IBOV 171,031.73 ▲ 1.85% IPSA 11,338.38 ▲ 0.89% IPC MEX 65,729.18 ▲ 2.14% MERVAL 2,913,184 ▲ 1.35% COLCAP 2,459.23 ▲ 0.61% BVL PERÚ 58,698.13 ▲ 2.60% USD/BRL5.14▼ 0.14% USD/MXN16.90▼ 0.36% USD/CLP914.28— 0.00% USD/COP3,038▼ 1.18% USD/PEN3.35▼ 0.06% USD/ARS1,499▲ 0.12% USD/UYU40.20▲ 1.58% USD/PYG5,996▲ 1.55% USD/BOB11.43▲ 0.41% USD/DOP58.82▲ 0.20% USD/CRC450.05▲ 3.34% USD/GTQ7.62▲ 2.21% USD/HNL26.81▲ 0.31% USD/NIO36.62▲ 0.61% USD/VES778.00▼ 0.13% USD/PAB1.00— 0.00% USD/BZD2.00— 0.00% USD/JMD 157.28 — 0.00% USD/TTD6.71▲ 0.79% EUR/BRL6.00▼ 0.64% BRENT 88.88 ▼ 0.03% WTI 83.11 ▼ 0.11% IRON ORE 161.91 — — COPPER 6.61 ▲ 0.03% GOLD 4,461 ▲ 1.78% SILVER 65.59 ▲ 1.26% SOY 1,184 ▲ 3.20% CORN 480.50 ▲ 10.02% WHEAT 655.00 ▲ 3.93% COFFEE 317.25 ▼ 5.51% SUGAR 16.43 ▼ 1.79% ORANGE JUICE 138.55 ▼ 0.47% COTTON 85.03 ▲ 2.33% COCOA 5,719 ▲ 3.18% BEEF 223.60 ▼ 3.93% CATTLE 339.10 ▼ 3.16% LITHIUM 75.20 ▲ 1.47% PETR4 41.64 ▼ 0.05% VALE3 72.97 ▲ 0.83% ITUB4 38.60 ▼ 1.03% BBDC4 16.85 ▲ 0.36% ABEV3 14.89 ▼ 0.80% BBAS3 19.37 ▲ 0.47% B3SA3 14.26 ▼ 0.21% WEGE3 47.59 ▲ 0.49% PRIO3 59.14 ▼ 0.19% SUZB3 41.33 ▲ 2.35% RENT3 34.68 ▼ 0.09% AZZA3 15.89 ▼ 2.63% CSAN3 3.22 ▼ 1.83% RAIZ4 0.25 — 0.00% PCAR3 2.75 ▼ 0.36% GMAT3 3.65 ▼ 1.08% PSSA3 48.13 ▼ 0.54% CVCB3 1.33 ▼ 2.92% POSI3 3.36 ▲ 2.44% SLCE3 13.34 ▲ 0.30% NATU3 8.14 ▼ 0.73% IBOV 171,031.73 ▲ 1.85% IPSA 11,338.38 ▲ 0.89% IPC MEX 65,729.18 ▲ 2.14% MERVAL 2,913,184 ▲ 1.35% COLCAP 2,459.23 ▲ 0.61% BVL PERÚ 58,698.13 ▲ 2.60% USD/BRL 5.16 ▲ 0.01% USD/MXN 17.06 ▼ 0.24% USD/CLP 913.98 ▲ 0.04% USD/COP 3,140 ▲ 0.03% USD/PEN 3.36 ▼ 0.66% USD/ARS 1,493 ▲ 0.10% USD/UYU 40.27 ▲ 1.24% USD/PYG 5,939 ▲ 1.68% USD/BOB 11.64 ▼ 0.76% USD/DOP 58.34 ▲ 1.25% USD/CRC 445.92 ▲ 0.89% USD/GTQ 7.62 ▲ 2.21% USD/HNL 26.79 ▲ 1.57% USD/NIO 36.62 ▲ 0.69% USD/VES 762.44 ▼ 0.13% USD/PAB 1.00 — 0.00% USD/BZD 2.00 — 0.00% USD/JMD 157.28 — 0.00% USD/TTD 6.70 ▲ 0.61% EUR/BRL 5.95 ▲ 1.01% BRENT 88.88 ▼ 0.03% WTI 83.11 ▼ 0.11% IRON ORE 161.91 — — COPPER 6.61 ▲ 0.03% GOLD 4,461 ▲ 1.78% SILVER 65.59 ▲ 1.26% SOY 1,184 ▲ 3.20% CORN 480.50 ▲ 10.02% WHEAT 655.00 ▲ 3.93% COFFEE 317.25 ▼ 5.51% SUGAR 16.43 ▼ 1.79% ORANGE JUICE 138.55 ▼ 0.47% COTTON 85.03 ▲ 2.33% COCOA 5,719 ▲ 3.18% BEEF 223.60 ▼ 3.93% CATTLE 339.10 ▼ 3.16% LITHIUM 75.20 ▲ 1.47% PETR4 41.64 ▼ 0.05% VALE3 72.97 ▲ 0.83% ITUB4 38.60 ▼ 1.03% BBDC4 16.85 ▲ 0.36% ABEV3 14.89 ▼ 0.80% BBAS3 19.37 ▲ 0.47% B3SA3 14.26 ▼ 0.21% WEGE3 47.59 ▲ 0.49% PRIO3 59.14 ▼ 0.19% SUZB3 41.33 ▲ 2.35% RENT3 34.68 ▼ 0.09% AZZA3 15.89 ▼ 2.63% CSAN3 3.22 ▼ 1.83% RAIZ4 0.25 — 0.00% PCAR3 2.75 ▼ 0.36% GMAT3 3.65 ▼ 1.08% PSSA3 48.13 ▼ 0.54% CVCB3 1.33 ▼ 2.92% POSI3 3.36 ▲ 2.44% SLCE3 13.34 ▲ 0.30% NATU3 8.14 ▼ 0.73%
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Covid-19 Brazil

Scientists question need for Covid-19 booster vaccines

By · May 13, 2021 · 2 min read

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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.

“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 (Photo internet reproduction)
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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.

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 newsroom system. How we use AI · Report an error

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