Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Controlling schistosomiasis: buffalo or snails?

Controlling schistosomiasis: buffalo or snails?

January 22, 2008

A parasitic infection common in China and Southeast Asia could be effectively reduced by controlling snail populations, according to research published in PLoS Medicine.

Infection with schistosomes of various species affects some 200 million people worldwide, and can cause serious chronic illnesses, including liver failure. Steven Riley of the University of Hong Kong and collaborators analyzed infection patterns of the parasitic worm Schistosoma japonicum in fifty villages in Samar Province, the Philippines. Rates of infection among humans and animals have been found to differ among villages, and the researchers developed a mathematical model incorporating fecal parasite test results from thousands of people and animals (including, cats, pigs, dogs, water buffalo, and rats) to explain these differences.




Schistosomes are passed from mammals to fresh-water snails via feces, and then cycle back to infect mammals that contact water inhabited by infected snails. Using the mathematical model, the team found that transmission from snails to mammals was a more important factor in explaining the differences among villages than transmission from mammals to snails.

As with all scientific models, the findings of this one depend on the assumptions made to build the model. Nevertheless, the findings suggest that interventions to reduce the size of the snail population and the exposure of mammals to parasite-containing water might reduce human infection levels more effectively than interventions that interrupt other parts of the parasite's life cycle.

The results also indicate that the contribution of water buffaloes to human S. japonicum infection in the Philippines is not particularly important. This finding contrasts with a recent study that identified water buffalo as the major mammalian reservoir for S. japonicum in China. (http://www.who.int/bulletin/volumes/85/7/06-034033/en/index.html), and suggests that further studies of t he transmission of S. japonicum by water buffalo are warranted before efforts are dedicated to treat or vaccinate water buffalo as a control measure against human S. japonicum infection.

In a related perspective article, Song Liang and Robert Spear, who were not involved in the study, discuss the findings and conclude that the "modeling approach can be a useful tool in exploring schistosomiasis transmission in other settings, and may even apply to other macroparasites."

http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0050018

Public Library of Science



Related Schistosomiasis Current Events and Schistosomiasis News Articles Schistosomiasis Current Events and Schistosomiasis News RSS Schistosomiasis Current Events and Schistosomiasis News RSS
What are coral reef services worth? $130,000 to $1.2 million per hectare, per year: experts
Experts concluding the global DIVERSITAS biodiversity conference today in Cape Town described preliminary research revealing jaw-dropping dollar values of the "ecosystem services" of biomes like forests and coral reefs - including food, pollution treatment and climate regulation.

Discovery to aid in future treatments of third-world parasites
Schistosomiasis, one of the most important of the neglected tropical diseases, is caused by infection with parasitic helminths of the genus Schistosoma.

Scientists decode genome of deadly parasitic worm
Scientists have sequenced the genome of the parasite that causes intestinal schistosomiasis (also known as bilharzia or snail fever), a devastating tropical disease that afflicts more than 200 million people in the developing world.

U of M study finds new insight on therapy for a devastating parasitic disease
University of Minnesota Medical School researchers have discovered an important new insight into how a commonly prescribed drug may work to treat those infected by a parasitic flatworm.

Case Western Reserve professor helps control infectious diseases with models and math
Can an algebraic equation hold the secret to eradicating malaria or schistosomiasis? A Case Western Reserve University mathematics professor is utilizing the combination of algorithms and models in an effort to assist his medical colleagues in the fight against infectious diseases.

Snails and humans use same genes to tell right from left
Biologists have tracked down genes that control the handedness of snail shells, and they turn out to be similar to the genes used by humans to set up the left and right sides of the body.

Are bone marrow mononuclear cells effective in reducing hepatic lesions?
Liver fibrosis occurs in the setting of chronic injury caused by different etiologies constituting a serious worldwide public health problem. In addition to schistosomiasis, hepatopathies due to alcohol, viral hepatitis, drugs, metabolic and autoimmune diseases, and congenital abnormalities are important causes of liver fibrosis.

Parasitic worm infections increase susceptibility to AIDS viruses
Persons infected with schistosomes, and possibly other parasitic worm infections, may be more likely to become infected with HIV than persons without worm infections, according to a study published July 23rd in the open-access journal PLoS Neglected Tropical Diseases.

Fuzzy logic water quality
A fuzzy logic approach to analyzing water quality could help reduce the number of people in the developing world forced to drink polluted and diseased water for survival.

Tropical disease experts call for a 'Global Fund to Fight Neglected Tropical Diseases'
An international team of tropical disease control experts has urged the global health and development community, and particularly the G8 leaders, to establish a new financing mechanism to combat the neglected tropical diseases (NTDs) of poverty.
More Schistosomiasis Current Events and Schistosomiasis News Articles
Schistosomiasis (World Class Parasites)

Schistosomiasis (World Class Parasites)
by W. Evan Secor (Editor), Daniel G. Colley (Editor)

This book provides insights into the research and programs currently related to schistosomiasis, and uses these insights to project into future years of work on schistosomiasis, from research to public health interventions. A secondary goal is to initiate conversations among those working on schistosomiasis about the future of their field, and by doing so lead to constructive efforts to identify and address the most critical questions and challenges related to schistosomiasis. The first 4 chapters address schistosome phylogenetics, gene expression, and the overall genome. The next 3 chapters explore the host-schistosome interaction at the larval to adult worm interface. The following 3 chapters explore the development of the host immune response to eggs, granuloma formation and factors...

Schistosomiasis

Schistosomiasis
by Adel A. F. Mahmoud (Editor)

The author is president of Merck Vaccines, Merck & Co., Inc. Updates fundamental clinical knowledge of schistosomes, with coverage of their biology and epidemiology, clinical syndromes and pathological sequelae in humans, aspects of diagnosis and treatment, and vaccine development.

  A Study of Intensive Antimony-Therapy in Schistosomiasis Japonica; The Route of Migration of Schistosoma Japonicum in the Body of its Final Host. Offprints, Journal of Tropical Medicine and Hygiene, Proc. Soc. Experimental Biology and Medicine.
by Ernest Faust (Author)



  Snail Hosts of Schistosomiasis and Other Snail-Transmitted Diseases in Tropical America: A Manual (Scientific Publication, No 478)
by Emile Abdel Malek (Author)



  Human Schistosomiasis
by Jordan. Peter and Webbe. Gerald (Author)



Prevention and Control of Schistosomiasis and Soil-transmitted Helminthiasis: Report of a WHO Expert Committee (WHO Technical Report Series)

Prevention and Control of Schistosomiasis and Soil-transmitted Helminthiasis: Report of a WHO Expert Committee (WHO Technical Report Series)
by World Health Organization (Author)

This report contains the recommendations of a WHO Expert Committee convened to consider the prevention and control of schistosomiasis and soil-transmitted helminth infections. Although these infections remain major public health concerns in many parts of the world, particularly in the poorest developing countries, cost-effective solutions are both available and deliverable.

The report reviews the burden of disease, its impact on both health and development, the substantial benefits of treatment, and the safety, efficacy and ease of administration of available anthelminthic drugs. Similarities in the populations at risk and in the tools required to combat the problems have prompted moves towards a combined approach to the control of schistosomiasis and soil-transmitted ...

  Immunoparasitology: Principles and Methods in Malaria and Schistosomiasis Research
by G. Thomas Strickland (Editor), Kenneth W. Hunter (Editor)



Schistosomiasis Medical Guide

Schistosomiasis Medical Guide
by Qontro Medical Guides (Author)

The Schistosomiasis Medical Guide is a publication which has been designed to better help readers understand Schistosomiasis. This Qontro Medical Guide has been designed with the reader in mind, and is a useful information source for readers at all levels looking to learn more about Schistosomiasis. The Schistosomiasis Medical Guide is highly recommended for those interested in understanding and learning more about Schistosomiasis.

  Schistosomiasis in Twentieth Century Africa: Historical Studies on West Africa & Sudan. K
by David Patterson (Author)



  Human Schistosomiasis (Cabi Publishing)
by P. Jordan (Editor), G. Webbe (Editor), R. F. Sturrock (Editor)

Human schistosomes (blood flukes) are diagnostic trematodes that spend the adult part of their life cycle in humans and a further part in aquatic snails. Despite advances in chemotherapy, schistosomiasis is still a significant infection in the populations of numerous countries in the tropics.

This book replaces a previous volume - Schistosomiasis: Epidemiology, Treatment and Control (Heinemann, 1982) - by Jordan and Webbe. All chapters have been rewritten by internationally renowned workers. Ultrasound (which is expected to aid identification of early disease in the field and increase our understanding of its evolution) is discussed in a new chapter. Other chapters, each with an extensive bibliography, review the parasites and their snail intermediate hosts, epidemiology, clinical...

© 2009 BrightSurf.com