Young children sit on the laps of medical staff, watching intently as a briefing describes the dangers of Ebola. Foreigners and citizens arriving at the capital’s airport are held in quarantine for weeks. Tourists are banned outright.

The world’s most draconian measures against the disease have been imposed not in the worst-affected west African countries, nor their neighbours, but in North Korea, thousands of miles from the outbreak.

They are increasing the isolation of a country already known for its tight controls on contact with outsiders, and risk damaging its fragile economy.

The Guardian was among the small number of foreigners allowed to fly in after the ban on tour groups but before the imposition of quarantine on all those entering from abroad. The fear is tangible; a factory and a research centre which journalists were due to visit cancelled the invitations, citing Ebola concerns.

“It’s Ebola hysteria,” said one foreigner in the country. “People are really scared.”

Each night, the country’s television news broadcasts a lengthy section on the disease, filling the screen with images of grieving families, ailing patients and medical workers in protective gear – as well as some coverage of its own measures, including footage of the session at the children’s hospital.

On Friday the state news agency KCNA announced in a one-sentence news report: “A brisk hygienic information service goes on in the Democratic People’s Republic of Korea to prevent the outbreak of Ebola.”

But the news bulletins appear to have alarmed rather than reassured many North Koreans.

“People are asking foreigners for information; they don’t understand Ebola and don’t really know what it is,” said a westerner in the capital.

At Pyongyang’s airport, groups of uniformed soldiers toiled at “Korea speed” – a zealous pace – to complete the gleaming new building that will soon replace the small, dingy terminal. It is evidence of the country’s recent push to attract more international visitors, like the kitschily accomplished aquatic performances at the capital’s dolphinarium, and the sizeable Mirim Riding Club, where tourists can trot around a sawdust-strewn arena with a trainer for $40 (£25). Both are lauded as projects for the people, but promoted to foreigners.

Those plans to expand tourism – earning precious foreign currency – are now on hold indefinitely. The Yanggakdo Hotel, one of the few hotels in Pyongyang where foreigners may stay, was largely deserted, though some Chinese business travellers and a handful of westerners remained. Chinese croupiers in its casino said they had seen few guests.

Some believe the stringent Ebola measures reflect the state’s enduring suspicion towards the outside world, even as it tries to benefit from contact. Others think the real causes are more prosaic, citing the poor state of the country’s health system and the adoption of similar measures when the respiratory disease Sars hit the region in 2003.

“I understand the logic of what they are doing, even if it seems extreme. They don’t think they can control any outbreaks of anything like that and with Sars and avian flu they developed what for them are now standard operating procedures,” said Hazel Smith, an expert on North Korea at the University of Central Lancashire.

“If there was someone with Ebola coming in, it wouldn’t be easy to avoid contagion: they have problems with electricity, running water and disinfectants.

“Sars was close and they were one of the few countries in east Asia that avoided it. They think this approach has proved successful in the past; the question of whether [Ebola] is relevant to them is another matter.”

She noted that there had been intense debates in other countries over what precautions were appropriate. Australia and Canada have introduced visa bans on people from Guinea, Liberia and Sierra Leone, the countries worst affected by Ebola. Other countries have introduced screening for travellers arriving from those places. But none has taken measures even approaching those in North Korea.

The country announced it was banning all tour groups on 23 October. It also began refusing entry to citizens of countries that had had Ebola cases: a Beijing-based Spanish cameraman was told he could not make a scheduled trip.

Two individuals from African countries – both far from the outbreak zone – were ordered into quarantine after arrival in Pyongyang, though one has since been allowed to leave.

An unknown number of North Korean citizens who have returned from abroad have also been quarantined, although it is not clear if the measure applies to all countries or specific ones. North Korea has diplomatic ties with Liberia, Guinea and Sierra Leone.

Kim Yong Nam, the head of the country’s parliament, has been touring Africa, visiting Sudan, the Democratic Republic of the Congo, Uganda and Ethiopia with other senior officials including the minister of public health.

On Thursday the country tightened measures further, announcing that all foreigners entering the country would have to undergo a three-week quarantine period.

Foreign visitors who entered in the days before the quarantine announcement were told that daily temperature checks were compulsory.

The DailyNK website, which relies on sources inside the country, has also reported internal travel restrictions preventing many North Koreans from visiting the capital and requiring others to obtain a health certificate before making the journey.

“It’s very much a trade-dependent economy, and especially trade with China now is absolutely crucial for the daily life of citizens at every level of society,” warned Andray Abrahamian, executive director of Choson Exchange, a non-profit organisation helping North Koreans to help develop their understanding of business and economics. “To have that cut off for even a few weeks would be debilitating.”

However, he added that exemptions were likely almost immediately, especially for Chinese citizens with multiple entry visas. “The people who do have contacts with Chinese businesspeople can get the message flowing upwards that this is seriously damaging to the economy.”

Smith said: “North Korea is completely different from 10 years ago. There are powerful push factors that will ensure important economic exchanges will continue. The last thing they want is to stop major commercial interchange. All the elite have big commercial interests.”

When it came to smaller-scale trade, officials no longer had full enforcement capacity in Chinese border areas, she added: “There will be bribes and people slipping backhanders to get people in.”

Associated Press said on Friday that Chinese businesspeople on the border had said they were unaffected and China’s state news agency, Xinhua, reported that no Chinese nationals had been quarantined.

Already, officials have said that diplomats and the staff of international organisations – who have to make regular trips to Beijing for cash and other supplies because of sanctions – can serve their quarantine at home rather than at designated quarantine hotels. That is a relaxation of the Sars rules.

Those in the tourism industry say thousands of westerners and perhaps a few hundred thousand Chinese visit North Korea each year, as well as many Malaysians and Singaporeans. Summer is the peak time for visitors, but several upcoming tours have been hit.

“The best guess anyone has is that this will last for the rest of this year – and after that we will see,” said Simon Cockerell, general manager of Koryo Tours, which has already cancelled one trip.

“If Ebola subsides, they can open up the country and say, ‘We got it right’,” said Gareth Johnson, managing director of the firm Young Pioneers, which had several tours booked this winter. “The problem is that if it gets any worse, or there’s an Ebola case in China, they will feel they cannot open up again.”