Parasitic Diseases: A Global Health Issue

Parasitic Diseases: A Global Health Issue

Parasitic diseases are a global health problem, affecting human health and development. They are caused by parasitic pathogens, including protozoa, helminths, fungi, and arthropods.

Differences between parasitic diseases and bacterial, viral, and fungal diseases:

• Bacterial, viral, and fungal diseases: Usually cause acute illnesses with high virulence and the potential to be fatal. These pathogens multiply rapidly, creating large numbers in the host’s body.

• Parasitic diseases: Often have a silent progression and are difficult to detect. Parasitic pathogens reproduce more slowly, produce fewer numbers, and are easily transferred to a chronic state. Parasitic diseases are also easily reinfected.

The immune system and parasitic diseases:

The body’s immune system against parasitic diseases is often weak and unstable.

Main syndromes of parasitic diseases:

• Inflammation: Occurs at the site of parasitic invasion or parasitism, for example, hookworms cause dermatitis, Trichomonas vaginalis causes vaginitis.

• Nutrient loss: Parasites take nutrients and food from the host, leading to nutrient loss for the body.

• Intoxication: Parasites release metabolic products and toxic excretions into the body. The intoxication can be acute or chronic.

• Allergy: Occurs frequently, manifested by itching, rash, and eosinophilia.

Antigens and immunity:

Parasite antigens are often specific to the host and stimulate the corresponding immune system.

Immune system:

The body responds to parasites by two mechanisms:

• Cellular immunity: Specialized cells are mobilized to capture and destroy parasites.

• Humoral immunity: Antibodies are produced to fix and destroy parasites.

Factors of disease transmission:

• Source of disease: Place where pathogens are present and can be transmitted to humans. Diseases caused by parasitic animals (zoonotic) are transmitted from wild animals or pets.

• Disease-transmitting organisms (vectors): Organisms such as mosquitoes, lice, ticks,… can transmit diseases from animals or sick people to healthy people.

• Elimination route: Pathogens are excreted from the body through waste products such as urine, feces, sputum, blood, secretions, or through the skin.

• Entry route: Pathogens enter the body through the digestive, respiratory, reproductive, blood, or skin routes.

Bodies susceptible to disease:

The susceptibility to infection depends on many factors, including:

• Immunity

• Occupation

• Age

• Gender…

Disease distribution:

The distribution of parasitic diseases depends on factors such as:

• Climate: High temperatures and low humidity can destroy parasite cells, while high temperatures and humidity create favorable conditions for them to thrive.

• Intermediate hosts: The presence of intermediate hosts can affect the spread of the disease.

• Host habits: Habits such as personal hygiene, contact with animals, diet,… can increase the risk of infection.

Diagnosis:

Diagnosing parasitic diseases is often difficult because the disease often progresses silently and has vague symptoms.

Diagnostic methods:

• Direct examination: Directly detect parasites in samples.

• Culture: Increase the number of parasites for easy detection.

• Serology: Detect antibodies or antigens in the blood.

• Endoscopy: Directly observe lesions in the body.

• X-ray: Detect lesions in organs.

Parasitic diseases are a serious health problem. Raising awareness of the disease, implementing preventive measures and timely treatment is essential to control and limit the impact of the disease on human health.