Johan Tahun pauses to search the canopy as he follows a plastic water pipe up the Tonduk River to the water source for the Batek. Although all the surrounding forest has been logged, this narrow corridor was left untouched by loggers. The problem is that a manganese mine opened in 2016 at the top of this watershed. The Batek believe that when it rains heavily, which is common in this rainforest, toxic waste from the mine wash into this ravine and contaminate their water — and they believe that mine contamination triggered the mysterious illness that claimed 16 lives in their tight community. (James Whitlow Delano/James Whitlow Delano)

Li climbs up bare rock to the manganese mine that opened in 2016. Four years ago, this was a rainforest. The Batek’s water source sits below the mine, and they believe toxic runoff from the mine is contaminating it. (James Whitlow Delano/James Whitlow Delano)

For decades, the Batek of Kuala Koh had seen their territory and lifestyles encroached upon. Then, in May, the high fevers set in. “Their throats swelled and then they couldn’t swallow or eat,” recalled headman Mahmet Pokok. In rapid succession, one after another, they began to fall ill.

“Soon people couldn’t breathe,” Pokok continued. “They shriveled and their bodies turned black.” Then some began to die.

The mysterious illness spread quickly, claiming 16 lives within two weeks in a community of 186 members of this clan of Malaysia’s last hunter-gatherers. In the end, 100 Batek would be hospitalized, and only 20 were left unaffected.

A Sept. 25 report from Malaysia’s Ministry of Health declared the cause of deaths to be measles. “Of the 16 deaths,” wrote Health Minister Dzulkefly Ahmad, “four (4) deaths were confirmed by measles, eight (8) were epidemiologically related to measles outbreaks, while another four (4) deaths could not be determined due to severe decay. Based on the results of environmental sample analysis and forensic reports, deaths were not due to heavy metal poisoning.”

The Batek, however, are unconvinced by the government report.

“The sickness was new,” Mahmet Om recounted. “We know about the measles. Our shaman know how to cure them.”

One of the survivors recounted what it was like.

“My throat swelled. My eyes turned red and everything looked blurry. . . . My whole body ached,” recalled Nira, who lost two sisters to the illness. “I was in the hospital [in Gua Musang, the closest large town] for over two months.”

Some of the clan believe a nearby manganese mine is to blame.

“The water tasted bitter . . . was oily,” Nira said. Som, sitting nearby, said she vomited after drinking the water.

“It smelled of oil [petroleum] and wood. The water had an oily sheen,” Pokok added.

The Batek, an Australo-Papuan people, are a remnant of the very first wave of human migrants to leave Africa, arriving tens of thousands of years ago — a distinct, indigenous ethnicity from the majority Malay. They live as hunter-gatherers, beneficiaries of Malaysia’s rainforests.

But over the course of nearly four decades, logging and subsequent massive oil palm plantation expansion have slowly eaten up their entire, unprotected rainforest. With the completion of Malaysia Federal Route 8 in 1983, Federal Land Development Authority, a government agency tasked with rural development, accelerated logging for land clearance. Once the land was opened up, vast monoculture oil palm plantations were planted.

Soon, the Batek found themselves in constant retreat. By the time of my first reporting trip in 2010, the Batek of Kuala Koh were confined to a thin strip of buffer forest at the boundary of Taman Negara National Park. That last parcel of buffer forest was being surveyed for impending logging operations. The Batek received assurances that the logging would be done selectively. By 2015, the entire buffer forest was gone, and the land planted with oil palm by a private company, without proper consultation with the Batek.

The Batek, a hunter-gatherer people known to range for weeks in trackless rainforest, were deeded with a tuft of eight acres of “communal” forest; Kuala Koh, which sat adjacent to a massive forest, was now completely encircled by oil palm plantations.

Just when it seemed things could not get any worse, in 2016, a manganese mine broke ground directly above the main water source for Kuala Koh, the Tonduk River.

“I believe we were poisoned because of the mine,” Mahmet Om said. “When it rains, we don’t use water from Tonduk.” Runoff from the mine drains directly into the Tonduk watershed.

Manganese is used as filler in dry cell batteries for smartphones, tablets and computers, in the manufacture of stainless steel and to make aluminum drink cans thinner and stronger. Overexposure to manganese is toxic, and symptoms can mimic Parkinson’s disease. Hallucinations, nerve damage, weak muscles, headaches and bronchitis are also possible.

Federation of Private Medical Practitioners’ Associations Malaysia president Steven Chow told the Observer in September, “Based on our research and the pattern of deaths, there was an outside environmental factor of either poisoning by another chemical, another pollutant or an extremely high level of manganese from the mine that was at least partially responsible for the spate of deaths.”

Private testing by FPMPAM of the Tonduk River water found “unhealthy levels of manganese, metals and fecal matter.” The fecal matter from wild elephants littered the muddy trial as we followed their footprints out of the Tonduk River basin. One sample found 25 times higher amounts of manganese than is considered healthy for human intake by the Malaysian Ministry of Health.

“The [Tonduk River] water was always clear before a manganese mining operation began in the area in 2016,” Chow added. Now, the water fills with sediment with every rain.

Even though the mine was ordered to halt operations after the mysterious illness set in, headman Mahmet Pokok’s wife, Sinar says: “I’m still worried about Tonduk water. . . . We still don’t know what made us sick.” Despite their fears, Kuala Koh residents continue to use water piped in from the river. When it rains, they use rainwater collected in large plastic tanks. Meanwhile, the government is spending $800,00 to install a power grid and water treatment system.

But if the Health Ministry believes the deaths were truly because of measles, then why does the mine remain closed and a new water well with an electric pump been dug? Perhaps these measures were done out of an abundance of caution, or perhaps there were other reasons that have not been made public?

The Batek are at a crossroads, and there is lively discussion about their future as a people. They are only nominally engaged in the cash economy and lack any political representation. Their affairs with loggers and oil palm plantations are filtered through the government.

Li, still in his 20s, led me to the source of the river. “Sometimes, I get angry,” he told me, “about what has happened to us and our land, but we are powerless.”

This series was produced in partnership with the Pulitzer Center.

Johan Tahun takes a break atop the small concrete dam across the Tonduk River, built by the Malaysian government. (James Whitlow Delano/James Whitlow Delano)

Less than a generation ago, this land was a tropical rainforest and the Batek's territory since time immemorial. The thin tropical top soil immediately washes away, revealing a ruined landscape that will only support the oil palm trees with heavy use of chemical fertilizer, which washes into rivers. (James Whitlow Delano/James Whitlow Delano)

Nira was hospitalized for two months before recovering from the mysterious illness that struck this community of Batek in Kuala Koh. Symptoms included swollen throats and high fever, blurred vision with bloodshot eyes, and head and body aches. The stricken couldn't eat or drink. (James Whitlow Delano/James Whitlow Delano)

Li, a Batek villager, holds a medicinal herb, called “Pokok Baung,” just above the water source along the Tonduk River. After breaking off the root, the plant was replanted into the forest to regenerate. This was an area where the Batek would find medicinal plants, but since it has been logged, those plants died without the protective forest canopy filtering out the strong rays of the equatorial sun. (James Whitlow Delano/James Whitlow Delano)

A logging truck exits the rainforest. There seems to be no place for hunter-gatherers such as the Batek along the path Malaysia is blazing into the future. (James Whitlow Delano/James Whitlow Delano)

A mother and her two daughters wash pots and clothing at the water source that most Batek believe was contaminated by mining runoff. Despite that, they still use it as their primary water source. (James Whitlow Delano/James Whitlow Delano)

The Lebir River is choked with sediment from the undersoil, indicating it is anaerobic. This was the heart of the Batek’s territory. Kuala Koh sits upstream on a tributary. (James Whitlow Delano/James Whitlow Delano)

Angeni lost two sisters to the mysterious illness that swept through Kuala Koh in June. “I think about them every day,” she says. (James Whitlow Delano/James Whitlow Delano)

Hassan, left, and Li walk through the manganese mine processing area right above their Kuala Koh settlement. (James Whitlow Delano/James Whitlow Delano)

Johan Tahun looks into the main pit of the manganese mine that opened in 2016. (James Whitlow Delano/James Whitlow Delano)

Mahmet Om was stricken by the illness. He said he did not believe the Batek were infected by measles because Batek shamans were already quite familiar with measles and could treat the disease. This illness, he said, was different and new to them. (James Whitlow Delano/James Whitlow Delano)

Licensed logging continues on the fringes of Gunung Rabong forest reserve and Taman Negara National Park as a front loader puts logs onto a logging truck to be brought to a sawmill. (James Whitlow Delano/James Whitlow Delano)

The Malaysian rainforest was once vast. It still has sizable protected areas in the north of the peninsula such as Taman Negara National Park and Royal Belum State Park, photographed here. (James Whitlow Delano/James Whitlow Delano)

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