What is Giardiasis?

Giardiasis is an intestinal infection that is caused by a parasite known as Giardia Lamblia or Giardia Intestinalis. This is an infection that is found worldwide especially in developing countries where poor sanitation and contaminated water sources are prevalent issues. Now it can affect people of all age groups, but is seen more commonly in children.

How infection occurs?
How does this infection occur? Now, the parasite exists in two forms, what we call the trophozoites and the cysts. The cysts are infectious forms as they have a protective shell and when they are shed in the stools of an infected individual or animal., they can survive for a long period of time out of the body in soil, water and food. The trophozoites are released from the cysts upon ingestion where they invade the intestine and produce the symptoms of giardiasis. Considering their ability to survive out of the body, they can be spread by water contamination, food contamination and person to person transmission.

Transmission via water and food
Now, the transmission via water can happen when the sources of water contaminated by the feces of infected people or animals can be lakes and streams where campers and hikers may consume it, municipal water supply, which is inadequately sanitized or contaminated with sewage, swimming pools and recreational water parks where there is accidental adulteration by people with diarrhea or babies in diapers, some well water in rural and lower socioeconomic areas which are improperly stored and untreated.
Now, in the transmitted via food – when there is consumption of improperly cooked food, which may not destroy the parasite if present, ready to eat raw food which is washed with contaminated water or if the food is handled by an infected person especially with improperly washed hands.

Person-person transmission
In the transmitted from person to person, when an infected individual does not wash his/her hands thoroughly after toilet use then they can leave behind the cyst on the surfaces of things or in food that they handle henceforth putting the other people around them at risk of picking up the infection. Now, the individuals or groups at risk of getting this infection include – caregivers changing diapers of infected individuals, child care setting and family members of an infected person.

In terms of symptoms, some people infected with this parasite may have no symptoms and the infection can resolve on its own. Other may show some of the following symptoms anywhere between 1-4 weeks after ingestion of the cysts. The symptoms include – stools can be bulky, greasy, frothy and foul smelling, there can be episodes of watery diarrhea with abdominal pain, there can be abdominal distension and gaseousness, there can be loss of appetite, there can also be lactose intolerance and malabsorption which can lead to weight loss, anemia and failure to thrive.

Diagnosis can be made by examining the stool sample, preferably a fresh sample, for ova and parasite, but it may be difficult to pick up in a single sample, and hence your doctor may advise you to give 3 samples in 3 different days. If your child has symptoms of giardiasis and it is not evident on stool test, then further investigations may be recommended like an endoscopy.

Your doctor may prescribe an antibiotic for symptomatic patients and for those who are not symptomatic but are at risk for transmission like day care workers, food handlers etc. Depending on the type of antibiotic or antiparisitic prescribed, it may be taken either as a single dose or for 5-7 days. Now, dehydration and electrolyte imbalance should be corrected using measures as we have mentioned in the topic of “gastroenteritis and dehydration”. Now, many patients with giardiasis become temporarily lactose intolerant that is they are unable to digest the sugar called lactose, which is found in dairy products and hence need to be on a lactose free diet for a few weeks.

Here are some of the things we can do to prevent the occurrence and spread of this illness. We can maintain good personal hygiene and improvise our sanitation methods. Thorough hand washing needs to be practiced after toilet use, after changing diapers, before eating and food handling. Use adequately filtered water for drinking and cooking purpose. Campers and hikers must avoid drinking from streams and lakes; drinking water must be adequately boiled before consumption. Avoid accidental ingestion or swallowing water from pools and water parks. Proper chlorination and maintenance of water distribution systems. And avoid eating food that is improperly cooked.
Team Ovum Hospitals