Chagas, Malaria & Cryptosporidiosis: Causes and Care

Chagas, Malaria & Cryptosporidiosis: Causes and Care

Chagas Disease: Etiologic Agent and Vector

Chagas disease: etiologic agent Trypanosoma cruzi. The vector is the blood-sucking triatomine insect (triatomine). In the insect intestine the parasite develops juvenile stages such as epimastigotes and trypomastigotes. It is transmitted through vector feces.

Human Infection and Life Stages

In humans, trypomastigotes circulate in the bloodstream, invade cells, and can be found as intracellular amastigotes that affect cells and tissues.

Clinical Manifestations

Clinical manifestations: general deterioration, dyspnea, headache, and lower extremity edema. There is an indeterminate or asymptomatic period that can last 20 to 30 years or more. Diagnosis is made by blood tests.

Chronic Phase

Chronic phase affects the nervous system, digestive organs, and the heart.

Prevention

Prevention: in areas not endemic, ventilate the house. If the area is already infected, clean and reduce vector habitats where the insects live.

Treatment

Treatment: medications are used when symptoms first start (at disease onset).

Malaria: Etiology, Vector, and Distribution

Malaria: etiologic agent Plasmodium; vector: Anopheles mosquito. Distribution includes poorer areas in Asia, Africa, and South America (including the Amazon).

Lifecycle

Lifecycle: the parasite cycles partly in the mosquito and partly in humans. There are asexual stages in the mosquito and human; juvenile forms precede liver invasion, where parasites mature before entering the bloodstream.

Symptoms and Severity

Symptoms: chills, fever and sweating, and muscle discomfort. Malaria can be deadly.

Mild forms can often be treated with standard regimens; severe malaria is more dangerous and limits treatment options.

Prevention

Prevention: partial immunity may develop in people living in endemic areas. Prophylactic and preventive measures include:

• Antimalarial prophylaxis where recommended: mefloquine, doxycycline, chloroquine
• Avoiding mosquito bites: wear clothing that covers arms and legs, use window screens, and apply insect repellent

Treatment

Treatment (uncomplicated): quinine sulphate 10 mg salt/kg every 8 hours; plus doxycycline 100 mg daily for 7 days.

Treatment (severe malaria): quinine dihydrochloride 20 mg salt/kg base given intravenously in 5% dextrose or normal saline, infusion over 4 hours.

Cryptosporidiosis: Agent, Transmission, and Reservoirs

Cryptosporidiosis: caused by protozoa of the genus Cryptosporidium. The infectious form is the oocyst. Reservoirs include humans and animals.

Transmission

Transmission occurs by swallowing water contaminated with Cryptosporidium oocysts.

Risk Groups and Symptoms

Risk group: people with low defenses—immunocompromised individuals—are at higher risk. Clinical symptoms include diarrhea, watery stools, stomach pain, and mild fever.

Prevention

Prevention: thoroughly wash hands and avoid drinking untreated water.

Treatment

Treatment depends on the patient’s general condition, drug tolerance, and how advanced the disease is.