A few weeks ago, people in Madrid started to notice a sudden increase in the number of new flats to rent long term on real estate agency websites.

Something else was odd too: many of those new ads were of apartments in the city centre and other touristy areas, and included pictures of surprisingly high quality that showed towels nicely folded as rolls on the bed and fully set kitchen tables – not what one usually finds when looking for a new flat.

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Instead, the new postings looked strikingly similar to those usually found on Airbnb and other short-term and tourist rental platforms.

So much so that they were in fact apartments until then offered only at daily rates on Airbnb.

With tourism and travelling brought to a halt by the Covid-19 outbreak, landlords and property managers seemed to be moving their apartments from paralysed tourist rental platforms to the long-term market.

It wasn't just in Madrid.

The same was happening in Barcelona. And in Dublin. And in Edinburgh. And in London. And probably in more European cities, while the same trend has been reported in other world regions.

Activists and advocates for the right to housing for years have denounced the impact Airbnb and other short-term rental platforms are having on the housing markets of many European cities.

They argue that taking apartments off the long-term market and renting them out to tourists and visitors reduces the offer and thus increases the price of long-term rentals and adds to the phenomenon of gentrification.

According to that view, short-term rental platforms help turn housing into a financial asset to be exploited for profit, rather than it being a social good providing people with homes.

The total number of listings on Airbnb stands at over 7 million now, but the company does not publish detailed data that would allow to track the increase in that number over time.

However, according to research published last December there was a rise of 20 percent in the number of "active listings" on Airbnb between October 2018 and September 2019, from 3 million to 3.6 million (active listings refer to those that received at least one review during those months).

In that period, the number of apartments listed as active on Airbnb in Greece grew by 25 percent, and by more than 20 percent in Portugal and Spain.

Official line

Airbnb's official line is that it is part of the so-called sharing economy, and that it helps people make some extra money, or even make ends meet, by allowing them to rent out an extra room every now and then.

However, in Dublin and Barcelona around 49 percent of listings on Airbnb are whole apartments, while in London (56 percent), Edinburgh (62 percent) and Madrid (67.1 percent) it's more than half, according to the most recent figures by Inside Airbnb, which compiles and analyses data from the rental platform.

And academic research has shown a causal relationship between the spread of Airbnb-listed apartments and the expulsion of long-term residents from their neighbourhoods in cities like Lisbon and Barcelona.

Housing activists and advocates see the indications that landlords and managers are currently moving property from Airbnb to the long-term market as further proof that tourist and short-term rental platforms help turn housing into a financial asset to be exploited for profit, and they assume those apartments will go back to the tourist market as soon as they become profitable once the coronavirus crisis is over.

From its side, Airbnb has launched a global programme to help its hosts "house more than 100,000 Covid-19 healthcare staff and first responders", and is reportedly considering postponing its move to become a publicly-traded company from this year to 2021.

For the last years, municipalities in Europe have been trying to regulate how Airbnb and other short-term rental platforms can operate in their cities, but last December the European Court of Justice made that harder by ruling that Airbnb acts as an "information society service", and it can't be regulated the way real estate agencies or other housing services are.

Housing has become one of the main lines of defence against the current Covid-19 outbreak as we all are told to stay home. With governments now enacting all types of extraordinary measures to tackle the pandemic, and companies and people trying to cope with the public health and economic emergency as best as they can, it remains to be seen how authorities, corporations, landlords and residents will regard housing in the post-coronavirus world we are heading into.