Cholera: The Forgotten Pandemic
Updated 22 October 2018
Many people think of cholera as a 19th century disease. This is true for high-income countries. But elsewhere, cholera never went away. The current pandemic - the 7th that has been recorded - has been ongoing since 1961. It is the world’s longest running pandemic.
Over the last year, cholera (or suspected cholera) outbreaks have struck in Algeria, Angola, Bangladesh, Burundi, Chad, the Democratic Republic of the Congo, Djibouti, Ethiopia, Kenya, The Kingdom of Saudi Arabia, India, Malawi, Mozambique, Nigeria, Niger, Somalia, Sudan, South Sudan, United Republic of Tanzania, Uganda, Yemen, Zambia, and Zimbabwe, while the long-running outbreak in Haiti continues.
Cholera sickens approximately 2.9 million people every year, and kills 95 000. The disease is endemic in more than 47 countries across the globe. In Africa alone, more than 40 million people live in cholera “hotspots” where outbreaks are a regular occurrence. Factors driving the outbreaks include climate change, forced migration, prolonged conflict, urbanization, population growth, and poor access to health services. Fundamentally though, cholera is the result of a lack of adequate water and sanitation.
Cholera is spread when people consume contaminated food or water. To put it bluntly, cholera spreads when people have no choice but to eat food or drink water that contain faeces. It is an acute diarrhoeal disease that can kill within hours if left untreated. Today more than 2 billion people worldwide drink water from sources contaminated with faeces, and 2.4 billion are without basic sanitation facilities.
While the underlying causes of cholera have deep roots, there are also solutions within reach.
Cholera is preventable and manageable
There are new tools to prevent infection, such as the Oral Cholera Vaccine, and inexpensive, efficient treatments that have been available for decades, in particular oral rehydration solution. But the health sector alone cannot prevent and control cholera outbreaks. The best way to prevent cholera, and other water-borne diseases, is with the investment and maintenance of community-wide water, sanitation and hygiene facilities. Peru, Viet Nam and Senegal are examples of countries which have largely eliminated cholera outbreaks, after investing in water and sanitation infrastructure and implementing targeted public health interventions.
Ending Cholera: A Global Roadmap to 2030
Ending Cholera: A Global Roadmap to 2030 is a new global strategy for cholera control at the country level, developed by health and development organizations, including WHO, through the Global Task Force on Cholera Control. The goal is to reduce cholera deaths by 90%, and to eliminate disease transmission in as many as 20 countries by 2030. The Roadmap proposes that more effective control will be achieved through targeted and sustained preventive interventions in cholera hotspots, including the provision of clean water, adequate sanitation and hygiene facilities and access to oral cholera vaccine. The Roadmap was endorsed this year at the World Health Assembly as part of a global resolution to address cholera.
Many challenges remain. For countries struggling with protracted humanitarian crises, controlling cholera can be extremely difficult. Over the past year, Yemen has faced a cholera epidemic with more than 1 million suspected cases and more than 2000 deaths. Haiti, meanwhile, has had over 800 000 cases and nearly 10 000 deaths since 2011.
“Vaccination will not solve the cholera problem but only buy us some time. Unless we plan mid- and long-term water and sanitation interventions, cholera is going to reappear as soon as immunity to the vaccine wanes. There are no shortcuts.”
Dr Legros, WHO cholera team lead
Fundamentally, cholera is the result of a lack of investment in adequate water and sanitation infrastructure, maintenance and governance – all of which are needed to solve the problem. Countries’ investments in long-term interventions for cholera control would need to be three times higher than current levels to achieve the 2030 SDGs. Global water and sanitation aid has declined in recent years, dropping from $10.4 billion in 2012 to $8.4 billion in 2015.
Supporting patient care to reduce mortality is perhaps the most critical intervention that can be made in the short-term in response to an outbreak, said Dr. Dominique Legros, who leads the WHO cholera team. Among refugees, who are particularly vulnerable to cholera outbreaks because of their crowded conditions and poor water, sanitation and hygiene facilities, proper treatment of the disease has made a real difference. In decades past, case fatality ratios were sometimes as high as 30%. Since 2009, the ratio of deaths from cholera is estimated not to have exceeded 2% in those settings.
WHO support on cholera ranges from providing technical guidance, coordinating with global partners, and providing supplies and training. Examples include the following:
- In the last year, WHO has airlifted tons of supplies to cholera treatment centers, including intravenous fluids and oral rehydration solutions, water purification tablets, antibiotics, and protective equipment.
- Supported treatment centres in Yemen, Nigeria and the Democratic Republic of the Congo.
- Trained health workers on WHO case management, infection prevention and control standards, most recently in Gaziantep, Turkey, for Syrian health workers.
- Run health education campaigns for at-risk populations in Nigeria which have reached reached 798 000 people in camps and host communities across Maiduguri Municipal Council, and Jere, Konduga, Mafa and Dikwa local government areas.
Meanwhile, the demand for the oral cholera vaccine has increased significantly as many countries are using this method to halt transmission in high-risk communities. More than 28 million doses of oral cholera vaccine have been shipped from the global stockpile for use in mass vaccination campaigns. But cholera experts warn that the vaccine is not a replacement for adequate water and sanitation.
“Vaccination will not solve the cholera problem but only buy us some time,” said Dr Legros. “Unless we plan mid- and long-term water and sanitation interventions, cholera is going to reappear as soon as immunity to the vaccine wanes. There are no shortcuts.”