CHAMELEON BIOPSY RESULT: FILARIASIS
Filariasis in general
Filariasis is caused by various filarial worms (such as Wuchereria bancrofti, Brugia malayi, and Loa loa in humans; Foleyella atum and Acanthocheilonema spirocauda in chameleons), which are transmitted through the bites of infected mosquitoes.
Symptoms and Disease Manifestation: Filariasis symptoms can include "elephantiasis", a severe manifestation caused by the obstruction of lymphatic vessels, particularly in the terminal parts of the extremities, resulting in significant swelling and thickening of the skin and tissues. More frequently in chameleons, filarial worms are located subcutaneously (under the skin} or intraperitoneally (between the organs in the body cavity).
Mechanism of Disease: Filariasis involves obstruction of lymphatic vessels, leading to fluid accumulation and severe swelling. Chronic inflammation from the presence of the worms and their by-products contributes to symptoms.
Treatment Challenges: Treating filariasis in chameleons presents significant difficulties. Antiparasitic medications effective against the worms can be problematic because they may kill the parasites located in poorly vascularized areas, such as subcutaneous or intraperitoneal regions. These areas experience low blood and lymph flow, complicating treatment. The dead bodies of the killed worms can cause severe complications, including sepsis, which can ultimately lead to the death of the infected specimens.
Reinfection: In captivity, the reinfection is not a real risk. The parasite has a second host, blood sucking insects like some dipterans or mosquitos. These are not available in captivity, as they are usually very specific and home in the homeland of the chameleons. So, in captivity, the cycle gets disrupted.
Filariasis in Chameleons
Filariasis in chameleons is caused by parasitic nematodes, primarily Acanthocheilonema and Foleyella.
Clinical signs of filariasis in chameleons may include swelling or lesions on the skin, lethargy, weight loss, and potential secondary infections due to skin lesions. Diagnosis often involves identifying microfilariae in blood samples or examining tissue biopsies. Treatment typically includes antiparasitic medications, tailored to the severity of the infection and the species of nematode involved.
Acanthocheilonema spirocauda
has a life cycle that begins with adult worms residing in the tissues of the host, usually in the subcutaneous layers. These adults produce microfilariae, which enter the bloodstream of the chameleon. When a blood-feeding insect, such as a mosquito or biting fly, feeds on the infected chameleon, it ingests the microfilariae. Inside the insect vector, the microfilariae develop into infective larvae over time. When the infected insect bites another chameleon, it transmits the infective larvae, which migrate to the new host and mature into adult worms, repeating the cycle.
Foleyella atum
also infects chameleons and follows a similar life cycle. Adult Foleyella worms inhabit the subcutaneous tissues and lymphatic systems of their hosts. Female worms produce microfilariae that enter the bloodstream. These microfilariae are ingested by blood-sucking insects, which serve as intermediate hosts. Within the insect, the microfilariae develop into infective larvae, which are transmitted to new chameleon hosts when the infected insect feeds.
Good to know...
Saint Roch's Worm
In 2017, Italian researchers examined a 14th-century painting of Saint Roch, who was believed to cure the plague before contracting it himself. Unlike typical depictions featuring a bubo, this painting shows a wound on Saint Roch's leg oozing a long, white substance. Previously thought to be pus, researchers now suggest it represents a worm.
This may be the earliest illustration of the graphic parasite Dracunculus medinensis, or Guinea worm, which is ingested through contaminated water. After a year of incubation, the worm can grow up to 1 meter (about 3 feet) long and erupts painfully through the skin, causing intense suffering but is not usually fatal.
While no cases have been documented in Italy, the artist may have witnessed it firsthand, as Bari attracted many travelers from infected regions. Additionally, some speculate that the "fiery serpents" encountered by the Israelites during their exodus could have been Guinea worms, as they were common in the Middle East and victims reported severe burning sensations when the parasite emerged.