Two recent studies have revealed that the presence of drug-resistant strains of malaria on the rise in Southeast Asia. Research has raised the alarm among scientists leading the fight against one of the world's most persistent health problems.
The disease is "almost untreatable," said Arjen Dondorp, principal author of one of the studies and director of malaria research at the Mahidol-Oxford Tropical Medicine Research Unit in Thailand.
The strains are currently present in parts of Southeast Asia, where the disease has declined sharply over the last decade. However, according to experts, they could have devastating consequences if they were to reach areas more severely affected by malaria, such as sub-Saharan Africa.
Here are five key findings from the reports.
What exactly did the studies find?
Two studies published in the Lancet Journal of Infectious Diseases last week showed that resistance to the most common form of malaria medication has spread and worsened since 2013. Healthcare professionals use a combination of dihydroartemisinin and piperaquine or DHA-PPQ to treat malaria cases. The drug is given in pill form and can be taken orally.
In the regions studied, this treatment did not cure the disease with an overall rate of 50 percent – or 13 percent in northeastern Thailand – according to new findings. 38 percent in western Cambodia, 73 percent in northeastern Cambodia and 47 percent in southwestern Vietnam.
Does that mean that there are forms of malaria that can not be cured?
Not exactly. There are several drug combinations that could still treat the resistant strains. However, the treatments themselves can lead to more resistance.
"In general, the use of treatments to kill microorganisms provides a selective advantage for the development and spread of resistance," said Will Hamilton, a medical student at the University of Cambridge and author of a study of the studies. "This is evolution through natural selection in action." He compared the emerging phenomenon that bacteria develop resistance with antibiotics.
And there are only a limited number of alternative therapies.
"The problem with malaria is that the treatment options are very limited," said Dondorp. "If you can not treat the infections well, the malaria will increase again, and as the number increases, the number of deaths will increase.
Why is this happening in Southeast Asia?
Southeast Asia has historically been a breeding ground for the development of resistant strains of malaria, and scientists are not quite sure why, but they suspect that this is partly due to the fact that there are frequent and Hamilton said strong drug use will put pressure on strains to adapt and find ways to develop resistance.
Another reason, according to Dondorp, may be how malaria medicines are taken in the region Patients with malaria may take weaker medications or stop taking pills as soon as they Feel better instead of stopping the treatment, making the parasite more resistant to the medication.
Finally, Southeast Asian countries have a relatively low transmission rate, which means resistant strains meaning less competition from more dominant non-resistant strains.
What would happen if this resistance spread?
It would be bad. A major concern is that the tribes are spreading in Sub-Saharan Africa, where malaria is the most common and logistically most difficult to treat.
There are precedents for this. In the 1960s, a strain of malaria found in Southeast Asia became resistant to the then-common drug chloroquine and eventually spread to sub-Saharan Africa. The lack of alternative medicines caused the number of malaria deaths to double in the 1980s.
Scientists fear that the story could be repeated.
"The spread of these resistant parasites to other regions, such as Africa, is very likely and real concern," said Didier Ménard, head of the malaria genetics and resistance group at the Institut Pasteur Paris and one of the reviewers of the study.
What can be done in the meantime?
Finally, scientists say that the only way to completely eradicate these resistant strains is to eradicate the disease itself in the region.
Such efforts have been undertaken worldwide since 1955, when the World Health Organization introduced the malaria eradication problem. Since then, dozens of countries have been declared malaria free, but only two of them, the Maldives and Sri Lanka, are located in Southeast Asia.
Dondorp said, "otherwise we'll never be able to eradicate malaria." It will come back and spread in other countries. "