IBOV 172,236.05 ▲ 2.22% IPC MEX 72,104.80 ▲ 1.00% MERVAL 2,848,945 — — USD/BRL5.51▲ 0.04% USD/MXN18.51▼ 0.63% USD/CLP966.96▼ 0.99% USD/COP3,269▲ 0.88% USD/PEN3.41▼ 1.07% USD/ARS1,545▼ 0.02% USD/UYU40.45▲ 0.35% USD/PYG6,450▲ 1.45% USD/BOB11.74▼ 0.59% USD/DOP60.46▼ 0.21% USD/CRC446.56▼ 0.38% USD/GTQ7.64▼ 0.05% USD/HNL26.89▲ 0.02% USD/NIO 36.62 — 0.00% USD/VES897.02▲ 0.07% USD/PAB1.00— 0.00% USD/BZD2.00— 0.00% USD/JMD157.79▼ 0.02% USD/TTD6.72▼ 0.03% EUR/BRL6.18▲ 0.85% BRENT 91.69 ▼ 0.95% WTI 85.87 ▼ 1.13% IRON ORE 161.91 — — COPPER 6.35 ▲ 0.31% GOLD 4,123 ▲ 0.21% SILVER 53.12 ▲ 1.06% SOY 1,190 ▲ 0.61% CORN 440.75 ▲ 0.34% WHEAT 588.75 ▲ 0.13% COFFEE 266.70 ▼ 4.75% SUGAR 18.21 ▼ 0.16% ORANGE JUICE 143.50 ▲ 7.85% COTTON 78.65 ▼ 0.58% COCOA 5,113 ▼ 0.81% BEEF 216.33 ▲ 1.06% CATTLE 324.80 ▲ 0.77% LITHIUM 61.35 ▲ 0.72% PETR4 45.19 ▼ 0.24% VALE3 66.11 ▲ 3.23% ITUB4 41.72 ▲ 2.94% BBDC4 14.68 ▲ 3.38% ABEV3 15.61 ▲ 0.84% BBAS3 17.02 ▼ 0.64% B3SA3 14.85 ▲ 3.20% WEGE3 50.74 ▲ 5.29% PRIO3 59.39 ▼ 1.80% SUZB3 54.20 ▲ 1.50% RENT3 30.83 ▲ 1.78% AZZA3 15.12 ▲ 2.44% CSAN3 2.77 — 0.00% RAIZ4 28.00 ▲ 2.56% PCAR3 2.43 ▲ 1.25% GMAT3 3.83 ▲ 0.79% PSSA3 45.65 ▲ 2.93% CVCB3 0.87 ▲ 3.57% POSI3 3.03 ▼ 1.94% SLCE3 17.30 ▲ 4.15% NATU3 5.71 ▲ 10.44% BRKM5 3.02 ▼ 5.63% RANI3 8.76 ▲ 3.44% CSNA3 4.49 ▲ 1.81% IBOV 172,236.05 ▲ 2.22% IPC MEX 72,104.80 ▲ 1.00% MERVAL 2,848,945 — — USD/BRL 5.51 ▲ 0.04% USD/MXN 18.52 ▼ 0.59% USD/CLP 966.96 ▼ 0.99% USD/COP 3,269 ▲ 0.88% USD/PEN 3.41 ▼ 1.07% USD/ARS 1,545 ▼ 0.02% USD/UYU 40.45 ▲ 0.35% USD/PYG 6,450 ▲ 1.45% USD/BOB 11.74 ▼ 0.59% USD/DOP 60.46 ▼ 0.21% USD/CRC 446.56 ▼ 0.38% USD/GTQ 7.64 ▼ 0.05% USD/HNL 26.89 ▲ 0.02% USD/NIO 36.62 — 0.00% USD/VES 897.02 ▲ 0.07% USD/PAB 1.00 — 0.00% USD/BZD 2.00 — 0.00% USD/JMD 157.79 ▲ 2.42% USD/TTD 6.72 ▲ 2.10% EUR/BRL 6.18 ▲ 0.85% BRENT 91.69 ▼ 0.95% WTI 85.87 ▼ 1.13% IRON ORE 161.91 — — COPPER 6.35 ▲ 0.31% GOLD 4,123 ▲ 0.21% SILVER 53.12 ▲ 1.06% SOY 1,190 ▲ 0.61% CORN 440.75 ▲ 0.34% WHEAT 588.75 ▲ 0.13% COFFEE 266.70 ▼ 4.75% SUGAR 18.21 ▼ 0.16% ORANGE JUICE 143.50 ▲ 7.85% COTTON 78.65 ▼ 0.58% COCOA 5,113 ▼ 0.81% BEEF 216.33 ▲ 1.06% CATTLE 324.80 ▲ 0.77% LITHIUM 61.35 ▲ 0.72% PETR4 45.19 ▼ 0.24% VALE3 66.11 ▲ 3.23% ITUB4 41.72 ▲ 2.94% BBDC4 14.68 ▲ 3.38% ABEV3 15.61 ▲ 0.84% BBAS3 17.02 ▼ 0.64% B3SA3 14.85 ▲ 3.20% WEGE3 50.74 ▲ 5.29% PRIO3 59.39 ▼ 1.80% SUZB3 54.20 ▲ 1.50% RENT3 30.83 ▲ 1.78% AZZA3 15.12 ▲ 2.44% CSAN3 2.77 — 0.00% RAIZ4 28.00 ▲ 2.56% PCAR3 2.43 ▲ 1.25% GMAT3 3.83 ▲ 0.79% PSSA3 45.65 ▲ 2.93% CVCB3 0.87 ▲ 3.57% POSI3 3.03 ▼ 1.94% SLCE3 17.30 ▲ 4.15% NATU3 5.71 ▲ 10.44% BRKM5 3.02 ▼ 5.63% RANI3 8.76 ▲ 3.44% CSNA3 4.49 ▲ 1.81%
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Tuesday, November 10, 2026

Covid-19 Brazil

Scientists question need for Covid-19 booster vaccines

By · · 2 min read

RIO DE JANEIRO, BRAZIL – Covid-19 vaccine developers are increasingly asserting that the world will need annual booster vaccines, or new vaccines against coronavirus variants of concern, but some scientists are questioning when, or if, such vaccines will be needed.

Scientists question need for Covid-19 booster vaccines
“We have yet to see the data that would support a decision on whether there is a need for booster vaccines,” said Kate O’Brien, WHO director of the Department of Immunization, Vaccines and Biologicals
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More than a dozen influential infectious disease and vaccine development experts said that there are growing indications that a first round of global vaccinations could offer lasting protection against the coronavirus and the variants of most concern discovered so far.

Some of these scientists expressed concern that public expectations regarding booster vaccines against Covid-19 are being created by pharmaceutical executives rather than by medical experts, but many agreed that preparing for such a need out of caution is prudent.

They fear that pressure from wealthy nations for repeat vaccinations later this year will deepen the gap with poorer countries struggling to purchase vaccines and which may take years to immunize their citizens even once.

“We have yet to see the data that would support a decision on whether there is a need for booster vaccines,” said Kate O’Brien, World Health Organization (WHO) director of the Department of Immunization, Vaccines and Biologicals.

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O’Brien said the WHO is forming a committee of experts to assess all vaccine variant and efficacy data and recommend changes to vaccination programs as needed.

Pfizer Inc chief executive Albert Bourla said people will “probably” need a booster dose of the company’s vaccine every 12 months – similar to the annual flu shot – to maintain high levels of immunity against the original SARS-CoV-2 and its variants.

“There is zero, and I mean zero evidence to suggest that this is the case,” countered Doctor Tom Frieden, former director of the U.S. Centers for Disease Control and Prevention.

“It is completely inappropriate to say that we are likely to need an annual booster, because we have no idea how likely this is,” Frieden, who now leads the global public health initiative Resolve to Save Lives, said of Pfizer’s claims about booster vaccines.

In response to criticism, Pfizer said it believes that boosters are required for as long as the virus is still widely circulating.

This article was produced by The Rio Times’ automated AI newsroom. Editorial responsibility: Matthias Camenzind, Publisher and Editor-in-Chief. The Rio Times also runs Ask Rio Times, which answers from 100,000+ of our own articles, the daily Latin America Power Map, and prediction-market odds on elections and markets.. How we use AI · Report an error

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