Multidrug-resistant forms of malaria-causing parasites are spreading across South-East Asia, leading to “alarmingly high” treatment failure rates of widely-used frontline medication, researchers warned on July 23, 2019.
In twin studies published in The Lancet Infectious Diseases journal, they revealed that in parts of Thailand, Vietnam and Cambodia, up to 80% of the most common malaria parasites were now resistant to the two most common antimalarial drugs.
The Plasmodium falciparum parasites have also acquired resistance to one of the newest and most potent frontline drug combinations, which was linked to the failure of treatment in half of cases, they said.
“These worrying findings indicate that the problem of multidrug resistance in P. falciparum has substantially worsened in South-East Asia since 2015,” says Olivo Miotto from the Wellcome Sanger Institute and University of Oxford in the United Kingdom, who co-led the study.
“This highly successful resistant parasite strain is capable of invading new territories and acquiring new genetic properties.”
He warns of the “terrifying prospect” of the parasite spreading to Africa, where most malaria cases occur.
A similar resistance to a long-time frontline malaria drug, chloroquine, contributed to millions of deaths across Africa in the 1980s.
More than 200 million people are infected with the P. falciparum parasite, which is responsible for nine out of 10 malaria deaths globally.
A drug combination known as DHA-PPQ was initially effective against the parasite, before doctors noticed signs of resistance in 2013.
The most recent study into DHA-PPQ failure rates showed they have now reached 53% in southwest Vietnam and as high as 87% in northeastern Thailand. – AFP