1. Schistosomiasis: An unfamiliar infectious disease
Tiffany Jackson, Ph.D. student (Public Health: Epidemiology)
Walden University
PUBH (Environmental Health)
Instructor: Dr. Shana Morrell
Spring, 2009

2. Objectives Educate the general public about Schistosomiasis
Enlighten the public about a potential global impact
Convince professionals of the need for public health interventions
Schistosomiasis is a health issue that is not well known, but demands that public health professionals pay more attention to it. My presentation is geared towards educating the general public as well as the organizations that are aware of this parasitic infection, but may not be fully aware of the potential global impact this infection may have. The intended audience includes individuals from the Global Health Council, World Health Organization, The Centers for Disease Control and Prevention: Division of Parasitic Diseases and the Directors of Health Promotion and Education. The goal of this presentation is to possibly convince these organizations to work together in order to find affect methods for reducing the incidence and prevalence of Schistosomiasis worldwide.

3. Why Is It Important? Emerging Infectious Disease ???
Socioeconomic Impact
Health Conditions
The essential question for public health professionals is, why is this a problem?
Schistosomiasis infections affect so many people around the world. The global community is getting smaller and the spread of infectious agents has become easier. This particular parasite is finding its way to travel to many parts of the world that previously had no knowledge of its existence.
One of the possible ways to spread the infection is through the growing popularity of wilderness tourism. The increase in travel abroad exposes more travelers to the infecting parasites. For example, the Directors of Health Promotion and Education reported that schistosomiasis has been found in U.S. river rafters in Africa (2005). The tourists who swim in these contaminated waters, Peace Corps volunteers and others who had contact with fresh water in areas are the ones that can contract schistosomiasis in multiple tropical climates (DHPE, 2005).
There are four main conditions associated with schistosomiasis infections. The four conditions are Dermatitis, Katayama Fever, Chronic Fibro-Obstruction Schistosomiasis and Bladder carcinoma. The severity of these conditions ranges from minor to fatal.
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from

4. Schistosomiasis What Is It? How Do People Get It? Where Is It Found?
An infection caused by blood flukes
How Do People Get It?
Contact with contaminated water
Where Is It Found?
Tropical Climates
Schistosomiasis, which is also called bilharzia, is an infectious disease caused by parasitic trematode worms known simply as “blood flukes”. Schistomes are the type of blood flukes that causes Schistasomiasis, an infection of the blood. This is the only trematode infection that is known to occur through the skin. The parasite is contracted when human skin comes into contact with infected water (CDC, 2005). Snails are known to be the carriers of the parasite that cause this infection. Schistosomiasis is found mostly in tropical climates around the world. These are a few of the areas where this infection is known to be endemic: Asia, Africa and South America (Wilson and Sande, 2001). Caribbean islands such as Martinique, Montserrat, Puerto Rico and St. Lucia have been known to carry a low risk for schistosomiasis (DHPE, 2005).
Centers for Disease Control & Prevention (CDC). (2008, February). Schistosomiasis: Fact Sheet. Retrieved April 3, 2009 from schistosomiasis/factsht_schistosomiasis.htm.
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from

5. Types of Schistosoma Schistosoma mansoni Schistosoma japonicum
Schistosoma japonicum
lifesciencedb.jp
Schistosoma haematobium
There are essentially three types of Schistosoma: Schistosoma mansoni, Schistosoma japonicum and Schistosoma haematobium. Schistosoma mansoni is usually found in Africa, the Middle East, South America and the Caribbean; whereas, S. japonicum is often found in rice paddies in the Far East (Hawley, 2000). Schistosoma haematobium infections are often isolated to Africa and the Middle East (Hawley, 2000).
These three parasitic agents can cause different clinical syndromes in humans. Intestinal schistosomias is the disease associated with infection from either S. mansoni or S. japonicum. On the other hand S. haematobium causes vesicular schistosomiasis (Johnson et. al., 2002). The most severe health issue associated with these parasites is Bladder carcinoma and the highest association with this health issue is in Egypt (Hawley, 2000). The host reservoirs for the parasite S. mansoni are rodents and certain primates. Cats, dogs, cattle and pigs are among the host reservoirs for the S. japonicum species (Johnson et. al., 2002). Primates are said to be the primary reservoir for the parasite S. haematobium.
All three species of this parasite are contracted through contact with contaminated water. There are two specific modes of progression for these parasites in the human body. The parasites enter into the blood circulation after entering the skin and once in the blood they mature into adults and then enter into the intra hepatic portal blood circulation (Johnson et. al, 2002). There is a nonhuman species of the parasite that causes dermatitis once breaking through the skin. The itching due to this dermatitis becomes severe after about 2 to 3 days upon being infected.
* Hawley, L. B. (2000). High Yield Microbiology and Infectious Diseases. Baltimore, MD and Philadelphia, PA: Lippincott, Williams and Wilkins.
* Johnson, A.G.; Ziegler, R.J.; Lukasewycz, O. A and Hawley, L. B. (2002). BRS: Microbiology and Immunology (4th Ed). Baltimore, MD and Philadelphia, PA: Lippincott, Williams and Wilkins.

6. Life Cycle
The blood fluke life cycle has several very specific steps that are related to the Schistosomiasis infection. The first step in the cycle of infection is contamination of freshwater with feces or urine that contain the parasites. Eggs are then hatched and they release particles which are referred to as ciliated motile miracidia (Wilson and Sande, 2001). The miracidia that are released in the water penetrate a certain type of snails that are used as the primary hosts. Once in the snails, the parasites are called sporocysts. The sporocysts grow and reproduce inside of the snail, but once they are released the parasites name changes again. The free swimming phase is known as cercariae. This is when the parasites go through the skin, enter the bloodstream, and then mature in the intrahepatic portal circulation. During the cercariae the parasites are released into the water, where they can survive for around 48 hours (DHPE, 2005). Penetration of the skin occurs when individuals come into contact with contaminated water sources. During the penetration process the cercariae lose their tails and become schistosomulae (DHPE, 2005). Once the penetration process is completed the parasites enter into the circulation. The next step for the parasites is to migrate to the liver where they mature into adults. The adults then pair up and travel to the rectum or the bowel. When the adult parasites lay eggs, some of the eggs continue to circulate while others are shed in the stool (DHPE, 2005). Those that continue to circulate ultimately inhabit the small veins of the intestine or the bladder. The two forms that usually inhabit the intestines are S. mansoni and S. japonicum (Hawley, 2000). Schistosoma haematobim has the potential to be the most fatal because it invades the liver (Hawley, 2000).
Schistosomiasis_Life_Cycle.jpg
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from
* Hawley, L. B. (2000). High Yield Microbiology and Infectious Diseases. Baltimore, MD and Philadelphia, PA: Lippincott, Williams and Wilkins.
* Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill

7. Disease Syndromes Swimmer’s Itch (Dermatitis) Katayama Fever
Chronic Fibro – Obstructive Disease
Bladder Carcinoma
schistosomiasis1.jpg
The four disease syndromes associated with schistosomiasis infections are Dermatitis, Katayama Fever, Chronic Fibro-Obstruction Schistosomiasis and Bladder carcinoma (Wilson and Sande, 2001). Dermatitis or swimmer’s itch is the least severe of these conditions; while, bladder cancer is the most severe. Infections with these parasites can affect the organs such as the skin, the intestines, the liver and of course the bladder (Kumar, Abbas and Fausto; 2007).
path.upmc.edu
roboticoncology.com
* Kumar, V; Abbas, A. and Fausto, N. (Eds.).(2007). Robbins and Cotran: Pathologic Basis of Disease. Philadelphia, PA: Elsevier Saunders.
* Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill.

8. Signs / Symptoms 4. Bladder Carcinoma 1. Dermatitis 2. Katayama Fever
Itchy
Papular Rash
2. Katayama Fever
Fever
Chills
Headache
Cough
Lymphadenopathy
Hepatosplenomegaly
3. Chronic Fibro-Obstruc.
Chronic Granulomatous Disease
Fibrosis
4. Bladder Carcinoma
Painless Hematuria
Frequency
Urgency
Dysuria
Swimmer’s Itch or dermatitis is the first condition that can result from this particular parasite. Dermatitis which is an acute form of schistosomiasis, usually occurs 1 to 3 days after the parasites penetrate the skin (Wilson and Sande, 2001). The signs of swimmer’s itch are a pruritic, popular rash.
The next condition is Katayama Fever. Some of the symptoms of this health issue are fever, chills, headache and cough. Lymphadenopathy and hepatosplenomegaly are two of the hallmark signs associated with Katayaman Fever (Wilson and Sande, 2001). Katayama Fever occurs somewhere between 4 – 8 weeks after penetration of the parasite.
The third health concern is Chronic Fibro-Obstruction Schistosomiasis. Chronic Granulomatous Disease and fibrosis are what results from the chronic inflammatory response due to the deposition of eggs. The symptoms of schistosomiasis result from the deposit of a number of eggs and not from the fluke worms themselves (DHPE, 2005).
The final and most severe health issue is Bladder carcinoma. Egypt and Sudan are the areas of the world where S. haematobium are most likely to contract bladder cancer due to infections caused by this parasite (Kumar, Abbas and Fausto; 2007). The classic signs of this type of cancer are frequency, urgency and dysuria. Painless hematuria is the ultimate sign that arises during this condition’s clinical course (Kumar, Abbas and Fausto; 2007). This is a severe form of cancer because even though these tumors can be excised they have the ability to reoccur as a higher grade cancer (Kumar, Abbas and Fausto; 2007).
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from
* Kumar, V; Abbas, A. and Fausto, N. (Eds.).(2007). Robbins and Cotran: Pathologic Basis of Disease. Philadelphia, PA: Elsevier Saunders.
* Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill.

9. Laboratory Findings Parasite Eggs in Feces / Urine Eosinophilia
Hematuria
Anemia
Abnormal LFT’s
Increased Creatinine
Uremia
There are several laboratory tests that can be used to confirm a diagnosis of schistasomiasis. The gold standard in diagnosis is finding parasite eggs in feces or urine. Some of the patho-physiologic signs of the infection are eosinophilia, hematuria, anemia and uremia (Wilson and Sande, 2001). The parasites work their way to liver and the interaction with the liver results in abnormal liver function tests and in increase in serum creatinine (Wilson and Sande, 2001).
(Wilson and Sande, 2001 p )
Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill.

10. Global Impact ??? Increase Incidence / Prevalence
Increase Morbidity / Mortality
Increase in Use of Public Health Resources
Schistosomiasis is known to be endemic in over 74 developing countries. An estimates 600 million people are at risk of becoming infected with this parasite (Micro, 2007). Public health professionals think that 200 million people are already infected with schistosomiasis. These parasites usually affect adult workers in rural areas, who are employed either in agriculture or the freshwater fishing sector (Micro, 2007). Infection occurs in a high proportion of children between the ages of 10 and 14 in many of the areas that house this parasite (Micro, 2007). It is estimated that about 200,000 people will die in Sub – Saharan Africa due to infections with schistosomiasis (WHO, 2009).
Urinary schistosomiasis affects millions of people all over the world. It is estimated that 66 million children throughout 54 countries may experience urinary schistosomiasis (Mirco, 2007). For example, there is a lake that surrounds a village in Ghana that is greatly infested with schistosoma parasites. In this village over 90% of the children are infected with schistosomiasis (Micro, 2007).
According to the Directors of Health Promotion & Education, schistosomiasis is considered to be an emerging infectious disease (DHPE, 2005). As an emerging infectious disease it will take more public health resources to contain these parasitic infections. It will benefit the public health industry to intervene when these infections are minor instead of waiting for the infections to become more serious. Once the schistosomiasis conditions become cancerous this will ultimately cost the medical industry more resources as well as money to treat these individuals.
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from org/infect/schisto.html.
* MicrobiologyBytes (Micro). (2007, January). Schistosomiasis. Retrieved May 1, 2009 from

11. Epidemiological Data Effects about 500,000 in the U.S.
Occurs in > 200 million worldwide
Schistasoma infections affect more than 200 million people worldwide every year. While it is true that the parasites that cause schistasomiasis are not endemic to the United States these infections still affect many Americans. Public health professionals estimate that these parasites infect about 500,000 people in the United States annually. The cases in the U.S. are mostly do to travel outside the country.

12. S. mansoni: : Estimated Morbidity and Mortality
At risk of infection 393      
Infected 54
Diarrhoea during previous 2 weeks 0.78 ( )
Blood in stool during previous 2 weeks 4.4 ( )
Hepatomegaly (mid-sternal line) 8.5
Splenomegaly [6.3]
Ascites [0.29]
Haematemesis (ever) [0.93]
Haematemesis (deaths/year) [0.13]
These are the current estimations of morbidity and mortality for S. mansoni in Sub – Saharan Africa.
* World Health Organization (WHO). (2009). Schistosomiasis: Epidemiology. Retrieved May 1, 2009 from int/schistosomiasis/ epidemiology/ table/ en/ index.html

13. S. haematobium: Estimated Morbidity and Mortality
At risk of infection 436      
Infected 112
Haematuria during previous 2 weeks 71 (52-89)
Dysuria during previous 2 weeks 32 (17-55)
Minor bladder morbidity (detected by ultrasound) 76 (67-92)
Major bladder morbidity (detected by ultrasound) 24 (15-31)
Moderate hydronephrosis 9.6
Major hydronephrosis 9.6
Non-functioning kidney [1.7]
Non-functioning kidney (deaths/year) [0.15]
Bladder cancer (deaths/year) Males [0.011]   Females [0.0023]
These are the current estimations of morbidity and mortality for S. haematobium in Sub – Saharan Africa.
* World Health Organization (WHO). (2009). Schistosomiasis: Epidemiology. Retrieved May 1, 2009 from int/schistosomiasis/ epidemiology/ table/ en/ index.html

14. What’s Being Done Now Prevention Methods Treatments
Environmental Regulations
There are many precautions that can be followed in order to prevent contracting schistosomiasis. The most important thing that can be done is to avoid swimming or wading in fresh water in countries where schistosomiasis occurs (DHPE, 2005). Drinking safe water is another way to prevent infection with these parasites. This is easier said than done when many of the countries affected by this issue may not have access to safe water. One way to make water safer is to boil the water for at least 1 minute to kill any organisms present in it (DHPE, 2005). Another way to make the drinking water safer is to treat the water with iodine, but this treatment alone will cannot guarantee water safety (DHPE, 2005). There are other prevention measures that can be taken and these can be found on the CDC website.
The drug of choice for treating infections due to schistosomiasis is praziquantel. This is an antiparasitic drug that works by paralyzing the parasites muscles and then it kills the parasite (Trevor, Katzung and Masters, 2005). While this is an ideal medication for the treatment of schistosomiasis there are some side effects associated with its use. Some of the side effects are headache, dizziness, malaise and gastrointestinal irritation (Trevor, Katzung and Masters, 2005).
The Panel of Experts for Environmental Management (PEEM) was established in 1979 to better introduce and develop the environmental management resources in the context of vector and disease control (Madramootoo, Johnston and Willardson, 1997). This panel of experts was composed of the World Health Organization, the Food and Agricultural Organization and the United Nations Environmental Program in an attempt to manage the issues in the environment. Most of the environmental regulations that exist concerning schistosomiasis are associated with the development and up-keep of water systems. Water development projects, such as those associated with irrigation have been associated with an increased incidence of schistosomiasis (Madramootoo, Johnston and Willardson, 1997). The construction of new water ways and dams has introduced the schistosoma parasites into countries that had not previously been affected by these infections.
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from org/infect/schisto.html.
* Madramootoo, C. A.; Johnston, W. R. and Willardson, L.S. (Ed.) (1997). Management of Agricultural Drainage Water Quality. Rome: Food and Agricultural Organization (FAO).
*Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill
* Trevor, A. J.; Katzung, B. G. and Masters, S. B. (Ed. 7th). (2005). Pharmacology: Examination and Board Review. New York: Lange Medical Books / McGraw-Hill.

15. What Needs to Be Done Increase Public Education / Awareness
Better Water Treatment
More Collaborative Efforts
The number one obstacle that faces parasitic diseases is educating the public about them. Not enough of the public are aware of the existence of these disorders and I feel that communication is the key to education. The fact that parasitic infections affect millions of people worldwide is the reason that it is important that the public be educated about these organisms and become aware of the health conditions associated with them.
Building and developing new agricultural and water resources around the world is another way the parasites are spreading. These new developments are increasing the number of people that are exposed to these types of infections. One source attributes the increase in incidence to a “refugee movement in Africa, the Eastern Mediterranean, and Asia, and construction of dams, reservoirs, and irrigation systems are introducing schistosomiasis to new areas and increasing the spread of infection” (DHPE, 2005). The continued spreading of these parasites is evidence that better water facilities and treatment methods need to be found.
While there are some collaborative efforts, such as the Panel of Experts for Environmental Management (PEEM), more needs to be done. For instance; another obstacle that this group of infections faces is a lack of government funding. The government responds to the will of the public and unless the public is more informed about these infections and resulting health problems the government will not invest as much into programs for them.
* Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from org/infect/schisto.html.

16. Bibliography For more information on Schistosomiasis
refer to the following resources:
Centers for Disease Control and Prevention: Division of Parasitic Diseases (
Directors of Health Promotion and Education (
Global Health Council (
U.S. National Library of Medicine and the National Institutes of Health: Medline Plus (
World Health Organization (

17. References
Centers for Disease Control & Prevention (CDC). (2008, February). Schistosomiasis: Fact Sheet. Retrieved April 3, 2009 from schistosomiasis/ factsht_schistosomiasis.htm.
Directors of Health Promotion & Education. (2005). Schistosomiasis. Retrieved April 5, 2009 from org/infect/schisto.html.
Hawley, L. B. (2000). High Yield Microbiology and Infectious Diseases. Baltimore, MD and Philadelphia, PA: Lippincott, Williams and Wilkins.
Johnson, A.G.; Ziegler, R.J.; Lukasewycz, O. A and Hawley, L. B. (2002). BRS: Microbiology and Immunology (4th Ed). Baltimore, MD and Philadelphia, PA: Lippincott, Williams and Wilkins.
Kumar, V; Abbas, A. and Fausto, N. (Eds.).(2007). Robbins and Cotran: Pathologic Basis of Disease. Philadelphia, PA: Elsevier Saunders.
MicrobiologyBytes (Micro). (2007, January). Schistosomiasis. Retrieved May 1, 2009 from

18. References Cont.
Moeller, D. W. (2005). Environmental Health (3rd ed.). Boston: Harvard University Press.
Madramootoo, C. A.; Johnston, W. R. and Willardson, L.S. (Ed.) (1997). Management of Agricultural Drainage Water Quality. Rome: Food and Agricultural Organization (FAO).
Trevor, A. J.; Katzung, B. G. and Masters, S. B. (Ed. 7th). (2005). Pharmacology: Examination and Board Review. New York: Lange Medical Books / McGraw-Hill.
Wilson, W. R. and Sande, M. A. (2001). Current Diagnosis & Treatment in Infectious Diseases. United States: McGraw-Hill.
World Health Organization (WHO). (2009). Schistosomiasis: Epidemiology. Retrieved May 1, 2009 from int/schistosomiasis/epidemiology/table/en/index.html