Folic-acid-preventable spina bifida and anencephaly.

Annex A FACT SHEETS FOR CANDIDATE DISEASES FOR ELIMINATION OR ERADICATION 1. Noninfectious conditions Folic-acid-preventable spina bifida and anencephaly* 1. Brief description of the condition/disease Spina bifida and anencephaly are among the most common and severe birth defects. Almost all af- fected persons wsith spina bifida liave lower-body paralysis anid significant physical disability. In many countries, spina bifida is thc most common cause of infantile paralysis. Anencephaly is a common birth defect that contributes to fetal and infant mortality. An estimated 50-75% of these birth defects can be prevented by providing adequate intakes ot synthetic tolic acid (pteroylmonoglutamic acid) before and during the first trinester of pregnancy. Prcvcnting folic-acid-preventable spina bifida and anencephaly presents an outstanding opportunity to improve the health of children throughout the world. Moreover, substantial evidence suggests that, in adults, suboptimal intakc of folic acid is a major factor for increasing the risk ot cardiovascular disease. 2. Current burden and rating within the overall burden of disease Each year. 300000 to 400000 mfants worldwide are born with spina bifida and anencephalv. In China. 100(X)0 infants arc born annually with these two birth defects, which are the leading cause of infant mortality. The rates are also high in Mexico and Central America. Together these conditions contrib- ute significantly to infant morbidity and mortality. 3. Feasibility (biological) of elimination/eradication Approximately 75% of spina bifida and anencephaly are folic-acid-preventable. and it is biologically possible to prevent all tolic-acid-preventable spina Contributed by Godfrey P Oakley. Jr, Centers for Disease Control and Prevention, Atlanta, GA, USA. bifida and anencephaly. The prevention Impact would be approximately equal to the prevention derived fromu poliomyelitis vaccines. The biological feasibilitv of preventing spina bifida and anencephaly using folic acid-containing vitanmin supplcments has been demonstrated in randomized controlled trials and otber studLes. Data from tlhese studies indicate a 50-100% reduction in nsk for women taking the supplement beforc con- ception and during the first trimester of pregnancy. No randomized controlled studies indicate that diet- ary changes alone will prevent these birLh defecLs. The U.S. Public Health Service recommends that all women who couJd become pregnant should consume 400(i)g of folic acid daily to pi event these birTlh defects. Many other countries have policy statenments secking to increase consumption. The Uniited States Institute of Medicine recommcnded in Apnl 1998 that all women who could become preg- nant should consume 400ilg daily of synithetic folic acid to prcvent birth defects. 4. Estimated costs and benefits of elimination/eradication Folic acid fortification of flour is feasible and inex- pensive In the USA, formal analysis of costs and benefits of fortification of wheat flour and other grains inidicate that a fortification strategy would be highly cost-beneficial. Because costs associated vith the purchase and distribution of Colic-acid- containing supplements would be higher, pro- grammes depending on pill consumption would break even. 5. Key strategies to accomplish the objectives Folic acid intake to prevent folic-acid-preventable spina bifida and anencephaly can be increased by tortifying staple foods with folic acid or implement- ing a programme that increases the consumption of 116 Bulletn of the World Health Organization 1998, 76 (SuppI 2) 116-117 Folic-acid-preventable spina bifida and anencephaly tolic-acid-conlaining supplements. as follows: fortity with synthetic tolic acid one or more centrally processed and distributed foods, such as gram prod- ucts, so that tlc vast malonty of reproductive-aged women consume at least 40O0tg ot folic acid each day: establish folic acid '4itammi] pill consumption programmnes; add folic acid to iron supplement pill programs; and add folic acid to contraceptive pills. 6. Research needs Cost-effective methods for populationi assessmnent of blood folatc levels need to be field tested and in- proved. Such indicators of folate status are needed to provide a iediable means of cvaluatin2 tlle cffectivc- ness of folic acid intcrvention programmes. Research is needed to develop messages that will motivate women to consume more folic acid. 7. Status of elimination/eradication efforts to date Although many countiles havc developed tecom- mendations to mcrease the consumption of folic acid, more needs to be done to implement these strategies. In the USA. 3 of 4 reproductive-aged women have blood folate levels that place them at risk of having a child with a folic-acid-preventable birth defect. Data from Europe are similta. The USA and China are implementincg programmes to increase folic acid intakes. Approximately 20 other countries encourage the use ot folic-acid-contamiing vitamins and the consumption of folatc-rich foods The USA and a few' other counltries have fortified one or more grain products wvith tolic acid. Fortifica- tion concentration levels, however, so far have not been sufficient for complete prevenition of these pre- ventable birth detects. 8. Principal challenges to elimination/eradication The principal challenges to eliminating folic-acid- preventable birth defects are a lack of awareness of this preventioni opportuniLy by health care providers. policy-makers, and the public; the financial burden and logistical barriers to providing supplements to women; lack of centrally processed and distributed foods to serve as fortificatioln vehicles in some coun- tries; rcoulations in some countries limiting the amount of tolic acid in supplement pills. misinLerpre- tation of data, rcsulting in recomnmendation to promote only increased consuimption of folate-rich foods rather than an adequate fortification or sup- plemeiit programme with crystalline folic acid (pteroylmonoglutamic acid): and unwillingness of government to set fortification concentration levels high enough. WHO Bulletin OMS Vol 76, Suppl 2 1996 117