Spain to test 30,000 families for the coronavirus

With more than 90% of cases going undetected, the government is aiming to get a more accurate picture of the spread of the virus and from there decide how to ease the confinement measures

A health worker tests a police officer for Covid-19 in Madrid.
A health worker tests a police officer for Covid-19 in Madrid.RAFA ALBARRAN / AFP

At least 15 of every 16 people infected with the coronavirus in Spain – more than 90% – have not been officially registered, according to estimates from the Spanish Health Ministry. The majority of experts agree that the number of people who have had the SARS-CoV-2 virus is much higher than the official number of 140,510, the latest figure released on Tuesday by the Spanish government, and some studies even suggest that the real amount could stretch into the millions.

The Health Ministry has announced that it is going to carry out a mass testing campaign in order to get a more realistic picture of the spread of the coronavirus and to combat the epidemic. The plan, which has been designed by the Carlos III Health Institute (ISCIII), is to test around 30,000 families – some 62,400 people – during a campaign that will begin next week and last three weeks, according to the health minister, Salvador Illa. The aim is to analyze the gap between the official figures and the real spread of the virus and from there design measures that will offer a way out of a crisis that has so far cost the lives of 13,798 people in Spain, according to the official figures.

José Martínez Olmos, the former general secretary of the Health Ministry and a professor at the Andalusian School of Public Health, says that around 5% of the population is likely to have been infected with the virus. “Although no doubt it will be more,” he adds. He calculates that the national average could be as high as 15%, with the hardest-hit areas such as Madrid with up to 40%, and others, such as Huelva, which has not been greatly affected by the epidemic, as low as 4%.

If the 5% figure is accurate, this would mean that at least 2.35 million people are, or have been, in contact with the coronavirus, which is 15 times more than the official figure. This would be logical, given that the official figures only include cases of people who have been infected and have displayed symptoms, while the majority of those infected – around 85% of the total – are not even aware that they have the coronavirus.

Once the testing has been carried out, the government can begin to decide which confinement measures can be lifted and how. “It’s about getting as accurate a picture as possible by zone and with the greatest representation by gender, location… The ideal thing would be to have it neighborhood by neighborhood,” Martínez Olmos explains.

According to a document from the ISCIII, to which radio network Cadena SER has had access, a rapid test will be carried out on each member of a household, and if it comes back negative, a more reliable PCR test will be carried out. The process will be repeated after 21 days.

At least 15 of every 16 people infected with the coronavirus in Spain – more than 90% – have not been officially registered

The sample of the population will exclude senior residences and other institutions, with the aim of obtaining representative data on a national, regional and provincial level, as well as a range of ages.

After the tests are carried out, if there are infected members of a household a decision will be taken whether or not to isolate them, whether that be in a room in their own home or in a public installation. At the weekend, Spanish Prime Minister Pedro Sánchez requested that the country’s regional premiers put together a list of infrastructures that can be used to isolate positive cases who do not need hospital treatment, so that they do not infect those near to them.

The government explained on Monday that the confinement in cases where there are no symptoms would be voluntary, but said it was seeking legal formulas to deal with those people who do not want to be isolated.

In order to select the households that will participate, the ISCIII will need the help of Spain’s National Statistics Institute (INE), while the regions will be involved in the rapid testing and the PCR tests. Healthcare professionals should not be needed for this process, given that a pinprick test is all that is required for the test, similar to those carried out by diabetics to test their blood sugar levels.

While the study will be voluntary, the ISCIII is expecting a high level of participation given the social awareness of the effects of the crisis. “All of the tools to carry it out quickly are being put in place,” said on Tuesday María José Sierra, from the Health Ministry’s Coordination Center for Health Alerts.

Up to 5% of the Spanish population is likely to have been infected with the virus, according to some estimates

Idelfonso Hernández, a public health professor at the Miguel Hernández University in Alicante, points to the importance of carrying out this testing before taking decisions on the current isolation measures in place, given that it will offer a picture of how many people are still susceptible to infection.

Martínez Olmos adds that there will need to be common rules to relax the isolation measures, but they will have to be adapted to each environment. For example, minimum distances between people of one meter can be established. But if in Madrid, 40% of the population is found to have been infected – and as such have immunity, albeit of an as-yet undetermined length – restaurants could be reopened if they respect this safe distance. This decision could be delayed in areas with low rates of infection, given the greater risk to the population due to lower immunity levels. The same process would be implemented with theaters, cinemas and other areas that attract crowds, and which would not be opened during an early stage of relaxing the confinement measures.

The government is for now planning to repeat the initial test after 21 days, although an ideal scenario would see periodic testing so that decisions can be taken according to the situation at any given time. The fact that the health system is only registering infections among those who have symptoms, are hospitalized or are taken into intensive care, and the fact that the virus can be transmitted by people who are asymptomatic, means that this mass testing is crucial to combating the epidemic.

English version by Simon Hunter.

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