Burden of diarrheal diseases from biogas wastewater exposure among smallholder farmers in Ha Nam province, Vietnam

Burden of Diarrheal Diseases from Biogas Wastewater Exposure

Among Smallholder Farmers in Ha Nam Province, Vietnam Phuc Pham-Duc; Toan Luu-Quoc; Huong Nguyen-Mai; Tuyet-Hanh Tran Thi; Tung Dinh-Xuan; Hang Tran-Minh;

Hung Nguyen-Viet

Center for Public Health & Ecosystem Research, Hanoi University of Public Health; National Institute of Animal Scienc-

es; Institute of Anthropology; Vietnam Academy of Social Sciences; International Livestock Research Institute

INTRODUCTION

Livestock production has developed rapidly in Vietnam in recent years, particu-

larly at the small-scale which account for 65% of the total livestock production.

Biogas systems are commonly used to treat livestock waste, however, the

health risks from biogas wastewater exposure at smallholder farms are not yet

well understood. Objective was applied transdisciplinary and community par-

ticipatory approach (called Ecohealth approach) to assess the health risks as-

sociated with biogas wastewater; and improve knowledge and practice of

farmer for better operation of biogas systems and treatment of waste.

Contact: Phuc Pham-Duc

Email: [email protected] ; [email protected]

Mobile: (+84) 904049969. Web: www.vohun.org

METHODS

Research Process

A quantitative microbial risk assessment approach was applied to estimate the

burden of diarrheal diseases from biogas wastewater exposure among 451

smallholder farmers using biogas systems in Ha Nam province. A total of 150

biogas wastewater samples were collected and analysed for E. coli, Giardia,

and Cryptosporidium.

CONCLUSION The results suggest the importance in reducing concentrations of pathogens

in biogas wastewater before use in the fields as a means for mitigating pub-

lic health impacts.

The study showed that farmers faced diarrheal disease risks due to expo-

sure to biogas wastewater at different exposure scenarios. The calculated

annual risk of diarrheal disease by E. coli ranked from 0.15 to 0.21; by Giar-

dia ranked from 0.022 to 0.095; and by Cryptosporidium ranked from 0.006

to 0.015. The estimated diarrheal diseases burden from pathogens in all ex-

posure scenarios largely exceeded the reference level of health outcome

target of 10-6 DALYs loss per person per year recommended by WHO.

RESULTS

ACKNOWLEDGEMENTS

This study was supported by the Canadian International Development Research

Center (IDRC) through the project of Ecohealth Field Building Leadership Initiative

(FBLI) in Southeast Asia.

This poster presentation and travel award are made possible by the generous sup-

port of the American people through the United States Agency for International

Development (USAID). The contents are the responsibility of the presenters and

do not necessarily reflect the views of USAID or the United States Government.

Current status of agriculture & environment in Ha Nam

Pathogens in biogas wastewater at the small-holder farms

Figure 1: The burden of diarrhoeal from pathogens in all the expo-

sure scenarios

Pathogens Positive Mean ± SD QCVN 62-

MT:2016/

BTNMT n %

E. coli (*)

(CFU/ml) 75 100 14,665 ± 34,854 5,000

Giardia(**)

(cysts/ml) 33 44.0 9.4 ± 23.0 -

Cryptosporidium(**)

(cysts/ml)

26 34.7 9.2 ± 25.7 -