Wet, warming weather brings surge in malaria in Kenyan highlands

by AlertNet correspondent | Thomson Reuters Foundation
Wednesday, 3 March 2010 16:12 GMT

By Gitonga Njeru

NAIROBI (AlertNet) Â? Malaria used to be virtually unknown in Kajiado, a Rift Valley village south of Nairobi. But these days 98-year-old Ole Lakutit Kuyioni, one of the village's residents, finds himself in Nairobi's Narok Hospital suffering from his first case of the mosquito-borne sickness - and he's hardly the only one.

"Some of my grandchildren have had to be inpatients in hospitals here" too, the elderly Maasai man said. "Malaria is very rare in Kajiado but nowadays we have experienced an increase of malaria in this region."

Nairobi and parts of eastern Kenya where malaria was never prevalent now are suffering 170 new cases of the disease a week as climate change brings warming temperatures and warmth-loving mosquitoes to Kenya's once-cool highlands, researchers say.

To complicate matters, doctors unaccustomed to seeing the disease are sometimes misdiagnosing patients, treatment drugs are in short supply and adult patients who lack natural resistance are often developing cerebral malaria, one of the most dangerous forms of the disease, scientists and nurses say.


"It is now evident that changes in temperatures in the city of Nairobi have resulted in the increase of malaria parasites and mosquitoes that carry them," said Dr. Andrew Githeko, a lead malaria researcher with the Kenya Medical Research Institute in Nairobi.

Changes in temperature and in rainfall patterns have led to more mosquito habitat and larger numbers of mosquitoes, he said, bringing malaria into parts of the country that never before saw it and expanding the malaria season in other areas.

Worst-hit, he said, have been Nairobi and eastern parts of Kenya, including Meru, Machakos and Embu, where the number of cases has been rising rapidly.

Southern parts of the country near the Tanzanian border have also reported cases of malaria, researchers said.

Studies by the University of Nairobi suggest Kenyan temperatures have averaged as much as 4 degrees Celsius higher than normal over the last three years.

"We call upon the government to do something to reverse the negative impacts of climate change," said Daniel Olago, a University of Nairobi geologist and a partner in the malaria study effort.


The study suggests that malaria in previously unaffected areas may have a much higher fatality rate in part because of drug shortages in many Kenyan health centres.

Dr. Willis Akhwale, head of disease control at the Kenyan Ministry of Health, confirmed that recent outbreaks in Nairobi are particularly worrying because patients tend not to be diagnosed and treated quickly, leading to the development of cerebral complications or kidney failure.

"The second curse for highlanders who get malaria is their inability to access good medical facilities that would diagnose the disease early enough and treat it," he said.

"We as a government need additional funds to combat malaria and climate change," Akhwale said.

He warned of a potential serious spike in deaths from malaria in Nairobi and other highland areas if people do not recognize the symptoms and seek treatment, or of treatment is unavailable.


"Since most people who get infected with malaria never get immediate treatment, the deaths could be in big numbers," he said. Right now, people who travel to hospital with malaria symptoms are often mistakenly treated for typhoid, he said.

He did not give a number for the increase in cases in Nairobi but a nurse at the Kenyatta National Hospital who is not authorized to speak to the press said that last year 65 admissions of malaria-related complications were reported.

This year, by comparison, the hospital is receiving an average of 17 admissions a week, she said. Three quarters of the cases involve patients from areas that were never previously malaria prone, she said. Drug supplies at the hospital remain short, she said.

The nurse said that most of the reported cases involve children under five years old.

Githeko said that most adult cases were of cerebral malaria, a particular problem because adults have not had previous exposure to the disease and have not developed any level of immunity.

Githeko said it was notable that malaria cases were also showing up at periods of the year well beyond the traditional low-land malaria season, which usually runs from May to July.

Nairobi, after years of drought, has had a particularly wet few months and it appears that "variations in rainfall patterns have contributed to a sudden increase" in malaria, Githeko said in an interview.

Gitonga Njeru is a science journalist based in Nairobi.

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