Puerto Rico is poised to become the first U.S. territory to eliminate schistosomiasis, a parasitic disease impacting vulnerable populations for generations. A decades-long effort, bolstered by a recent collaborative initiative with the Pan American Health Institution and University of New Mexico researchers, is now in its final stages of verification. The program focuses on monitoring freshwater snails-the key vector for transmission-and represents a significant step forward in addressing neglected tropical diseases affecting the Caribbean and beyond.
Public health officials in Puerto Rico are on the verge of eliminating schistosomiasis, a chronic parasitic disease that has plagued the island and other tropical regions for centuries, thanks to a collaborative monitoring effort focused on freshwater snails.
The Pan American Health Organization (PAHO) is partnering with scientists from the University of New Mexico and Puerto Rican public health experts to track the snails, which serve as an intermediate host for the parasitic flatworm that causes schistosomiasis, also known as bilharzia. This work is crucial because parasitic diseases disproportionately affect rural and impoverished communities, contributing to cycles of poverty and disability.
Schistosomiasis can manifest with acute symptoms like itchy rashes, fever, chills, abdominal pain, diarrhea, and blood in the urine or stool. Chronic infections can lead to severe complications, including enlarged livers and spleens, anemia, fibrosis, stunted growth in children, reduced productivity, and, rarely, neurological problems or infertility.
Recently, approximately 30 local public health workers received training, supported by PAHO, on identifying, collecting, and preserving snails for analysis. Teams surveyed around 115 lakes and streams across five regions of Puerto Rico.
“We are on the cusp of being able to say that we have eliminated one of the most important neglected tropical diseases in the world in the Caribbean region, where it has historically had a negative impact on public health,” explained Eric Loker, professor emeritus of parasitology at the University of New Mexico.
The collected snails are now being analyzed in the University of New Mexico’s laboratory, where scientists are employing advanced diagnostic tools – including high-precision molecular tests like PCR, environmental DNA analysis, and biosensors – to accurately detect and monitor transmission. This detailed monitoring is essential for verifying the elimination of the disease.
The training aims to strengthen Puerto Rico’s capacity to monitor potential transmission sites and support the ongoing verification of schistosomiasis elimination on the island. Continued surveillance will be key to preventing re-emergence.
“If we are able to document the elimination of schistosomiasis in Puerto Rico, and I believe we will, it will be like closing a cycle,” said Puerto Rico Secretary of Health, Dr. Víctor Ramos. “Once the disease is eliminated, I think it will be a tribute to the great work of many doctors, researchers, and professionals.”
