Kenya is among countries that might be required to replace the commonly used rapid diagnostic kits for malaria.
This follows a serious threat of mutation of the malaria parasite, giving it the ability to remain undetectable by the commonly used kits.
World Health Organization said this mutation has been widely reported in western Kenya.
"This puts patients at risk of misdiagnosis, significant morbidity and potentially death,” WHO said.
Kenya adopted the use of rapid diagnostic tests (RDTs) to test all malaria cases on October 4, 2012, enabling better targeting of treatment and improved surveillance.
Previously, patients were diagnosed through observation of clinical symptoms.
The majority of the kits used in Kenya diagnose infection by the parasite, Plasmodium falciparum, by targeting one of its antigens, the histidine-rich protein 2 (HRP2).
However, some parasites are nowadays not expressing the HRP2 protein due to mutations in the genes that encode it.
Consequently, HPR2-based RDTs are unable to detect infections with such parasites.
“This lead to a reversion to microscopy as the primary diagnostic tool in this region,” WHO said.
Over the past six years, an increasing number of African and Asian countries where diagnosis is heavily reliant on HRP2-based RDTs have reported gene mutations, raising the threat to a new level.
WHO said the Horn of Africa is disproportionately affected, with high prevalence of such mutations reported in areas of Ethiopia, Eritrea, Djibouti, Sudan, South Sudan and Kenya.
In Kenya, a few cases were reported in Mandera county, Narok West, and more around Lake Victoria.
Recent surveys in the Horn of Africa region found that more than 50 per cent malaria cases are missed by the current test kits.
“Failure to detect and treat infection can result in increased disease, including severe disease and death,” WHO said.
Experts recommend that if a country records five or more false negatives in malaria tests, they should immediately change their testing strategy.
There are some alternative non-HRP2 based rapid tests options available, having been approved through the Global Fund Expert Review Panel for Diagnostics, WHO said.
In 2015, the prevalence of microscopically confirmed malaria among children less than 15 years in Kenya was eight per cent nationally and 27 per cent in the lake-endemic region of western Kenya.
The Ministry of Health says there are an estimated 3.5 million new clinical cases and 10,700 deaths each year, and those living in western Kenya have an especially high risk of malaria.
Kenya is also introducing malaria vaccine for children in eight counties in western Kenya.
Edited by A.N
