HAVANA (Reuters) -Cuba is fighting a wave of mosquito-borne illnesses including dengue and chikungunya virus that have swept the island in recent ​weeks, affecting nearly one-third of the population and sickening swaths of workers,‌ the country's top epidimiologist said late on Wednesday.

Dengue fever has long plagued Cuba but has grown worse ‌as an economic crisis hampers the government's ability to fumigate, clean roadside trash and patch leaky pipes. Chikungunya, once rare on the island, has also spread quickly in recent months.

"The situation is acute," said Francisco Duran, the country's ⁠chief epidimiologist. He said the ‌government was working "intensely" as during the COVID-19 pandemic to seek medications and vaccines to help tame the virus` impacts.

On Thursday, ‍fumigators probed alleys and crowded buildings in some parts of the capital Havana, among the hardest hit by the mosquito-borne virus, authorities said.

Havana resident Tania Menendez praised those efforts as a necessary ​first step to combating mosquito-borne disease, but warned more needed to be done ‌to clean up the city's garbage-cluttered streets and broken pipes.

"All these problems contribute to the spread of these epidemics," she said.

Chikungunya causes severe headache, rashes and joint pain which can linger months after infection, causing long-term disability.

The World Health Organization in July issued an urgent call for action to prevent a repeat of an epidemic ⁠of the chikungunya virus that swept the globe two ​decades ago, as new outbreaks linked to the Indian ​Ocean region spread to Europe and the Americas.

There is no specific treatment for chikungunya, which is spread primarily by Aedes mosquito species, also a ‍carrier of dengue and ⁠Zika.

Many Cubans, suffering from severe shortages of food, fuel and medicine, cannot purchase insect repellant and face frequent power outages that leave them little choice but ⁠to leave windows and doors open in sultry conditions, facilitating the spread of the disease.

(Reporting by ‌Nelson Acosta, Anett Rios, Mario Fuentes and Alien Fernandez, writing ‌by Dave Sherwood; Editing by Alistair Bell)