Imagine you are on vacation in Hawaii. You decide to go surfing bright and early one morning. You don your wetsuit and board out into the ocean and the morning sun crests the horizon. As you drift slowly in the swells, you look down at the vibrant coral reef beneath your feet. During your contemplations and observations, you notice a green sea turtle slowly meander its way over to you. As the shelled animal slips closer to you, you notice it has some odd growths on its head and face. Large, discolored tumors are growing all over this poor sea creature; this animal has the disease fibropapillomatosis (FP).
FP was originally diagnosed in sea turtle populations in Key West, Florida. Total prevalence of FP in all sea turtle populations reached between 50% and 70% in the 1990’s. The highest recorded prevalence was 92% in Kaneohe Bay, Oahu, Hawaii. Cases of FP are generally more frequent in warmer waters with prevalence of FP in the Caribbean, Hawaii, Japan, and Australia reaching similar numbers as total populations in the 90’s. It is transmitted horizontally, most likely to be through direct contact between and infected individual and an uninfected individual.
FP is characterized by benign tumors that grow on the face, tail and flippers of the affected sea turtles. The suspected cause of FP is a herpes virus. This cannot be proven but is commonly found (95% – 100% of the time) on the tumors of the affected turtles. Persistent organic pollutants were expected to be amplifying the effects of the disease or to suppress the immune systems of uninfected individuals. This was suspected because there was a rise and fall of FP cases that was consistent with the rise and fall of levels of persistent organic pollutants. A recent study found that the persistent organic pollutants were not correlated with triggering FP because the levels of persistent organic pollutants did not increase with the severity or the prevalence of FP in turtle populations. It did find that persistent organic pollutants possibly exacerbated the effects of the disease in the later stages of its life cycle.