Paragonimiasis

Transmission is caused by eating raw, salted, pickled, or partially cooked freshwater crabs or crayfish (crawfish) with infectious larvae (metacercariae). The larvae are released when the crab or crayfish is digested, and they migrate within the body. Most often the larvae end up in the lungs. Ingesting raw meat from other infected vertebrae hosts that contain young flukes (e.g., wild boars) can also cause infection. Contaminated utensils, such as knives or cutting boards, can also spread the infection. Infection is not transmitted directly from person to person.

Initial signs and symptoms may be diarrhea and abdominal pain, followed several days later by fever, chest pain, and fatigue. The symptoms may include a dry cough, which later becomes painful. Cough may produce rusty-colored or blood-tinged sputum on exertion, and pleuritic chest pain. Extrapulmonary disease is not uncommon, with flukes found in such sites as the CNS, subcutaneous tissues, intestinal wall, peritoneal cavity, liver, lymph nodes and genitourinary tract.

Infection usually lasts for years, and the infected person may be asymptomatic. The symptoms of paragonimiasis can be similar to those of tuberculosis, clinically and on chest X-rays.

• Routine hand washing with soap and warm water.
• Never eat raw freshwater crabs or crayfish. Cook crabs and crayfish to at least 145°F (~63°C).
• Travelers should be advised to avoid traditional meals containing undercooked freshwater crustaceans.

Investigation Guidance | Texas DSHS

Paragonimiasis became a notifiable condition in Texas in 2016. There have been no cases reported in Texas from 2016 through 2020.

Report Paragonimiasis within 1 week to the local or regional health department or the Texas Department of State Health Services (DSHS), Emerging and Acute Infectious Disease Branch (EAIDB) at 800-252-8239 or 512-776-7676.

Reports from healthcare providers and laboratories may be submitted using the EPI-2 Initial Provider Disease Report Form.