Giardia lamblia or Giardia duodenalis is a protozoan organism found in animals, humans, and environmental contaminants. The parasite was discovered by Antonie van Leeuwenhoek in 1681, while giardiasis, the disease caused by Giardia lamblia, was documented first in 1962. The epidemiological investigations suggested that the disease’s prevalence was about 0.85%, with the highest rate of infection 9.46%, as reported by researchers from Shanghai (as cited in Li et al., 2017). The disease is asymptomatic in adults, while children more frequently have symptoms. People with no symptoms can carry a cyst of the parasite for approximately six months (Leung et al., 2019). Other affected individuals might have acute diarrhea with watery stool in the beginning and greasy sometime later. Other symptoms include anorexia, malaise, nausea, bloating, vomiting, asthenia, fatigue, weight loss, and abdominal pain. Asthenia and abdominal pain are more common in children with giardiasis. In general, symptoms of the disease depend on age, the virulence of the parasite, and the individual’s immune response. The virulent factor of Giardia lamblia is a cysteine protease, which disrupts the small intestine (Leung et al., 2019). The diagnosis is performed by microscopic examination that detects cyst or trophozoite of the parasite in the stool specimens. The main goal of the treatment is to maintain electrolyte balance and regular hydration to minimize diarrhea’s duration. Many drugs have been suggested in symptomatic cases, among which are Metronidazole, tinidazole, and nitazoxanide (Leung et al., 2019). Among the prevention strategies are handwashing with water and soap. It is particularly crucial for children that visit hospitals as they are more likely to be infected. Purification of water in public places is also essential. As a water cleaning method, boiling can be suggested. If not treated promptly, the disease might result in severe electrolyte disbalance, chronic mucosal inflammation, lymphoid hyperplasia.
References
Leung, A. K. C., Leung, A. A. M., Wong, A. H. C., Sergi, C. M., & Kam, J. K. M. (2019). Giardiasis: An overview. Recent Patents on Inflammation & Allergy Drug Discovery, 13, 134-143.
Li, J., Wang, H., Wang, R., & Zhang, L. (2017). Giardia duodenalis infections in humans and other animals in China. Frontier in Microbiology, 8(2004), 1-14. Web.