A record 5.2 million people globally tested positive for COVID-19 last week, despite the vaccine rollout ramping up in wealthy nations

• More than 5.2 million people globally tested positive in the week that ended Sunday.
• Surges in India and Brazil have contributed to the rise.
• Most COVID-19 vaccines have gone to wealthy countries, and poor nations have struggled to get shots.

More people around the world tested positive for the coronavirus last week than during any other seven-day period, as wealthier nations vaccinate their residents and poorer nations have largely struggled to get shots.

More than 5.2 million people globally tested positive for virus in the week that ended Sunday, led by surges in India and Brazil, per data from Johns Hopkins University. The previous peak was in mid-December. Bloomberg first reported on the news.

The rise in new COVID-19 cases comes after the number of known global coronavirus deaths topped 3 million on Saturday, just three months after hitting 2 million.

The surge in cases highlights a vaccine disparity between rich and poor countries, as Bloomberg estimates 40% of vaccines have gone to just 27 wealthy countries that have 11% of the world's population.

Covax, the World Health Organization's effort to bring shots to poorer nations, had delivered just 38 million vaccines as of April 8. Those vaccines, once administered, would cover less than 0.01% of the world's population. The continent of Africa has received less than 2% of the world's vaccine supply.

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WHO Director-General Dr. Tedros Adhanom Ghebreyesus called to waive patents on the vaccine's formula, which would allow global manufacturers to make the shots at a much faster pace. But big pharmaceutical companies - including Pfizer and Johnson & Johnson - asked President Joe Biden to protect patents on the basis of intellectual-property rights.

India, for instance, is the world's biggest vaccine producer, but it's struggling to get enough COVID-19 vaccines to give to its own population. Only 1.2% of its population, or nearly 16.5 million people, have been fully vaccinated, according to John Hopkins.

The number of new cases added each day in India has risen rapidly since late February. It reported 273,802 new infections on Sunday, a record high for the country, bringing its total to more than 15 million cases - the second-highest in the world.

Brazil reported 461,048 new cases over the past seven days, bringing its case count to nearly 14 million.

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The P.1 variant continues to spread across the country, which researchers say could be twice as contagious as the original and can reinfect people who've already had the virus. Experts think that surging cases of the variant is the reason most COVID-19 intensive-care-unit patients in Brazil are under 40 years old.

About 3.82% of Brazilians have been fully vaccinated, but some scientists said the P.1 variant is developing new mutations that could make vaccines less effective.

Nearly a quarter of Americans, in comparison, are fully vaccinated, and the daily case rate has plummeted since its winter peak, but the country still has the world's highest total COVID-19 case and death counts. The US has recorded more than 567,000 deaths, or more than one-sixth of the global total, alongside almost 31.7 million confirmed cases, per John Hopkins data.