Program: safe water, health education, case management and close surveillance to eradicate guinea worm (aka dracunculiasis)

In a nutshell The Problem: Guinea worm can cause severe short-term pain and debilitation, often leaving people bedridden for upwards of a month. More on symptoms here. The Program: Providing wells, water filters, health education, case management, and heavy monitoring to eradicate the disease. Track record: This program is credited with nearly eradicating guinea worm: reducing global prevalence from 3.5m cases in the mid-1980s to fewer than 5,000 today. However, completing eradication could be difficult (see our discussion of eradication programs). Cost-effectiveness: We estimate that this program to date has cost $5-8 per serious case of guinea worm averted, a very strong result (if not one that is easily comparable to other programs' effects). Completing eradication could have very different cost-effectiveness (see our discussion of eradication programs). Bottom line: This program to date is one of the success stories of global health. We are not sure about the case for pursuing complete eradication from here.

Table of Contents

Basics of the program

What is the program? What problem does it target?

Guinea worm is a disease passed through contaminated water, causing severe pain and debilitation--often leaving people bedridden for over a month. (More on the guinea worm.)

The global program to eradicate guinea worm consists of:

  • Safe water:1
    • Application of larvacide to contaminated water.
    • Construction of wells and boreholes.
    • Provision of cloth filters to prevent transmission.
  • Health education: To promote use of the cloth filters when drinking and to encourage reporting all cases.2
  • Careful monitoring of cases:3 The historical, archived reports are available online at the CDC website.4
  • Case containment: Preventing those who are infected from entering the water (which would lead to contamination and further transmission).5

What are the components required to implement this program - how does it work?

Workers need to dig wells, provide water filters, provide health education, contain cases, and monitor and report new cases. These duties have largely been carried out by local volunteers, who have been trained and supervised by ministries of health.6

Program track record

Micro evidence: Has this program been rigorously evaluated and shown to work?

We have not identified any rigorous studies of this program. A literature review on the relationship between water/sanitation and disease transmission7 cites two studies with suggestive (though not highly rigorous) evidence for the idea that borehole construction is effective:

  • One study evaluated the impact of improved water sources on guinea worm in Nigeria. The analysis compared guinea worm prevalence in 20 communities that had improved water supplies and health education to 5 that did not, and found that "Use of borehole water reduced the incidence of dracunculiasis by 81%."8
  • A study in Uganda surveyed over 2,000 people and examined results by season. "During the rainy season the attack rate among borehole users was one-tenth of that among non-users, while during the dry season it was two-fifths that of non-users."9

Macro evidence: Has this program played a role in large-scale success stories?

This program has virtually eradicated guinea worm, reducing the number of cases worldwide from approximately 3.5 million in 1986 to fewer than 5,000 in 2008. In 1986 there were 20 endemic countries; in 2008 there were 6.10

The Carter Center is credited with leading this initiative.11 The Carter Center provides charts of progress in fighting the disease over time.

Recommendations and concerns

Do expert reviews of the comparative merits of interventions endorse this one?

See sources consulted.

The Copenhagen Consensus and Jamison 2008 don't address this disease, perhaps because it's so close to eradication. The Disease Control Priorities in Developing Countries report discusses guinea worm but does not recommend focusing on disease eradication (see next section).

What are the potential downsides of the intervention?

At this point the disease is extremely rare, and focusing on eradication could consume large amounts of resources towards a cause that may ultimately fail. More at our discussion of eradication programs.

Cost-effectiveness

Eradication efforts are currently ongoing, and given that success is not assured, it's difficult to estimate cost-effectiveness for the effort as a whole. We estimate cost-effectiveness for the campaign to date.

Impact: The Center for Global Development's case study estimates that there were 3.5 million cases of guinea worm per year (worldwide) before the eradication program began; in 2008 there are fewer than 5,000.12 It estimates that 58-76% of such cases are severe.13

Cost: The total cost for the guinea worm program from 1987-1995 was $87.5 million;14 as of 2004, the estimated cumulative cost was $125 million.15 A Carter Center representative estimated the annual cost of the program at $10-15 million.16

Cost-effectiveness estimate: The numbers above imply $2.85-$4.28 per case averted; $4-8.50 per severe case averted.

Future cost-effectiveness could be very different from past cost-effectiveness; see our discussion of eradication programs.

Sources

  • 1
    • "To improve the safety of water in endemic regions, the national programs facilitated the construction and maintenance of accessible water sources (mainly wells) and the selective application of ABATE larvicide, which can effectively kill the copepods, or “water fleas,” in ponds and other stagnant sources of drinking water. Construction of safe water sources is the most expensive and long-term option of all the available interventions and has received sizable financial support from UNICEF and the government of Japan." Levine 2007, Pg 4.
    • "One of the most cost-effective ways of improving the safety of drinking water (to prevent guinea worm disease) is by passing it through a cloth filter. At the start of the eradication campaign, efforts relied on filters made of local fabrics. However, the cloth fabric clogged frequently, and these filters often were used instead as decorations." Levine 2007, Pg 4.
    • "A new nylon cloth that was less prone to clogging was developed in the early 1990s." Levine 2007, Pg 5.

  • 2

    "The public education interventions have convinced individuals and communities that they can prevent the disease and its spread. Individuals are encouraged to clean drinking water by passing it through a nylon filter, to avoid recontamination of ponds, and to report infestations. An extensive social marketing campaign has been employed with the goal, in the words of Dr. Hopkins, that 'No individual would be able to approach a drinking water source without thinking of guinea worm disease.' The simple, targeted messages are communicated through radio, T-shirts, posters, banners, stamps, sides of vehicles, and videos." Levine 2007, Pg 5.

  • 3

    "Instead, eradicating guinea worm would require the disruption of the worm's transmission for one year through the principal interventions: provision of safe sources of drinking water; treatment of unsafe sources of drinking water with larvicide; health education and social mobilization to keep those infected from contaminating sources of drinking water and to ensure filtration of household drinking water; and surveillance and monthly case reporting." Levine 2007, Pg 3.

  • 4

    Centers for Disease Control, "Guinea Worm Disease Wrap Up Archive."

  • 5
    • "The campaign promoted improved water safety through deep-well digging, environmental control, and the use of cloth filters for drinking water; health education programs; and case management, containment, and surveillance." Jamison et al. 2006, Pg 167.
    • "To ease the burning pain, infected individuals frequently submerge the blister in cool water, causing the blister's rupture and the release of hundreds of thou- sands of larvae into the water. A vicious cycle of reinfection occurs when sufferers inadvertently contaminate sources of drinking water and set the stage for themselves and other residents to contract the infection." Levine 2007, Pg 2.

  • 6

    "Trained and supervised by representatives from the ministry of health, the village volunteers form the bulk of the eradication staff and perform a range of key functions including daily detection of cases, case management, containment of transmission, distribution and replacement of nylon cloth or pipe filters, and social mobilization and public awareness campaigns. These village volunteers are the keys to success of the monthly reporting system that provides national coordinators with data necessary for tracking the disease and monitoring the campaign's progress." Levine 2007, Pg 5.

  • 7

    Esrey 1991.

  • 8

    "In Nigeria (21), the impact of a UNICEF-assisted rural water project that provided boreholes and hand pumps along with health education, was evaluated. Prior to the intervention 8.600 subjects, and 3 years after its installation, over 10,000 were examined. The study comprised 20 serviced and five unserviced communities. Use of borehole water reduced the incidence of dracunculiasis by 81%." Esrey 1991, Pg 614.

  • 9

    Esrey 1991, Pg 614.

  • 10
    • "The result of the campaign's efforts has been a 99 percent drop in the prevalence of guinea worm. In 2005, only 10,674 cases of the disease were reported, compared with an estimated 3.5 million infected people in 1986. All three countries in Asia are now free of guinea worm: Pakistan (1993), India (1996), and Yemen (1997). As of 2005, 11 of the original 20 endemic countries halted transmission of the disease; 4 reported fewer than 100 cases each, and just 2 had more than 1,000 each. The vast majority (89 percent) of the cases reported in 2005 were from Sudan (5,569 cases) and from Ghana (3,981 cases) (see Box 11–1). In the absence of the eradication campaign begun in 1986, a total of 3.5 million cases of the disease would have presumably occurred annually. Therefore, the eradication campaign can be said to have prevented at least 63 million cases of guinea worm disease since 1987." Levine 2007, Pg 6.
    • See Carter Center, "Distribution by country of 4,619 cases of indigenous cases of dracunculiasis reported during 2008," for data from 2008.

  • 11

    "A major turning point in the campaign occurred later in 1986 when US President Jimmy Carter began his nearly 20-year involvement in the campaign and became a powerful advocate for eradication, with the Carter Center taking the role of lead nongovernmental organization providing financial and technical assistance to national eradication programs." Levine, 2007, Pgs 3-4.

  • 12
    • "The result of the campaign's efforts has been a 99 percent drop in the prevalence of guinea worm. In 2005, only 10,674 cases of the disease were reported, compared with an estimated 3.5 million infected people in 1986. All three countries in Asia are now free of guinea worm: Pakistan (1993), India (1996), and Yemen (1997). As of 2005, 11 of the original 20 endemic countries halted transmission of the disease; 4 reported fewer than 100 cases each, and just 2 had more than 1,000 each. The vast majority (89 percent) of the cases reported in 2005 were from Sudan (5,569 cases) and from Ghana (3,981 cases) (see Box 11–1). In the absence of the eradication campaign begun in 1986, a total of 3.5 million cases of the disease would have presumably occurred annually. Therefore, the eradication campaign can be said to have prevented at least 63 million cases of guinea worm disease since 1987." Levine 2007, Pg 6.
    • See Carter Center, "Distribution by country of 4,619 cases of indigenous cases of dracunculiasis reported during 2008," for data from 2008.

  • 13

    "Two studies in Nigeria, for example, reported that 58 percent to 76 percent of patients were bedridden for at least one month following the worm's emergence." Levine 2007, Pg 2.

  • 14

    "The estimated cost of the global campaign between 1987 and 1998 is $87.5 million." Levine 2007, Pg 6.

  • 15

    "The estimated cumulative cost of the campaign as of 2004 was approximately $25 million." Levine 2007, Pg 1.

  • 16

    Phil Wise, phone conversation with GiveWell, February 2, 2009.