Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at August 28, 2016

Rhinosporidiosis is a localized and chronic parasitic infection that persists in a patient for decades. It is caused by Rhinosporidium seeberi, a parasitic protist and involves a tumorous inflammation that occurs in the mucous membranes in the head and body. Only on rare occasions has this infection been life-threatening.


Definition & Facts

Rhinosporidiosis was thought to be a fungal infection when it was first observed by Dr. Malbran in 1892. It was described by the Argentine physician Guillermo Seeber in 1900. Dr. Seeber observed the infection first in a 19 year old Argentinian farmhand.

New RNA testing has proven that this infection is not caused by a water mold (fungus) as originally classified. Rather, it is a quickly maturing microbe that causes fleshy, easily torn polyps to grow on the soft, wet areas of the body as it attacks its host.

This infection is unusual in that there is much that remains unknown about the originating species - Rhinosporidium seeberi - though it ultimately affects both humans and other animals in the same way. The life-cycle of the organism is unknown, though it is known that it attacks fish and amphibian species that live in or around contaminated freshwater.

This parasite is commonly found in warm and moist tropical environments such as in several countries in South America, southeastern Asia, southern India and Sri Lanka. It prefers stagnant freshwater though some evidence exists that it may also be air-born. This infection has been documented in the United States for 60 years in Florida, Georgia, as well as Texas and other southwestern states. The infection tends to be more common in the winter than at any other time of year.

R. seeberi tends to attack males at a three times higher rate than females. Race has no bearing on infection rates. Documented rhinosporidiosis cases affect people aging from 15 years to 40 years old. People who experience the infection in their eyes tend to fall between 11 and 20.

Symptoms & Complaints

Rhinosporidiosis presents in the patient as red or pinkish colored wart-like polyps growing in or on the mucous membranes, such as in the conjunctiva of the eye, the thin skin of the mouth, or the urethra. It can cause nosebleeds and blockages of the nasal passages as well as secondary infection in the mucosal tissues.

This infection should be suspected if a patient complains of a blocked feeling in their nasal passages and they have a history of being near any stagnant or polluted waterways for even a short amount of time.

Symptoms of this infection may also include a wet cough, inflammation of the mucous membranes in the nasal passages, localized itching, and profuse amounts of nasal discharge.

Blocked tear ducts and light sensitivity of a patient's infected eye may occur as well. Other bacterial infections may be present alongside rhinosporidiosis and may be directly caused by it as the polyps tear and bleed easily.

Patients with rhinosporidiosis of the genitals or urethra present with similar tumors. Vital organs have been affected in less than one percent of the known cases.


R. seeberi prefers hosts that live in polluted waterways such as rivers, lakes and ponds. Most patients infected with rhinosporidiosis have come into contact with contaminated water. The infection is often spread through the body openings, such as when swimming or drinking.

With the advent of RNA testing, researchers have described R. seeberi as a type of protist instead of a fungus; they placed into its own class, mesomycetozoea with other fish and amphibian parasites, though some researchers maintain it's a type of cyanobacteria.

Rhinosporidiosis is not caused by genetic factors, and people do not transmit or pass it onto one another. It has been noted in most common pets and livestock, as well as birds such as swans and parrots.

Diagnosis & Tests

Most of the commonly used medical fungal stains will identify R. seeberi. A patient's doctor may order a biopsy of infected tissue as rhinosporidiosis may present as different symptoms in separate individuals.

The parasite's primary means of reproduction is through spores. These spores may be visible in the wart-like polyps that are a clear symptom of this infection, marking the line between the diagnosis of a fungal infection and a parasitic infection.

Treatment & Therapy

Surgically removing the tumors from an infected patient then cauterizing the wound is the only way to rid the host of this parasite. Researchers have not figured out a way to grow R. seeberi in a lab culture, so there are no specific antibiotics or vaccines available to treat rhinosporidiosis.

Prevention & Prophylaxis

Education and avoidance are the primary ways to reduce both human and animal infection. First, educating people about microbes and their life cycles as well as encouraging less pollution in general will cut down on the number of Rhinosporidiosis cases seen worldwide.

Secondly, limiting construction or public works projections that will either result in or require large containers or reservoirs of standing water should cut down on the ability for the parasites to reproduce.

A third preventative measure would be to identify and record infected ponds, lakes, streams and drinking water.

Lastly, designing and implementing a test to analyze specifically for the microbe R. seeberi in regions where Rhinosporidiosis is commonly known would allow medical researchers and biologists a better chance in understanding the parasite and its life cycle.