The United States has registered five mosquito-borne infections with the malaria pathogen within the country for the first time in 20 years. In the past two months, four cases have been identified in the immediate geographical vicinity in the southeastern state of Florida, the US health authority CDC reported on Monday (local time). An infection was also detected in Texas.

It has not happened since 2003 that the malaria pathogen is transmitted within the USA by native Anopheles mosquitoes. This distinguishes the cases of patients who become infected in malaria risk areas and then return to their country.

All patients are being treated and are already on the mend, the CDC said. Mosquito surveillance and control measures have been taken in the affected areas. Despite the recently registered infections, the risk of malaria infection in the USA remains “extremely low”. In areas where the Anopheles mosquito can survive all year round due to the climatic conditions, the risk is higher – especially if travelers from malaria risk areas are staying there.

Fever, chills, nausea

Malaria is caused by so-called Plasmodium, which transmits infected mosquitoes to humans. Infected people often develop fever and chills and suffer from nausea, muscle and joint pain and fatigue. In severe cases, there are also shortness of breath, cramps and bleeding. Most severely affected people die without medical treatment.

The WHO estimates that around 619,000 people will die from malaria worldwide in 2021, slightly fewer than the approximately 625,000 the year before. Cases of the disease rose to 247 million, but the rate of increase has slowed, the annual malaria report said in late 2022. Around 95 percent of the illnesses and deaths were registered in Africa. About 80 percent of the deaths there were children under the age of five. The WHO Region Europe has been free of malaria since 2015. However, scientists expect infectious diseases such as malaria and dengue fever to spread north due to climate change.