I'm John Macintosh with the BBC News. Hello.

Researchers in the United States have warned that it could take a decade for a vaccine against the Zika virus to be made available. Scientists at the University of Texas say most of the time will be taken up in securing regulatory approval. They say the mosquito-borne virus has been linked with impaired brain development in the womb. Dr. Mark is the Head of the Pan American Health Organisation.

The priority is to aggressively control the vehicle. This is not Ebola. This virus needs a vehicle to be transmitted. And it's a mosquito. If countries pick up the garbage, if countries are educating people about covering the waters, the containers, because that's where the mosquitoes breed, then they may be able to minimize massively the impact of this virus in women.

Reports from Sweden say the country intends to expel up to 80,000 failed asylum-seekers who arrived last year. The Interior Minister, Anders Ygeman, has reportedly asked the police authorities in charge of migrants to organise the planned expulsions. It's thought they are likely to take several years to carry out. Sweden accepted a record number of migrants last year. The authorities say there's been a big increase in the number of threats and violent incidents at reception centres.

The British government has announced that it will take in more unaccompanied children from refugee camps near Syria. They will (be) all in addition to the 20,000 Syrian refugees who are due to be resettled in the U.K. over the next five years. Kerry Walker reports.

The government's been under pressure from charities and opposition parties to accept 3,000 refugee children as part of its response to the migrant crisis. Now, the Immigration Minister, James Brokenshire, has asked the U.N. High Commissioner for Refugees to identify unaccompanied children and help to bring them to the U.K. But they'll come from the countries neighbouring Syria, not from among the one million refugees who've arrived in Europe. And the government has not put a figure on how many it will take.

The social media company, Facebook, has announced a big increase in earnings and profits that doubled in the last quarter of 2015, compared to the same period in the previous year. The Chief Executive, Mark Zuckerberg, said the business was thriving. Dave Lee reports.

You'd be hard pressed to find a more content person in the whole of Silicon Valley. Mark Zuckerberg, fresh back from maternity leave, finds his company in rude health. This is the tenth time in a row that Facebook has exceeded investors' expectations for both growth and profit. And that success is down to the site being able to offer advertising that works on people using Facebook on their mobile phones. Shares rose by nearly 10% after adding on the expectations that things will only get better from here. The company is making big strikes in new areas like video and virtual reality.

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Sudan's state media says the border with South Sudan is to be open for the first time since the South declared independence five years ago. The decree by President Omar al-Bashir follows the decision earlier this week by South Sudan to pull its army back from the border and send a special envoy to the Sudanese capital, Khartoum, to promote the normalization of ties. Sudan closed the border in 2011, accusing the South of supporting rebels in the north.

At least three female suicide bombers are reported to have been involved in an attack in the Nigerian town of Chibok, which killed thirteen people. More than thirty people were injured in the blasts, which occurred at a military checkpoint and a market. Chibok was home to more than two hundred schoolgirls who were kidnapped by militants from the Islamist Boko Haram group two years ago.

Thirty-one countries have signed an international agreement, designed to stop multinational companies using complex tax arrangements to avoid paying tax. The agreement, signed at the Organisation of Economic Cooperation and Development in Paris, will mean countries sharing tax information. The deal was hammered out at a meeting of the G20 last year. Critics say it doesn't go far enough.

A computer programme has beaten a professional player at the popular Chinese game Go, for the first time. The programme, AlphaGo, won five games in a row against the European champion. Players used black and white pieces, vowing to take control of territory on a wooden checker board. Demis Hassabis is one of the founders of DeepMind, the London Artificial Intelligence Company which developed the programme.

Before the match, we suspected we might be stronger than him. But we obviously didn't know, because we didn’t entirely test it against their own test systems, and of course, it was a historic moment. So it was a fantastically exciting game, actually. It was a very close game. And I guess it was a mixture of relief and amazement and excitement when we did actually win.

That's the BBC News.