"Bundles" of large worms were found inside the stomach of a four-year-old boy who for three days had suffered stomach pains, vomiting and severe constipation.

“Bundles” of large worms have been found inside the stomach of a four-year-old boy.

The boy, who lived in the northwest of the Republic of Cameroon in Central Africa, had been suffering three days of stomach pain, vomiting, and was severely constipated, the Journal of Medical Cases reported.

His family told doctors his stomach had started to become distended about six months before.

When he was examined, doctors thought there was a small bowel obstruction, which prompted them to make a 2 cm cut. Surgeons then removed “bundles of Ascaris lumbricoides worms” manually and “by milking them through the stoma (the 2cm cut in his stomach).”

Ascaris lumbricoides, which is the large roundworm, can grow up to 35 cm in length.

An estimated 807 million–1.2 billion people in the world are infected with Ascaris lumbricoides worms (sometimes called just Ascaris or ascariasis), according to the US-based Centers for Disease Control and Prevention (CDC).

“Ascaris, hookworm, and whipworm are parasitic worms known as soil-transmitted helminths (STH). Together, they account for a major burden of parasitic disease worldwide,” CDC states.

Read next: Climate change reports Armageddon by 2050 unless action taken

The parasites live in the intestine and eggs are passed in the faeces of infected people. If an infected person defecates outside, or if the faeces of an infected person are used in fertiliser, eggs are deposited on the soil. The eggs can then mature into a form of the parasite that is infective.

Infection can occur when hands or fingers that have contaminated dirt on them are put in the mouth, or by consuming vegetables or fruits that have not been carefully cooked, washed or peeled, according to the CDC.

Heavy infections cause intestinal blockage and may impair growth in children. Other symptoms may present as a cough due to the migration of the worms through the body. It can be treated with medication, but in the boy’s case, surgeons decided to operate.

After the surgery, doctors dewormed the boy and his family members with an oral dose of mebendazole, and he was released after seven days. One week later, surgeons recorded that his wounds had healed.

Ascariasis most often affects those living in the warm, moist tropics, but few countries of the world are exempt. In 1979, it was estimated that between 800 million and 1 billion people were infected with Ascaris, ranking it third among the ten most common human infections.

It is particularly common throughout Asia, especially in China, India, Sri Lanka, Southeast Asia, the Philippines, Japan, Russia, Afghanistan, and Iran. It is also prevalent throughout Africa and Egypt.