In a northern Italian village, a tropical epidemic
By Elisabeth Rosenthal Published: December 21, 2007
CASTIGLIONE DI CERVIA, Italy: Panic was spreading this August through this tidy village of 2,000 as one person after another fell ill with weeks of high fever, exhaustion and excruciating bone pain, just as most of Italy was enjoying Ferragosto, its most important summer holiday.
"At one point, I simply couldn't stand up to get out of the car - I fell," said Antonio Ciano, 62, an elegant retiree in a pashmina scarf and trendy blue glasses. "I thought 'OK, my time is up. I'm going to die.' It was really that dramatic."
By mid-month, more than 100 people had come down with the same malady. Although the worst symptoms dissipated after a couple of weeks, no doctor could figure out what was wrong.
"In the bar, people were really hysterical," said Rino Ricchi, a road worker who fell ill.
They blamed pollution in the river. They attacked the government. But most of all they blamed recent immigrants for bringing such pestilence to their sleepy settlement of pastel stucco homes.
"Why immigrants? I kept thinking of these terrible diseases that you see on TV, like malaria," said Rina Ventura, who owns a shop selling shoes and purses. "We were terrified - there was no name and no treatment."
Oddly, the villagers were both right and wrong. After a month of investigation, Italian public health officials discovered that the people of Castiglione Di Cervia were, in fact, suffering from a tropical disease - Chinkungunya, a relative of dengue fever, normally found in the Indian Ocean. But the "immigrants" who were spreading disease were not humans but insects: tiger mosquitos, who can thrive in a warming Europe.
Aided by global warming and globalization, Castiglione Di Cervia has the dubious distinction of playing host to the first outbreak in modern Europe of a disease that had previously been seen only in the tropics.
"By the time we got back the name and surname of the virus, our outbreak was over," said Dr. Rafaella Angelini, director of the public health department in the regional capital of Ravenna. "When they told us it was Chinkungunya, it was not a problem for Ravenna any more. But I thought: this is a big problem for Europe."
The epidemic proved that tropical viruses are now able to spread in new areas, far north of their previous range. The tiger mosquito, which first arrived in Ravenna three years ago, is thriving across southern Europe and even in France and Switzerland.
And if Chinkungunya can spread to Castiglione - "a place not special in any way," Angelini said - there is no reason why it cannot go to other Italian villages. There is no reason why dengue, an even more debilitating tropical disease, cannot as well.
"This is the first case of an epidemic of a tropical disease in a developed, European country," said Roberto Bertollini, director of the World Health Organization's Program on Health and the Environment. "Climate change creates conditions that make it easier for this mosquito to survive and it opens the door to diseases that didn't exist here previously. This is a real issue. Now, today. It is not something a crazy environmentalist is warning about."
Was he shocked to discover Chinkungunya in Italy, his native land? "We knew this would happen sooner or later," he said. "We just didn't know where or when."
It certainly caught this little town off guard on Aug. 9, when public health officials in Ravenna received an angry call from Stefano Merlo, who owns the gas station.
"Within 100 meters of my home, there were more than 30 people with fevers over 40 degrees - I wanted to know what was going on, I knew it couldn't be normal," said Merlo, 47.
August is not the season for high fevers, Angelini agreed, and within days of interviewing patients she was intrigued.
"The stories were so similar and so dramatic," she said. "But we had no clue it was something tropical."
Hardworking shopkeepers like Venturi could not leave bed because their hips hurt so much. Able-bodied men could not lift spoons to their mouths. (Months later, many still experience debilitating joint pain.)
From the start, doctors suspected the disease was spread by insects, rather than human-to-human contact. While almost all homes had one person who was ill, family members seemed not to catch the disease from each other.
They initially focused on sandflies, since the disease clustered on streets by the river.
Canceling their traditional mid-August vacations (in Italy, a true sign of panic), health officials sent off blood samples, called national infectious disease experts, searched the Internet and set out traps to see what insects were in the neighborhood. The first surprise was that the insect traps contained not sandflies but tiger mosquitos, huge numbers of them.
The scientific survey confirmed what residents of Castiglione had come to accept as a horrible nuisance, though not a deadly threat.
"In the last three or four years, you couldn't live on these streets because the mosquitos were so bad," said Ricchi, standing at the entrance to his neatly tended garden, where mosquito traps have now replaced decorative fountains.
"We used to delight in having a garden or a porch to eat dinner. You couldn't this year, you'd get eaten alive,"
Said Angelini : "They were treating the mosquitos like an annoyance. They knew that mosquitos could spread tropical diseases but they had peace of mind because they knew this didn't happen in Italy."
Ravenna immediately set about killing the bugs in the hopes of containing the epidemic. Workers sprayed insecticides and went into each family's garden, emptying flower pots, fountains and the rainwater collection barrels to remove the mosquitos' breeding ground.
By early September, there were no new cases in Castiglione Di Cervia. But there were a number of mini-epidemics in cities in the region - Ravenna, Cesena, Rimini - set off by tiger mosquitos there. Each was controlled in the same way.
By that point, the doctors had catalogued the patients' symptoms and tried to match them to mosquito-borne diseases.
"We realized," Angelini said, "we were seeing a photocopy of an outbreak on Réunion," a French island in the Indian Ocean where more than 10,000 people have had Chinkungunya in the last two years. Blood tests confirmed the diagnosis. By summer's end nearly 300 Italians had been diagnosed with home-grown Chinkungunya.
Chinkungunya is spread when tiger mosquitos drink blood from an infected person and - if conditions are right - pass the virus on when they bite again. Tiger mosquitos first came to southern Italy with shipments of tires imported from Albania about a decade ago but have expanded their habitat steadily north as temperatures have risen. They now exist in Corsica and southern France as well.
But the doctors were baffled by how Chinkungunya made its way into mosquitos in northern Italy since no one in Castiglione Di Cervia had been abroad. In the past two years France (especially Paris) has had a number of "imported" Chinkungunya cases, in travelers returning from Réunion. But the disease has never spread in France, because the mosquito could not thrive there.
Eventually investigators discovered a link: One of the first men to fall ill in Castiglione Di Cervia had been visited by a feverish relative in early July. That relative, an Italian, had previously traveled to Kerala, India. Chinkungunya traveled to Italy in his blood, but climatic conditions are now such that it can spread and find a home here.
Now it is winter in Castiglione Di Cervia, near freezing as the sun went down on a recent evening and Christmas lights glowed across the piazza. There are no mosquitos now.
But dozens of residents still suffer from arthritis, a known complication of Chinkungunya.
Ricchi, the roadworker, says he still has trouble clenching his fists and his left ankle has horrible pains. Three people in the town died after getting the virus, Merlo said, although all had other illnesses as well.
From the start, townspeople noticed that the very elderly never got the disease. Now it makes sense: "If all you do is walk the 50 yards from your home to the church, there's not much chance to get bitten," Ciano said.
But the biggest mystery is whether Chinkungunya will emerge here next summer. In the tropics, it is a year-round disease, since the mosquitos breed continuously. But the virus can winter over in mosquito eggs, too, and no one knows if there are reservoirs of sleeping eggs in some pool of water in Italy.
With climate change upon us, Bertollini said, Chinkungunya surely be back somewhere in Europe again.
