Soil-transmitted helminthiases are a group of parasitic infections caused by roundworms, hookworms and whipworms. They are transmitted through contact with soil contaminated with human faeces containing worm eggs or larvae.
These infections occur in areas where there is inadequate sanitation and hygiene, and unsafe water. STHs are a particular threat to children as they impair physical and cognitive development. One of the major side effects is blood loss: a particular threat for women as they risk iron deficiency anaemia and having babies of low birthweight.
It is estimated that around 1.5 billion people in the poorest parts of the world are infected. Global efforts to control STHs focus on mass drug administration programmes, health education, and improvements in water, sanitation, and hygiene (WASH).
Many infections are mild or asymptomatic, particularly when people only have a few worms. Symptoms usually increase in severity with higher worm loads and can vary depending on the type of worm.
Common symptoms include:
Specific complications depending on worm type may include:
Heavy or chronic infections can lead to serious complications, particularly in children and vulnerable populations. Nutritional deficiencies and anaemia are common due to intestinal blood loss and the body being unable to get the nutrients it needs from food. Severe infections can cause intestinal obstruction, stunting and cognitive impairment. Children who are severely affected struggle at school and work – when whole communities are badly impacted this can have huge consequences for broader economic and social development.
STHs are transmitted primarily through faecal-oral contact. Eggs or larvae present in contaminated soil can enter the body when people consume food or water that has been in contact with the soil. Hookworm larvae can penetrate the skin, usually when people walk barefoot. Poor sanitation, open defecation, and inadequate hygiene practices significantly increase the risk of infection.
Antiparasitic medications, most commonly albendazole and mebendazole, are effective against a broad range of intestinal worms.
Prevention focuses on reducing exposure to contaminated soil and improving sanitation. In areas where the worms are prevalent those most at risk – children, women of childbearing age and pregnant women – are given drugs as a preventive therapy.
Key strategies include:
Intestinal helminth parasites have afflicted humans throughout history and their eggs have been detected in archaeological deposits throughout the world, including western Europe. While they are now rare in the richest countries, largely thanks to improvements in sanitation, a study in the American Journal of Tropical Medicine in 2017 found that one in three people in a poor part of Alabama tested positive for hookworm.
In 2012 a range of bodies – including the World Health Organization, charities and governments – pledged to eliminate STHs, by 2030. Since then the number of people receiving preventive treatment has increased from 260,000 in 2011 to 450,000 in 2023, although this is still only around half the number of people that need it.
who.int/fact-sheets/soil-transmitted-helminth-infections
unitingtocombatntds.org/Intestinal-worms-soil-transmitted-helminths/
Protect yourself and your family by learning more about Global Health Security
此内容由惯性聚合(RSS阅读器)自动聚合整理，仅供阅读参考。 原文来自 — 版权归原作者所有。