A UK trial of the AstraZeneca vaccine on children was halted amid fears of links to a rare blood clot, Oxford University said.

While the researchers insist there are "no safety concerns" in the trial, they said they would wait for additional data from the UK's Medicines and Healthcare products Regulatory Agency (MHRA) before resuming their work.

The trial pause follows a statement from the World Health Organization (WHO) on Tuesday that the "risk-benefit" balance for AstraZeneca's COVID-19 vaccine was still "largely" positive.

"There is no link for the moment between the vaccine and thrombotic events with thrombocytopenia," said Rogerio Pinto de Sa Gaspar, the WHO's director for regulation and pre-qualification.

Previously, an official from the European Medicines Agency (EMA) had claimed there was a "clear connection" between the AstraZeneca vaccine and rare blood clots.

However, EMA's official position remains undecided — the agency said it was still reviewing data and had not reached any conclusion.

Read on for an overview of the latest coronavirus news from around the world:

Americas

Brazil has registered a record number of COVID-related deaths in 24 hours. Health authorities reported over 4,100 deaths on Tuesday, as new variants fuel a surge in cases that has overwhelmed hospitals. 

The total death toll in Brazil is now 336,947, which is second only to the US. 

However, President Jair Bolsonaro has refused to mandate a nationwide lockdown, and opposes local lockdowns, claiming the damage to the economy outweighs health risks.

Economy Minister Paulo Guedes said Tuesday that an accelerated vaccination campaign should get the economy back on track in two to three months. 

Bolsonaro spoke to Russian President Vladimir Putin on Tuesday about buying 10 million doses of Russia's Sputnik V vaccine and producing it domestically.

US president Joe Biden said that all adults in the US will be eligible to get vaccinated against the coronavirus by April 19, moving ahead an original deadline of May 1.

Biden added that while the new strains were more virulent and dangerous, the vaccines would work on "all of them."

Jen Psaki, the White House press secretary, said that there would be "no federal vaccinations database and no federal mandate requiring everyone to obtain a single vaccination credential."

Psaki said that the US government wants to protect the privacy and rights of Americans — signalling that the nation would not opt for a vaccine passport in the future. A form of vaccine passport is currently available in New York 

Mexico's health regulator has authorized the emergency use of COVAXIN, India's COVID-19 vaccine.

"Very timely decision by COFEPRIS to authorize the emergency use of the COVAXIN vaccine manufactured in India. The options for vaccination against COVID-19 in Mexico are expanding!!!," said Marcelo Ebrar, the country's foreign minister.

Asia and Oceania

India's capital New Delhi imposed an immediate night curfew on Tuesday due to a "sudden increase in COVID-19 cases" and a "high positivity rate."

Public movement is banned each night from 10:00 p.m. to 5:00 a.m. local time. Only essential services or people traveling to and from vaccination centers will be allowed on the streets. The measures are set to remain in place until April 30.

India also reported a record number of new coronavirus cases in the past 24 hours — 115,736. The death toll also rose by 630, its greatest increase since November.

The recent surge in cases has brought the average daily number of infections above the previous record of 97,000 last seen in mid-September.

India's government has so far refused to impose a nationwide lockdown, instead asking states to decide on how to impose local restrictions.

South Korea's food and drug safety ministry has approved the Johnson & Johnson vaccine, saying the single-dose shot is safe and effective.

It is the third COVID-19 vaccine to be granted authorization in South Korea, following the BioNTech-Pfizer and AstraZeneca vaccines.

Australia called on the EU to ship out millions of pre-ordered vaccine doses.

Last month, the EU blocked a shipment of some 250,000 doses to Australia on Italy's request. On Tuesday, however, Brussels denied it was blocking over 3 million more doses that were originally set to be exported to Australia.

"We obviously want those millions of doses," Australian PM Scott Morrison told reporters, adding that he read statements that indicated there was no opposition in Europe to exporting the doses. 

Middle East

In Iran, COVID- related deaths have again risen dramatically, as the country has been fully hit by its fourth coronavirus wave. The country logged 193 deaths and 21,954 new infections, according to the Ministry of Health on Wednesday.

The ministry attributed the drastic increase to the easing of restrictions during the two-week Persian New Year vacations (March 21-April 2). During that time, many Iranians were traveling domestically or abroad and did not comply with the government's guidelines.

Strict lockdowns will now be imposed again, with several sectors of the economy, bazaars and shopping malls set to close. Because of the economic crisis, Iran has only been able to import around 2 million vaccine doses. With overall production and availability improving over the coming months, mass vaccinations are scheduled for September.

Europe

Life expectancy across much of the European Union has dropped 2020, as the 27-nation bloc struggled with the impact of the coronavirus pandemic.

“Following the outbreak of the COVID-19 pandemic last year, life expectancy at birth fell in the vast majority of the EU member states,'' wrote the EU statistical agency Eurostat on Wednesday.

The biggest drop was recorded in Spain, with a loss of 1.6 years compared with 2019. Followed by Bulgaria with a loss of 1.5 years and Lithuania, Poland and Romania, which all saw a drop of -1.4 years.

The only nations with positive development were Denmark and Finland, with 0.1 years.

Life expectancy refers to the number of years a person can expect to live. By definition, this is based on an estimate of the average age that members of a particular population group will be when they die.

Italy's government wants to let fans into stadiums for the European Championship football tournament.

Italy's health minister Roberto Speranza told the country's football federation that spectators can attend the football matches at Stadio Olimpico in Rome. Speranza said that this decision was based on protocols from advisers.

The decision to allow spectators in stadiums comes as Italy gears up to restart tourism to the country this summer.

Poland will extend it’s COVID-19 restrictions until April 18. Kindergartens, shopping centers, hotels, cinemas and theaters will remain closed. Authorities fear the post Easter effect could aggravate the country’s struggles to cope with a third wave of infections.

Health Minister Adam Niedzielski said that the consequences of increased mobility during the Easter weekend would be evident in next week's statistics, and that an increase in case numbers was possible.

The situation in Poland is similar to it’s neighbor Germany. With a similarly low vaccination rate, the health service has been pushed to the brink.

Global

About one in three people who survive COVID-19 suffer from neurological or psychiatric problems six months after diagnosis, according to a study in medical journal, The Lancet. According to the research, COVID-19 patients were also more likely to develop brain conditions.

This is the largest study to date covering the psychological impact of COVID-19 on survivors. About 230,000 recovered patients were surveyed, of whom 34% were diagnosed with a neurological or psychiatric issue.

About 17% of patients had anxiety, while 14% reported mood disorders. The risk for brain disorders was higher in patients who had had a severe case of COVID-19.

Norwegian Cruise Line, the third-largest cruise line in the world, said that it would resume trips beginning in July for passengers who have received the full dosage of the coronavirus vaccine.

The cruise operator said that on July 25 it would gradually resume cruises on new routes in Greece and the Caribbean.

Norwegian said that it would have "medical-grade air filtration" on board as well as sanitation measures and "enhanced" medical resources.

wmr, am/dj (AFP, AP, Reuters, dpa)