in malnutrition

Lani S, Stephenson

The author discusses the significance of helminth and schistosomeinfections in exacerbating nutritional problems in many countries, andadvocates population-wide treatment where there is clear evidencethat this would yield substantial gains in the quality of life.

Infections with hookworm, roundwormand/ or whipworm are particularly significantif they cause or aggravate protein-energy mal-nutrition, iron-deficiency anaemia, vitamin-Adeficiency, or goiter (1). Some 500 millionchildren are affected by the first of these con-ditions, among whom about 10 million dieevery year; low weight and height for age orstunted growth occur in children aged twoyears and more. Irdn-deficiency anaemiaaffects 800-900 million persons. Helminthsand malnutrition usually occur in the samegeographical areas, and often in the same

persons.

increased maternal and fetal morbidity andmortality, premature delivery and lowbirth weight;reduced rate of cognitive development,poor pedormance at school, and increasedabsenteeism in schoolchildren;increased susceptibility to infection.

These factors in turn decrease the ability ofindividuals and families to grow food or earnsufficient money to buy it and other essen-tials. Although the extent to which hook-worm diminishes growth and the capacity towork is not known precisely; it seems clearthat hundreds of millions of people wouldbenefit significantly from treatment againstthis parasite.Hookl111'orm

The growth-stunting potential of hookwormhas long been known (2). Nutritional status isaltered through a decline in food intakeand/or an increase in nutrient wastagethrough blood loss, vomiting or diarrhoea.These effects can lead to or aggravate.protein-energy malnutrition, anaemia and other mani-festations of nutrient deficiency. The generalsocial and economic consequences include:

Roundworm

Roundworm infection or ascariasis is presentin up to 90% of children in some areas of thetropics. In 1987 there were probably overlOO 000 deaths caused by complications ofinfection with Ascaris lumbricoides, such asintestinal obstruction. This parasite also hasimportant nutritional effects; treatment canimprove food intake and growth in infectedchildren. The utilization of protein declinesin Ascaris-infected children, an importantphenomenon where there is severe protein-energy malnutrition or in children on low-protein diets. The absorption of fat decreases,

decreased work capacity and productivityin both children and adults;

Dr Stephenson is Associate Professor, Programin International Nutrition, Division of Nutritional SciencesCornell University, Ithaca, Savage Hall, New York14853-6301, USA.

169me 15 .1994World Health Forum .

Public Health Practice

Pathways whe,Icognitive abili,

likely to influence growth and physical andcognitive abilities. Worm infections appear todepress growth, physical fitness, physicalactivity and cognitive ability via twopathways, for both of which a central featureis depressed appetite (see figure). One mech-amsm involves iron-deficiency anaemia andthe poor appetite, poor growth and decreasedactivity that result from it. The other involvescytokines (endogenous factors) produced bythe body in response to parasitic infestation;they act directly on the brain, depress theappetite, increase the metabolic rate, decreaseactivity, and cause wasting and the break-down of fats and proteins.

and this may exacerbate protein-energymalnutrition and vitamin-A deficiency.Lactase activity in the small intestine isreduced, and lactose and milk intolerancedevelops in children.

Whipworm

Trichuriasis, or infection with the whipwonn(Trichuris trichiura), can cause prolapse of therectum and nutritional problems; the treat-ment of children can lead to increased haema-tocrit, improved growth rates andanthropometry, increased serum albumin,decreased diarrhoea, and a reduction in bacte-rial and protozoan infections in the gut.

Decreased appetite leads to a reduction infood intake, which in turn diminishes growthrate, physical fitness, physical activity andcognitive perfot:mance. Eventually, the adultpopulation shows decreased fitness and pro-ductivity, partly because of reduced body size.This chain of events is clearly undesirable,particularly in developing countries whereheavy manual labour frequently has to be

performed.

Schistosomiasis

Many of the nutritional effects of schistoso-miasis, caused by Schistosoma haematobium,S. mansoni and S. japonicum, are very likethose of the intestinal worms. U rinaryschistosomiasis causes blood loss in theurine of school-age children.

s. haematobialbendazole cand Ascaris ( lfor iron-defi(1989-90 boy:worms with ;with previou:indicated thalanaemia 1mplleast as muchschool feedinmuch more lc

expensive.

Societal significance

Children and adults feel better, are healthier,and can be more physically and mentallyactive and productive after treatment forhelminth infections and/ or anaemia (3-6).Recent studies in Kenya and elsewhere, com-

Recent studies in Kenya have demonstrated asignificant improvement in appetite accom-panying improved growth and fitness inschool-age children four months after a singletreatment against intestinal worm infections(4). In the prevention and control of malnutri-tion it is often just as important to improvethe desire of children to eat as it is to augmentthe ability of parents to produce or buy food.Clearly, people who consume too little foodcan only achieve energy balance and avoidbecoming severely undernourished bydecreasing their physical activity.

Countries at I

bined with precise holistic descriptions ofworm-infested persons in the earlier litera-ture, provide insights into the mechanisms bywhich helminth infections and anaemia are

In areas wherImoderate unc

where parasitshould be giv

Cost-effectiveness

In studies in Kenya during 1986, primaryschool children were treated with a single oraldos~ of metrifonate or praziquantel against

World Health Forum. Volume 15 .1994170 World Health FoflJm .

Dayamal R. L

In Sri LankaIdirected agG

treatment ral

grammes las I

children. Nutrition -an international journal, 1990,6:159-162.

7. Stephenson LSet al. Single-dose metrifonate orpraziquantel treatment in Kenyan children. II. Effectson growth in relation to S. haematobium and hook-worm egg counts. American journal of tropical medi-cine and hygiene, 1989,41: 453-461.

8. Stephenson LS et al. Treatment with a single doseof albendazole improves growth of Kenyan childrenwith hookworm, Trichuris trichiura and Ascarislumbricoides infections. American journal of tropicalmedicine and hygiene, 1989, 41: 78-87.

9. Latham MC, Robson JRK. A trial to evaluate thebenefit of different protein"rich foods to Africanschoolchildren. Nutritio et dieta, 1965, 7: 28-36.

10. Pieters JLL et al. Effects of school feeding ongrowth of children in Kirinyaga District, Kenya. EastAfrican medical journal, 1977, 54: 621-630.

11. Tomkins A, Watson, F. Malnutrition and infection: areview. Geneva, ACC/SCN, 1989 (State-of-the-ArtSeries, Nutrition Policy Discussion Paper No.5).

12. Grant JP. The state of the worlds children 1992. NewYork, Oxford University Press (for UNICEF), 1992.

Referem~es

1 Stephenson LS. Impact of h~lminth infections onhurrlan nutrition: schistosomes and soil-transmittedhelminths. New York, Taylor and Francis, 1987.

2. Rose W. The Rockefeller Foundation InternationalHealth Board Sixth Annual Report. New York, 1920.

3. -Crompton DWT, Stephenson LS. Hookworm infec-tion, nutritional status, and productivity. In: Schad GA,Warren KM, eds. Hookworm disease: current statusand new directions. London, Taylor and Francis,1990: 231-264.

4 Stephenson LS et al. Physical fitness, growth andappetite of Kenyan schoolboys with hookworm, Tri-churis trichiura and Ascaris lumbricoides infectionsare j!mproved four months after a single dose ofalbendazole. Journal of nutrition, 1993,123: 1036-1046.

5. Stephenson LS. The impact of schistosomiases onhuman nutrition. In: Crompton DWT, ed. Human nutri-tion fgnd parasitic infection. (Special issue of Parasi-

tolo!J7y) (in press).

6. LatHam MC et al. Improvements in growth followingiron supplementation in young Kenyan school-

Leprosy need not mean deformity

Most leprosy patients do not have disabilities or deformities when thedisease .first appears, and develop them later: Even when patientsdevelop disabilities and deformities, they are mild and reversible tobegin with and become severe and permanent only later on. Indeed,many conditions leading to disability and deformity can be cured ifaction is taken at an early stage, and the development of disabilities anddeformities can be prevented. ...Disability prevention requires activecollaboration between health care personnel on the one hand andpatients and their families on the other:

Although allLanka have 1:therapy sincedisease has C(

In 1990 a soclZatlOn camptackle this prfacilities to Slexpanding thdemand for tan awarenes~and reducingnational adv(which advel1ters, stickerssion serials awas highly p

regular :eviegroups.m Oftcorrective mnecessary. Lwere distrib\new patientscover very rlby the mass