María del Mar Mosquera: "Anti-vaxxers don't get measles because vaccinated people protect them."

BarcelonaMaría del Mar Mosquera (Ourense, 1967) is a microbiologist at Hospital Clínic and a measles expert. She is one of the people who participated in the development of the Ministry of Health's plan for the elimination of measles and rubella and works in the laboratory that analyzes the large volume of suspected contagion samples in Catalonia. She reviews the current situation of the disease in Catalonia and Spain following the outbreak in Garraf with ARA.

We have had a continuous increase in cases for three years. Is there a risk that the disease will once again become endemic in Spain and that the measles elimination status achieved in 2016 will be lost?

— Not at the moment. The situation in Spain is very good compared to other neighboring countries, such as Morocco, France, the United Kingdom, and other European countries. This is thanks to the high percentage of vaccinated people. Outbreaks like the ones we're seeing can occur without losing the state of elimination. This would happen if the virus became endemic. The current incidence rates are within the normal range, and before the pandemic we also saw peaks with many cases, so we can expect cases to decline again.

But I understand that the more outbreaks there are, the greater the risk of community transmission.

— Yes, obviously, if there are more cases and we can't establish a link, we can't determine whether they're imported or not, and there's a greater chance that the virus will become endemic again. It happened in England: the virus had been circulating for years, and they finally had to declare it endemic. Then cases declined again and they regained the status of elimination. In Spain this year, we haven't had any autochthonous outbreaks; infections are either imported or related to importation.

Where is vaccination coverage?

— As of 2024, 95% of the population has received one dose and between 92% and 93% have received two doses, and the ideal rate to eliminate the disease is above 95%.

He The Garraf outbreak originated within an anti-vaccine family.Is it reckless not to vaccinate your children?

— Everyone has their own opinion. What will allow us to avoid measles in Spain is vaccination, and these people haven't had it so far because the rest of us are vaccinated and we're protecting them. I'm a firm believer in vaccination, but I'm not going to take on the beliefs of others. Humans are the only reservoir of the virus, and we have an effective vaccine. That's why an elimination plan has been implemented, because we can eliminate it in the same way as smallpox.

There are now 13 confirmed cases and around 200 close contacts. How is this affecting professionals?

— Public health professionals are doing a tremendous amount of work to identify contacts, because for each positive case, they must contact all the people they've been in contact with in the last 23 days. And we analyze the samples we receive to make the diagnosis.

What is the importance of having laboratories to analyze samples?

— Vaccination is the most important thing, but so is having laboratories equipped with all the necessary diagnostic techniques. We also characterize and sequence the virus, which allows us to determine whether or not it is circulating in Catalonia or whether the cases are imported.

Are you working on a new elimination plan? Do you think you'll see the disease eliminated?

— Yes, we must maintain the elimination status we have in Spain, and to do so, a series of criteria dictated by the World Health Organization (WHO), which grants this status, must be met. I think it's difficult for me to see the total elimination of the disease because low-income countries don't have access to the vaccine like we do. It's complicated but not impossible.

Experts warn of the global impact that Trump's cuts will have in science and health. One of the consequences will be a resurgence of diseases we've had under control until now. Will we also see an increase in measles cases?

— Yes, probably yes, because it is one of the most contagious diseases in existence, and in an unvaccinated population it has a high chance of spreading.