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.

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.

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.

Gnathostomiasis acquired after consumption of raw freshwater fish in the Amazon region: a report of two cases in Brazil.

Gnathostomiasis is a parasitic zoonosis caused by the helminth Gnathostoma spp., acquired through the consumption of raw or undercooked contaminated aquatic animals.The disease is endemic in Southeast Asia and Central America. Two male patients, both middle-aged, presented with single itchy erythemato-edematous plaques on the anterior thorax and left flank. Both had consumed raw fish in the Amazon region. The clinical and epidemiological examinations suggested gnathostomiasis, and treatment with albendazole caused total regression of the lesions. Health teams should be familiar with the disease to provide correct diagnosis. The control strategy should be based on health education for the population.

Aseptic Folliculitis in Freshwater and Marine Fishermen.

Folliculitis is a common skin disease, usually benign, which causes inflammation and eventual infections of hair follicles. They may have an infectious etiology, mainly due to the bacteria Staphylococcus aureus; it also occurs due to localized irritation, such as in areas of skin friction and for long periods of immersion in water, as in athletes and workers who are continuously exposed to the aquatic environment. Herein, we report on two fishermen, from fluvial and maritime environments, who presented with chronic aseptic folliculitis associated with daily immersion of their lower extremities while exercising the profession and that regressed when there was a decrease in their contact with water.

Health-risk assessment of Portuguese man-of-war (Physalia physalis) envenomations on urban beaches in São Luís city, in the state of Maranhão, Brazil.

INTRODUCTION: The Portuguese man-of-war (Physalia physalis) is a cosmopolitan species, with a widespread distribution and responsible for a great number of injuries caused by cnidarians worldwide, including Brazil. Geoprocessing technology, however, has never been used to assess the spatial distribution of these animals on beaches. The aim of this study was to carry out a health risk assessment of Portuguese man-of-war (P. physalis) envenomations on the São Marcos and Calhau beaches in São Luís city, in the state of Maranhão, Brazil. METHODS: This is a descriptive and quantitative study concerning primary data on the occurrence of the Portuguese man-of-war (P. physalis) and human envenomations in the studied places, conducted over a two-year period in São Luís, Maranhão, northeastern Brazil. RESULTS: Envenomations mainly occurred on beaches presenting high density of P. physalis during the dry period. Vinegar has been incorporated as a first aid, according to recommendations set by the Brazilian Ministry of Health. CONCLUSIONS: In order to improve prevention and control actions of human envenomation, risk areas for this type of envenomation should be clearly indicated as alert areas. Inclusion of the geographical location of the envenomation in the Notification/Investigation SINAN Form was suggested for allowing the continuity of studies involving this public health issue.

Profile of skin diseases in a community of fishermen in the northern coast of the state of São Paulo: the expected and the unusual.

BACKGROUND: The fishing colony of the Picinguaba neighborhood is located at the northern end of the coast of the state of São Paulo. It has about 300 residents, of which approximately 100 are professional fishermen. OBJECTIVES: This study aimed to identify the main dermatoses of the community in comparison with other populations, and their frequency. METHODS: The dermatoses were identified and tabulated for two years, in a prospective study carried out on monthly trips to the fishermen's colony in Picinguaba. RESULTS: One hundred and eighteen patients were attended and followed up, which is equivalent to about 1/3 of the colony's inhabitants. Of these, 43 were children (under the age of 14) and 75 were adolescents and adults. The diseases observed were catalogued according to the age groups. Although most dermatoses in the community were similar with those observed in the general population, some specific cases could be seen, such as folliculitis on the legs of fishermen and an unexpected low frequency of actinic lesions in the colony, as well as dermatitis by aquatic animals. STUDY LIMITATIONS: The limitations were monthly attendance and the spontaneous demand of the patients. CONCLUSIONS: The finding of community-specific dermatoses and the low incidence of malignant and pre-malignant tumors associated with sun exposure needs further studies for better clarification.

Oral microbiota and their antibiotic susceptibility in free-living monkeys in Goiás State, Brazil: Repercussions for injuries in humans.

INTRODUCTION: Goiás State, which is in the midwest region of Brazil, has several urban forests. This fact, along with the expansion of urban areas within the limits of Forest Conservation Units, increases the contact between humans and wildlife, such as capuchin monkeys. The impulsive behavior of these animals and the scarcity of food cause them to vigorously search for food, leading to direct encounters with Park visitors, which can result in scratches and bites and making them potential disseminators of pathogenic microorganisms. METHODS: Ten specimens of bearded capuchin monkey (Sapajus libidinosus) were captured at the Onofre Quinan Environmental Park in Anápolis, Goiás, Brazil. Samples were collected from the monkeys, and the bacteria and fungi present in the samples were isolated and identified. Then, the identified microorganisms were subjected to antibiotic susceptibility testing. RESULTS: A total of 111 bacteria and 12 fungi were isolated, including two strict anaerobic bacteria of the genus Peptostreptococcus, 109 facultative anaerobic bacteria, and 12 yeasts. Among the facultative bacteria, enterobacteria and Staphylococcus were common. Resistance to tetracycline and ampicillin antibiotics was detected in the enterobacteria, and resistance to tetracycline, erythromycin, and clindamycin was detected in the Staphylococci. The other strains were sensitive to all tested antimicrobials. Cefoxitin showed 100% efficacy in all isolated bacteria. CONCLUSIONS: For bites from capuchin monkeys, we recommend performing complete hygiene and antibiotic therapy, according to medical recommendations. Given the 100% effectiveness of cefoxitin, it should be considered for this type of injury, especially in the study region.

Injuries caused by fish in a community of Pantanal fishermen: detection, treatment, and prevention of envenomations and trauma.

INTRODUCTION: Injuries caused by fish are common in the Pantanal, a flooded area in Midwestern Brazil. METHODS: A survey was conducted to identify venomous and trauma-inducing fish and the incidence of such injuries in a local fishing community. RESULTS: The injuries were caused by catfish, freshwater stingrays, and piranhas. All fishermen had suffered injuries, and nearly 30% had recent injuries. CONCLUSIONS: A leaflet and discussions decreased the injuries (only two were recorded in the next year). The campaign educated fishermen about prevention of and first aid for injuries. Similar campaigns will be performed in other communities of the Pantanal.

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.

Anaphylactic reaction/angioedema associated with jellyfish sting.

The most frequent jellyfish in Southern Brazil causes mainly local pain and skin plaques. A 3-year-old female bather presented an erythematous, irregular plaque on the left forearm after contact with a jellyfish and intense facial angioedema with facial flushing. The lungs had vesicular murmur, wheezes, and snorts, and pink and spumous secretion in the airways with intercostal retraction. She was administered subcutaneous adrenaline (0.1mg/kg) and hydrocortisone intravenous (10mg/kg) with total recovery in a few minutes. The manifestations of anaphylactic reactions are distinct from those of envenomations, and prompt and adequate care is fundamental in these situations.

Breakfast, lunch, and dinner sign: a hallmark of flea and bedbug bites.

Human, dog, and cat fleas, as well as bedbugs, feed by biting their victims, causing acute prurigo, which is aggravated in sensitized victims (papular urticaria). The lesions appear in the classic "breakfast, lunch, and dinner" pattern. There are two main explanations: the parasites "map" the skin area in search of the best places to bite, and their removal when victim scratches, and then reattach to the skin. Treatments aim to control pruritus, as well as hypersensitivity reactions when necessary. Prevention is based on environmental control measures. The "breakfast, lunch, and dinner" sign is a definitive marker for diagnosis and the parasite´s identification and control.

Acute prurigo simplex in humans caused by pigeon lice.

Pigeon lice are insects that feed on feathers of these birds; their life cycle includes egg, nymph and adult and they may cause dermatoses in humans. Four persons of the same family, living in an urban area, presented with widespread intensely pruritic erythematous papules. A great number of lice were seen in their house, which moved from a nest of pigeons located on the condenser of the air-conditioning to the dormitory of one of the patients. Even in urban environments, dermatitis caused by parasites of birds is a possibility in cases of acute prurigo simplex. Pigeon lice are possible etiological agents of this kind of skin eruption, although they are often neglected, even by dermatologists.

Comparative study on extracts from the tissue covering the stingers of freshwater (Potamotrygon falkneri) and marine (Dasyatis guttata) stingrays.

Stingrays are elasmobranchs found along the seacoast and in some rivers of Brazil. Pain is the most conspicuous symptom observed in patients wounded by the bilaterally retroserrate stingers located in the tail, which are covered by glandular and integument tissues. In addition, cutaneous necrosis is commonly observed in injuries caused by freshwater stingrays. The aim of this work was to characterize and compare certain properties of tissue extracts obtained from the glandular tissues covering the stinger apparatus of Potamotrygon falkneri and Dasyatis guttata stingrays. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), tissue extracts have similar bands above 80 kDa, but most differences were observed below this molecular mass. Lethal, dermonecrotic and myotoxic activities were detected only in P. falkneri tissue extract. Edematogenic activity was similar and dose dependent in both tissue extracts. Nociceptive activity was verified in both tissue extracts, but P. falkneri presented a two-fold higher activity than D. guttata tissue extract. No direct hemolysis, phospholipase A2 and coagulant activities were observed in both tissue extracts. Antigenic cross-reactivity was noticed by ELISA and Western blotting, using antisera raised in rabbits. Species-specific sera reacted with several components of both tissue extracts, noticeably above 22kDa. Both tissue extracts presented gelatinolytic, caseinolytic and fibrinogenolytic activities, which were not caused by the action of metalloproteinases. Hyaluronidase activity was detected only in P. falkneri tissue extract. Our experimental observations suggest that P. falkneri tissue extract is more toxic than D. guttata tissue extract. These results may explain why injuries caused by freshwater stingrays are more severe in human accidents.