[Intestinal parasitic infections in Serbia]
Nikolic A. Djurkovic-Djakovic O. Bobic B.
Institute of Medical Research, Belgrade.
To determine the public health significance of intestinal parasitism in Serbia today, systematic parasitologic examination of 16 regions (Kragujevac, Luchani, Zhagubica, Bor, Sjenica, Novi Pazar, Valjevo, Aleksandrovac, Pirot, Bosilegrad, Ivanjica, Golubac, Uzhice, Kladovo, Negotin, Beograd) in central Serbia were carried out over the period 1984-1993. The study involved a total of 5981 schoolchildren (2887 F, 3094 M), 7-11 years old representing 10% of the total age-matched population (N = 58,228) of the examined regions, residing in 91 settlements. Field parasitological examinations included the examination of perianal swabs for E. vermicularis and Taenia sp., and examination of a single feces sample by direct saline smear and Lugol stained smear for intestinal protozoa, and the Kato and Lorincz methods for intestinal helminths. Nine species of intestinal parasites were detected, of which five protozoan: Entamoeba histolytica (0.02%), Entamoeba hartmanni (0.02%), Entamoeba coli (1.3%), Iodamoeba butschlii (0.02%), Giardia lamblia (6.8%), and four helminthic: Hymenolepis nana (0.06%), Enterobius vermicularis (14.7%), Ascaris lumbricoides (3.3%), Trichuris trichiura (1.8%). The overall prevalence of intestinal parasite infections amounted to 24.6% (1207/4913), with a highly significant difference (p < 0.001) between particular sites (range 14.4%-43.8%) (Figure 1). Helminthic infections (810) were significantly more frequent (p < 0.001) as compared to both protozoan (296) and combined helminthic-protozoan infections (101). Of these, two species (G. lamblia, E. vermicularis) were found in all examined regions, three (E. coli, A. lumbricoides, T. trichiura) were detected in two or more, while four species (E. histolytica, E. hartmanni, I. butschlii, H. nana) were each found in a single region (Figure 2). The predominant species (E. coli, G. lamblia, E. vermicularis, A. lumbricoides, T. trichiura) were distributed at considerably different prevalence rates, with a significant difference between the minimal and maximal values (p < 0.01). Of 91 settlements examined, intestinal parasites were found in all but one. However, the prevalence rates in 90 settlements varied significantly (p = 0.0004), from a low of 5.9% to a high of 66.7%. Thus, according to the World Health Organization criteria , infections with the four clinically relevant species (G. lamblia, E. vermicularis, A. lumbricoides, T. trichiura) ranged from sporadic to endemic and hyperendemic (Figure 3). The results obtained provide the basic epidemiological data about intestinal parasite infections in Serbia, and indicate their significance in terms of both the number of species and their respective prevalence rates. Given the significant differences obtained in the frequency and distribution of particular parasite infections in different regions, a programme for the control of these infections in Serbia should obviously include a wide variety of measures.