Ascaris life cycle - Symptoms & Types

Ascaris lumbricoides is a parasitic nematode roundworm that infects the intestines of humans. It is one of the largest and most prevalent intestinal parasites.

Ascaris lumbricoides is an important roundworm because it causes a serious human health problem called ascariasis. It causes malnutrition and stunted growth, alongside other serious health complications, especially in children. In tropical and subtropical areas, Ascaris infects about 1.2 billion people worldwide, especially in areas with bad and unsanitary hygiene practices.

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This Story also Contains

1. Taxonomic Classification
2. Physical Characteristics
3. Life Cycle Of Ascaris lumbricoides
4. Pathogenesis
5. Preventative Measures
6. Recommended Video On Ascaris Lumbricoids

Taxonomic Classification

• Kingdom: Animalia

• Phylum: Nematoda

• Class: Secernentea

• Order: Ascaridida

• Family: Ascarididae

• Genus: Ascaris

• Species: A. lumbricoides

Physical Characteristics

• The adult Ascaris worms are cylindrical with a smooth, striated cuticle. The male measures 15-31 cm, while the female is a bit longer at 20-49 cm.

• Males are smaller, with the posterior end of the body curved, while females are straight. Males possess spicules used in copulation.

Diagram Of Ascaris Lumbricoides

The diagram given below shows the structural difference between the male and female body structure of Ascaris Lumbricoidis.

Life Cycle Of Ascaris lumbricoides

There are many stages in the life cycle of ascaris :

Ingestion

This worm's eggs are not contagious until they come into touch with soil. Someone can contract the virus through the soil vegetable or any other manner if they come into contact with such contaminated soil by eating any fruit or vegetable that was growing in it.

Migration

The second stage of the ascaris life cycle is referred to as migration. Migration is the process by which the egg enters the organ.

Once the eggs have hatched, they move into the small intestine where the larva stage is being produced. With the assistance of the small intestine's intestinal wall, they now begin to enter the lungs.

Maturation

These larvae reach their maturation stage when they are ingested by a human. Now, these larvae return to the small intestine where they grow into either the male or female ascaris worm. Male worms are often shorter than female worms, which average about 15 inches in length.

Reproduction

As a final step, human reproduction now takes place in the small intestine. Each day, female ascaris worms release into the human body roughly 2 lakh eggs.

The fertilized egg remains in the soil for at least 18 days before becoming infected. At this point, the egg's larva is excreted out through human faeces.

The entire procedure of this reproduction takes about 3 months.

Diagram Of The Life Cycle Of Ascaris lumbricoides

Pathogenesis

• Ascaris lumbricoides are transmitted via the faecal-oral route; that is, mono-infection ensues on ingesting food or water contaminated by faeces from the eggs.

• These include poor sanitation, lack of clean water, and residence in endemic areas.

• Abdominal pain, nausea, emesis, and low-grade fever may be present.

• Serious stage may lead to intestinal blockage, malnutrition, and growth retardation in children.

• This may lead to larval migration with pulmonary complications like pneumonitis and, occasionally, liver or pancreatic involvement.

Symptoms of Ascariasis

There are two different types of ascariasis:

Intestinal Ascariasis

• There are many different symptoms of this type of ascariasis, including vomiting and gas.

• Symptoms also include weight loss and diarrhoea.

• Malabsorption of food can also be observed in this type of ascariasis.

• Sometimes it is also observed that growth retardation occurs as well. Nausea is the main symptom that is followed in this type of ascariasis.

Pulmonary Ascariasis

• In this type of ascariasis fever that is persistently high is one of the major symptoms that can be seen within a few hours of infection.

Mode Of Infection Of Ascaris Lumbricoides

Infection occurs by swallowing fully developed Ascaris eggs covered with shells. These eggs are consumed with raw vegetables and by drinking water contaminated with roundworms. This worm can go straight to the mouth with the dirty fingers dipped in the soil. The risk of ascariasis is observed more often in children than in adults. The infection takes place through contaminated food, uncooked food and raw food. It can also be spread through canned food.

Incubation Period Of Ascaris Lumbricoides

It takes Ascaris lumbricoides between 60 and 75 days to infect a man. This incubation period begins at the point of infection exposure and lasts until the mature female lays her eggs and symptoms can be seen. This is the time when it multiplies and causes disease.

Preventative Measures

• Importance of hand washing, clean water for washing, and food washing.

• Mass deworming programs at the school or community level could make a difference in reducing prevalence.

• Infections can be prevented through raising awareness about hygiene and sanitation.

Among the most important parasitic nematodes causing high disease burden, particularly in children in endemic areas, is Ascaris lumbricoides. The diagnosis, treatment, and prevention of the infection require an awareness of its life cycle, transmission, and clinical manifestations. There is a continuous need for research into improved treatments and vaccines against these infections. Public health initiatives are major tools in reducing the global burden of ascariasis.

Future efforts need to concentrate on ensuring better and sustainable sanitation facilities, promoting education, and developing new antihelminthic drugs and vaccines against Ascaris lumbricoides for effective control.

Recommended Video On Ascaris Lumbricoids