Prevalence of intestinal parasitic infections in the population of Central Asia on the example of inhabitants of Eastern Afghanistan.

BACKGROUND: Parasitic diseases of the gastrointestinal tract are a major health problem worldwide, especially in the Third World countries, where poor standards of hygiene and sanitation as well as the lack of medical care facilitate the spread of food and waterborne infections.

AIM: To estimate the prevalence of intestinal parasitic infections in Central Asia on the example of the population inhabiting the Ghazni Province in eastern part of the country and to assess the validity of the WHO recommended mass deworming campaign carried out in Afghanistan. Taking into consideration the fact that hundreds of thousands of immigrants from Asia and Africa have recently been flooding into Europe, it has become necessary to investigate the epidemiology of intestinal parasitoses in areas characterized by different climatic conditions and poor standards of sanitation.

MATERIAL AND METHODS: The study was conducted in eastern Afghanistan between November 2011 and April 2014. Parasitological examination was performed on 3 different study groups: 110 soldiers from the Afghan National Army (adults), 1,167 patients hospitalized at the Ghazni Provincial Hospital (807 children and adolescents aged 1–18 and 360 adults), and 1,869 students (7–18 years) frequenting local schools. The study involved 3,146 people including: 2,248 females and 898 males; 2,676 children and adolescents (1–18 years) and 460 adults (19–85 years). Three stool samples were collected from each study subject at the intervals of 2 to 3 days. The samples were fixed in 10% formalin and then transported by air to the Department of Epidemiology and Tropical Medicine (Military Institute of Medicine) in Poland, where they were examined by light microscopy using 3 different diagnostic methods (direct smear in Lugol’s solution, decantation with distilled water, Fülleborn’s flotation).

RESULTS: In total, 1,220 Afghans were found to be infected with pathogenic intestinal parasites (38.8%): 44/110 soldiers (40.0%), 322/807 hospitalized children and adolescents (39.9%), 102/360 hospitalized adults (28.3%) and 752/1869 children and adolescents frequenting local schools (40.2%). Higher infection rates were observed in children and adolescents (40.1% vs. 31.1% adults), in boys (40.8% vs. 39.9% girls), and in the adult population – in women (31.2% vs. 31.0% men). The most commonly detected intestinal parasites in all study groups were: Ascaris lumbricoides (619/3146, 19.7%), Giardia intestinalis (489/3146, 15.5%) and Hymenolepis nana (206/3146, 6.5%).

SUMMARY AND CONCLUSIONS: The prevalence and diversity of intestinal parasitic infections is high in the population of Central Asia. The infections caused by a wide range of nematodes, cestodes and protozoa are common among inhabitants of eastern Afghanistan. This fact suggests that the WHO-recommended deworming strategy (a single dose of 500 mg mebendazole or 400 mg albendazole) needs to be reviewed and should be replaced by targeted antiparasitic chemotherapy (albendazole, metronidazole, praziquantel), following mass screening of the local population.