Turning the tide

In the narrow, winding stone-alleys of Zanzibar City, Jamal Ally savours the cool morning sea breeze, all the while aware that the silent menace of "snail fever" still undermines the health of the island's inhabitants. 

As the midday sun blankets the coastal town in heavy, humid heat, Ally thinks about the inland stream that has always been his cooling refuge, a sanctuary where he can escape the unrelenting Zanzibari sun. 

"Within days of exposure to contaminated freshwater, I developed severe bloody urine and a fever, and soon learned I had schistosomiasis (bilharzia), a serious threat to my health," Ally told ChinAfrica. A fishmonger at Malindi Fish Market, he described his ordeal as excruciating, feeling as if the disease was dragging his vital organs down, leaving him powerless against the invisible parasitic toxin that sapped his strength and vitality. 

He explained that schistosomiasis is a waterborne parasitic disease that has long plagued Zanzibar, especially rural communities where residents depend on rivers and unsafe wells, putting themselves at risk of infection. 

For Natalie Amour, the waters concealed a silent predator: a microscopic fluke that put her motherhood at risk. She realised she had schistosomiasis when she began experiencing sharp pain beneath her belly button. Amour, 20, recalls frequently visiting hospitals for treatment of water-related illnesses. "I was told it might stop me from having children. I was scared, because I have always wanted to be a mother," she said. 

The debilitating disease also nearly derailed the academic ambitions of 20-year-old Hamed Abdallaar. Painful urination forced him to spend much of his school day in the toilets, making it almost impossible to focus in class. "I could hardly concentrate because I was constantly rushing to the toilet, and the pain made it even harder to keep up with my schoolwork," said Abdallaar, now a second-year student at the State University of Zanzibar. 

The experiences of these residents highlight the real dangers of inadequate access to clean water. Ensuring proper sanitation and effective water management is essential to safeguard the health of the community. 

That's why the China-supported schistosomiasis control project, carried out in partnership with the World Health Organisation (WHO) and the Zanzibar government, represents a critical push to provide treatment and medical resources - saving lives across Tanzania. 

Effective control 

In 2014, China signed a memorandum of understanding on the prevention and treatment of schistosomiasis in Zanzibar at the World Health Assembly, pledging to provide financial and technical support for Tanzania in that regard.  

In 2017, the first batch of experts from the Jiangsu Institute of Parasitic Diseases of China was dispatched to Pemba Island to help local people to fight the disease. To date, 34 experts have been dispatched to carry out schistosomiasis control work on the island.  

The second phase of the China-Zanzibar schistosomiasis control and elimination project commenced in September 2023 on the fringes of Pemba Island, where the beauty of the freshwater streams has long been deceptive. 

A key innovation in Phase II has been the construction of safe water supply systems. Five projects, four on Pemba Island and one on Unguja Island, now serve about 30,000 people in total, said Wang Wei, a professor at the Jiangsu Institute of Parasitic Diseases. 

Wang, who leads a five-member Chinese expert group, noted that by combining safe water supply systems with disease treatment, snail control and health education, the project has significantly reduced infection rates while improving livelihoods, such that for women, who bore much of the burden of fetching water and caring for children, the change has been transformative. 

Wang said that in Unguja alone, 18,000 residents benefitted from clean, accessible water, cutting off disease transmission at its source while also reducing other water-related illnesses such as intestinal infections and cholera. 

"China's experience in schistosomiasis control has already proven to be effective and scalable," said Wang. 

The latest project data reveal that Phase I of the project, implemented on Pemba Island from 2017 to 2020, reduced infection rates in demonstration areas from 8.92 percent to 0.64 percent, meeting WHO standards for eliminating schistosomiasis as a public health problem. Phase II, launched in 2023, expanded coverage to Unguja Island. 

Baseline surveys in Unguja recorded an infection rate of about 1.23 percent. Within two and a half years, that figure dropped to just 0.15 percent, well below the WHO threshold of 1 percent. 

Integrated approach 

Beyond infrastructure, Huang Yuzheng, a lead expert of the project, stressed that controlling schistosomiasis requires more than treatment alone. He said an effective response depends on a comprehensive approach that brings together health education, information technology and integrated management to tackle the disease at its source. 

Huang said the next milestone is set for 2026, when a fully digital schistosomiasis surveillance and response system will go live. 

"The Chinese expert team's dedication to saving lives and caring for the sick, along with their deep compassion, will be remembered by the people of Zanzibar," said Nassor Ahmed Mazrui, Zanzibar's minister of health. Mazrui said the partnership with Chinese experts has helped Zanzibar to establish a community-based model for schistosomiasis control, centred on local hospitals and health volunteers. 

Tanzania's Zanzibari President Hussein Ali Mwinyi recently thanked the Chinese medical team for their contributions to controlling and eliminating schistosomiasis on the island. 

"Our profound gratitude goes to China for its selfless assistance to Zanzibar in the medical and public health sector over the years," Mwinyi said.