Highest coronavirus infection rate is now among children, but figures in Spain are falling for all ages

Experts consulted by EL PAÍS believe this is most likely due to this age group being the only one that is unvaccinated. Pfizer has this week announced good results from its vaccine trials for five- to 12-year-olds

Children returning to school after the summer break in Murcia last week.
Children returning to school after the summer break in Murcia last week.Marcial Guillén (EFE)

Viruses circulate among the population like lava on a hillside: they seek the best routes to continue on their journey, those where there are fewer obstacles in the way of their progress. The under-12s, the only group in Spain that is not included in the ongoing vaccination campaign, has now become the segment of the population where the coronavirus is circulating most. That said, its propagation is falling in all age groups, including this one. The cumulative incidence among the youngest people in Spain was, according to the latest Health Ministry report, 123.3 cases per 100,000 inhabitants over the previous 14 days, while the average for the whole of Spain came in at 83.4.

Pediatricians and epidemiologists all point to the fact that the most likely reason why the youngest residents of Spain currently have the highest incidence is because they are the only collective yet to be offered the vaccine. The return to school would not yet have had an effect on the data, given that there has barely been time for infections in the classroom to be reflected in the statistics. For the under-12s, there are still no approved vaccines, although pharmaceutical company Pfizer did announce on Monday that its trials show that its formulation is as effective for children aged five to 12 as it is for older age groups. The study that backs this claim is yet to be published, and will have to be revised by regulatory agencies (first in the United States and then in Europe) before official approval is granted.

Federico Martinón, chief of the pediatric service at the Hospital Clínico Universitario in Santiago, and a vaccine consultant for the World Health Organization (WHO), explains that there could be a number of circumstances as to why the highest rate of infections is being registered among children. “It’s difficult to interpret,” he says. “I’m not surprised that there are more infections among those who aren’t vaccinated, and even more so in summer, when there was greater circulation of the coronavirus and children were infected in the home, coinciding with the relaxation of the rules in their immediate environment, and were probably infected by their parents.”


We could be diagnosing a lot of Covid cases because we are actively seeking them
Federico Martinón, chief of the pediatric service at the Hospital Clínico Universitario in Santiago

With the start of the new school year, the current protocol states that any child with respiratory symptoms is tested for the coronavirus. “We could be diagnosing a lot of Covid cases because we are actively seeking them,” he adds. “I would not blame schools for anything, certainly not so soon [after the start of classes]. On the contrary, if everything goes like it did last year, we will have a reduction in this group of SARS-CoV-2 and other seasonal infections.”

Quique Bassat, an epidemiologist from the Spanish Pediatric Society, believes that it is to be expected that the virus would be circulating the most among children given that they are the only unvaccinated group. “I am following cases in schools and there is not a large number being reported, although we have only had a week of activity,” he says.

Francisco Álvarez, an expert in vaccines from the same society, says that this higher circulation among children was also seen this summer in the United States. That said, the vaccination rate in that country is much lower among other age groups than it is in Spain. Álvarez confesses that it is not known exactly how the virus will behave among children in the coming weeks.

In Spain, the month of September has seen not only the start of the new school year, but also the return to the office for many staff who have until now been working from home. Despite this restarting of activity, the curve of infections is still falling among all age groups according to the latest Health Ministry report. This is also the case for children, but the descent is somewhat slower. A faster fall is being seen among adolescents and young adults, who were at the center of the massive spike in cases that was seen at the outset of the summer as the school year came to an end and restrictions were lifted, prompting increased social contact among these groups.

Experts are closely monitoring the data for any change in trend that could represent the start of a sixth wave of the virus in Spain

In general terms, the incidence is lower the higher the age group. Among 20- to 29-year-olds, the 14-day cumulative number of coronavirus cases per 100,000 inhabitants is at 87.7. For the 30-39 group it is 87.1; for 40-49 it is 82.6; it falls to 66.1 for 50-59; 63.6 for 60-69; and 63.7 for 70-79. For the over-80s, the incidence is slightly higher, at 89.1 cases per 100,000 inhabitants.

Experts are closely monitoring the data for any change in trend that could represent the start of a sixth wave of the virus in Spain, but they almost unanimously agree that it would not be anything like the others. With the majority of the Spanish population fully vaccinated – the figure was 75.9% on Monday, more than 36 million people – hospitals are much less likely to be put under the same kind of pressure as they were before the vaccination campaign had advanced. During the fifth wave at the outset of summer, which began with just a third of Spaniards fully vaccinated, most hospitals were able to continue with their regular activity and the death rate of the virus was seven times lower than it was during the rest of the pandemic. It is to be expected that the data will be even better during any future spikes in infections, given the progress of the vaccination campaign.

A step closer to a vaccine for children

The announcement by Pfizer of the good results for its children’s vaccine is bringing the opportunity to inoculate this group ever closer. While the authorization from health agencies is still pending, until now these bodies have approved all of the announcements that the pharmaceutical company has made related to its Covid-19 vaccines. The likely scenario is that between the end of October and the start of November, the US and European authorities grant authorization for its use.

That, however, does not mean that children will automatically receive their shots. In the case of Spain, the government will await the decisions of the European Medicines Agency. Once this body has granted its approval, the board of vaccine experts that is advising the Inter-Territorial Council of the National Health System (CISNS), which brings together the central Health Ministry and the regions, will have to make a final decision on whether or not to recommend the vaccines for children. Among this youngest age group, there is a very low risk of serious illness or death due to Covid-19, meaning that the benefits of the vaccine are not as clear as they are for adults.

According to the latest data from the Carlos III health institute in Madrid, since the pandemic began in Spain, a total of 3,259 children aged under 10 have been hospitalized, which is one for every thousand diagnosed. Meanwhile, 170 have required intensive care treatment, and 16 have died due to Covid-19.

In its Monday report, the Health Ministry reported 5,988 new coronavirus infections detected over the weekend, and added 118 Covid-19 fatalities to the overall death toll. Since the pandemic began, there have been 4,935,534 official infections and 85,901 deaths.

English version by Simon Hunter.

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