Lonomia obliqua
Encyclopedia
Lonomia obliqua is a species of Saturniid moths from South America
. Its famous for its larvae form, rather than the adult moth, for several reasons. Recently announced in an episode of the Discovery Channel
, known as the “assassin caterpillar,” this caterpillar has a spine-covered back filled with venom, and has been responsible for several deaths, especially in southern Brazil
. This caterpillar has also been in numerous medical studies.
-like symptoms, spreading throughout the body, eventually causing massive blood leakage into the brain and, in several cases, death.
At first the cause could not be determined, although each victim stated they had “just handled a bunch of leafy branches to break the trail, or gather vegetation.” Exploring the area, the only creature commonly found within all the incidents was the Lonomia Caterpillar. With its hair growth covering its body, each clump of spines is able to easily puncture the skin and release toxins into the victim.
and a consumptive coagulopathy, which can lead to a hemorrhagic syndrome. It was soon discovered that at the base of each spine was a sack where the toxins were stored. As the stems and needles were stuck into the victim, venom would flow through the hollow needles and into the puncture wound.
It was also discovered that the toxin in this creatures skin held one of the strongest anti-clotting agents ever found in nature. This anti-clotting agent would attach with another protein to the body’s cells and cause them to leak as blood is unable to clot. This internal bleeding would fill the surrounding tissue with “bruised blood.” This internal bleeding spreads through the internal organs and eventually leads to compression and brain death. This accounts for the minimum of 500 deaths as a result of contact with Lonomia. Interestingly enough, the poison only takes effect in large amounts. In order to feel the extreme injuries caused by this creature, the victim would need at least 20 to 100 hundred stings.
The genus Lonomia includes 26 species found on the American Continent. However, only Lonomia obliqua and Lonomia achelous have caused severe accidents, leading to hemorrhagic syndrome. Since 1989 the number of human accidents caused by these caterpillars has been increasing in the southern region of Brazil. Most victims were male (63%), many were between 0 and 19 years old (45%), and lesions are especially common on the hands (38%). The reported death rate is 2.5%. An antiserum is produced by the Butantan Institute in São Paulo, Brazil. It effectively reverses the coagulation disorders induced by Lonomia obliqua venom, and patients treated with this antiserum recover rapidly.
, hematuria
, pulmonary and intracranial hemorrhages, and acute renal failure
.”
In another case, the internal bleeding spread throughout their lower body. While they did not die, the still had to receive medical attention quickly. One victim shares, “My name is Marianne: I am still interested in publications about the Lonomia obliqua caterpillars that are found in Brazil and some other South American countries. Three years ago I was a victim of this caterpillar poisoning, ending up with haemolysis and acute kidney injury while in Brazil, after visiting Iguassu Falls. I accidentally touched a tree with my left hand and this resulted in a painful rash and swelling thereafter. I took a photograph for identification in case I had contracted something unfamiliar. It took another 3 days before I requested medical attention as the initial symptoms had cleared after a few hours. Luck was on my side as I attended a medical conference and my local medical colleagues saved my life as they were able to contact the local public health office who then arranged for the antivenin to be delivered to the hospital I was admitted to obtain urgent medical advice.”
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. Its famous for its larvae form, rather than the adult moth, for several reasons. Recently announced in an episode of the Discovery Channel
Discovery Channel
Discovery Channel is an American satellite and cable specialty channel , founded by John Hendricks and distributed by Discovery Communications. It is a publicly traded company run by CEO David Zaslav...
, known as the “assassin caterpillar,” this caterpillar has a spine-covered back filled with venom, and has been responsible for several deaths, especially in southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. This caterpillar has also been in numerous medical studies.
Description
These caterpillars are about 4.5 -5.5 cm (about 2 in.) in length, with background colors ranging from green to brown. Well camouflaged, they have rows of tubercles crowned with whorls of easily detachable spines of different sizes.Discovery
It has been known for a while that many caterpillars cause irritation by discharging body hairs, or can be poisonous if ever ingested. However, until Lonomia was discovered it was not known that caterpillars can produce enough toxins to kill a human being. Lonomia obliqua is found in the south of Brazil in the States of Rio Grande do Sul, Santa Catarina and Paraná. The species appears to be spreading to the southeast of Brazil, and recent accidents with the species were reported in the states of São Paulo, Rio de Janeiro and Minas Gerais. Lonomia obliqua is also found in Uruguay, Paraguay and Argentina. It first became internationally known when an epidemic occurred in an agrarian community in Rio Grande do Sul, Brazil. Doctors were mystified when scores of patients came in with the same symptoms. The symptoms shown were haematoma and gangreneGangrene
Gangrene is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies . This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood...
-like symptoms, spreading throughout the body, eventually causing massive blood leakage into the brain and, in several cases, death.
At first the cause could not be determined, although each victim stated they had “just handled a bunch of leafy branches to break the trail, or gather vegetation.” Exploring the area, the only creature commonly found within all the incidents was the Lonomia Caterpillar. With its hair growth covering its body, each clump of spines is able to easily puncture the skin and release toxins into the victim.
Toxicity
As an article by Antonio Pinto stated, the Lonomia obliqua has a unique venom that causes disseminated intravascular coagulationDisseminated intravascular coagulation
Disseminated intravascular coagulation , also known as disseminated intravascular coagulopathy or consumptive coagulopathy, is a pathological activation of coagulation mechanisms that happens in response to a variety of diseases. DIC leads to the formation of small blood clots inside the blood...
and a consumptive coagulopathy, which can lead to a hemorrhagic syndrome. It was soon discovered that at the base of each spine was a sack where the toxins were stored. As the stems and needles were stuck into the victim, venom would flow through the hollow needles and into the puncture wound.
It was also discovered that the toxin in this creatures skin held one of the strongest anti-clotting agents ever found in nature. This anti-clotting agent would attach with another protein to the body’s cells and cause them to leak as blood is unable to clot. This internal bleeding would fill the surrounding tissue with “bruised blood.” This internal bleeding spreads through the internal organs and eventually leads to compression and brain death. This accounts for the minimum of 500 deaths as a result of contact with Lonomia. Interestingly enough, the poison only takes effect in large amounts. In order to feel the extreme injuries caused by this creature, the victim would need at least 20 to 100 hundred stings.
The genus Lonomia includes 26 species found on the American Continent. However, only Lonomia obliqua and Lonomia achelous have caused severe accidents, leading to hemorrhagic syndrome. Since 1989 the number of human accidents caused by these caterpillars has been increasing in the southern region of Brazil. Most victims were male (63%), many were between 0 and 19 years old (45%), and lesions are especially common on the hands (38%). The reported death rate is 2.5%. An antiserum is produced by the Butantan Institute in São Paulo, Brazil. It effectively reverses the coagulation disorders induced by Lonomia obliqua venom, and patients treated with this antiserum recover rapidly.
Effects of venom
Disseminated intravascular coagulation occurs as the toxin interacts with the victim’s body. One serious effect on envenomed victims is hemorrhage syndrome. “First described by Arocha-Pinango and Layrisse in Venezuela in 19671, the hemorrhagic diathesis caused in humans by touching the Lonomia species begins with inflammatory changes at the site of envenoming, followed by systemic symptoms such as headache, fever, vomiting and malaise. After 24 hours, a severe bleeding disorder ensues, leading to ecchymosisEcchymosis
An ecchymosis is the medical term for a subcutaneous purpura larger than 1 centimeter or a hematoma, commonly called a bruise. It can be located in the skin or in a mucous membrane.-Presentation:...
, hematuria
Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
, pulmonary and intracranial hemorrhages, and acute renal failure
Acute renal failure
Acute kidney injury , previously called acute renal failure , is a rapid loss of kidney function. Its causes are numerous and include low blood volume from any cause, exposure to substances harmful to the kidney, and obstruction of the urinary tract...
.”
Case studies
Although few cases are recorded, this is an example of a fatal encounter with this deadly caterpillar. “A 70 year-old, previously healthy woman developed a sudden coma. Four days before, she had started to present hematuria. Shortly after admission, her coma was rated as Glasgow 3. Physical examination revealed several skin hemorrhages, and gross hematuria was present. Based on information in a note left by the patient, two small hyperemic lesions were identified on the tip of her left toe. Along with the note was the green caterpillar which was hidden inside of her slipper. CT-scan imaging revealed multiple intracerebral hemorrhages. She died seven days after being envenomed.”In another case, the internal bleeding spread throughout their lower body. While they did not die, the still had to receive medical attention quickly. One victim shares, “My name is Marianne: I am still interested in publications about the Lonomia obliqua caterpillars that are found in Brazil and some other South American countries. Three years ago I was a victim of this caterpillar poisoning, ending up with haemolysis and acute kidney injury while in Brazil, after visiting Iguassu Falls. I accidentally touched a tree with my left hand and this resulted in a painful rash and swelling thereafter. I took a photograph for identification in case I had contracted something unfamiliar. It took another 3 days before I requested medical attention as the initial symptoms had cleared after a few hours. Luck was on my side as I attended a medical conference and my local medical colleagues saved my life as they were able to contact the local public health office who then arranged for the antivenin to be delivered to the hospital I was admitted to obtain urgent medical advice.”