Abandoned for more than 50 years, and surrounded by Guyanese jungle, the manganese mine had become home to vast colonies of breeding bats and putrid piles of guano.
The group of men toiled in the four short tunnels for varying lengths of time, over nearly two weeks, clearing the mounds of waste, shovelling the dark red and black soil and crushing old concrete, in preparation for restarting operations. They wore no proper masks or Personal Protective Equipment (PPE).
Then, on the last Thursday of March 2019, six of the Chinese employees turned up sick at the nearby Pakera District Hospital, complaining of fever, coughing, headaches, weakness and joint pain. With the men’s hospitalisation prompting worries over H1N1 (Swine Flu) and leptospirosis, the heath chain of command was quickly notified and the emergency protocols activated.
The next day a patient died after his condition suddenly deteriorated, with major haemorrhagic and multi-organ failure. The remaining men were transferred to the Georgetown Public Hospital in the capital, where a second Chinese worker passed away in early April.
The close contacts of patients and healthy miners who had entered the same abandoned tunnels were placed under medical observation in the remote interior settlement. By mid-month, 16 cases were identified, including several Guyanese employees.
Spread across a series of nine hills within a prominent geological formation, the mining project in Matthews Ridge seemed an unlikely place for a medical mystery that would challenge experts in mainland China. The manganese ore strike extends for over 25 miles, and is part of the mineral rich-Guiana Shield. As the fourth most used metal by tonnage after iron, aluminium and copper, manganese is included within the group of valuable elements believed to have been chemically synthesised in massive stars, prior to a supernova explosion called a collapsar, that sent them across the cosmos to this planet and this particular place.
Reunion Gold Corporation, the Canada-based firm, which pursues the acquisition, exploration and development of mineral properties in the Shield region, announced in 2013, its promising results of a pre-feasibility study for the wholly-owned Matthews Ridge Manganese Project in northwest Guyana. Granted several prospecting licences, Reunion disclosed proven and probable mineral reserves of 26.3M tonnes, at the proposed open pit mine, and conventional washing and gravity plant processing 2.8M tonnes of ore per year, with an initial capital cost of US$233M and an internal rate of return of 15.7% based on price forecasts.
By the end of 2016, it had sold the stalled project to the Chongqing-based Chinese mining company, Bosai Minerals Group which agreed to pay US$10M dollars, comprising half in cash and the remainder in staggered payments from the sale of manganese, at the rate of US$2 per tonne of ore shipped from Matthews Ridge following the start of production. Bosai set up Guyana Manganese Incorporated to invest in the resuscitation of manganese mining and processing in Matthews Ridge, and export from the village of Port Kaituma.
The area’s fortunes have long hinged on mining. With the discovery of commercial quantities of manganese inland at Matthew’s Ridge, a canal was cut from the Kaituma River, and the Port constructed. Under the project run by a subsidiary of the American chemical giant Union Carbide, 1.7M tonnes of ore were transported in the 1960s, along a 40 mile-railway, bound for shipment by two converted Trinidadian tankers, from the Port to Chaguaramas Bay in north-west Trinidad, where it was distributed for industrial use with a large proportion going to Stavanger in Norway.
Bosai had been preparing the mines, when at the beginning of April 2019, the “cluster of febrile illness” struck, prompting the company to report to the China National Health Commission (NHC) and the China Center for Disease Control and Prevention (China CDC). The enterprise applied to the NHC for permission to evacuate about ten patients back to China aboard a medical aid aircraft, for treatment without causing any further transmission. A Chinese medical team of experts in epidemiology, medical bacteriology, clinical and emergency medicines was deployed to Georgetown, to provide support in clinical and public health, to identify the potential etiology and to assess the potential threat, especially the risk of international transmission.
According to a related online article in China CDC Weekly, co-authored by seven researchers including Lei Zhou of China CDC and Xiao-Ping Dong of the National Institute for Viral Disease Control and Prevention, various tissue specimens from the two fatal cases and blood samples from surviving patients were transferred to the laboratories of China CDC. Next-generation sequencing technology identified different lengths of specific gene sequences of a fungus Histoplasma capsulatum, in seven different samples. The eight other patients were clinically diagnosed.
Found in the droppings of bats, birds and rodents, especially in humid areas, cases of histaplasmosis have been reported in every continent except Antarctica but are fairly rare in China, the team said.
“High prevalence of histoplasmosis has been observed in Central America, Caribbean, and South America. Infections of Histoplasma are acquired through a respiratory route, particularly inhalation of aerosols from disturbed soils enriched with excreta from birds and bats. These infections are most common in persons involved with removing soil, visiting caves, cleaning old houses, or felling trees, etc.”
The experts noted that this is the first report of cluster infections of Histoplasma among overseas Chinese workers. “Long labour times, repeated entering of contaminated tunnels, working in high-dust environments are likely to result in earlier illness onsets, more severe clinical courses, and even fatal outcomes. More importantly, none of the patients used reliable personal protection equipment (PPE), such as common masks while working, that would prevent the inhalation of more Histoplasma spores,” the team observed.
Stating that the outbreak “expands our knowledge of the control and prevention of fungal disease in China,” the team stressed that the investigation highlights a probable risk of infection with Histoplasma when entering without PPE into an environment with bats, such as caves or mines. Effective education and communication might therefore be needed among residents and travellers, it added.
In their report, the investigators revealed that during an interview with the staff in the local hospital, “we learned that there was a local farmer who underwent similar but mild pathogenesis after entering the same tunnels and collecting feces of bats as fertilizer, highlighting the possibility of a long-term circulation of Histoplasma in this region.”
“To our knowledge, no definitively confirmed cluster infection of Histoplasma in China has been reported. Despite that, there have been a few similar events that occurred in travellers in the caves in the southwestern region of China, inhabited (by) various species of bats, though no reliable pathogen evidence has been obtained. The clinical findings of the cases provide valuable experience to Chinese clinicians to understand the clinical features of acute infection of Histoplasma and will help achieve early detection and efficient treatment for patients,” the group said, warning that, “Due to worldwide industrial collaborations and travelling, we to need watch closely for emerging pathogens.”
In May, the Guyana Government, through an advertisement notified the public, that Guyana Manganese Inc. which was shut down after the outbreak, has had its Environmental Impact Assessment (EIA) for the Region One project approved by the Environmental Protection Agency (EPA). There was no mention of the deaths or the outbreak, but the notice said workers will be equipped with necessary PPE in the execution of their duties.
ID avoids bat-infested caves and tunnels. She continues to wear a suitable mask – despite being vaccinated with both Astra Zeneca COVID-19 shots – and a manganese-coloured amethyst ring.