Terrestrial venomous animals, the envenomings they cause, and treatment perspectives in the Middle East and North Africa

The Middle East and Northern Africa, collectively known as the MENA region, are inhabited by a plethora of venomous animals that cause up to 420,000 bites and stings each year. To understand the resultant health burden and the key variables affecting it, this review describes the epidemiology of snake, scorpion, and spider envenomings primarily based on heterogenous hospital data in the MENA region and the pathologies associated with their venoms. In addition, we discuss the venom composition and the key medically relevant toxins of these venomous animals, and, finally, the antivenoms that are currently in use to counteract them. Unlike Asia and sub-Saharan Africa, scorpion stings are significantly more common (approximately 350,000 cases/year) than snakebites (approximately 70,000 cases/year) and present the most significant contributor to the overall health burden of envenomings, with spider bites being negligible. However, this review also indicates that there is a substantial lack of high-quality envenoming data available for the MENA region, rendering many of these estimates speculative. Our understanding of the venoms and the toxins they contain is also incomplete, but already presents clear trends. For instance, the majority of snake venoms contain snake venom metalloproteinases, while sodium channel–binding toxins and potassium channel–binding toxins are the scorpion toxins that cause most health-related challenges. There also currently exist a plethora of antivenoms, yet only few are clinically validated, and their high cost and limited availability present a substantial health challenge. Yet, some of the insights presented in this review might help direct future research and policy efforts toward the appropriate prioritization of efforts and aid the development of future therapeutic solutions, such as next-generation antivenoms.

Animais Venenosos em Território Português: Abordagem Clínica de Picadas e Mordeduras

There are many native species of animals with the potential to cause severe disease in Portugal. Of the four clinically relevant snake species, the vipers (Vipera latastei and Vipera seoanei) are the most concerning. They can cause severe disease and require in-hospital management, monitoring and specific treatment, including the administration of anti-snake venom serum. The Malpolon monspessulanus and Macroprotodon brevis snakes cause mostly localized clinical manifestations, which do not require specific treatment. Only a minority of the spider species in Portugal possess chelicerae (mouthparts of the Chelicerata, shaped as either articulated fangs or pincers, which may contain venom or be connected to the venom glands and are used for predation or capture of food) long enough to perforate the human skin. Nevertheless, Latrodectus tredecimguttatus and Loxosceles rufescens spider bites may require specialized treatment in a hospital setting, as well as careful active symptom surveillance. Diversely, the treatment for Scolopendra cingulata and Scolopendra oraniensis centipedes’ bites is merely symptomatic. The only existing scorpion species in Portugal is the Buthus ibericus; its sting typically causes local symptoms with intense pain, and its treatment consists essentially of analgesia. The insects of the Hymenoptera order, such as bees and wasps, have the ability to inject venom into the skin. Most people present only with local or regional inflammatory response, and symptomatic treatment is usually effective. Even so, individuals with hypersensitivity to bee venom may develop anaphylaxis. Several marine species in the Portuguese coast are venomous to humans, including weeverfish (Trachinidae family), stingrays (Dasyatis pastinaca, Taeniura grabata, Myliobatis aquila), red scorpion fish (Scorpaena scrofa), cnidaria (Pelagia noctiluca, Chrysaora hysoscella, Physalia physalis) and bearded fireworm (Hermodice carunculata); treatment is symptomatic. Contact with the larvae or bristles (chitinous structures with locomotor or tactile functions) of Thaumetopoea pityocampa (pine processionary) can cause cutaneous, ocular and, rarely, respiratory reactions; its management is also symptomatic.

Uncommon differential diagnosis of a breast ulcer: a case study

Introduction: Spider bites are common worldwide. Frequently symptoms resolve without any adverse outcome, but in rare cases the bite can cause severe morbidity. The most typical presentation of Mediterranean recluse spider (Loxosceles Rufescens) bite is a dermatonecrotic lesion of the skin (skin loxoscelism). When the only manifestation of a spider bite is an ulcerated skin lesion, clinical suspicion and differential diagnosis strongly depend on its site. We present the case of an ulcerated wound of the breast, diagnosed as a Mediterranean recluse spider bite. Case presentation: A 79-year-old woman presented a 10cm-wide soft tissue ulceration of her left breast. At first, the diagnostic hypothesis of an ulcerated cancer was ruled out. Two family members revealed a recent history of Mediterranean recluse spider bite and the same clinical diagnosis was made for our patient. A wide excision was performed, with complete resolution of symptoms. Discussion: No specific diagnostic criteria for spider bites are available. Diagnosis is usually clinical. Skin loxoscelism could be easily mistaken for cellulitis, various types of skin infections, cutaneous anthrax, vasculitis, scorpion sting, pyoderma gangrenosum, erythema migrans of Lyme disease or prurigo nodularis. A thorough anamnestic interview is fundamental to raise the diagnostic hypothesis. When possible, a biopsy is recommended and it is extremely important when the ulcer can mimic a cancer, as is the case in breast tissue. Conclusion: We recommend a wide excision of the wound after failure of conservative treatment, in order to obtain local control and to perform histological examination on a more representative specimen.

SCIENTIFIC RATIONALITY, ADOPTION AND PERCEIVED EFFECTIVENESS OF ETHNOMEDICAL PRACTICES ON BITE REMEDIES IN IDUKKI, KERALA

The study was carried out among tribal farmers of Idukki district, Kerala. Forty gramapanchayats were selected for the study. A total of 90 tribal healers cum age-old farmers and 452 tribal farmers were the respondents of this study. The study recorded sixty eight EMPs on bite remedies. The prevalent categories of EMPs expertise were on poisonous bites (48.55%), snake bites (22.05%), scorpion bites (16.17%), spider bites (10.29%), and dog bites (2.94%). Of the sixty eight EMPs, seventeen were assessed for their scientific rationality and adoptions of which sixteen were studied for their perceived effectiveness among tribal farmers. Of the seventeen practices, fourteen were found to be rational, while the rest three were irrational. In this study, the scientific rationale behind fourteen rational EMPs was also explained. Sixteen practices were adopted by 51.32 to 83.18 percent of the respondents. Of the sixteen EMPs studied for effectiveness, all were perceived as effective by the tribal farmers, and this revealed that many EMPs on bite remedies were both rational and effective. This requires more clinical and pharmacological interference to validate and standardize EMPs, which will consecutively pave way for the development of low cost and effective alternative health care system.