LIMA, Peru (AP) — Peru declared a health emergency in most of its provinces on Monday due to a growing number of dengue cases that are occurring at a time of higher than usual temperatures caused by the El Nino weather pattern.

According to the nation’s health ministry, the number of dengue cases registered during the first seven weeks of this year is twice as high as during the same period in 2023 – with more than 31,000 cases recorded.

“This is a grave problem,” health minister Cesar Vásquez said last week, before the emergency was declared. “And it is getting out of hand.”

The health emergency will enable the nation’s government to transfer funds faster to the affected regions and also transport doctors and nurses. It will cover 20 of the country’s 24 provinces, including regions that surround the capital city of Lima.

A dengue epidemic last year put Peru's public health system under strain as thousands sought care in emergency rooms.

The disease is spread by Aedys Egypti, a mosquito that reproduces in hot and humid conditions.

Although most dengue cases present light symptoms, the disease can cause severe headaches, fevers and muscle pains.

Last year, a dengue epidemic in Peru killed 18 people, while in the first two months of this year 32 Peruvians have died from the virus.

In December, the World Health Organization said that Peru's 2023 dengue epidemic was linked to rains and hot temperatures that helped mosquito populations to grow, especially in the north of the country.