Dr. Sara Canavati wakes each morning determined to end malaria.
Malaria is bad enough. It kills nearly 600,000 people each year and brings potentially booming economies to a grinding halt. But drug-resistant malaria, with its likelihood of spreading and thereby perhaps multiplying its current death toll, has the tropical medicine world in crisis mode. Then there's Dr. Sara Canavati, in Cambodia, where the resistance was first reported, somehow smiling in the midst of it all.
Canavati is a senior research scientist and infectious diseases epidemiologist. She's been conducting clinical trials and malaria studies in the Greater Mekong subregion for the last 12 years. Canavati has previously worked in northern Myanmar (Kachin State), southern China (Yunnan Province), at the Shoklo Malaria Research Unit along the Thailand-Myanmar border and most recently with the Mahidol-Oxford Tropical Medicine Research Unit (MORU) based in Cambodia. But her work now has her splitting time between Vietnam, Thailand and Cambodia as she conducts studies into what is possibly the most pressing issue in all of global health: artemisinin and multidrug resistance to malaria.
"It was the turning point in my career; he was not meant to die," Canavati began.
"We had given him the latest antimalarial treatment options, but he did not respond to any of them. He had experienced five consecutive episodes of malaria within only seven months. He was a hero. I witnessed how hard he fought this untreatable malaria illness. Sadly, we lost him at his fifth episode from cerebral malaria. I had witnessed an atrocity, a death that could have been averted if we had an effective antimalarial treatment."
Since then Canavati has focused her career on drug efficacy and safety trials. "We are dealing with untreatable malaria," she said.
"Many of my patients have up to seven clinical malaria episodes a year. This chronic form of malaria is unique to this region, but its devastation could spill over many borders if we're unable to effectively address it here."
Resistance to antimalarials is nothing new, according to Canavati. Resistance developed to chloroquine in the late-1950s, sulfadoxine-pyrimethamine and quinine in the mid-1960s, and mefloquine in the late-1980s.
One of the essential components of antimalarial treatment is artemisinin and its derivatives. However, according to recent evidence these drugs are rapidly losing their effectiveness. In 2008, the first signs of artemisinin resistance were reported in Pailin, Cambodia. And since 2014 there have been increasing reports of parasitological and clinical failure following most widely used ACTs (artemisinin-based combination therapies).
ACTs are the current front-line treatment for the most deadly form of malaria. Essentially the drug works like this: the artemisinin derivative quickly kills the majority of parasites over the first few days and then any remaining parasites are wiped out over the next few weeks by the slower-acting partner drug. According to Professor Nicholas Day, Director of MORU, these are the most common ACTs:
For Canavati, these dire recent reports indicate that there is resistance both to the artemisinin compound and the partner drugs.
"The health security and economic consequences of not quickly developing an effective alternative are severe. This is truly a global emergency and demands an emergency response. My patients inspire me each day and I can't help but smile when I'm surrounded by their spirit. I'm determined to end the disease that causes them so much harm."
Follow Dr. Canavati on Twitter: @SaraCanavati
This article was supported with funding from the International Reporting Project
-Photo: Children coming for malaria screening in Sloveo Village in Krachab Health Centre, Pailin Province, Cambodia, 2015