Introduction             Giardia lamblia which is also known as Giardia duodenalis and Lamblia intestinalis, is a common parasitic pathogen which infects intestines causing giardiasis in mainly in humans and other animals which includes cows, birds, cats, deer and many more

Introduction

            Giardia lamblia which is also known as Giardia duodenalis and Lamblia intestinalis, is a common parasitic pathogen which infects intestines causing giardiasis in mainly in humans and other animals which includes cows, birds, cats, deer and many more.

Type of microbe

            Giardia lamblia is a parasitic microorganism with flagella which colonizes reproducing in small intestine that results in causing diarrheal condition that is known as giardiasis (Cernikova, Faso & Hehl, 2018). Giardia lamblia attaches to epithelium with the help of sucker or a ventral adhesive disc. It reproduces by binary fission method.

Disease caused

            Giardiasis is a disease caused by the infection of Giardia lamblia in the small intestine. It is a common parasitic disease in humans worldwide (Dunn & Juergens, 2021). The cystic form of Giardia lamblia is infectious and in host it transforms to trophozoites form. These attaches to walls of the intestine and then replicates in the gut area.

Discovery

            Vilém Lambl first described the trophozoites of Giardia lamblia in 1859 isolated from the stool of a patient which he named Cercomonas intestinali, although Antonie van Leuwenhoek described “animalcules” that resembles Giardia in a letter written to Robert Hooke.  Raphaël Blanchard  in the year 1888, renamed it as Lamblia intestinalis in the honor of Vilém Lambl.

Signs and symptoms

            Most of the patient are asymptomatic, although severe symptoms can be observed in some cases. These symptoms includes severe diarrhea along with poor nutrient absorption. The symptoms appear after 9-15 days of infection but can also develop within one day as well Adam, 2020). Chronic diarrhea is a most common as well as prominent symptom associated with abdominal cramps, vomiting and nausea.

Transmission

            Fecal-oral transmission is the main transmission mode of Giardia lamblia, associated with the ingestion of the cystic stage of the parasite. The primary route of transmission includes personal contact, contaminated food and water (Harun, Sennang & Rusli., 2019). The cystic phage of the pathogen can survive its infectious capability in cold water.

Course

            Giardia lamblia show two phase in its infection cycle which includes the trophozoites stage which remains in small intestine freely and the cyst stage that is passed to environment with no intermediate host (Dixon, 2021)

Virulence factor

            The Cathepsin B is the confirmed virulence factor as well as the secreted protein that degrades the IL-8 inhibiting the chemotaxis of neutrophils. The exposure to the secreted host factors up the regulated Cathepsin B and cystatin which is a protease inhibitor of the cathepsins.

Laboratory diagnosis

            Giardiasis can be diagnosed in laboratory by identification of the cysts or the trophozoites in fecal samples of the infected patient (Hooshyar et al., 2019). The direct mount and concentration procedures are used for the identification process.

Treatment

            Different antibiotics can be used for the treatment of Giardia lamblia which includes, metronidazole being the most commonly used drug against it (Díaz, 2017). Other drug includes Tinidazole, Nitazoxanide. Paramomycin, furazolidone can also be used for the treatment process.

Prevention

            Maintenance personal hygiene is one of the major preventive measure that must be maintained to reduce the chances of the infection. Proper cleaning of hands, utensils, fruits and vegetables before cooking is to be done

Sequelae

            The sequelae that are associated with giardiasis are chronic fatigue, irritable bowel syndrome, cognitive impairment and extra intestinal manifestations.