Zulkifli Mangkau, Pohuwato, Indonesia – Lukman Ahmad managed in the end to drag himself down from the slopes of Mount Pani toward the southern coast of Indonesia's Pohuwato district. When he staggered back into Botubilotahu village, the 56-year-old was gaunt and reeling.
"I'm fine standing, and I can just about walk," Lukman told Mongabay Indonesia. "But it makes me dizzy."
Alongside his brother, Lukman had planned to spend two weeks on the mountainside sifting through the Botudulanga River and its tributaries for tiny gold nuggets. But when Lukman developed a headache and fever, the brothers feared the worst.
"I've been mining for 25 years," he said, "and this was the first time I've contracted malaria."
Malaria is always contracted from a parasite smuggled into a person's bloodstream by a mosquito bite.
However, when the infection is brought on by either Plasmodium falciparum or P. vivax, two of five parasites that cause the disease, malaria can escalate dangerously by blocking vessels in the brain, risking neurological damage and death.
Official data show that Lukman's case wasn't the only one among the gold miners of Pohuwato, in Gorontalo province on the island of Sulawesi. The head of the malaria section at the provincial health department told Mongabay Indonesia that recorded malaria diagnoses surged from 32 cases in 2022 to 815 last year.
Around four out of five malaria cases were among gold miners, according to Taufik Lantowa, the Gorontalo malaria health lead.
"The rest are farmers, fishermen, and then some are from the general public," he told Mongabay Indonesia.
Emergency descent
On the route down the mountain, Lukman's mind began to play tricks on him, and his focus became increasingly elastic.
"I decided to go home early," Lukman said. "I was afraid something would happen up there."
Malaria deaths fell by more than 40% globally between 2000 and 2015, according to the World Health Organization. Data published by the British Medical Journal showed the global case burden fell from around 262 million diagnoses in 2000 to 214 million in 2015.
Sub-Saharan Africa still accounts for more than 90% of malaria deaths, but the disease remains a stubborn killer in pockets of the Asia-Pacific region.
Construction of Indonesia's new capital city in East Kalimantan province, on the island of Borneo, proceeded alongside a doubling of local malaria incidences in Balikpapan, the nearest city, from 2022 to 2023, data showed. Epidemiologists attribute encroachment into nearby forests for the jump.
Several studies have investigated the extent to which deforestation is associated with vector-borne and zoonotic diseases, with mixed results.
Research published in February this year that matched remote-sensing data to demographic surveys in six sub-Saharan African countries found a link between forest loss and malaria transmission in children, but noted the link depended on family income levels.
"Deforestation is associated with increased malaria prevalence in the poorest households, but there was not significantly increased malaria prevalence in the richest households," the study published in the journal GeoHealth concluded.
Studies that attribute deforestation to increased malaria diagnoses have suggested forest conservation should be included among other prevention efforts, which typically center on distribution of insecticide-treated mosquito nets and indoor residual spraying (IRS).
By contrast, a 2020 study of more than 60,000 children in Africa concluded that there was no statistically significant connection between forest loss and malaria incidences, and that mosquito nets and fumigation should remain priorities.
However, the 2020 research published in the journal World Development noted the potential distinction between small-scale tree cutting in Africa and industrial clearance of forests in Asia.
"We speculate that our findings may differ from those of previous studies because deforestation in Sub-Saharan Africa is largely driven by the steady expansion of smallholder agriculture for domestic use by long-time residents in stable socio-economic settings where malaria is already endemic and previous exposure is high," the authors noted.
"While in much of Latin America and Asia deforestation is driven by rapid clearing for market-driven agricultural exports by new frontier migrants without previous exposure," the study continued.
Gold in them thar hills
From 2001 to 2023, Pohuwato lost 41,800 hectares (104,000 acres) of tree cover, which was equivalent to a 10% decrease in tree cover since 2000, according to Global Forest Watch, a remote-sensing platform operated by the U.S.-based World Resources Institute.
Gorontalo's rich potential attracted bands of gold prospectors in the 19th century, such as the colonial-era Pagoeat Syndicate. Local communities living in Pohuwato soon joined the rush using homespun ways to extract tiny fragments of gold from the riverbed, techniques still employed today.
Many artisanal mining operations around the world rely on dangerous use of mercury or cyanide to separate gold from its ore.
However, the alluvial extraction practiced by Lukman here in Pohuwato uses the age-old tradition of panning, in which a wide-brimmed sieve is lodged in the river to collect the smallest nuggets of precious metal hiding in the riverbed.
Lukman and other traditional miners make a frame up to 2 meters (7 feet) long from timber and bamboo, before adding a weave of coconut fiber to the barrier to catch sedimentation carried downriver.
By the 1950s, the Pohuwato gold rush was in full swing, and by the 1970s Mount Pani had become a focal point for foreign companies like BHP-Utah, Cyprus Amax, Newcrest, Placer Dome and Tropic Endeavour, as well Aneka Tambang, an Indonesian state-owned mining firm.
Ismail Tino remembers intact forest around the gold sites in Mount Pani, Mount Ilota and Mount Baginite, but as mining in Pohuwato expanded to rivers like the Botudulanga, so too did encroachment and tree cutting.
The arrival of companies at these Pohuwato locations further contributed to the deforestation, he said.
In his first two decades panning for gold in the valleys of Pohuwato, Ismail contracted only the occasional common illnesses.
"Even though I slept on the edge of the river in a mine pit with puddles, I never got malaria," he told Mongabay Indonesia.
However, Ismail has admitted himself to hospital twice and to a clinic three times in the last few years. On each occasion he received a diagnosis of malaria.
"As far as the eye can see, that once-dense forest is now clear," he said. "The difference is very visible: I suspect this is the cause of the emergence of many malaria mosquitoes."
November rains
As the intensity of the rainy season changed last November, Lukman looked on from the forest. The gold collectors watched the river rise, and slept for the most of the day.
It was then that Lukman began to overheat, before he felt chills as he lay prostrate under a thin shelter. The headache felt like daggers.
"This was the most severe pain I ever felt," he said. "Never like this before."
Lukman started as a child following his father to look for gold in his homeland in North Bolaang Mongondow district, which is home to the Mongondow Indigenous people, around 150 kilometers (90 miles) east of Pohuwato. In 1986, his parents settled in Pohuwato, where Lukman got married and started a family. He'd been sick before plenty of times, but never like this.
"I was surprised just how different the headaches were," he said.
Budi Haryanto, a professor at the University of Indonesia medical school, said malaria often thrives at mining sites; the puddles left over from mining activity are ideal breeding spots for mosquitoes. The increase in cases requires an urgent response from policymakers, Budi said.
"Don't just wait to treat it," Budi said. "If that's the model for handling malaria, it will never end and will continue to recur."
Doctors told Lukman in September last year he would be unable to work for at least a month, but he was soon hiking back up Mount Pani.
"I live from mining," he said. "If I don't mine, what will my wife and children eat?"
Banner image: Gold mining erodes land cover in Pahuwato. Image by Zulkifli Mangkau/Mongabay Indonesia.
[This story was reported by Mongabay's Indonesia team and first published here on our Indonesian site on Aug. 9, 2024.]
Citations
Gulland, A. (2015). Annual malaria deaths have halved since 2000. BMJ, h4998. doi:10.1136/bmj.h4998
Estifanos, T. K., Fisher, B., Galford, G. L., & Ricketts, T. H. (2024). Impacts of deforestation on childhood malaria depend on wealth and vector biology. GeoHealth, 8(3). doi:10.1029/2022gh000764
Bauhoff, S., & Busch, J. (2020). Does deforestation increase malaria prevalence? Evidence from satellite data and health surveys. World Development, 127, 104734. doi:10.1016/j.worlddev.2019.104734