Filenews 2 April 2025 - by Marilena Panayi
With the changing weather in Europe and spring favouring the hatching of all kinds of insects, including mosquitoes, the European Centre for Infection Control (ECDC) is vigilant.
In recent months, the Chikungunya virus has been under the microscope of scientists, which is constantly included in the weekly reports on the spread of infectious diseases of the ECDC.
In fact, according to the ECDC, from the beginning of 2025 until the last week of March, more than 80,000 cases of Chikungunya disease and 46 deaths attributed to the virus had been recorded internationally.
Literally, the word "Chikungunya", in the African language Kimakonde, means "one who walks bent", and this designation was given because of the severe arthralgia caused by this particular disease.
Along with the virus, the mosquito that transmits it is also under surveillance, with Cyprus being among the -admittedly few- countries in which it has been detected or more correctly reappeared.
Chikungunya virus disease, according to the latest ECDC report, "is a disease, widespread in tropical and subtropical regions".
Globally, "the virus is mainly transmitted by the Ae. aegypti and Ae. albopictus mosquitoes".
Aedes albopictus "is found in a large part of Europe", but Aedes aegypti "is mainly found in Cyprus, around the Black Sea and in the outermost region of Madeira".
This particular mosquito, it is worth mentioning, had been eradicated for decades from Cyprus as well. However, in 2022 it was re-identified, in small populations, with the Health Services taking action to combat it since then. It is estimated that it reappeared, or more correctly reintroduced into Cyprus by one of the modern means of transport (by plane or ship).
The mosquito can transmit the Zika and Chikungunya viruses, however, for mosquitoes to transmit these viruses, they must first be present in an area. This fact, after all, is the main reason why the competent authorities have been particularly reassuring in recent years, despite the fact that organized monitoring of Chikungunya disease in Cyprus is not done and at the same time, the symptoms it causes often refer to other known diseases.
The Aedes Aegypti mosquito prefers to live near or inside homes and hatches in water collection containers, open tanks, fountains, cans and other cans that run out of water and are filled with rainwater, flower pots, etc.
Symptoms can last for years
Chikungunya disease is caused by the virus of the same name, which is transmitted through mosquitoes of the genus Aedes (mainly of the species Aedes aegypti, but also of the species Aedes albopictus).
According to the National Public Health Organization of Greece, "mosquitoes are infected by infected people. Vertical transmission of the virus (from mother to child) has also been reported, from mothers who got sick in the last week of pregnancy."
"Indigenous transmission has occurred in Europe and the U.S., following the introduction of the virus in infected travellers who returned from endemic countries."
Often the symptoms of the disease are mild and "the infection can be asymptomatic (while those infected – even asymptomatic – can transmit the viruses to mosquitoes)".
The most common clinical picture of the disease includes sudden onset of fever, arthralgias/polyarthralgias/arthritis (joint swelling) and rash, while other common signs and symptoms include chills, muscle aches, headache, nausea, vomiting, photophobia, fatigue, conjunctivitis.
The acute phase lasts about 10 days. "The typical clinical sign of the disease is arthralgia."
"The chronic phase of the disease is characterized by recurrent arthralgia, occurs in varying rates (mainly in 30-40% of those infected), and can last for years in some cases. In the elderly, arthralgia can develop into chronic rheumatoid arthritis syndrome."
Mosquitoes, travellers and the spread of the virus
Cases have been reported in 14 countries/regions, with the American continent recording, so far, the highest numbers.
In continental Europe, no cases have been recorded in 2025, but an epidemic is recorded in the outermost territories of France (Mayotte).
From the beginning of 2025 until March 26, the countries reporting the highest number of CHIKVD cases are Brazil (71,578), Argentina (1,550), Bolivia (77) and Peru (32). 393 cases were also reported in Asia (Pakistan) and two cases in Senegal.
The two species of mosquitoes (Aedes Aegypti and Aedes albopictus) that can carry the chikungunya virus, are also carriers of the dengue virus and the Zika virus. Aedes aegypti, found in Cyprus, is also responsible for yellow fever.
According to the ECDC, "the possibility of further transmission of dengue virus and chikungunya virus to the mainland EU/EEA is linked to the introduction of the virus by travellers".
Dengue
The infection is not serious in most cases, but there is evidence that during pregnancy, it may be associated with genetic abnormalities of the foetus (microcephaly).
Zika
The Zika virus is similar to the virus that causes dengue fever, and is transmitted, like dengue, by bite of an infected mosquito. Symptoms of the disease include fever, headache, rash, conjunctivitis, muscle aches, and arthralgias. The disease is usually mild and lasts 4-7 days.
The World Health Organization (WHO) estimates that there is a possibility of major outbreaks of the Zika virus worldwide. In February 2016, the WHO declared Zika a "Public Health Urgent Problem of International Concern."
Yellow fever
Yellow fever is caused by the mosquitoes Aedes and Haemogogus. It can cause headache, fever, myalgia and nausea. It is difficult to diagnose and is often confused with other diseases, such as malaria and viral hepatitis. There is an effective vaccine and supportive treatments, but the disease remains a significant threat in tropical regions of Africa and South America.
Climate change has changed mosquito behaviour
The appearance and reappearance of diseases, which presuppose the existence of mosquitoes, is attributed by scientists, to a large extent, to climate change and the modern way of life.
The increase in temperature and in general the warmer conditions that prevail throughout the planet, favour the year-round presence of mosquitoes, which by extension favours the constant risk of virus transmission.
In addition, the modern lifestyle, especially in urban areas, favours the hatching of mosquitoes. In particular, mosquitoes need water to complete their biological cycle. In urban centers, rainfall (little or none) creates the right conditions through abandoned water containers, used tires and other waste that can retain rainwater.
Mosquitoes, as scientists find, have already managed to adapt to the new conditions, survive and at the same time, are transported from one corner of the planet to another through modern means of transport.
