Chagas Disease, Listeria, and Campylobacter: An Overview
Chagas Disease, Listeria, and Campylobacter
Chagas Disease
Chagas’ Disease: The etiologic agent is Trypanosoma cruzi. The vector is the blood-sucking triatomine insect. The juvenile stages are epimastigotes and trypomastigotes (intestine). Transmission occurs through feces. In humans, trypomastigotes and amastigotes affect cells and transmit through the bloodstream as trypomastigotes, primarily in rural areas to the north.
Clinical Manifestations
The acute phase takes 20 to 30 days, often with no signs or symptoms, but sometimes with fatigue, dyspnea, and headache. The indeterminate phase can last 20 to 30 years or more. The chronic phase often involves heart damage, diagnosed by blood tests. The chronic phase affects the digestive system and the heart.
Prevention
In non-endemic areas, ventilate the home. If already infected, clean the living area.
Treatment
Medications are used when the infection is first detected. Untreated, it can be fatal.
Natural Reservoir
Armadillos, marsupials, rodents, and bats are natural reservoirs, as well as dogs, cats, and guinea pigs.
Cycle
The infected insect vector (triatomine) bites uninfected humans, delivering trypomastigotes to cells near the bite. These enter cells and become amastigotes, reproducing by binary fission and exiting the cell as trypomastigotes, entering the bloodstream. A non-infected insect vector then bites the human, becoming infected with the trypomastigote. In the insect’s stomach, it becomes epimastigotes, multiplies, and then becomes trypomastigotes in the gut.
Listeria
Listeria is a Gram-positive, non-sporulating, facultative anaerobic bacillus that thrives in a wide range of temperatures (1-45°C).
Listeria monocytogenes
Listeria monocytogenes is optionally aerobic, lacks a capsule, and is pathogenic to humans. Its habitat includes soil and decomposing plant matter, making it a foodborne illness (ETA).
Infection
Infection occurs by consuming frozen foods, raw milk, or contaminated sewage. It enters the body through the digestive tract via food. A key feature is its ability to multiply in refrigerated foods.
Symptoms
Symptoms include fever, muscle pain, and gastrointestinal distress. If it spreads to the CNS, it can cause headache and loss of balance. The average incubation period is 3 weeks.
Risk Groups
Risk groups include pregnant women, newborns, and immunocompromised individuals.
Diagnosis
Diagnosis involves lab analysis of an organic sample.
Treatment
Treatment involves administering antibiotics such as penicillins.
Recommendations
Thoroughly wash hands, avoid cross-contamination, and eat well-cooked foods.
Campylobacter
Campylobacter (fetus, coli, lari) are non-sporulating, Gram-negative bacteria, spiral-shaped with a flagellum, microaerophilic, and develop at 37°C, with jejuni developing at least at 42°C.
Reservoir
Birds, pets, and wildlife serve as reservoirs.
Pathogenicity
Campylobacter jejuni is most associated with human diseases, invading the terminal ileum and colon.
Infection
Infection occurs by consuming unpasteurized milk, undercooked meats, or contaminated water.
Symptoms
Symptoms include fever, abdominal pain, and bloody diarrhea.
Diagnosis
Diagnosis involves direct examination via direct immunofluorescence and culture on blood agar.
Treatment
Treatment includes continued water intake for diarrhea and, in severe cases, antibiotics like erythromycin. Long-term consequences include arthritis and Guillain-Barre syndrome. Recovery typically takes 2 to 5 days. Risk groups include pregnant women, infants, the elderly, and immunocompromised individuals.