After a magnitude 7.0 earthquake rocked Haiti in January, many experts worried that devastating outbreaks of infectious diseases would soon invade the region. In a nation where a large part of the population already lived without access to reliable sanitation and clean water, a disaster that further disrupted infrastructure seemed likely to lead to widespread infections, such as cholera, which spreads through feces-contaminated water. Although more than a million people are still living in tent encampments following the disaster, it was not until late last week that news of a potential cholera outbreak first emerged.
Some 259 people have died from the bacterial infection so far and another 3,342 have been sickened, according to Haiti's Ministry of Health, the BBC reports. Officials fear that the outbreak, which seems to have started around the Artibonite and Plateau Central regions, north of the capital, Port-au-Prince, could become endemic to the city, where about 89 percent of residents live in slums or slum-like conditions. Five people there have been diagnosed with the disease, according to the World Health Organization (WHO), but they likely contracted the illness before arriving in the capital.
"There are limited ways you can wash your hands and keep your hands washed with water in slums like we have here," Michel Thieren, an official from the Pan-American Health Organization, told the Associated Press.
The cause of the disease is the bacterium Vibrio cholerae, which releases a toxin that triggers severe diarrhea and rapid dehydration; both effects can quickly prove deadly. Cholera might sound like an ailment that was dispatched in 19th century, but it still infects some three million to five million people worldwide and kills at least 120,000 each year, mainly in India and sub-Saharan Africa.
Although the number of people who have died from the disease in Haiti is lower so far today than it had been over the weekend, the country is still bracing for further spread. "We are preparing ourselves for the worst case scenario, which is a cholera outbreak in the whole country," Michel van Herp, of Doctors Without Borders, told BBC News.
But why is the outbreak just now emerging in Haiti, and how is cholera still a global concern? Scientific American spoke with David Sack, a professor in Global Disease Epidemiology and Control at Johns Hopkins Bloomberg School of Public Health, to learn more about the disease and what is being done to control it.
[An edited version of the transcript follows.]
Why do you think this outbreak is happening now, more than nine months after earthquake?
I wish I knew more about the events that led to this outbreak. From what I can gather, the outbreak did not start in the area of the earthquake, so it's not clear that it is directly related to the earthquake. We don't know whether it was introduced or if the bacteria was indigenous to the area and had never been spread before.
Is the current outbreak likely linked to long-term use of these tent-based refugee camps?
The refugee situation makes it much more dangerous, but I'm not sure that's what started the outbreak. You need to have the organism there circulating first. And of course we haven't seen cholera in Haiti for many, many years. Even in the 1990s outbreak in Latin America, it did not jump across to the Caribbean islands.
So how is cholera usually spread?
It is fecal-oral. So the feces get into the food or water supplies, though mainly the water. There is also an environmental reservoir, so it usually starts in the environment.
Cholera can kill within a matter of hours. Who is most at risk for getting—and dying from—cholera?
Anybody can be at risk—it's one that can kill healthy people quickly. We usually think a lot of these diseases will preferentially hit the malnourished or otherwise vulnerable. But cholera is something that can affect anybody.
The main risk factors are people whose stomachs, for whatever reason, are not making the normal amounts of gastric acid—if someone has recently had stomach surgery or is taking drugs that inhibit the production of gastric acid. The other risk factors are genetic, which unfortunately there isn't much you can do about. If your blood type is O, you're at higher risk. When cholera struck Peru, the indigenous people there virtually all have blood type O, and they were at higher risk.
In terms of risk for death, it is people who don't have treatment available. If they don't get treatment in a very short amount of time, they have a very high risk of dying.
Are rehydration therapy and antibiotics the best treatments out there?
Yes. But what I have not seen is what the sensitivity pattern is for the antibiotics. We've seen in previous outbreaks that people don't know what the patterns are and they ship the wrong antibiotics.
So different antibiotics are needed to treat different strains of cholera?
Yes. That's why it's important to know the sensitivity of this strain. And you have to keep monitoring it because it could change in the future.
What are the best ways to keep the disease from spreading to more people? Is it mostly an issue of clean water?
There are different ways of making your water clean. One thing I haven't seen out there so far is consideration of the vaccine, which is available now. It has only been since March this year that the World Health Organization has recommended the use of the cholera vaccine on a wide scale. I think this is a situation where it might be considered.
From the numbers that have come out so far, it seems that there's been a mortality rate of roughly eight percent. Is that a pretty standard number of expected deaths?
Standard mortality should be zero. I've worked in Bangladesh for many years, and in our hospital, we treated thousands of patients, and nobody died of cholera. So no deaths are inevitable if you provide the right treatment.
Nobody's had much experience with it in Haiti, so case mortality rates become very high at first, but as facilities become more experienced and people learn where to get treatment, the case mortality rates should come down very quickly.
Cholera seems like a disease of the past—will it ever be eradicated?
No, because of its environmental reservoir. I don't see any way we could eradicate it like eradicating polio or smallpox. As long as you have an environment, you will have cholera.
How does Haiti's outbreak compare with others in recent years?
In Bangladesh, we have thousands of cases every year, but it doesn't make it into the newspapers because we have it every year.
Theoretically, governments and health ministries are supposed to report cases to WHO, but in general many of them don't do it at all. Cholera is a very sensitive subject. Many countries just don't want to report it for fear of its impact on trade and travel—and that used to be a reasonable fear, but I'm afraid now that they haven't been reporting it because it's become a tradition.
In the past we used to assume that cholera outbreaks would arise quickly then go away quickly—and by "quickly" I mean one to two months. But the outbreak in Zimbabwe a year ago has taught us that cholera outbreaks can persist for a year. I think it's becoming harder to predict how long we can expect this outbreak to persist.
Is that because we have a better understanding now about the outbreaks, or has there been a change in the disease spread itself?
It seems to be a difference in how it's transmitted, not so much our understanding. It's behaving differently now than it did in the past. Clearly it keeps changing its genetics. So, for example, recently the toxin that the organism produces has changed genetically, and it appears that the change has resulted in a more severe illness. But this organism is in the environment, and its genes are exchanged frequently with the environmental strains, so there's a lot of re-sorting that's going on. And when people get infected, the people themselves act as the amplifier and selector of the most virulent strain.
After the 2010 earthquake, Gheskio’s multi-acre campus was badly damaged. So the organization erected emergency tents to serve as a makeshift cholera treatment clinic. Once cholera reached Port-au-Prince, patients showed up on foot or were carried in wheelbarrows, around the clock.
Cholera manifests with extreme diarrhea and vomiting. Virtually all liquid is excreted from the body, causing victims to die of dehydration within hours of full manifestation if untreated. It is relatively easy to treat, but patients must be rehydrated immediately. To prevent it from spreading, infected human waste must be managed carefully.
Gheskio’s founder, Jean W. Pape, an infectious disease specialist and native of Haiti, knew that eradicating cholera would take years. So even as the organization struggled to keep up with the influx of patients during the first year of the epidemic, he embarked on a long-term solution: building a permanent treatment center.
Gheskio turned to MASS Design Group, a Boston-based nonprofit organization that specializes in architecture that promotes dignity and justice in resource-limited settings. It has built hospitals, health-worker housing, schools and civic spaces around the world, including a tuberculosis hospital for Gheskio. MASS Design began by studying the conditions inside the tents.
Tents provide relative shade and privacy but offer limited light and poor ventilation, trapping warm air and compounding the smell of bodily waste. The materials become worn by rain, wind and sun, and must be replaced routinely. Because of the nature of cholera, the makeshift beds, fashioned out of old fiberglass school chairs and costly army cots, also didn’t last long.
Most problematic, Gheskio was relying on manual removal of human waste by an outside vendor. This was both costly and risky: The organization couldn’t ensure its disposal would not recontaminate the water table, risking the infection of others.
“We did some back-of-envelope calculations and found that over a 10-year span of time, which was then considered optimistic for how long it would take to get rid of cholera, the tents and manual waste disposal system they were then using would cost Gheskio in excess of $500,000,” according to a co-founder of MASS Design, Alan Ricks.
Ricks estimated that MASS Design could build, for a comparable sum, a permanent structure that could be repurposed once the epidemic was fully contained. So MASS Design and Gheskio joined forces to raise philanthropic funding from the Deutsche Bank Foundation, Barr Foundation and individual donors, and began work.
One important innovation, developed with Fall Creek Engineers, based in Santa Cruz, Calif., was to bring a water-purification technology to Haiti called anaerobic baffled reactors. The reactors are a form of septic system that uses bacteria to treat sewage and contaminated water, turning it into clean water. Reactors, buried under the cholera center, force water through five chambers, each successively increasing the level of purification.
Each week, Pape receives a detailed report on the water quality. The system sanitizes and recycles 250,000 gallons of water annually, ensuring that the water is free enough of bacteria and other pathogens that it can be returned to the water table. This output is supplemented by separate, large cisterns to capture rainwater for drinking.
Many other details incorporated into the center also promote health, as well as comfort, beauty and pride. Above the reactors, for example, is a pavilion structure designed to maximize airflow. Rather than spending money on tents, furniture or waste disposal services — money that leaves the local economy — the organizations enlisted local artisans, whose metalwork is world renowned, to create perforated metal sheets, painted a chorus of blues, to wrap the building exterior. Waffle-like patterns of these sheets can be opened and closed to provide shade and privacy, or sealed completely during storms, as they were when Hurricane Irma neared Port-au-Prince last week.
The airflow is aided by large-diameter fans, like those in gyms and airports. The cement floor is smooth, free of crevices where bacteria can congregate, and sealed with epoxy. MASS Design interviewed many patients and staff members in an effort to design and create prototypes of beds that would be comfortable as well as easily sanitized and reused.
“What I love about MASS is their attention to detail,” Pape said. “They asked us everything that work and everything that doesn’t work. But most importantly, they are problem solvers.”
“The building looks absolutely extraordinary,” said Roger Glass, a cholera expert who is director of the Fogarty International Center for Advancing Science for Global Health at the National Institutes of Health and has visited the Gheskio campus. “For ventilation and coolness, it’s tremendous.”
Before encountering a hospital that MASS Design developed in Rwanda, Glass said, he had not seriously considered the relationship between health outcomes and building design. “If you had called me seven years ago to talk about buildings and health, I would have blown you off,” he said. Today, Glass is eager to see more collaborations with human-centered design firms, like MASS Design, in the field of global health.
Comparing the treatment center to the tents, Pape is blunt: “It was like going from hell to paradise.”
Amie Shao, who helped lead MASS Design’s work in Haiti, reflected: “When we started, our goal was simply to help Gheskio do their work better in treating their patients in a more dignified setting. We realized, however, that architecture could not only help treat these diseases after the fact, but prevent the spread of disease in the first place by controlling recontamination. In all of our work, we seek to proactively challenge many of the underlying risks and issues that global health faces.”
To be sure, the cholera treatment center is not solely responsible for halting the spread in Gheskio’s target area. Gheskio also developed a robust water chlorination program and maintains its own factory to produce chlorine. The organization also supports and participates in broad efforts by the Ministry of Health to raise public awareness about symptoms and the risk of contamination throughout the country.
And Gheskio joined forces with Partners in Health to get cholera vaccines approved in Haiti. Euvichol, a vaccine that can be administered orally and lasts up to 30 days without refrigeration, costs less than $2 per dose. “We would need a budget of less than $50 million for universal coverage for all of Haiti,” Pape estimates.
Gheskio’s Cholera Treatment Center was ultimately built for $750,000. Pape now predicts that the organization will have recouped that cost in just three years. Haiti needs a modern, countrywide water and sanitation system, but it’s unclear where the money will come from. In the meantime, Gheskio’s center has saved many lives.
By uniquely combining patient care with on-site water treatment, Gheskio’s center also holds lessons for other regions struggling to contain cholera or facing it in the future. Globally, the World Health Organization estimates there are between 1.3 million and four million cases of cholera annually in 42 countries, with 21,000 to 143,000 cholera-related deaths each year. This year, Somalia saw a major resurgence of the disease, with over 50,000 people infected. About 1,000 died.
In the three years since Gheskio’s Cholera Treatment Center opened, the facility has remained in constant use because those outside the organization’s target area continue to be exposed to contaminated water. It has admitted over 10,000 patients to date, including over 7,000 who were hospitalized. Eighty-three percent of those patients came from outside of Gheskio’s catchment area.
While cholera reports in Haiti were on the rise in 2015 and 2016 at upward of 25,000 cases annually, the country saw a decrease in 2017, which Pape attributes to higher-than-normal rainfall in the region. Of the 100 beds, no more than a third were occupied at any time this year, with as few as a handful of patients at times. The risk for outbreaks remains high, however, and the disease’s countrywide eradication is still years away.
“Haiti’s recently elected government, and the president particular, is focused on universal oral cholera vaccine as well as home chlorination,” Pape reports. “If we get the vaccines and if we pursue home chlorination, I truly believe we can rid of cholera within four to five years.”Continue reading the main story