Parasitic Worms and Treatment

Parasitic worms that harm human beings are; protozoan parasites, helminth parasites, and ectoparasites. The distribution of parasitic infections is based on economic structure. Intestinal helminths and protozoan parasites are more common in developing countries. While in developed countries, protozoan parasites are responsible for gastrointestinal infections. 

What are protozoan parasites? 

Types, incidence, and treatment of parasitic protozoans

Protozoa are one-celled, microscopic organisms that are one- or six-celled and either live freely or as parasitic worms. They can multiply inside the host, which means their indication of causing disease spread. 

The transmission is through an oral-faecal route (through contaminated food & water,/person-to-person contact). Protozoa parasite spreads through the bite of a mosquito or fly, termed an arthropod vector. 

Protozoan parasites are divided into four groups. 

• Sarcodina – includes amoeba species like Entameba. 
• Mastigophora – includes flagellates species like giardia and leishmania 
• Ciliophora – includes ciliates like balantidium 
• Sporozoa –  includes organisms whose adult age is immobile

All four classes of protozoa are parasitic worms and can cause diarrhoea. Giardia. Intestinalis is the most common form of protozoan parasitic infection. Amoebiasis is the third leading cause of death worldwide, with the most significant impact being in developed countries. 

Cryptosporidiosis is fast becoming the common cause of infection, especially in HIV-positive patients and children under five. C.cayetanensis has been the recent cause of diarrhoea in the last decade. 

Antiprotozoal drugs 

1. Antimalarials 

Chloroquine is the drug of choice for malaria caused by all Plasmodium species except P. falciparum. P. falciparum is resistant to chloroquine. Drugs like amodiaquine and artesunate are used when chloroquine does not work. Primaquine, mefloquine, atovaquone-proguanil, and doxycycline are used as chemoprophylaxis treatments.

2. Antibabesial agents 

It is similar to malaria. If the disease is severe, the drugs used are atovaquone, azithromycin, clindamycin, and quinine. These drugs are used in tick-bites.

3. Antiamebic agents 

These drugs are used to treat amebiasis. The infection may be with or without symptoms and decides treatment. These are classified as, 

1. Luminal amebicides examples: iodoquinol, paromomycin sulphate, diloxanide furoate, 
2. Tissue amebicides 
3. Systemic amebicides examples: metronidazole, tinidazole and emetine 
4. Mixed amebicides examples include metronidazole, and tinidazole is used as mixed amebicides too.

4. Antigiardial agents 

These are the drugs used to treat giardiasis. The primary drug to treat is metronidazole; alternative drugs are albendazole and tinidazole.

5. Antileishmanial drugs 

These drugs treat leishmaniasis, among the neglected tropical diseases(NTD). Sodium stibogluconate is the drug of choice for visceral and cutaneous leishmaniasis, meglumine antimoniate, pentamidine, and amphotericin B are other alternatives for leishmaniasis. 

6. Anti-toxoplasmic agents 

Toxoplasmosis is seen in patients who are immunocompromised. It causes congenital and central nervous system diseases. Sulfadiazine with pyrimethamine is the drug for the management of toxoplasmosis. 

What are helminth parasites? 

Types, incidence and treatment of helminth helminths.

Helminths are large & multicellular organisms which are visible to the naked eye in adult stages. Due to their size, they do not multiply inside the human body and can live as normal or disease-causing parasitic worms. 

There are three groups of helminths.

1. Flatworms/ Tapeworms include trematodes and cestodes
2. Thorny-headed worms 
3. Roundworms are also called nematodes 

The adult forms of acanthocephala (thorny headed worms) live in GIT. The roundworms live in subcutaneous tissue, the lymphatic system, GIT & Blood. The immature and larvae forms cause infections in various human body parts. Helminth infections are primarily seen in tropical and subtropical regions of developing countries. It is due to inadequate sanitation and water facilities. 

As per recent studies, A.lumbricoides can infect over one billion people, and hookworms affect 740 million people. Apart from the mentioned helminths, helminths do not contribute much towards infection/disease. Intestinal infections affect the physical & mental growth of children. Disturb education & ultimately affect the economic situation. 

1. Antihelminthic agents 

These drugs act as vermicides or vermifuges. The drugs are used based on the type of parasitic worms & chemical structure of the drug. They should have a broader therapeutic index to attack the parasite than the human body.

2. Anticestodal drugs 

The drugs included in this category are mainly praziquantel- it is used as a vermicide and against cestodes like taenia saginata and diphyllobothrium latum. Alternatively, niclosamide can be used for treatment. Albendazole is another broad-spectrum anthelmintic which is indicated. 

3. Antinematodal drugs 

The drugs which are included in this category are praziquantel. It is effective against trematodes and is the drug of choice for Schistosoma species and clonorchiasis sinensis infections. Alternate drugs include metrifonate and oxamniquine. 

Albendazole is a drug for treating infections caused by nematodes and infections like ascariasis, trichuriasis, hookworm & pinworm infections. Diethylcarbamazine is the first choice of medication for filariasis, loiasis and tropical eosinophilia. 

What are ectoparasites ? 

Types & treatment of ectoparasites

The parasitic worms which are included in this category are ticks, lice, and mites. All of these are parasitic worms.

1. Anti Scabies agents 

The drugs used for scabies management are lindane, benzyl benzoate, permethrin and ivermectin. These drugs are used to treat scabies, a highly contagious pruritic disease. The highest cure rates are oral ivermectin, permethrin, and topical ivermectin with synergised pyrethrin.

2. Pediculicides 

Head lice are the most common type of ectoparasite. The disease is managed by pyrethrins & permethrin. Due to a rise in resistance to infection with these drugs, alternative medicine like ivermectin & malathion is prescribed.

Conclusion

Parasitic worms and infections can cause a tremendous burden of disease. Parasitic infections range from small and easily treatable to complex diseases. Regular deworming is the best way to prevent parasitic infections and affects millions of people worldwide. The use of insecticides is another way of controlling the parasites. Avail teleconsultation from our expert doctors on our online pharmacy when you place an order for medicines, or you can also download our Truemeds app to do the same. Get branded as well as generic medicines by uploading your prescription on Truemeds. When placing an order for medicines online, you may save more money by selecting alternative or generic medicine advised by Truemed’s expert doctors. And also, save up to 72% on your purchase and get free home delivery pan India.

Frequently asked questions

Disclaimer – Truemeds’ sole intention is to ensure that customers have access to information that is accurate & trustworthy. However, the information here should not be used directly and it cannot act as a substitute for the advice of a doctor. The information provided is only to stay informed. The information on side effects, drug interactions or warnings, and alerts are not exhaustive. Please consult your doctor for the right advice on diseases & medication information.

References 

• https://www.britannica.com/list/uninvited-guests-the-7-worst-parasitic-worms
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2754014/
• https://www.cdc.gov/parasites/about.html
• https://www.ncbi.nlm.nih.gov/booksoeba/NBK544251/