Stage number 4: Virology. I’m going to extract a part of the brain of this tilapia to examine if it is infected with the Tilapia Lake Virus (TiLV). I put a part of the brain inside alcohol and in a few steps we extract the genetic material of the brain to get to the RNA. At the end of the extraction I will put this test tube inside this device, which is a portable PCR where the genetic material taken from the Tilapia brain is extracted. After an hour I receive a positive or negative answer regarding the Tilapia Lake Virus. This is the last stage after we have done the quality of the water examined at the beginning we have also examined parasitology, bacteriology and finally virology to know what caused the disease of the fish.