Every summer has its “monster under the bed”. Once are the jellyfish, then the ticks, today are the mosquitoes. No longer just annoying outdoor evenings, but potential virus vectors with names that play exotic and threatening: Dengue, Zika, West Nile. The debate lights up, social networks are filled with alarms and “grandmother’s remedies”, while the feeling is always the same: that something is changing, and not for the better. But the question is: how much is real and how much of perception? Do we really have to fear every puncture or do we risk falling into a collective psychosis?

The latest data

For weeks, infectiousological centers have recorded a surge in requests on Dengue, Zika and West Nile. And not only from those who leave for tropical destinations: fear also grows between those who stay in Europe. In 2024, Italy recorded over 500 cases of Dengue, of which more than 200 natives. A number that until a few years ago seemed unthinkable.

To better understand what is going on, Today spoke with Francesca Scolari, entomologist and researcher of the Molecular Genetics Institute of the National Research Council (IGM-CNR) of Pavia.

From the national surveillance system, updated at the end of July 2025, it shows that in Italy 98 cases of Dengue (of which 3 natives, no deaths), 4 cases of zika (all imported, no deaths) and 89 cases of West Nile (with 13 deaths) were recorded. For the West Nile, the circulation of the virus is in line with that of 2024, according to the Ministry of Health. The situation is under control, but it is essential to keep supervision high and promote prevention, even on an individual level.

How they are transmitted

“Dengue, Zika and West Nile are viruses transmitted to man through the sting of infected mosquitoes, not by air as an influence or Covid-19. For this reason they are called arbovirus, that is, viruses transmitted by arthropods”, explains Scolari. In Italy, these infections can be imported (from travel abroad) or native, that is, transmitted to the national territory. Mosquito females acquire viruses when feeding on blood, necessary for the development of eggs. After pointing an infected guest, the virus multiplies in their body and can be transmitted to another person with a new puncture.

Symptoms and how to recognize the virus

The symptoms of these viruses are similar and can be confused with the flu. In our country there are mosquitoes potential carriers: the tiger (Aedes albopictus), active during the day, and the Municipality (Culex Pipiens), active in the evening and at night. The people most at risk of serious forms are elderly and patients with chronic pathologies. The incubation lasts on average a week, but it can be longer in immunosuppressed subjects. After traveling in risk areas, it is important to monitor the symptoms and contact the doctor immediately to encourage early diagnosis.

• Dengue: high fever, headache, muscle and joint pain, skin rash; It can rarely evolve in severe hemorrhagic form. The virus is transmitted by mosquitoes of the Aedes genre (including the tiger mosquito, now widespread in Italy).
• Zika: slight symptoms (fever, conjunctivitis, exanthema) or absent, but in pregnancy it can cause serious fetal malformations. In Italy, only imported cases have been recorded in Italy, but the tiger mosquito could allow local transmission.
• West Nile: transmitted by mosquitoes of the Culex genus (common), in about 80% of cases are asymptomatic. However, it can cause fever, headache, nausea, muscle pain, and in rare brain or meningitis cases. Human beings and horses are accidental guests: they do not contribute to the spread of the virus.

Prevention: the most effective weapon

There are no specific vaccines or antiviral for these diseases: the treatment is symptomatic (antipyretic, hydration). Prevention remains the best strategy: to use repellents, mosquito nets and protective clothes; Eliminate stagnation of water, empty sauces and containers; protect yourself both during the day and in the evening, since the vector species have different habits; Use larvicides based on Bacillus Thuringiensis Israelensis; Identify and remove foci and conduct targeted disinfestation campaigns.

“Global warming and environmental alterations are changing the ecology of the Mosquito Vectors – concludes Scolari -. Higher temperatures and mild seasons favor the survival of insects and expand the areas in which they can live. Intense rains followed by heat waves create ideal conditions for the deposition of eggs and the development of the larvae”.

These diseases are no longer just “tropics problems”: they have also become ours. The challenge will be to live with us, learning to reduce risks with aware behavior and active prevention. Zero risk does not exist, but alarmism either helps. The real challenge will be to find a balance: to remain aware and informed.