©2020 Institute of Parasitology, SAS, KošiceDOI 10.2478/helm-2020-0033

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HELMINTHOLOGIA, 57, 3: 276 – 279, 2020

Research Note

The prevalence of intestinal parasitic infections among Kosovar and Serbian school-children in Kosovo

K. KORZENIEWSKI1,*, A. LASS2, A. AUGUSTYNOWICZ1, M. KONIOR1

1Military­Institute­of­Medicine,­Department­of­Epidemiology­and­Tropical­Medicine,­83-103­Gdynia,­4­Grudzińskiego­St.,­Poland,­*E-mail: kkorzeniewski@wim.mil.pl; 2Medical­University­of­Gdańsk,­Institute­of­Maritime­and­Tropical­Medicine,­

Department­of­Tropical­Parasitology,­81-519­Gdynia,­9B­Powstania­Styczniowego­St.,­Poland

Article info

Received­July­18,­2019Accepted­May­5,­2020

Summary

The­aim­of­this­study­was­to­estimate­the­prevalence­and­distribution­of­species­of­intestinal­para-sites­in­the­Balkans­on­the­example­of­Kosovar­and­Serbian­residents­from­the­region­of­Gnjilane­in­eastern­Kosovo,­where­the­epidemiology­of­intestinal­parasitic­infections­remains­unknown.­Para-sitological­examination­of­stool­specimens­was­performed­in­2017­and­2018.­Stool­samples­were­collected­from­asymptomatic­school-children­aged­6­–­17­years:­530­Kosovars­from­the­municipality­of­Kaçanik­and­310­Serbs­from­the­municipalities­of­Kamenica­and­Strpce.­Each­patient­provided­two­stool­samples­collected­every­second­day,­fi­xed­in­SAF­preservative­and­70­%­spiritus­vini,­transpor-ted to the Department of Epidemiology and Tropical Medicine at the Military Institute of Medicine in Poland,­and­tested­by­light­microscopy­using­three­diagnostic­methods:­direct­smear­in­Lugol’s­solu-tion,­decantation­in­distilled­water,­and­Fülleborn’s­fl­otation.­A­total­of­101­Kosovar­children­(19.1­%­of­the­study­group)­were­found­to­be­infected­with­intestinal­parasites:­nematodes­(n=20),­cestodes­(n=2),­trematodes­(n=2),­and­protozoa­(n=79).­Only­13­Serbian­children­(4.2­%)­were­found­to­be­infected­with­ nematodes­ (n=4),­ cestodes­ (n=3),­ and­ protozoa­ (n=6).­Giardia intestinalis­was­ the­most­prevalent­ intestinal­parasite­ in­both­groups­ (14,9­%­vs.­1.9­%­children).­The­prevalence­of­asymptomatic­parasitic­ infections­was­signifi­cantly­higher­in­Kosovars­in­comparison­to­the­Serbs­living­in­the­same­region­of­eastern­Kosovo.­This­fact­shows­that­there­may­be­signifi­cant­differences­in­the­quality­of­health­care­and­sanitation­as­well­as­feed­hygiene­between­these­two­communities.Keywords:­helminths;­protozoa;­children;­epidemiology;­Kosovo

Introduction

Despite a spectacular advance in the diagnosis and management of­ diseases,­ intestinal­ parasitic­ infections­ remain­ a­major­ public­health­ issue­globally­(Keiser­and­Utzinger,­2010).­ It­ is­estimated­that­more­ than­ two­billion­people­worldwide­are­ infected­with­at­least­one­species­of­intestinal­parasite­and­over­fi­ve­billion­people­live­in­countries­where­helminths­and­protozoa­are­endemic­(Kucik­et al.,­2004).­The­risk­of­infection­is­particularly­high­in­areas­with­poor­sanitation­because­poor­hygiene­and­ the­ lack­of­adequate­

sanitation­facilities­encourage­the­spread­of­food­and­waterborne­diseases­(Hotez­et al.,­2007).­There­are­a­number­factors­which­facilitate­the­spread­of­parasitic­infections­both­in­the­developing­and­the­industrialized­world;­these­include­low­socioeconomic­sta-tus, mass migrations, and the presence of hosts in ecosystems (reservoirs­of­parasites)­(Ali­et al.,­2014;­Ojha­et al.,­2014).­The­spectrum­of­clinical­symptoms­in­parasitic­infections­is­extremely­wide­and­may­vary­ from­asymptomatic­cases­ through­diarrheas­to­cachexia­leading­to­severe­anemia­(Korzeniewski­and­Kurpas,­2016).­Microscopic­examination­ is­still­ the­gold­standard­ for­ the­

* – corresponding author

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­diagnosis­of­intestinal­helminths­and­protozoa­making­it­possible­to­detect­parasites­at­their­different­developmental­stages­(cysts,­trophozoites,­ larvae,­ ova)­ (Myjak­ et al.,­ 2011).­ In­ Europe,­ high­rates­of­parasitic­infections­are­reported­from­the­countries­which­are listed in the third and fourth quartile according to gross domes-tic­product­per­capita­(GDP­$1­809­–­$17­630)­(Hotez­and­Gur-with,­2011);­Kosovo­ranks­in­the­4th­quartile.­The­exact­prevalence­of­parasitic­infections­in­Kosovo­is­not­clear­because­the­country­lacks­organized­epidemiological­screening.­In­2001,­a­study­was­conducted­to­establish­the­etiology­of­diarrhea­in­45­Kosovar­chil-dren­(Kosovska­Mitrovica).­ It­ revealed­ that­40­%­of­ the­diarrhea­cases­in­the­study­group­were­associated­with­Giardia intestina-lis­ (Quamilè­et al.,­2011).­Another­study­aimed­at­assessing­ the­prevalence­of­parasitic­infections­in­Kosovo­was­conducted­by­the­authors­of­the­present­article­in­2015.­The­study­group­consisted­of­632­Kosovars­(children­and­adults)­living­in­the­municipality­of­Kaҫanik­located­in­southern­Kosovo.­We­found­that­12­%­of­the­study population had asymptomatic parasitic infections, mainly Giardia intestinalis infection­(10­%­of­the­infected­individuals)­(Ko-rzeniewski­and­Augustynowicz,­2017).­Kosovo­has­a­population­of­around­2­million­people.­The­majority­of­its­residents­are­Albanian,­but­ there­are­also­some­significant­ethnic­minorities­ living­ in­ the­country,­of­which­the­Serbian­minority­is­the­largest­(140,000).­The­aim­of­this­study­was­to­assess­the­prevalence­and­distribu-tion­of­species­of­intestinal­parasites­in­the­Balkans­on­the­exam-ple­of­Kosovar­and­Serbian­residents­from­the­region­of­Gnjilane­in­eastern­Kosovo,­where­the­epidemiology­of­intestinal­parasitic­infections­remains­unknown.

Material and Methods

Study population In­ total,­ 840­ asymptomatic­ school-children,­ aged­ 6­ –­ 17­ years,­

living­ in­ the­ region­of­Gnjilane­ in­eastern­Kosovo­ (including­530­Kosovars­from­the­municipality­of­Kaçanik­and­310­Serbs­from­the­municipalities­of­Kamenica­and­Strpce)­were­screened­for­intesti-nal­parasites­in­2017­and­2018.­The­approval­to­perform­the­study­involving­Kosovar­children­had­been­given­by­the­Head­of­Medical­Service­and­Social­Health­Department­Mrs.­Diana­Reka­and­the­Head­of­Education­and­Culture­Department­Mr.­Enver­Kamishi­and­issued­in­the­Kaҫanik­municipality.­The­approval­to­perform­a­re-search­study­among­Serbian­children­had­been­obtained­from­the­Director­of­Medical­Center­for­the­Gnjilane­region,­Dr.­Zoran­Perić.­Written­informed­consent­was­provided­by­parents­or­legal­guard-ians­of­the­children­involved­in­the­study­(handwritten­signatures­on­a­collective­list­of­all­study­participants).­The­details­of­the­study­were­explained­to­the­participants­in­patient­information­brochures­written­in­the­Albanian­and­Serbian­languages.­

Sample collection and laboratory procedures Each­ patient­ provided­ two­ stool­ samples­ collected­ every­ sec-ond­ day­ at­ Kosovar­ and­ Serbian­ healthcare­ facilities­ and­ local­schools.­The­specimens­were­fixed­in­SAF­(sodium-acetate-ace-tic­acid-formalin)­preservative­and­70­%­spiritus­vini,­transported­to the Department of Epidemiology and Tropical Medicine at the Military­ Institute­ of­ Medicine­ in­ Poland,­ and­ tested­ by­ light­ mi-croscopy­using­three­diagnostic­methods:­direct­smear­in­Lugol’s­solution,­decantation­with­distilled­water,­and­Fülleborn’s­flotation­(Clinical­and­Laboratory­Standards­ Institute,­2005;­Garcia­et al., 2003;­WHO,­1991).­Statistical analysis The­statistical­analyses­have­been­performed­using­the­statistical­suite­StatSoft­Inc.­(2014)­STATISTICA­(data­analysis­software­sys-tem)­version­12.0.­www.statsoft.com­and­Excel.­The­quantitative­variables­were­characterized­by­the­arithmetic­mean­of­standard­deviation­or­median­or­max/min­(range).­The­qualitative­variables­

Intestinal parasites No of infections

(n=103)

% of infections

% of examined patients (n=530)

Nematodes 20 19.5 3.8Ascaris lumbricoides 8 7.8 1.5

hookworm 8 7.8 1.5Trichuris trichiura 3 2.9 0.6

Enterobius vermicularis 1 1.0 0.2Cestodes 2 1.9 0.4

Hymenolepis nana 2 1.9 0.4Trematodes 2 1.9 0.4

Dicrocoelium dendriticum 2 1.9 0.4Protozoa 79 76.7 14.9

Giardia intestinalis 79 76.7 14.9No of infected 101 100.0 19.1

Table­1.­­Intestinal­parasitic­infections­among­530­Kosovar­school-children­residing­in­Gnjilane­region­(Kaçanik­municipality).

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were­presented­with­the­use­of­count­and­percentage.­A­statistical­significance­level­of­0.05­was­used­for­all­calculations.­

Ethical Approval and/or Informed Consent The­research­project­was­approved­by­ the­Bioethics­Committee­at­ the­Military­ Institute­ of­Medicine­ in­Poland­ (Decision­No.­ 72/WIM/2017)­under­the­Declaration­of­Helsinki­and­in­line­with­the­EU provisions on Good Clinical Practice for conducting clinical tri-als and testing medicinal products­signed­by­the­Polish­Bioethics­Committee.­

Results

Following­the­microscopic­examination­of­1,680­stool­specimens­(two­samples­ taken­ from­each­of­ the­840­subjects)­by­ three­dif-ferent­ light­ microscopy­ methods­ we­ found­ that­ the­ total­ preva-lence­of­ intestinal­parasites­was­19.1­%­in­Kosovar­(n=530)­and­4.2­%­in­Serbian­school-children­(n=310).­The­study­revealed­that­101­ Kosovar­ children­ were­ infected­ with­ pathogenic­ intestinal­parasites;­ a­ total­ of­ 103­ infections­were­detected­ (two­ cases­of­co-infections).­ The­most­ frequently­ detected­ intestinal­ parasites­included Giardia intestinalis (14.9­%­study­subjects),­Ascaris lum-bricoides­(1.5­%)­and­hookworm­(1.5­%)­(Table­1).A­ total­of­13­Serbian­children­were­ found­ to­be­ infected­with­ in-testinal­parasites.­Giardia intestinalis­ (1.9­%­of­ the­study­group)­and Ascaris lumbricoides­(1.0­%)­were­predominant­(Table­2).­In-fections­with­non-pathogenic­intestinal­parasites,­e.g.­Enatmoeba coli, Endolimax nana, Chilomastix mesnili­(found­in­both­examined­groups)­were­not­taken­into­consideration­and­are­not­discussed­in­this­paper.­

Discussion

Current­epidemiological­situation­of­ intestinal­parasitic­ infections­(IPI)­ in­Kosovo­ is­unknown­and­presented­study­remains­one­of­

few­analyses­ in­ the­field­of­ intestinal­parasitology­ in­ this­ region.­Population­screening­ to­assess­ the­prevalence­of­ intestinal­par-asites­have­been­carried­out­in­the­neighboring­countries,­e.g.­in­Albania­ and­Serbia.­The­ study­ of­ Sejdini­et al.­ (2011)­ involving­321­children­(aged­7­–­16­years)­ living­ in­ the­counties­of­Tirana­and­Elbasan­ in­ central­Albania­ demonstrated­ the­ overall­ IPI­ in-cidence­of­19.0­%,­ the­most­prevalent­being­Giardia intestinalis (10.9­%),­hookworm­ (5.6­%),­and­Ascaris lumbricoides­ (1.9­%).­A­different­screening­study­performed­by­Spinelli­et al.­ (2006)­ in­277­asymptomatic­subjects­ from­central­Albania­ found­ that­24.2­%­of­the­study­group­were­infected­with­pathogenic­protozoa­and­helminths, including Trichuris trichiura­(12.3­%),­Giardia intestina-lis­(11.2­%),­Hymenolepis nana­(1.8­%)­and­Ascaris lumbricoides (1.1­%).­The­authors’­study­involving­530­asymptomatic­Kosovar­school-children­ from­ the­Gnjilane­ region­demonstrated­a­ similar­overall­incidence­of­IPI­(19.1­%),­where­the­most­commonly­iden-tified­parasites­ included­Giardia intestinalis­ (14.9­%),­hookworm­(1.5­%)­and­Ascaris lumbricoides­(1.5­%).­According­to­the­research­studies­conducted­in­Serbia,­the­rates­of­ infections­with­ intestinal­ parasites­ in­ the­ local­ population­ are­relatively­ low.­ A­ multicenter­ screening­ of­ 6,645­ asymptomatic­school-children,­ aged­ 7­ –­ 11­ years,­ from­ 115­ settlements­ in­ 20­different­ regions­ of­ central­ Serbia­ (including­ Belgrade,­ Kraguje-vac,­ Lučani,­ Bor,­ Žagubica,­ Sjenica,­ Novi­ Pazar,­ Valjevo,­Alek-sandrovac,­ Pirot,­ Bosilegrad,­ Ivanjica,­ Golubac,­ Užice,­ Klado-vo,­ Negotin,­ Kraljevo,­ Gornji­ Milanovac,­ Kruŝevac,­ and­ Čačak)­found the overall prevalence of Giardia intestinalis infections to be­6.1­%.­(Nikolić­et al.,­2011).­The­authors’­study­conducted­ in­the­period­between­2017­and­2018­among­310­asymptomatic­Ser-bian­school-children­from­the­Gnjilane­region­in­eastern­Kosovo,­demonstrated­the­overall­incidence­of­IPI­at­4.2­%,­with­Giardia in-testinalis­(1.9­%)­and­Ascaris lumbricoides­(1.0­%)­being­predom-inant.­Examination­of­2,440­Serbian­travelers­returning­from­tropi-cal­and­subtropical­destinations­revealed­infections­with­intestinal­parasites­in­1.2­%­patients­only,­mainly­Entamoeba histolytica sen-su lato and Giardia intestinalis­(Dakić­et al.,­2011).­In­recent­years,­

Intestinal parasites No of infections

(n=13)

% of infections

% of examined patients (n=310)

Nematodes 4 30.8 1.3 Ascaris lumbricoides 3 23.1 1.0­

Enterobius vermicularis 1 7.7 0.3Cestodes 3 23.1 1.0

Hymenolepis nana 2 15.4 0.7Diphyllobothrium latum 1 7.7 0.3

Protozoa 6 46.1 1.9Giardia intestinalis 6 46.1 1.9

No of infected 13 100.0 4.2

Table­2.­Intestinal­parasitic­infections­among­310­Serbian­school-children­residing­Gnjilane­region­(Kamenica­and­Strpce­municipality).

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a­majority­of­studies­into­the­prevalence­of­intestinal­parasites­in­humans that are carried out in Europe are primarily focused on the incidence of Cryptosporidium­spp.­and­Giardia­spp.­Serbia­is­one­of­the­countries­participating­in­IPI­surveillance­(the­number­of­reported­giardiasis­cases­in­the­country­fell­from­4.6/100,000­in­2005­to­1.1/­100,000­in­2014)­(Plutzer­et al.,­2018).­Unfortunately,­there­is­no­reliable­data­available­as­to­the­prevalence­of­intestinal­parasitic­infections­in­Kosovo.­

Conclusion

Current­ epidemiology­ of­ intestinal­ parasites­ in­ Kosovo­ is­ un-known.­ The­ study­ involved­ asymptomatic­ Kosovar­ and­ Serbian­school-children­ living­ in­ the­same­ecosystem­of­ the­Gnjilane­ re-gion­ (eastern­Kosovo)­and­demonstrated­ that­ the­prevalence­of­intestinal­parasitic­infections­in­Kosovars­is­significantly­higher­in­comparison­ to­ Serbian­ children,­ which­may­ be­ the­ evidence­ of­some differences in the quality of health care and sanitation as well­as­feed­hygiene­between­these­two­communities.­

Acknowledgements.

This­study­was­supported­and­co-funded­by­ the­Ministry­of­Sci-ence­ and­ Higher­ Education­ in­ Poland­ (project­ No.­ 518/2018,­2018­–­2019).­The­authors­are­grateful­ to­Mrs.­Diana­Reka,­Mr.­Enver­Kamishi­and­Dr.­Zoran­Perić­for­their­excellent­technical­as-sistance and supervision in patient recruitment and collection of biological­samples.

Declaration of interest

The­authors­declare­that­they­have­no­conflict­of­interest.

ReferencesAli, A.M., MAsud, T., Arif, s.­(2014):­Frequency­of­parasitic­infes-tation­in­faecal­specimens.­J. Ayub. Med. Coll. Abbottabad,­26(1):­49­–­51CliniCAl And lAborATory sTAndArds insTiTuTe­ (2005):­ Procedures­for­the­Recovery­and­Identification­of­Parasites­from­the­Intestinal­Tract:­Approved­Guideline,­M28-2A.­Villanova,­USADakić, Z., Nikolić, a., lavaDiNović, l., Pelemiš, m., kluN, i., Dulović, o., milosević, B., stefaNović, G., ofori-Belić, i., PoluGa, J., DJurk-ović-DJaković, o., Pavlović, m.­(2011):­Imported­parasitic­infections­in­Serbia.­Eur. J. Microbiol. Immunol.,­1(1):­80­–­85.­DOI:­10.1556/EuJMI.1.2011.1.10Garcia, l.s., smith, J.W., fritsche, t.r. (2003):­Selection­and­use­of­laboratory­procedures­for­diagnosis­of­parasitic­infections­of­the­gastrointestinal­tract.­ASM­press:­Washington­DC,­USAhoteZ, P.J., GurWith, m.­(2011):­Europe’s­neglected­infections­of­poverty.­ Int. J. Infect. Dis.,­ 15(9):­ e611­ –­ e619.­ DOI:­ 10.1016/j.ijid.2011.05.006

hoteZ, P.J., molyNeux, D.h., feNWick, a., kumaresaN, J., sachs, s.e., sachs, J.D., saviolo, l.­ (2007):­Control­ of­ neglected­ tropi-cal­diseases.­N. Engl. J. Med.,­2007;­357(10):­1018­–­1027.­DOI:­10.1056/NEJMra064142keiser, J., utZiNGer, J.­(2010):­The­drugs­we­have­and­the­drugs­we­need­against­major­helminths­ infections.­Adv. Parasitol.,­ 73:­197­–­230.­DOI:­10.1016/S0065-308X(10)73008-6korZeNieWski, k., auGustyNoWicZ, a.­(2017):­Parasitological­exami-nation­among­local­residents­ in­Afghanistan,­Central­African­Re-public­and­Kosovo­conducted­by­the­Polish­military­health­service.­Int. Rev. Armed Forces Med. Serv.,­90(2):­60­–­68korZeNieWski, k., kurPas, D. Diagnostics and treatment of para-sitic­diseases­of­the­gastrointestinal­tract.­Therapy,­2:­56­–­66­(In­Polish)kucik, c.J., martiN G.l., sortor B.v.­ (2004):­Common­ intestinal­parasites.­Am. Fam. Physician,­69(5):­1161­–­1168­myJak, P., GłoWNiak, c., GołąB, e., JaBoroWska-Jarmoluk, m., ko-sik-BoGacka, D., matoWicka-karNa, J., NoWak, P., PietkieWicZ, h., sZostakoWska, B., WNukoWska, N., ŻarNoWska-Prymek, h.­ (2011):­Standards­ in­ the­range­of­ laboratory­activities­ in­medical­parasi-tology,­ estimation­ of­ their­ quality­ and­ diagnostics­ value,­ as­well­as­interpretation­and­authorization­of­the­tests­results­(proposals).­Journal of Laboratory Diagnostics,­47:­341­–­351­(In­Polish)Nikolić, a., kluN, i., BoBić, B., ivović, v., vuJaNić, m., Živković, t., DJurković-DJaković, o.­(2011):­Human­giardiasis­in­Serbia:­asymp-tomatic­vs­symptomatic­ infection.­Parasite,­ 18:­197­–­201.­DOI:­10.1051/parasite/2011182197oJha, s.c., JaiDe, c., JiNaWath, N., rotJaNaPaN, P., Baral, P.­(2014):­Geohelminths:­ public­ health­ significance.­ J. Infect. Dev. Ctries, 8(1):­5­– 16.­DOI:­10.3855/jidc.3183PlutZer, J., lasseN, B., JokelaiNeN, P., DJurković-DJaković, o., kuc-sera, i., DorBek-koliN, e.­(2018):­Review­of­Cryptosporidium and Giardia­in­the­eastern­part­of­Europe,­2016.­Euro Surveill.­23(4):­pii=16-00825.­DOI:­10.2807/1560-7917.ES.2018.23.4.16-00825Quamilè, i., roGerie, f., GraNDaDam, m., teyssou, r., NicaND, e., koeck, l., feJZia, i., BuissoN, y., rey, J.l.­(2010):­Survey­of­diar-rhoea­survey­ in­Kosovo­Mitrovica.­August­2001.­Sante, 20(1):­9­–­14.­DOI:­10.1684/san.2009.0176­(In­French)SEJDINI,­A.,­MAHMUD,­R.,­LIM,­Y.A.,­MAHDY,­M.,­SEJDINI,­F.,­GJONI,­V.,­XHAFERRAJ,­K.,­KASMI,­G.­ (2011):­ Intestinal­para-sitic­infections­among­children­in­central­Albania.­Ann. Trop. Med. Parasitol.,­105(3):­241­–­250.­DOI:­10.1179/136485911X12987676649584sPiNelli, r., BraNDoNisio, o., serio, G., trerotoli, P., GheZZaNi, f., carito, v., DaJci, N., Doci, a., Picaku, f., DeNtico, P.­(2006):­Intesti-nal­parasites­in­healthy­subjects­in­Albania.­Eur. J. Epidemiol., 21: 161­–­166.­DOI:­10.1007/s10654-005-5926-3­WorlD health orGaNiZatioN­ (1991):­ Basic­ laboratory­methods­ in­medical­parasitology.­Geneva,­Switzerland­youNas, m., shah, s., talaat, a.­(2008):­Frequency­of­Giardia­lam-blia­ infection­ in­ children­ with­ recurrent­ abdominal­ pain.­ J. Pak. Med. Assoc.,­58:­171­–­174