~-

Intestinal Parasitic Infestations Among Children in anOrphanagein Pathum Thani Province

WILAI SAKSIRISAMPANT, MSc*,VIROJ WIWANITKIT, MD**,ANCHALEE AMPAVASIRI, BA***

SURANG NUCHPRA YOON, MD, PhD*,SUTIN YENTHAKAM, BSc*,

Abstract

Infection caused by intestinal parasites is still a common heaith problem especially in childrenfrom developing countries. Orphans are a group of underprivileged population in society. To evaluatethe intestinal parasitic infections in children in an orphanage in Pathum Thani province, Thailand, stoolsamples were collected during a cross-sectional study in April 2001. Examination for intestinal para-sites were performed by using simple smear. formalin-ether concentration, Boeck and Drbohlav'sLocke-Egg-Serum (LES) medium culture and special staining (modified acid-fast and modifiedtrichrome) techniques. A total Qf 106 pre-school orphans (60 males and 46 females), aged 10.0-82.0months, were recruited for the study. There were 86 individuals (81.1%), 45 males and 41 females,infected with at least one papsite. Interestingly. most of the parasites identified were protozoa. Blasto-cystis homillis was found at the highest prevalence (45.2%). The infections caused by Giardia lambliawas 37.7 per cent and Entamoeba histolytica was 3.7 per cent. Other non-pathogenic protozoa foundwere Trichomullas hontinis (39.6%), Entamoebl1 coli (lS.8c;iJ).ar.d t;ndolimax ItQnl10.7%). The Oi:lyonecaseof helminthparasitedetected was Strongyloidesstercoralis(0.9%).The sensitivity for detec-tion of B. homillis and T. homillis was increased by the LES culture technique. No history of diarrheasymptoms were recorded among these orphans. However. during the investigation, stools of allinfected cases were noted for six characteristics including formed, soft, loose, mucous, loose-wateryand watery.

The present study emphasized the problems of protozoan infections among these orphans.Heal,,",o:-'il!catkm:::.s well ~::;routi;;e :;urveillu;!ce is nec~s;;ary in order to contr01 t:;e infcc,i0iis.

Key word: Intestinal Parasite, "Orphanange Children. Orphanage

SAKSIRISAMPANT W, NUCHPRA YOON S,WIWANITKIT V, YENTHAKAM S, AMP AVASIRI AJ Med Assoc Thai 2003; 86 (Suppl 2): S263-S270. .

'--

. o.:r:l:1mcnI t)! I'ara:iltoloo y.. O'". ~ro.mm~nt of Lahorlatory Medicine. Faculty of Medicin~. Chulalongkorn University. Bangkok 10330.

(::r..c tlf Prcvc.-nrionand Resolution of Woman and Child Trafficking. Depanment of Social Development and.~~ '1',,!,,~) "f S0cial Devel0pmen! and Human Sec"nly. P:Hhum Thani 12110. Thailand.

S2fH w. SAJ\SIRIs.4,\IJ'ASr ,.t (11

Preo;entlv.manv of the health is:;uc'\ amnii!!

children li\'ing in orphanages in deyelopinf: countrie.;hJve been rJised( I). With about 62 millil)n peopleand a quJner of a million binhs each year in Thai-land.therearecommonhealth issuesthatehildn:nfacedaily. whether in or out of orphanages. Obviously.limited financial resources is the major cause ofchildren being ahandoned in Thailand, Orphans area group of underprivileged children in th~ society,Medical problems are generally compounded inorph;.II1agesbecause children are of!en abandonedwhen they are very young and do not ha\'e Jccess toJppropriate medical facilities( \.2). Failure to diJg-nose parasitic infections can contribute to continuedmalahsorption and failure to thriveO).

Among these parasites, protozoan infections(e!!..giardiasis) frequently affect children. The infec-

ti;ns~are often fou~d in ~symptomatic indiyiduals(4).However, the symptoms can range from mild diarrh~a.flJtulence. Jnorexia. crampy abdominal pains. andepigastric tenderness, to steatorrhea and full-blownmalabsorption syndrome. In addition. BhwocysrisI",milli,' ""hid.. has rt>C't"iw:cImuch atlt'nli"n in Ihp'

pJst t\\'o decades. has been detected widespread fromstool samples of a variety of populations of immuno-competent persons. with or without gastrointcstinalsymplOms(4.5). These protozoan infections were sub-stantially detected in Thai orphans, and children inday care centers of many other countries(5-!). Here.the authors repon the high prevalence of intcstinalprotozoa among children in an orphanage in PathumThani provice. Thailand. The present findings renectthe necessity for appropriate hcalth care :.II1deduca-tion JS public health strategies for the staff working\\ ith this group of children.

~r1ATERIAL A~D METHOD

Study area and participantsOn the occasion of the R4 the annin'rsary

of thl' folll1dinr of rhlllalnnrkom (!nivcr"ity ,he-authors visitcd a government orphanage during April.200 I in Pathum Th;mi prnvin~e. Thail;lIld. Its loca-tion is al1out 50 km from Bangko"~ tI\~ capital ofThailand, This cC11Ieris under the CI'Introl"f thl' Pre-\'l~ntionand Resolution of Woman and Chil.! Traffick-

ing Division. Department of Social Dc\dopmentand Welfare. tvlinistry of Social Devclopme11landHuman Security and n:sponsible for the ear~ of pre-school age orphans (1-7 years). The pre~nt study'aimed to help the Thai public. The orphans wcre fromimpoverished families or broken homes. abandoned

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In hospitals or public places :.IIldfrom I.unilies underdi\tress \\hose parents arc chronically Ill, mentallyillor imprisoned, All had no history of HIV infectionand wae recruited for this study. The paramedicalstaff and childcare \\orkers dealt directly with thechildren. After the stool samples were all collected

the authors took the specimens from the orphanag~to be tested, Informed consent was obtained from thesuperintendent. Khun Anchalee Ampava~!fi <mother.superior) before the ~tudy. After the study. drug treat.ment was given to allthe victims in the orphanaae

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Examination for stool parasites .Stoolspecimenswerecollectedand examined

for parasites by simple smear preparationandforma.lin-ether concentration technique. Each sample wasalso cultured in Boeck and Drbohlav's Lock-Eau.cc

Serum (LES) medium at -:.i;c for 48 h by modlfica.lion as described by Sa\\angjaro.:n N et al. 1993 to

ensure a high detection rate as some protozoa from

the microscopic examination may yield a negativeresult. (eg: E. hi.ITofyrica. B. !/Omill;:; Olll! T. !Wlllillis)(8) Tht" mndifil'ct acid-fa.., and modified trichrome.

special stains for C0pws!'orid;1II1/ /)(/1'1'11111and l'vficro.

sporidium si'p. were also performed. These stainingconditions were optimiled ao;descriht.'J by Gan:ia et at

1983 and Ryan ct al. 1993(9.10). .

RESULTS

, All 106 pre-school orphans (60 males and46 females) in the center were examined for the pr~'sence of intestinal parasites by th.: described lech.niques, The children ranged in age from 10months1081 months 06.1 ==15,0 months). Intt:rcstingly. moSIof the parasitic organisms found were protozoa, Onlyone case of helmithic infe('tion caused by S. -s'rt'r(()'/"litiswas detected.

The overall infh.tion rate was very high

(X1.1q). A higher pre"alcnce was found in femalesIR9 1C;fI than male.. 17~,nrf I with statistical,signifi-

cance (p < O,OS!.Children aged 25-36 months hadt~highest infection rate 191.1Ctf.Table I). Among tt\(investigated stool specimens. all six characteristicSwere noted includin~ formed. soft. loose (mushy\.

mucous. loose-wate;y tli4uidy) and watery (Tablc.'I). Typing of the slOols 1'0110\\cd that described byWHO( 11). All infected :;tool sampks were either t~formed type or otl)ers.

. \Vith regard to the Pf,)tozoa found. the high;~prevalence was B. !wm;II;,~(45.2':';,).There were3~per cent and 3.7 per cent positive with G. lal1lbliaa

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were non-pathogenic including T. homil/i" (39.6<7c). E.coli (18.89(;) and E. /IQ/Ill 0.7%), respectively (Tablc2). Interestingly, the culture technique using LESmedium .provided a much higher sensitivity comparedto the simplc smear and conccntration technique: 4-tcases compar~d to 5 by ~imple smear and 6 by con-centration for B. homi/lis and 39 cases comparcd to 5by simple smear and 3 by concentration for T. holllil/is

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DISCUSSION

Generally, the prevalence rates of intestinalparasitic infections vary from one area to another

depending on the degree of personal and communityhygiene, sanitatio.n and climatic factorsO,I3). Con-sequemely, the OCcurrenceof parasitic infections aremost commonly due to high-risk behaviors in unedu-

cated or unconcerning individuals. The public health!"1urdenof intestinal infectious diseases is substantial.

particularly among children worldwide includingunderprivileged children. It is accepted that living ina orphan gage shapes the child's health and develop-ment(I.14).

According to the present study, a high preva-lence of protozoan infections among these orphanscould be observed and four-fifths of the children

carried at least one type of protozoa. The infection

prevalence was higher both for pathogenic and non-pathogenic protozoan than another orphanage studiedin Thailand(6,12). The general detection of protozoanin children aged over 12 months as reported fromother orphanages and other countries was also shownin the present study (Tal1le2)(I2-J?). B.ilOl1Iini.~ was

found at the highest prevalence (45.2%). Thc infec-tion rate of C. lall1blia in this orphanage was 37.7per cent. The prevalence of these commonly foundparasites (B. homillis and C. lamblia) in abandonedchildren of other countries varied from 14.0 per cent

to 51.0 per cent( 13-16).The sources of infections maybe natural reservoirs (eg. food providers. domesticanimaic; or conlamin:Jtl'n fnnli nr w:Jtl'r)( 17) Tht' prt'-scnt study was not carried out on the childcare staff.

Morc epidemiological studies in theseindividuals willprm Idc the necessary information to aci-Jieve waysIQ pre\'cnt and control the infections. B. !lOmini.\', was

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generally considered to be a nonpathogenic yeast inthe past. but this organism has protozoan affinitiedue to the basis of rRNA sequencingC18). Muchauen~tion has been focused on it in the past two decadesprincipally because of its c1assificaiion as a protozoan:It is indeed frequently found in patients with gastro-intestinal disorders. However. studies by Udkow andMarkell in 1993 showed that in a blinded examina-

tion of the stools of both asymptomatic and symp-tomatic persons. essentially the sam~ prevalence ofBlastocystis was found. It has now been presentedinat least four serologic variants and its pathogeneni-city remains highly questionable(7), Funhermore. theauthors showed that the LES medium culture systemgreatly increased the sensitivity for protozoan detec-

tion especially B, hominis and T. hominis, (Fig. I)This confirms the principle that the vegetative formof these protozoa are viable in culture mediawhich

are superfluous(8.19). This is why the present reponshowed higher positive protozoan infectionsthanarepon from the Phayathai Babies' Home. Bangkok(12) which did not use the culture technique. In addi.tion. in the rural area of Pathum Thani province.thereare more underlying factors which may influencetheprevalence of these protozoan infections comparedto an urban or city area panicularly in Bangkok.Themethod of investigation was more pronounced in thedifferent sensitivity or the outcome results, Apartfrom G. lamblia. the other alimentary flagellateisDientamoeba fragilis. A number of repons indicatedthat it can cause symptoms in some infectedpersons(4). However. the present study did not find thisorganism either by simple smear or by LES culture.Although this LES medium W35reponed to be themost efficient for this organism cultivation(2). failureof this trophozoite to grow may be due to the processof stool collection which provided non-fresh speci-mens. It is common for D, fragi/is to degenel3lerapidly after leaving the stooi for 12-24 11at room

temper:.1ture(8.20). . .Curiously. during the pr~sent investigation.

no diaIThea sysmptoms among the childrenwerereported by the paramedical staff and from thehaI~

, fectt\!records. However the stool type of most 10. . ()lIScases were found to be either loose or soft or mUC- I thereweltor loose-wateryor watery. Untonunate y. .

no data of stool types from the other studiedorpha'nages(6.12.13). However. it is very difficultto ~

. , hildrenSincethe symptoms in parasitic infectIOn In C

"01. 86 Suppl 2INTESTINAL PARASITE A1\ION(; PATHl!1\t THAN! ORPH,\:--;A(;E UIILOREN S267

Table 3. Prevalence of protozoan infections between orphanage childrenfrom a previous study and the present study.

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inCHUSedf.ensitivity for rlrteciion of B. l:om;tI;.I' and T. /u'III;"is b~' Roeck and ))rhohla,"s Lockl'.EggSerum (LES) culture. When compared to simple smear (sim) and com:enh'atioll (c<in) techniques.

notonly parasitescan cause diarrhea but also othergastrointestinalillnesses which could he mild or non-

specific.Moreover, infal~:s and toddlers arc unable

to describethl' symptoms themselves.11is worth noting that the prc\alel1l:e of

helminthinfection was markedly 10\\: in this orpha-nage,A similar finding was also reported by Termll1a-thurapojet al. in Phayathai Children's home. Bangkok(12)Th

' ,

. IS!S not entirely unexpected oecause mass-

therapyof albendazolc, an anti-helminthic drug. is

Usuallycarried out yearly under the poli'y of the

Department ~:f S~:;::;:! !)'C',.,:'rT""'t1' :Inn Wc>lfare.

Ministryof Social Development and Human Security,Contrary to the present study. C. {'II/T/l1I/

and MierOSi)("": ' l '

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JU 'rl hI> , 1l",',-','d In X (, per"'"u""'t'J"'.u,...,.., ,

ccnt and 1.3 per cent. respectively. at Phayalhai

Bahies' home, Bangkok. However, 4R of 266 cases in

that orphanage wae those with HlY-positive children.Among these immunocoll1promised children. 4 l'ascsanti) cases ilati cr) pt\l.:;pvriJie~:s and microspnridio-sis respectively! 12), These infections were signifi.cantly more common in the HIY-infectcd group(4.21). The other rc;,;sonfor the negative finding of thesecoccidian in the present study might be that cryplo-sporidiosis is waterborne and outbreaks have alloccurred in communities where waleI' utilities met

state and federal st;JI1dart!s(4), In addition, the method

used tor l'ocuJlan 'tallllng in the present study might

pro\'llk t!rllt':l'nl ..r ',.., cl' sensitivity when compared

'.' thl' ;,'.:.r; ,'.,' -. i om:l1;.tt!1UrapOj ct al. Ho\\.-

S268 w. SAKS/JUSAMPANT el al.

ever, the disease is also now recognized as a zoono-sis which may be acquired trom domestIc animals(17). The source for infecting humans and the modesof transmissionof microsporidiosis are uncertain(4). .

Nevertheless. orphanages and day care cen-ters have been implicated as a major site of signifi-cant endemic giardiasis and transmissionO.15.16). Areport on severe giardiasis in the United States by theCenters for Disease Control and Prevention identified

two high-risk groups: children younger than 5 yearsof age and women of child bearing age(l.4.16). Iso~enzyme characterization of Giardia isolates suggeststhat domestic animals (cattle. sheep. dogs) may alsoserve as reservoirs for cross-transmission between

humans and animals(4). The surveys of prevalence inother orphanages. in childcare-workers and natural

j Med Assoc T:-'iii

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reservoirs remain to be done: Health care .Coverageamong orpnans ISrecomrnelluc:u.

ACKNOWLEDGEMENTS

The authors wish to thank Miss Jarrurau

Prownebon for random reexamination of the speciallystained slides of modified acid-fast and modifiedtrichrc-m.e-<-!Oall the paramedical staff and childcare

workers at Pathum Thani Orphanage for their helpin stool collection and to Dr. Sao,":aneeLeelayoova.Department of Parasitology. Phramongkutklao Col.lege of Medicine for her meaningful suggestions. .

This study was carried out to help the Thaipublicand wasset up by the vice-presidentfor Human

Resources Management and Procurement. Chula.longkom University.

(Re~,:i\led for publicalion on April 21. 2003)

rot. 86 Suppl 2INTESTINAL PARASITE AMONG PATHUM THANI ORPHA:--IAGE CHILDREN S269

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