Reducing the Prevalence of Liverflukes through Food Safety Education
03 May 2011
"Through a geographical approach that also involves food health safety education, we can save more lives than medical intervention alone."
Dr Carl Grundy-Warr, NUS Department of Geography
RECONNAISSANCE FIELD TRIP, NOV 2008: (From left to right) Dr Sithithaworn, Dr Grundy-Warr, Dr Feng and Assoc Prof Andrews. Dr Sithithaworn was sharing with the group on the differences between Bithynia snails and other species
"Koi pla", "Pla som" and "Pla ra" are some of the staple foods made of raw or partially cooked freshwater fish, much loved by inhabitants of the Mekong River, including those living in northern Thailand. Yet such dishes are often contaminated with Opisthorchis viverrini, a trematode parasite that potentially leads to a fatal cancer of the bile duct.
Raising this alarming issue, Assoc Prof Alan Ziegler and Dr Carl Grundy-Warr of the Department of Geography, NUS; Assoc Prof Ross Andrews and Assoc Prof Paiboon Sithithaworn of the Department of Parasitology and Liverfluke and Cholangiocarcinoma Research Centre at the Faculty of Medicine of the Khon Kaen University, Thailand; and Dr Trevor Petney of the Department of Ecology and Parasitology of the University of Karlsruhe, Germany argued that the problem of liverflukes should be addressed with food safety education, in conjunction with medical and scientific approaches. Their research work was published in the January issue of the prestigious Science journal.
Today, more than 45 million people in Asia are infected with liverflukes. In Thailand and Laos, there are at least 10 million people infected. Regional estimates are not possible because censuses for Laos, Cambodia, and Vietnam are not accurate.
In the Science publication, the researchers highlighted how food safety education may be the most expedient way to control the disease, opistorchiasis, caused by Opisthorchis viverrini because its prevalence in humans is inherently linked to behaviour. Education proved to be successful in the past. "The way to reduce the incidence of cancer is to prevent liverfluke infection in the younger generations by educating children in school," noted Assoc Prof Paiboon Sithithaworn, who was attending an NUS Faculty of Arts & Social Sciences or FASS-sponsored workshop on Opisthorchis viverrini from 10-12 March 2011.
The challenge for the researchers in implementing food safety education will be in changing cultural perceptions of eating raw fish. Dr. Carl Grundy-Warr believes that "through a geographical approach that also involves food health safety education we can save more lives than medical intervention alone". Drs Ziegler and Grundy-Warr and three other NUS Faculty of Arts and Social Sciences, Dr Wang Yi-Chen, Dr Feng Chen-Chieh and Dr. Denise Kera are teaming with the international researchers to further understand not only the Opisthorchis viverrini species complex, but other water-borne diseases. "We are using Opisthorchis viverrini as a model organism to explore the multifaceted, multidisciplinary factors involved in water-borne diseases in general", stated Assoc Prof Andrews. According to Dr Petney, the linkage between diseases such as opisthorchiasis and the environment is inherent; and potential changes in land-use and climate are important phenomena that will likely affect the wetland environments where secondary hosts live.