Chikungunya fever cases reported in Italy

October 2007

Italian authorities reported 254 cases of Chikungunya fever, 78 of which were laboratory confirmed, in September.

The outbreak occurred in the province of Ravenna (near Bologna) in Italy’s Emilia-Romagna region. This is believed to be the first outbreak of Chikungunya virus through mosquitoes in Europe.

Active surveillance is continuing. Details of surveillance and outbreak containment were discussed by Italian and European Union health officials during a press conference held Sept. 14 at the European Center for Disease and Control (ECDC) in Solna, Sweden.

“We realize how important the situation is because it is the first in Europe,” said Stefanie Salmaso, MD, director of the National Centre for Disease Surveillance and Health Promotion at the Italian Public Health Institute. “The local response has been robust and vigorous.”

A main concern of health officials is that the disease will be spread by humans who travel and bring the disease to local mosquitoes.

“The significance of what is happening in Ravenna is important to assess to see if the virus can be established and spread to other parts of Europe,” said Denis Coulombier, MD, head of the department of infectious diseases at ECDC.

Italian authorities requested a risk assessment by WHO and ECDC when the outbreak began in early August. ECDC officials credited the swift action of the Italian Ministry of Health with an aggressive surveillance model and public health measures to contain and monitor the Chikungunya outbreak.

“This is a wake-up call, but the impact is limited at this time,” Roberta Andraghetti, MD, medical officer for WHO Europe, said.

Transmitted by mosquitoes

Most cases have been reported in the villages of Castiglione di Ravenna and Castiglione Di Cervia. Tests have confirmed that local tiger mosquitos transmitted the infections in four different areas. All infected patients recovered within a few days and no fatalities have occurred.

CDC officials issued a warning to visitors to the Italian province to avoid mosquito bites and to be aware of Chikungunya fever symptoms.

Symptoms include sudden onset of fever, chills, headache, nausea, vomiting, joint pain with or without swelling, low back pain and rash. Few cases become severe and require hospitalization. Patients with Chikungunya fever should be protected against additional mosquito bites to avoid further virus transmission.

There is no specific drug treatment of Chikungunya fever and care is usually centered on symptoms treatment. Aspirin treatment should be avoided, however, because it can increase the risk of bleeding and could increase risk for Reye’s syndrome.

Chikungunya fever has occurred in the southeastern coast of Africa and in various islands in the Indian Ocean. The virus was first identified in the 1950s in Africa and Asia. Since then, outbreaks have occurred sporadically.