Decline in the prevalence of neural tube defects following folic acid fortification and its cost-benefit in South Africa.
BACKGROUND
In October 2003 South Africa embarked on a program of folic acid fortification of staple foods. We measured the change in prevalence of NTDs before and after fortification and assessed the cost benefit of this primary health care intervention.


METHODS
Since the beginning of 2002 an ecological study was conducted among 12 public hospitals in four provinces of South Africa. NTDs as well as other birth defect rates were reported before and after fortification. Mortality data were also collected from two independent sources.


RESULTS
This study shows a significant decline in the prevalence of NTDs following folic acid fortification in South Africa. A decline of 30.5% was observed, from 1.41 to 0.98 per 1,000 births (RR = 0.69; 95% CI: 0.49-0.98; p = .0379). The cost benefit ratio in averting NTDs was 46 to 1. Spina bifida showed a significant decline of 41.6% compared to 10.9% for anencephaly. Additionally, oro-facial clefts showed no significant decline (5.7%). An independent perinatal mortality surveillance system also shows a significant decline (65.9%) in NTD perinatal deaths, and in NTD infant mortality (38.8%).


CONCLUSIONS
The decrease in NTD rates postfortification is consistent with decreases observed in other countries that have fortified their food supplies. This is the first time this has been observed in a predominantly African population. The economic benefit flowing from the prevention of NTDs greatly exceeds the costs of implementing folic acid fortification.
Sayed
Abdul-Rauf
AR
School of Public Health and Family Medicine, University of Cape Town, South Africa.
Bourne
David
D
Pattinson
Robert
R
Nixon
Jo
J
Henderson
Bertram
B
D000013:Congenital Abnormalities / Q000453:epidemiology; D003362:Cost-Benefit Analysis; D019587:Dietary Supplements; D005492:Folic Acid / Q000191:economics* / Q000627:therapeutic use*; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D015997:Neonatal Screening; D009436:Neural Tube Defects / Q000191:economics / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control*; D015995:Prevalence; D018571:Sentinel Surveillance; D013019:South Africa / Q000453:epidemiology
D005492:Folic Acid