% AZZA3 16.72 ▲ 1.15% CSAN3 2.69 ▼ 2.89% RAIZ4 0.34 — 0.00% PCAR3 2.22 ▼ 3.48% GMAT3 3.74 ▲ 2.19% PSSA3 47.75 ▼ 0.89% CVCB3 0.98 — 0.00% POSI3 3.56 ▼ 0.84% SLCE3 16.97 ▼ 2.75% NATU3 5.68 ▼ 3.89% BRKM5 3.80 ▲ 19.50% RANI3 7.34 ▼ 0.54% CSNA3 4.76 ▼ 4.99% IBOV 171,317.18 ▼ 2.50% IPC MEX 69,711.87 ▲ 0.35% MERVAL 2,848,945 — — USD/BRL 5.34 ▼ 1.32% USD/MXN 18.69 ▲ 0.62% USD/CLP 983.47 ▼ 0.57% USD/COP 3,149 ▲ 3.06% USD/PEN 3.45 ▲ 0.17% USD/ARS 1,537 ▼ 0.28% USD/UYU 40.21 ▲ 3.57% USD/PYG 5,803 ▲ 3.78% USD/BOB 11.97 ▲ 4.93% USD/DOP 60.54 ▲ 1.83% USD/CRC 451.24 ▲ 2.13% USD/GTQ 7.64 ▲ 3.23% USD/HNL 26.87 ▲ 3.37% USD/NIO 36.62 ▲ 2.81% USD/VES 885.08 ▼ 0.13% USD/PAB 1.00 — 0.00% USD/BZD 2.00 — 0.00% USD/JMD 157.69 ▲ 2.63% USD/TTD 6.71 ▲ 2.07% EUR/BRL 5.95 ▲ 7.53% BRENT 109.58 ▼ 5.38% WTI 100.12 ▼ 1.61% IRON ORE 161.91 — — COPPER 6.65 ▲ 2.24% GOLD 4,073 ▲ 0.85% SILVER 54.49 ▲ 0.70% SOY 1,250 ▲ 0.70% CORN 450.25 ▼ 1.04% WHEAT 614.75 ▼ 0.20% COFFEE 294.35 ▼ 2.19% SUGAR 19.26 ▲ 0.84% ORANGE JUICE 143.20 ▲ 5.45% COTTON 77.90 ▼ 1.47% COCOA 5,581 ▲ 1.66% BEEF 230.73 ▲ 0.33% CATTLE 346.40 ▼ 1.00% LITHIUM 62.43 ▲ 1.89% PETR4 53.31 ▼ 1.06% VALE3 62.88 ▼ 2.33% ITUB4 41.42 ▼ 0.67% BBDC4 15.69 ▼ 1.63% ABEV3 15.40 ▲ 0.20% BBAS3 17.59 ▲ 0.69% B3SA3 15.27 ▲ 1.33% WEGE3 45.78 ▲ 2.81% PRIO3 69.21 ▼ 2.71% SUZB3 47.14 ▼ 0.55% RENT3 31.14 ▼ 1.67% AZZA3 16.72 ▲ 1.15% CSAN3 2.69 ▼ 2.89% RAIZ4 0.34 — 0.00% PCAR3 2.22 ▼ 3.48% GMAT3 3.74 ▲ 2.19% PSSA3 47.75 ▼ 0.89% CVCB3 0.98 — 0.00% POSI3 3.56 ▼ 0.84% SLCE3 16.97 ▼ 2.75% NATU3 5.68 ▼ 3.89% BRKM5 3.80 ▲ 19.50% RANI3 7.34 ▼ 0.54% CSNA3 4.76 ▼ 4.99%
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Wednesday, October 28, 2026

Scientific study from Israel shows natural immunity superior to Covid vaccine against Delta variant

By · August 28, 2021 · 3 min read

RIO DE JANEIRO, BRAZIL – The global debate of Covid mRNA vaccine mandates and passports has ignited social media, policymakers, and policies that impact just nearly every aspect of public life.

According to a new Israeli study, the natural immune protection that develops after a SARS-CoV-2 infection offers considerably more of a shield against the Delta variant of the pandemic coronavirus than two doses of the Pfizer-BioNTech vaccine.

It’s the largest real-world observational study so far to compare natural and vaccine-induced immunity to SARS-CoV-2, according to its leaders.

For many infectious diseases, naturally acquired immunity is more powerful than vaccine-induced immunity, and it often lasts a lifetime.
For many infectious diseases, naturally acquired immunity is more powerful than vaccine-induced immunity, and it often lasts a lifetime.
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Researchers at Maccabi Healthcare and Tel Aviv University compared the outcomes of over 76,000 Israelis in three groups.

The groups in the study were:
1. the doubly vaccinated (with the Pfizer vaccine)
2. Previously Covid infected but unvaccinated
3. Previously Covid infected with only a single vaccine dose

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The newly released data show people who once had a SARS-CoV-2 infection were much less likely than vaccinated people to get Delta, develop symptoms from it, or become hospitalized with serious Covid-19.COMIRNATY is the brand name for the Pfizer-BioNTech COVID-19 Vaccine. Now that the FDA-authorized Pfizer-BioNTech COVID-19 vaccine has been approved by the FDA.

The Israeli researchers discovered that immunity acquired through infection from Covid-19 is superior to immunity from the Pfizer-BioNTech vaccine. The study also found that fully vaccinated but uninfected people were significantly more likely to have a “breakthrough” Covid infection than people who had previously been infected and recovered from the disease.

“This study demonstrated that natural immunity confers longer-lasting and stronger protection against infection, symptomatic disease and hospitalization caused by the Delta variant,” the authors conclude.

The study, conducted in one of the most highly Covid-19–vaccinated countries in the world, examined the medical records of tens of thousands of Israelis, charting their infections, symptoms, and hospitalizations between 1 June and 14 August, when the Delta variant predominated in Israel.

No one in the study who got a new SARS-CoV-2 infection died—which prevented comparison of death rates but is a clear sign that vaccines still offer a formidable shield against serious disease, even if not as good as natural immunity.

For many infectious diseases, naturally acquired immunity is more powerful than vaccine-induced immunity, and it often lasts a lifetime. Other coronaviruses that cause the serious human disease SARS and the MERS trigger robust and persistent immune responses.

At the same time, several other human coronaviruses, which usually cause little more than colds, are known to reinfect people regularly.

Keep in mind, the Israeli study is only published as a preprint at this stage and has not been peer-reviewed. There was no external funding for the project.

HERD IMMUNITY MUST BE ACHIEVED BY VIRUS TRANSMISSION SAYS ICELAND AFTER FULL VACCINATION

Thorolfur Guðnason, Iceland’s epidemiologist, believes that the country must now try to achieve herd immunity to the coronavirus by letting it continue, but try to prevent severe disease by protecting vulnerable groups.

He said the goal at this point could not be to eradicate the virus from the community.

A record number of infected people have been diagnosed in recent weeks, even though most of the population has been vaccinated.

“There’s really nothing else we can do,” Guðnason confirmed when asked if 70- to 80-year-olds need to catch the disease to achieve herd immunity.

Iceland is one of the most vaccinated countries in the world, with 71.3% fully immunized people. The country has also managed to simultaneously boost its economy and have one of the lowest death rates in the world.

This has been done safely with the help of the country’s effective track and trace system, rigorous testing, and social distancing.

This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief

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