Just 5 per cent of Spaniards have been infected by coronavirus and “herd immunity” against the pandemic is a much more distant prospect than some had hoped, a government-backed report indicated on Wednesday.
Preliminary findings in a high-profile national survey, based on antibody tests, suggested about 2m of Spain’s 47m inhabitants have contracted the virus, although infection rates in Madrid and the surrounding provinces in the centre of the country were much higher, at 10-14 per cent.
Salvador Illa, Spain’s health minister, said the findings confirmed the government’s expectations and its cautious, staggered phase-out of the country’s tough two-month lockdown.
However, the results, based on tests on more than 60,000 people across the country, are particularly significant because of the widespread hope that a large number of people in nations such as Spain are at least temporarily immune to the virus because they have contracted it without being tested or perhaps even displaying symptoms.
If a sufficiently big proportion of the population was immune to the virus — about 60 per cent — a country as a whole could develop “herd immunity” and so be relatively protected against a coronavirus second wave, which is widely feared in the autumn if not before.
Spain has been one of the countries worst-hit by the pandemic, with over 27,000 documented deaths and an official tally of more than 228,000 cases. But Mr Illa said the results of the survey showed “there is no herd immunity”.
The study will continue with two further rounds of tests of its participants. It found infection rates were much lower among children, and that 26 per cent of those people who had been infected had been asymptomatic. Infection rates for men and women were roughly the same.
The survey’s findings contrasted with an influential report by Imperial College that estimated a mean average of 15 per cent of Spaniards — and perhaps as much as 41 per cent — had been infected as of March 28.
However, it was in line with research last week by the Italian Institute for International Political Studies that put the Spanish infection rate at 4.9 per cent. The Institute’s research, based on figures from European governments, indicated Belgium has the highest percentage of citizens with some degree of potential immunity in Europe, with 6.4 per cent, while the figure was 4.4 per cent for Italy, 3.8 per cent for the UK and only 0.7 per cent in Germany.
The World Health Organisation’s chief scientist on Wednesday said there was “still a long way to go” for herd immunity.
Soumya Swaminathan told the FT’s Global Boardroom digital conference that rates higher than 10-20 per cent had not been observed anywhere in the world, with New York City probably representing the highest to date with 20 per cent.
She added: “A vaccine is the best way to achieve quick herd immunity . . . without paying the price of [a large number of] deaths — which you would have to accept if you would go for a more natural herd immunity approach.”