Having circumscribed the outbreak discovered in Anzio, the cases were located in a fairly delimited area. The Region intervened promptly with the disinfestation, which is able to greatly reduce the risk of infection and the intensity of mosquitoes ”. Although it cannot be excluded that in the previous days, some other person was infected. This is explained by Gianni Rezza, epidemiologist of the Istituto Superiore di Sanita '(Iss), who in 2007 had worked on the outbreak that spread in Emilia Romagna affecting more than 250 people. "There have been no indigenous cases of chikungunya in Italy for 10 years, although it cannot be excluded that in this period of time there have not been 2-3 cases a year, perhaps mistaken for flu", he continues. This infection, carried by Aedes albopictus, better known as the tiger mosquito, has in fact symptoms similar to those of the flu. “It is accompanied by fever, joint pains that can last a long time, and in half of the cases by a rash that can itch, Rezza points out. Even in southern France "5-6 cases of chikungunya have already been reported this year", notes the epidemiologist. In our neighbors across the Alps, surveillance on this type of vector and disease is very active, so much so that 2-3 cases are detected every year. “In a temperate country like ours, however, it is easier to control the infection, especially after the disinfestation has been carried out, which contributes greatly to reducing the number of cases.
Insights
Chikungunya is a viral disease characterized by acute fever and transmitted by infected mosquito bites.
The first known epidemic was described in 1952 in Tanzania, although an epidemic in Indonesia had already been described in 1779 possibly attributable to the same viral agent. Since the 2007s, various outbreaks of chikungunya have occurred in Asia and Africa. In Europe in August XNUMX the first indigenous cases were notified in Emilia Romagna.
Symptoms and clinical picture
After an incubation period of 3-12 days, a flu-like symptomatology occurs which includes high fever, chills, headache, nausea, vomiting and above all severe arthralgia (hence the name chikungunya, which in Swahili means "what curve "or" contortes "), such as to greatly limit the movements of the patients who therefore tend to remain absolutely still and assume antalgic positions.
It is also possible to develop a pruriginous maculopapular exanthema. Everything resolves spontaneously, usually within a few days, but joint pains can persist for months. Serious complications are rare and may be of hemorrhagic nature (but not so serious as in the dengue) within 3-5 days, or neurological, especially in children. In very rare cases, chikungunya can be fatal, more so in older people with underlying baseline conditions.
Vectors and responsible agent
The virus responsible for chikungunya belongs to the togaviridae family, of the alphavirus genus. It is transmitted by the mosquitoes of the genus Aedes, as Aedes aegypti (the same one that transmits the yellow fever and the dengue) and is present especially in rural areas, while it is rare or even absent in proximity to the inhabited centers.
Another important carrier is Aedes albopictus, commonly called tiger mosquito, which is also present in the towns of our country. This mosquito is considered to be the carrier that caused the spread of this virus to the Indian islands. Also various species of the culex genus have been identified as potential vectors for this viral agent.
Diagnosis
In the Infectious, Parasitic and Immune-Mediated Diseases (MIPI) Department of the ISS, a WHO Reference Center is active for research on arboviruses and viral haemorrhagic fevers. One of the activities of the center is to diagnose suspected cases of virus diseases transmitted by arthropods and rodents, both imported and indigenous.
The most important import diseases considered are: dengue, chikungunya, yellow fever, West Nile, Japanese encephalitis and those caused by hantavirus. Diagnostic methods are serological and molecular.