IBOV 172,236.05 ▲ 2.22% IPC MEX 71,866.30 ▲ 0.66% MERVAL 2,848,945 — — USD/BRL5.58▲ 1.24% USD/MXN18.69▲ 0.84% USD/CLP977.21▲ 1.03% USD/COP3,287▲ 5.34% USD/PEN3.41▲ 0.11% USD/ARS1,545▼ 0.02% USD/UYU40.45▲ 0.35% USD/PYG6,450▲ 1.45% USD/BOB11.74▼ 0.59% USD/DOP60.45▲ 2.39% USD/CRC446.56▼ 0.38% USD/GTQ7.64▼ 0.05% USD/HNL26.89▲ 0.02% USD/NIO36.62▲ 2.53% USD/VES897.02▲ 0.07% USD/PAB1.00— 0.00% USD/BZD2.00— 0.00% USD/JMD157.79▲ 2.42% USD/TTD6.72▼ 0.03% EUR/BRL6.25▲ 1.86% BRENT 89.56 ▼ 3.25% WTI 84.49 ▼ 2.72% IRON ORE 161.91 — — COPPER 6.25 ▼ 1.17% GOLD 4,058 ▼ 1.37% SILVER 51.77 ▼ 1.51% SOY 1,186 ▲ 0.34% CORN 439.75 ▲ 0.11% WHEAT 586.00 ▼ 0.34% COFFEE 265.40 ▼ 3.00% SUGAR 18.02 ▼ 1.04% ORANGE JUICE 144.80 ▲ 4.66% COTTON 78.30 ▼ 0.61% COCOA 4,860 ▼ 2.88% BEEF 216.33 ▲ 1.06% CATTLE 328.83 ▲ 2.02% LITHIUM 61.35 ▲ 0.72% PETR4 44.68 ▼ 1.13% VALE3 65.20 ▼ 1.38% ITUB4 41.82 ▲ 0.24% BBDC4 14.65 ▼ 0.20% ABEV3 15.63 ▲ 0.13% BBAS3 17.09 ▲ 0.41% B3SA3 14.90 ▲ 0.34% WEGE3 51.64 ▲ 1.77% PRIO3 59.02 ▼ 0.62% SUZB3 54.72 ▲ 0.96% RENT3 30.43 ▼ 1.30% AZZA3 15.04 ▼ 0.53% CSAN3 2.74 ▼ 1.08% RAIZ4 24.40 ▼ 12.86% PCAR3 2.40 ▼ 1.23% GMAT3 3.87 ▲ 1.04% PSSA3 45.81 ▲ 0.35% CVCB3 0.86 ▼ 1.15% POSI3 3.06 ▲ 0.99% SLCE3 16.95 ▼ 2.02% NATU3 5.63 ▼ 1.40% BRKM5 3.03 ▲ 0.33% RANI3 8.46 ▼ 3.42% CSNA3 4.43 ▼ 1.34% IBOV 172,236.05 ▲ 2.22% IPC MEX 71,866.30 ▲ 0.66% MERVAL 2,848,945 — — USD/BRL 5.58 ▲ 1.23% USD/MXN 18.69 ▲ 0.87% USD/CLP 976.65 ▲ 0.97% USD/COP 3,288 ▲ 5.40% USD/PEN 3.41 ▲ 0.02% 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 60.45 ▲ 2.39% USD/CRC 446.56 ▼ 0.38% USD/GTQ 7.64 ▼ 0.05% USD/HNL 26.89 ▲ 0.02% USD/NIO 36.62 ▲ 2.53% 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 6.24 ▲ 1.72% BRENT 89.56 ▼ 3.25% WTI 84.49 ▼ 2.72% IRON ORE 161.91 — — COPPER 6.25 ▼ 1.17% GOLD 4,058 ▼ 1.37% SILVER 51.77 ▼ 1.51% SOY 1,186 ▲ 0.34% CORN 439.75 ▲ 0.11% WHEAT 586.00 ▼ 0.34% COFFEE 265.40 ▼ 3.00% SUGAR 18.02 ▼ 1.04% ORANGE JUICE 144.80 ▲ 4.66% COTTON 78.30 ▼ 0.61% COCOA 4,860 ▼ 2.88% BEEF 216.33 ▲ 1.06% CATTLE 328.83 ▲ 2.02% LITHIUM 61.35 ▲ 0.72% PETR4 44.68 ▼ 1.13% VALE3 65.20 ▼ 1.38% ITUB4 41.82 ▲ 0.24% BBDC4 14.65 ▼ 0.20% ABEV3 15.63 ▲ 0.13% BBAS3 17.09 ▲ 0.41% B3SA3 14.90 ▲ 0.34% WEGE3 51.64 ▲ 1.77% PRIO3 59.02 ▼ 0.62% SUZB3 54.72 ▲ 0.96% RENT3 30.43 ▼ 1.30% AZZA3 15.04 ▼ 0.53% CSAN3 2.74 ▼ 1.08% RAIZ4 24.40 ▼ 12.86% PCAR3 2.40 ▼ 1.23% GMAT3 3.87 ▲ 1.04% PSSA3 45.81 ▲ 0.35% CVCB3 0.86 ▼ 1.15% POSI3 3.06 ▲ 0.99% SLCE3 16.95 ▼ 2.02% NATU3 5.63 ▼ 1.40% BRKM5 3.03 ▲ 0.33% RANI3 8.46 ▼ 3.42% CSNA3 4.43 ▼ 1.34%
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Tuesday, November 10, 2026

Covid-19 Brazil

Covid-19: AstraZeneca vaccine efficacy against Delta variant fades less than Pfizer’s – British study

By · · 2 min read

RIO DE JANEIRO, BRAZIL – The Pfizer/BioNtech vaccine is more effective in fighting Delta coronavirus cases than Oxford/AstraZeneca’s, but its efficacy fades faster, a British study says.

The study established that for high viral load infections, a Pfizer second-dose recipient was 90% more protected against the Delta variant one month before than an unvaccinated individual. The percentage drops to 85% two months later, and 78% three months later.

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In parallel, people administered two AstraZeneca doses are 67% protected one month later, 65% two months later, and 61% three months later.

After four or five months the protection level offered by the two vaccines is similar, according to the study, which is yet to be peer reviewed.

These data “represent a regression” in the efficacy of Pfizer’s vaccine, explained Dr. Koen Pouwels, who took part in the study, while for AstraZeneca’s immunizer, “the differences (between one month and the next) are minimal, meaning there may be no change in protection.”

He insisted that, “despite the slight drop in the level of protection, the overall efficacy (of the two vaccines) remains very high.”

The study coincides with news that several countries, including the UK, are planning to start a campaign for a third booster dose of the Covid-19 vaccine.

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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