Context: In an exploratory study, the repurposed drug, an anthelmintic originally used to treat tapeworm infection, was found to show promising results in treating COVID-19.
- The study was undertaken by Bengaluru-based National Centre for Biological Sciences (NCBS-TIFR) and Institute for Stem Cell Science and Regenerative Medicine (InSTEM) along with Indian Institute of Integrative Medicine (CSIR-IIIM), Jammu.
- A long wait for drugs to treat COVID-19 may come to a close, if Phase II trials of the drug niclosamide deliver positive results.
- It is well known that the spike protein of the receptor binding domain attaches itself to the ACE2 receptor present in the cell. This is a route the virus uses to enter the cell.
- There is also another way (Alternative Route) of entering the cell, especially in cells that do not carry ACE2.
- The stomach and proximal intestinal epithelium have cells that do not carry the ACE2 receptor but also are infected by the virus
- The cell line on which currently these institutes work may be a surrogate model for such a system.
- To enter such cells the spike glycoprotein finds a different pathway using alternative binding proteins on the surface of the cell.
- These are not yet fully characterised.
- This other pathway is under research.
Blocking the Virus:
- When the virus tries to enter the cell, it is first engulfed in a membranous vesicle.
- This vesicle provides an environment of low pH (acidic medium) which is necessary for the virus to infect the cell.
- Thus, a substance that would alter the pH of the environment would block the entry of the virus.
- This role can be played by, for instance, niclosamide.
- It is a drug used for tapeworm treatment.
- Other worms, such as pinworms and roundworms, are not affected.
- It is taken orally so can be used right off the shelf if the dosage and efficacy is proved for Covid.
- Tapeworms are flat, segmented worms that live in the intestines of some animals.
- Animals can become infected with these parasites when grazing in pastures or drinking contaminated water.
- Eating undercooked meat from infected animals is the main cause of tapeworm infection in people.
- Although tapeworms in humans usually cause few symptoms and are easily treated.
- They can sometimes cause serious, life-threatening problems.
- Tapeworm Types:
- Six types of tapeworms are known to infect people.
- They are usually identified by the animals they come from -- for example;
- Taenia saginata from beef,
- Taenia solium from pork, and
- Diphyllobothrium latum from fish.
- Tapeworm causes:
- Tapeworms have a three-stage life cycle:
- An immature stage called a larva, and
- An adult stage at which the worm can produce more eggs.
- Because larvae can get into the muscles of their hosts, infection can occur when you eat raw or undercooked meat from an infected animal.
- It is also possible to contract pork tapeworms from foods prepared by an infected person.
- Because tapeworm eggs are passed with bowel movements.
- A person who doesn't wash hands well after wiping and then prepares food can contaminate the food.
- Tapeworm Symptoms
- Sometimes tapeworms cause symptoms such as:
- Abdominal pain,
- Hunger or loss of appetite,
- Weight loss and
- Vitamin and mineral deficiencies,
- In rare cases, tapeworms can lead to serious complications, including blocking the intestine, or smaller ducts in the intestine (like the bile duct or pancreatic duct).
- If pork tapeworm larvae move out of the intestine, they can migrate to other parts of the body and cause damage to the liver, eyes, heart, and brain.
- These infections can be life-threatening.
- Seizures are the most common symptom.
- Treatment for Tapeworms
- The type and length of treatment may depend on the type of tapeworm.
- Tapeworms are usually treated with a medicine taken by mouth.
- The most commonly used medicine for tapeworms is praziquantel (Biltricide).
- Preventing Tapeworms in Humans
- Avoid raw fish and meat.
- Thoroughly cook meat to temperatures of at least 145 degrees Fahrenheit for whole cuts of meat and to at least 160 degrees F for ground meat and poultry.
- Then, allow the meat to rest for three minutes before carving or consuming;
- The heat continues killing pathogens during that time.
- Freezing meat to -4 degrees F for at least 24 hours also kills tapeworm eggs.
- When traveling in undeveloped countries, cook fruits and vegetables with boiled or chemically-treated water before eating.
- Wash hands with soap and hot water before preparing or eating foods.