+1 (629)348-3199Rapid Communication - Journal of Parasitic Diseases: Diagnosis and Therapy (2025) Volume 10, Issue 2
Protozoan Infections: Causes, Symptoms, and Treatment
Pascal Boireau*
Drugs for Neglected Diseases initiative (DNDi), Switzerland
- Corresponding Author:
- Pascal Boireau
ANSES (French Agency for Food, Environmental and Occupational Health & Safety), University of Paris-Est, France
E-mail: pascal.boireau@anses.fr
Received: 02-Apr-2024, Manuscript No. AAPDDT-25-166441; Editor assigned: 03-Apr-2024, AAPDDT-25-166441(PQ); Reviewed: 01-Apr-2024, QC No. AAPDDT-25-166441; Revised: 14-Apr-2024, Manuscript No. AAPDDT-25-166441 (R); Published: 22-Apr-2024, DOI:10.35841/2591-7846.10.2.219
Citation: Boireau P. Protozoan Infections: Causes, Symptoms, and Treatment, J Parasit Dis Diagn Ther. 2025; 10(2):219
Introduction
Protozoan infections are diseases caused by protozoa, which are single-celled eukaryotic organisms found in various environments including soil, water, and as parasites in animals and humans. These infections represent a significant global health concern, causing a range of illnesses from mild gastrointestinal distress to life-threatening conditions such as malaria and African sleeping sickness What Are Protozoan Infections? Protozoa are microscopic organisms that can move and reproduce within the host. They belong to diverse groups and are responsible for several parasitic diseases affecting humans and animals. Protozoan infections are typically transmitted through contaminated water or food, insect vectors, or direct contact with infected individuals or surfaces [1, 2, 3, 4].
Common Protozoan Diseases and Their Transmission Malaria: Caused by Plasmodium species and transmitted by the bite of infected Anopheles mosquitoes. Symptoms include fever, chills, headache, and vomiting. It is a major cause of morbidity and mortality worldwide. Amoebiasis: Caused by Entamoeba histolytica, transmitted through contaminated food or water. It causes abdominal pain, diarrhea, and in severe cases, bloody diarrhea and colonic ulcerations. Giardiasis: Caused by Giardia lamblia, leading to diarrhea, abdominal cramps, and bloating, commonly transmitted via contaminated water or food. Toxoplasmosis: Caused by Toxoplasma gondii, acquired through undercooked meat or contact with cat feces. It can cause flu-like symptoms and is particularly dangerous for pregnant women and immunocompromised individuals [5, 6, 7].
Leishmaniasis caused by Leishmania species and transmitted by sandflies. It manifests as skin ulcers, fever, and systemic illness in severe cases. Trypanosomiasis: Includes African sleeping sickness and Chagas disease, caused by Trypanosoma species and transmitted by tsetse flies or triatomine bugs. Symptoms include fever, swollen lymph nodes, muscle pain, and can lead to severe cardiac and neurological complications. Cryptosporidiosis: Caused by Cryptosporidium, leading to watery diarrhea, especially severe in immunocompromised individuals. Transmission occurs via contaminated water or contact with infected persons. Naegleriasis: A rare but often fatal brain infection caused by Naegleria fowleri, contracted through inhalation of contaminated water. Symptoms of Protozoan Infections Symptoms vary depending on the protozoan species and affected organs but commonly include: Fever Diarrhea Abdominal pain Nausea and vomiting Fatigue and muscle aches Jaundice in some cases Severe infections can lead to organ failure, neurological impairment, and death Prevention and Control Preventing protozoan infections focuses on: Improving sanitation and personal hygiene to reduce fecaloral transmission Ensuring safe drinking water and food handling practices Controlling vectors such as mosquitoes, sandflies, and tsetse flies Using protective measures like insecticide-treated nets and repellents Public health education and surveillance Treatment of Protozoan Infections Treatment depends on the specific protozoan infection: Malaria: Treated with antimalarial drugs such as chloroquine, artemisinin-based combination therapies, and prophylactic medications for travellers [8, 9, 10].
Managed with metronidazole and sometimes antibiotics for severe cases. Treated with pyrimethamine and sulfadiazine, especially important for pregnant women and immunocompromised patients. Trypanosomiasis: Current treatments have limitations and side effects; however, new therapies targeting protozoan invasion mechanisms, such as antisense nucleic acid drugs against Trypanosoma cruzi, are under development to improve efficacy and reduce adverse effects. Other protozoan infections: Managed with specific antiprotozoal drugs such as metronidazole for giardiasis and trichomoniasis, and nitazoxanide for cryptosporidiosis.
Conclusion
Protozoan infections remain a major health challenge worldwide due to their diverse modes of transmission, complex life cycles, and ability to evade the immune system. Effective prevention through sanitation, vector control, and public health measures, combined with appropriate medical treatment, is essential to control these diseases. Advances in drug development, including novel molecular therapies, offer hope for improved management of protozoan infections in the future.
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