Abstract:

A survey was performed on intestinal nematodes among primary and middle school students in Baise city from 2006 to 2016, using the modified Kato thick smear (Kato-Katz) method to examine worm eggs under microscope. The positive fecal samples were further used to culture hookworm larvae using the tube filter method, to identify the species of hookworms. Meanwhile, pinworms were examined by the transparent paper anal swab method for students under 12 years. A total of 10 273 students were examined, of whom 385 (3.75%) were infected with intestinal nematodes. The infection rate of intestinal nematodes was highest in 2006 (17.22%, 36/709) and lowest in 2016 (1.15%, 11/956). The infection rates of whipworm, roundworm, pinworm and hookworms were 2.25% (231/10 273), 0.79% (80/10 273), 0.67% (69/10 273) and 0.05% (5/10 273), respectively. The hookworms detected were all identified to be Ancylostoma duodenale. The four species all showed mild infection, and no mixed infection was found. The infection rate of intestinal parasites was 3.36% (180/5 361) in boys and 4.17% (205/4 912) in girls (χ² = 4.722, P < 0.005). The infection rate of intestinal nematodes was highest in the 6-year-old group (6.4%, 95/1485). Among different areas of residence, the infection rate of intestinal nematodes was highest in rural areas (13.11%, 110/839), and lowest in urban areas (2.44%, 212/8 692), with the rural-urban fringe areas in-between (8.49%, 63/742) (χ² = 291.445, P < 0.01). Those detected with intestinal nematode infection received deworming treatment with the compound albendazole. The results suggest a trend of decrease for intestinal nematode infections, and whipworm is the most common intestinal nematode.

Key words: Intestinal nematode, Baise City, Survey, Analysis