Falling Covid cases in Spain’s schools lead experts to believe herd immunity is near


Fears that were rife in Spain a month ago ahead of the return to school of 5.2 million students under the age of 12 have now made way for optimism. A possible rise in infections among the only group of the population that has not been vaccinated against Covid-19 has not come to pass, and experts are starting to consider that the levels of protection reached – nearly 80% of the Spanish population has been fully inoculated – have brought Spain to a situation that is nearing something resembling herd immunity. While the total eradication of the virus is not expected, the experts consider that the moment when students aged over six in elementary schools will no longer have to wear face masks is not far away.

“We are in the best of the scenarios that we could have expected a month ago,” explains Quique Bassat, an epidemiologist and researcher at the ISGlobal institute in Barcelona. “Community transmission has fallen a lot and very fast, and this, together with the protection measures that have been maintained in schools, has been sufficient even with a variant that’s as contagious as delta,” he explains, in reference to the strain that first was detected in India and has now become predominant.

Jesús Rodríguez Baño, the head of infectious diseases at the Virgen de la Macarena Hospital in Seville, shares this view. “If we have to look for an explanation for why the epidemiological situation is improving in a sustained manner, and is also doing so among those who are unvaccinated, given that the delta variant is circulating and we are gradually returning to normal, the only plausible one is that something similar to that concept of herd immunity is already working,” he says.

The daily report from the Spanish Health Ministry provides the data that support these hopes, only tempered by the “necessary precautions that must be maintained when faced with a virus about which we still don’t know things like how long immunity lasts,” as Rodríguez Baño explains. The 14-day cumulative incidence was, in Thursday’s ministry report, at 40.5 cases per 100,000 inhabitants, a third of that registered a month ago. This trend has also been seen among the under-12s, for whom the incidence has fallen from 150 to 60 this month. The fall has been even more abrupt – from 154 cases to barely 30 – among the 12-19 age group, 80% of whom have already been fully vaccinated against Covid-19.

If these data are compared to a year ago, when the second wave began to take shape, the differences are stark. The incidence then was in excess of 250 cases per 100,000 inhabitants, there were 11,300 Covid-19 patients in hospital and 1,600 ICU patients. In Catalonia, for example, a year ago there were 1,500 classes confined – now there are just 100.