Envenomations caused by fish in Brazil: an evolutionary, morphological, and clinical vision of a neglected problem.

Venomous fish are commonly found in Brazilian waters. The most important marine venomous fish species are stingrays (Dasyatidae, Gimnuridae, Myliobatidae, and Rhinopteridae families), catfish (Ariidae family), scorpionfish and lionfish (both Scorpaenidae family), and toadfish (Batrachoididae family). Meanwhile, Potamotrygonidae stingrays and Pimelodidae catfish are the most important venomous freshwater fish. The mechanisms of envenomation vary and involve various venomous apparatuses and glands. Despite not being highly developed, these venomous apparatuses in fish appear rudimentary, using structures such as fins and rays to inoculate toxins and rarely presenting with specialized structures. Toxins are produced by glandular tissue made up of proteinaceous cells, lacking true glands, and are positioned along the inoculation structures. However, systemic manifestations are rare. No antivenom serum has been developed for any species of American venomous fish. Brazilian venomous fish and their venoms have only recently attracted attention, leading to new studies not only addressing clinical issues in humans, but also exploring the discovery of new active substances with immense pharmacological potential.

Envenomations caused by fish in Brazil: an evolutionary, morphological, and clinical vision of a neglected problem

ABSTRACT Venomous fish are commonly found in Brazilian waters. The most important marine venomous fish species are stingrays (Dasyatidae, Gimnuridae, Myliobatidae, and Rhinopteridae families), catfish (Ariidae family), scorpionfish and lionfish (both Scorpaenidae family), and toadfish (Batrachoididae family). Meanwhile, Potamotrygonidae stingrays and Pimelodidae catfish are the most important venomous freshwater fish. The mechanisms of envenomation vary and involve various venomous apparatuses and glands. Despite not being highly developed, these venomous apparatuses in fish appear rudimentary, using structures such as fins and rays to inoculate toxins and rarely presenting with specialized structures. Toxins are produced by glandular tissue made up of proteinaceous cells, lacking true glands, and are positioned along the inoculation structures. However, systemic manifestations are rare. No antivenom serum has been developed for any species of American venomous fish. Brazilian venomous fish and their venoms have only recently attracted attention, leading to new studies not only addressing clinical issues in humans, but also exploring the discovery of new active substances with immense pharmacological potential.

Lesions caused by human and domestic and wild animal bites.

Animal bites are a common problem in the emergency room. There are many reports of isolated cases (mainly of domestic mammals); however, texts with more comprehensive and general guidance on these kinds of bite injuries are necessary, including those caused by wild mammals, reptiles, and even fish. This review aims to update knowledge on this problem, which includes human and domestic and wild animal bites. Health teams in emergency care centers should be aware of the initial and late measures required to control this problem.

Mapping of the venomous stingrays of the Potamotrygon genus in the Tietê River, São Paulo Sstate, Brazil.

BACKGROUND: Freshwater stingrays are fish that have adapted to the rivers and lakes in South America. The expansion of the Potamotrygonidae family in the Paraná River began after the damming of the Sete Quedas Falls, reaching the mouth of the Paranapanema and Tietê rivers approximately 20 years ago via the locks of the hydroelectric power plants. They are not aggressive animals; however, they have one to four stingers on their tails covered by a venom-producing epithelium and can cause severe envenomation in fishermen and bathers if stepped on or manipulated. METHODS: We conducted a descriptive, retrospective, and prospective study by monitoring the fishing of the Potamotrygon genus in the lower Tietê River, mapping the location of the rays as a fishery product of professional fishermen and/or recording images of the fish caught. RESULTS: Sixteen stingrays of the Potamotrygon genus were mapped by monitoring fishermen's fish products in the extensive area between the municipalities of Pereira Barreto and Buritama, São Paulo state. CONCLUSIONS: The lower Tietê River is fully colonized by freshwater stingrays and this expansion likely continues upstream, reaching various sub-basins of the river. The advancement of these venomous fish in areas where they did not exist previously requires education programs and interaction with the community to avoid serious injuries in bathers and fishermen and the unreasonable extermination of the animals.

Centipede envenomation (Chilopoda): Case report.

Centipedes are venomous arthropods that have an elongated body, divided into many segments, presenting a pair of legs in each segment, adapted pairs of paws that simulate fangs and inject venom causing intense pain, with local erythema and edema, and rarely, blisters and skin necrosis. We present the case of a young woman pricked on her upper lip with intense swelling and local pain and discuss the real danger of envenomation and the therapeutic measures that should be taken.

Mapping of the venomous stingrays of the Potamotrygon genus in the Tietê River, São Paulo Sstate, Brazil

ABSTRACT Background: Freshwater stingrays are fish that have adapted to the rivers and lakes in South America. The expansion of the Potamotrygonidae family in the Paraná River began after the damming of the Sete Quedas Falls, reaching the mouth of the Paranapanema and Tietê rivers approximately 20 years ago via the locks of the hydroelectric power plants. They are not aggressive animals; however, they have one to four stingers on their tails covered by a venom-producing epithelium and can cause severe envenomation in fishermen and bathers if stepped on or manipulated. Methods: We conducted a descriptive, retrospective, and prospective study by monitoring the fishing of the Potamotrygon genus in the lower Tietê River, mapping the location of the rays as a fishery product of professional fishermen and/or recording images of the fish caught. Results: Sixteen stingrays of the Potamotrygon genus were mapped by monitoring fishermen's fish products in the extensive area between the municipalities of Pereira Barreto and Buritama, São Paulo state. Conclusions: The lower Tietê River is fully colonized by freshwater stingrays and this expansion likely continues upstream, reaching various sub-basins of the river. The advancement of these venomous fish in areas where they did not exist previously requires education programs and interaction with the community to avoid serious injuries in bathers and fishermen and the unreasonable extermination of the animals.

Lesions caused by human and domestic and wild animal bites

ABSTRACT Animal bites are a common problem in the emergency room. There are many reports of isolated cases (mainly of domestic mammals); however, texts with more comprehensive and general guidance on these kinds of bite injuries are necessary, including those caused by wild mammals, reptiles, and even fish. This review aims to update knowledge on this problem, which includes human and domestic and wild animal bites. Health teams in emergency care centers should be aware of the initial and late measures required to control this problem.

Centipede envenomation (Chilopoda): Case report

ABSTRACT Centipedes are venomous arthropods that have an elongated body, divided into many segments, presenting a pair of legs in each segment, adapted pairs of paws that simulate fangs and inject venom causing intense pain, with local erythema and edema, and rarely, blisters and skin necrosis. We present the case of a young woman pricked on her upper lip with intense swelling and local pain and discuss the real danger of envenomation and the therapeutic measures that should be taken.

Reparo de lesão vascular não letal causada por tamanduá-bandeira (Myrmecophaga tridactyla) no Brasil / Repair of non-lethal vascular injury caused by giant anteater (Myrmecophaga tridactyla) in Brazil

Resumo O tamanduá-bandeira é um mamífero encontrado na América Central e na América do Sul. Esse animal possui garras que podem chegar a 6,5 cm de comprimento, utilizadas para escavar formigueiros e obter alimento, além de servir para sua defesa. Relatamos o caso de paciente masculino de 52 anos, com histórico de epilepsia, que foi levado desacordado ao pronto-socorro, devido a lesões no seu braço direito causadas por um tamanduá. Frente à suspeita de trauma vascular, o paciente foi submetido a exploração cirúrgica, que evidenciou uma lesão combinada de vasos braquiais, submetida a reparo. Apresentou boa evolução do quadro, recebendo alta hospitalar no segundo dia de pós-operatório e, no seguimento ambulatorial, evoluiu sem sequelas neurológicas ou vasculares.

Abstract The giant anteater is a mammal found in Central and South America. These animals have claws that can reach 6.5 centimeters in length, which they use to dig anthills to obtain food and for defense. We report the case of a 52-year-old male patient with a history of epilepsy who was taken unconscious to the emergency room due to injuries to his right arm caused by an anteater. He underwent surgical exploration to investigate suspected vascular trauma, revealing a combined (arterial and venous) injury of the brachial vessels, which were repaired. He recovered well and was discharged on the second postoperative day. During outpatient follow-up he continued to improve, with no neurological or vascular sequelae.

Injuries in humans caused by mantis shrimp or siriboia (Crustacea: Stomatopoda).

INTRODUCTION: Mantis shrimps or siriboias are crustaceans belonging to the order Stomatopoda. They are known for their strong claws, which they use for defense and capturing their prey. They are classified into two groups: the spearers, which pierce the prey with sharp projections, and the smashers, which strike their prey with high-powered punches. These animals are highly feared by fishermen, and there are frequent anecdotal reports of human injuries caused by these crustaceans. METHODS: A questionnaire about injuries in humans caused by these stomatopods was administered to 23 fishermen of Colony Z10 in Ubatuba, São Paulo state, Brazil, and a survey of the literature on injuries in humans caused by these animals was carried out. RESULTS: The fishermen consider the mantis shrimp dangerous and avoid direct contact with them on account of the associated risk. We describe five reports of human injuries caused by these animals: four by the claws and one by the tail spikes. CONCLUSIONS: We describe the first aid treatment, prevention, and recommendations for such cases and propose the distribution of educational leaflets among the fishermen colonies.