Sustained effectiveness of weekly iron-folic acid supplementation and regular deworming over 6 years in women in rural Vietnam

Background: Weekly iron-folic acid (IFA) supplementation and regular deworming is effective for the prevention of iron deficiency and anaemia in women of child-bearing age. Between 2006 and 2013, a program of weekly IFA and biannual deworming was implemented in Yen Bai province, Vietnam. In this study we aimed to determine the effectiveness of the program in reducing anaemia and the prevalence of hookworm infection after 72 months (six years). Methods: This prospective cohort study followed up a cohort of 389 women of child-bearing age from baseline until six years after the introduction of the weekly IFA (one tablet containing 200 mg ferrous sulphate, 0.4mg folic acid) and deworming (one 400mg tablet of albendazole given twice yearly) program (May 2006 to 2012). In each of the six surveys (baseline and five follow-up surveys) we measured haemoglobin and ferritin, and the burden of soil transmitted helminth (STH) infections, and in the 72 month survey we also administered a questionnaire to assess adherence and possible impediments to participating in the program. Results: Two hundred and fifty six (65.8%) of the original 389 women enrolled in the cohort attended the final 72 month survey. Haemoglobin levels were 122 g/L [95% C.I. 120, 124] at baseline and increased to 135g/L [95% C.I. 133, 138] after 72 months. The prevalence of anaemia was 37.8% [95% C.I. 31.0, 44.7] at baseline and reduced to 14.3% [95% C.I. 9.5, 19.1]. Hookworm infection prevalence, 75.9% [95% C.I. 68.1, 83.8] at baseline, reduced to 10.2% [95% C.I. 5.4, 15.0] with no moderate or heavy intensity infections. Seventy-two percent of participants reported still taking at least 75% of the weekly supplements, and 85.0% had taken the most recent deworming treatment. Discussion: Anaemia rates fell significantly during the six-year program, and STH infections were eliminated as a public health risk. Adherence was well maintained but long-term sustainability is challenging in the absence of ongoing external support. Author summary: Weekly iron-folic acid (IFA) supplementation combined with regular deworming for women of child bearing age is effective in the prevention of iron deficiency and anaemia. Following a baseline survey, a weekly IFA and regular deworming project was implemented in Yen Bai province, Vietnam in 2006, and after 12 months expanded to the entire province. Haematological parameters, soil transmitted helminth (STH) burden and adherence to the program were monitored periodically until 2012. We found anaemia prevalence fell from 37.8% to 14.3% during the six-year period, and haemoglobin levels increased from 122 g/L to 135g/L. STH infections were essentially eliminated as a public health risk. Seventy-two percent of participants continued to take at least 75% of the weekly supplements, and 85.0% took the most recent deworming treatment. These results show that prevention of anaemia in women of child-bearing age with weekly IFA and regular deworming is feasible and effective over a prolonged period. However, long-term sustainability may be a major challenge in some settings in the absence of ongoing external support.