A version of this story appeared in the April 14 edition of CNN’s Coronavirus: Fact vs. Fiction newsletter. Sign up here to receive the need-to-know headlines every weekday.

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Confusion is growing over the safety of the Johnson & Johnson Covid-19 vaccine, after use of the shot was paused in the United States with little warning, catching President Joe Biden off guard and sending state leaders scrambling to stop shots going in arms.

It was after 10 p.m. on Monday that officials leading Biden’s ambitious vaccine effort received the news that the US Food and Drug Administration (FDA), with the US Centers for Disease Control and Prevention (CDC), was preparing an announcement for the following morning concerning J&J’s vaccine. Because details were so scant, White House officials didn’t brief the President, according to two people familiar with the situation, write Kevin Liptak, Kaitlan Collins and Kristen Holmes.

Six women in the US have experienced a rare combination of cerebral venous sinus thrombosis – clotting in the sinuses that drain blood from the brain – and low levels of blood platelets following the single-shot J&J vaccine, which has been given to almost 7 million people. One of those cases has been fatal, making the incidence of the blood disorder and fatality rate extremely low. The combination of clots and low blood platelet counts is the same condition reported in dozens of people in Europe who had received the AstraZeneca vaccine.

The early morning alert Tuesday set off a scramble in states that were preparing to administer the J&J shot within a matter of hours, forcing administration health officials to deal with frustrated governors in a midday call. New Hampshire Gov. Chris Sununu, a Republican, asked if there was something driving the decision other than the six cases, complaining it was difficult to explain a pause over something so rare.

“What has to be appreciated is the ability for governors to reinstill confidence after something like this is 100 times harder than the pause in the first place,” he told federal officials on the call.

Meanwhile, J&J has paused its vaccine rollout in Europe, as the European Medicines Agency (EMA) said it was closely monitoring developments around the shot in the US. EMA confirmed a “possible link” between the AstraZeneca Covid-19 vaccine and the same combination of blood clots and low platelet counts last week, but it stopped short of advising countries to limit its use.

YOU ASKED. WE ANSWERED.

Q. If I am young and healthy, then why should I take the vaccine?

A. Millions of Americans took flights this week, but the Centers for Disease Control and Prevention (CDC) is still urging people to avoid non-essential travel, even if you’ve been fully vaccinated, because the majority of Americans have not had their shot yet.

But there are some symptoms that can indicate blood clotting that you should look out for. If you experience a severe headache that doesn’t go away, significant abdominal or leg pain that doesn’t subside, or increasing shortness of breath, health officials say you should call your doctor immediately. All six cases reported were in women between six and 13 days after having the vaccine, but if you’re a man and are experiencing these symptoms, you should still call your doctor. If you received the J&J vaccine more than a month ago, the risk of experiencing a serious blood clot is very low, CDC officials say. Read here for more details.

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WHAT’S IMPORTANT TODAY

Walensky’s comments followed her statement last week that racism is a public health epidemic.

The fallout from the Covid-19 pandemic is poised to fracture societies worldwide, increase instability across the globe and reshape political and economic realities for years to come, the US intelligence community warned in a stark report laying out the top security concerns facing the country.

The dire economic picture boosts the risk of internal conflicts, surges in cross-border migration and even the collapse of national governments, officials warned. The report, known as the Annual Threat Assessment, is typically made public once a year, but bitter wrangling between the Trump administration and Congress kept the 2020 document locked away.

The Olympics is in 100 days. It might become a super-spreader event.

When volunteers for the 2020 Tokyo Olympics have asked officials how they’ll be protected from Covid-19 recently – given the foreign athletes pouring into Japan for the event and the country’s low vaccination rate – the answer has been simple: They’ll get a small bottle of hand sanitizer and two masks each.

With 100 days to go and just 1% of Japan’s population vaccinated, questions remain over how Tokyo can hold a massive sporting event and keep volunteers, athletes, officials and the Japanese public safe from Covid-19, Blake Essig, Emiko Jozuka and Ben Westcott write.

Deaths outpace births in some Brazilian cities as Covid-19 surges

For the sixth month in a row, the city of Rio de Janeiro has seen more deaths than births – a devastating indicator of Brazil’s unceasing Covid-19 crisis. The nation’s second most populous city registered 36,437 deaths in March, 16% more than the month’s 32,060 new births. It wasn’t alone: At least 10 other Brazilian cities with populations over half a million people also registered more deaths than births last month.

The grim death-birth ratio is one more lens onto a national crisis that federal and local officials have largely failed to contain more than a year into the pandemic, Rodrigo Pedroso and Caitlin Hu write. Cities across the country have been hit hard by a recent surge in Covid-19 cases and deaths, fueled in part by new variants believed to be more contagious than older ones, as well as some Brazilians’ disregard for social distancing precautions.

ON OUR RADAR

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TODAY’S TOP TIP

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TODAY’S PODCAST

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