A four-year-old Italian girl has died of cerebral malaria in northern Italy, a region free of the disease, in what doctors see as a very mysterious case. Sofia Zago died in Brescia on Sunday night, after being rushed to hospital with a high fever on Saturday.
Italy is free of the Anopheles mosquito that carries cerebral malaria, the deadliest form of the blood disease. But after a scorching August, some fear that it might have reached Italy.
A flight could have brought it in.
Sofia had been on holiday with her parents at Bibione, an Adriatic resort near Venice.
Trento, where the girl's malaria was diagnosed on Saturday, lies within the Trentino region in the foothills of the Alps.
"It's the first time in my 30-year career that I've seen a case of malaria originating in Trentino," said Dr Claudio Paternoster, an infectious diseases specialist at Trento's Santa Chiara Hospital.
Since the 1950s, Italy has not had a malaria problem because mosquito-infested marshes were drained.
There is speculation that Sofia might have caught malaria from one of two children treated for it at the Trento hospital after 15 August. They had caught it in Africa, and recovered.
Sofia had had treatment there for child diabetes and there was a break before her emergency readmission to the hospital at the weekend.
A Trentino health official, Paolo Bordon, said Sofia had not been in the same ward as the other two children. Sofia had not had a blood transfusion, he added, stressing that the treatments for malaria and diabetes were utterly different.
The Plasmodium Falciparum parasite carried by the Anopheles mosquito can kill a human within 24 hours.
About 438,000 people died of malaria in 2015 in the 95 tropical countries where it is endemic, Italy's Corriere della Sera daily reports.
Only some types of mosquito are able to transmit the disease from person to person.
Risky insects are found in large areas of Central and South America, Africa, Asia, the South Pacific and some parts of Eastern Europe, but not in the rest of Europe.
As a result, malaria is largely limited to tropical areas - cases appearing within the European Union are typically "suitcase" ones, linked to recent travel to other parts of the world where malaria is present.
The latest case in northern Italy has baffled experts. It is not clear how the girl caught it, but her case is not unique.
The European Centre for Disease Prevention Control closely monitors cases and has found a few cases of "locally acquired" malaria in the EU - two in France and three in Spain in 2014.
But there were explanations for how some of these might have occurred. One was a patient who had received a kidney from a donor with malaria; another was a newborn whose mother had recently returned from Equatorial Guinea.
One of the Spanish patients had no history of travel, but lived a few kilometres from a town where a "suitcase" malaria person lived. No infected local mosquitoes were found, but lab tests showed two people had an identical strain of the disease.