Predatory worms or segmented parasites is what leeches are. They are closely related to earthworms and as such, they also have muscular but soft yet segmented body parts that can contract and stretch.
They live on land, in water and suck blood from frogs, lizards, fish, and birds. If they get the chance anyway, they could feed on humans. They may have been helpful to circulate blood in man as well. By the way, naming fish alone does not limit their host to just fish in the sea world.
However, in the sea world, there has been a relentless effort at discovering the cause of a major turtle disease in the sea. A disease better known as FP makes sea turtles develop tumours all over their bodies. This limits their level of mobility – and circumstantially, their health. This is because, they will not be able to catch a prey – swinging the door open for hunger to me in.
Over the last three decades, Florida is reportedly one of the most heavily affected areas by FP. One of the highest rates ever documented was related from the Indian River Lagoon where approximately, half the green juvenile turtles have the tumours.
Although the exact cause of this disease is yet to be discovered, many weak fingers point at saltwater leeches. They are made suspects because of how frequent their presence is in areas where sea turtles that contracted FP tumours are often found. These areas often include their mouth, eyes and flippers.
Sea turtles are all categorized as endangered by threats of coastal development, pollution, fishing and in fact, infectious diseases. The knowledge of whether leeches play a role in the transmission of diseases can help in better predicting the spread of FP and aid a better understanding of the disease itself. And more likely, inform a decision to remove all leeches from rehabilitation centres built for sea turtles.
In a bid to find out the possibly existing connection between FP and leeches, researchers made green and loggerhead turtles the case study. A documentation was made of the leeches found present on both kinds of turtles captured from Indian River Lagoon.
The experiment was made to know which turtle(s) had the virus with the most likely reaction responsible for disease development on each individual turtle.
The result revealed that leech parasitism made more waves in the green turtles. The same cannot be said for loggerhead turtles and the sub specie returned unharmed or better said, void of such virus. This virus is ChHV5.
During genetic analysis, one-fifth leeches returned positive for ChHV5. Only one leech specie however trended towards FP positive. This further supports the hypothesis which argues that leeches act as ChHV5 transmitters rather than as the dominant cause of FP on sea turtles.
After a considerable thread – however thin – has been established between leeches and FP, researchers would want to get more specific by looking into whether leeches also transmit what is called turtle herpesvirus, which would provide an unbendable evidence that FP is caused by this underlying virus.