Gastrointestinal worm infections are common in countries with hot and humid tropical climates like Vietnam. Many cases of worm infection can cause dangerous complications such as: Severe anemia caused by hookworms, worms in the bile ducts, intestinal obstruction caused by worms, encephalitis, meningitis,... Most worms do not cause protective immunity. protection, worm diseases can still be re-infected after recovery.

In poor countries, children are likely to become infected with worms from the moment they stop breastfeeding and continue to be reinfected throughout their lives. Worm infections rarely have acute consequences for children, but instead lead to chronic infections that negatively impact child development, including health, nutrition, cognitive development, access to and achievement in school.