*1.1. The Origins of Negligence*

There are twenty (tropical) diseases that are officially classified as 'neglected tropical diseases' by the World Health Organization (WHO) [2]. Neglected tropical diseases persist under conditions of poverty and are concentrated almost exclusively in impoverished populations in the developing world. They are: Buruli ulcer, Chagas disease, Dengue and Chikungunya (only WHO, not CDC), Dracunculiasis, Echinococcosis, Yaws, Fascioliasis, African trypanosomiasis, Leishmaniasis, Leprosy, Lymphatic filariasis, Onchocerciasis, Rabies, Schistosomiasis, Soiltransmitted helminthiasis, Cysticercosis, Trachoma, Scabies and other ectoparasites, Snakebite envenoming, Mycetoma and deep mycoses. These diseases are common in 149 countries, affecting more than 1.4 billion people (including more than 500 million children) and costing developing economies billions of dollars every year.

The importance of neglected tropical diseases has been underestimated since many are asymptomatic and have long incubation periods. The connection between a death and a neglected tropical disease that has been latent for a long period of time is not often realized. Additionally, neglected tropical diseases are often associated with some kind of social stigma, making their treatment more complex.

From the toxinology perspective, one can also consider that there are 'neglected' venomous and poisonous animals by employing very similar criteria to justify such negligence: Human accidents occur with individuals who are often amongst the poorest populations, living in remote, rural areas, urban slums or conflict zones; the accident causes no rapid death of the victim and/or such animals are stigmatized (cause bad luck, carry evil spells or are cursed).

Depending on the nature and origin of the venom or toxin, one can clearly perceive that there are 'preferred' subjects and matters in the field of toxinology (Table 1). Probably due to historical and/or epidemiological factors, some animals and venoms—normally the ones that elicit acute, severe lesions due to some pronounced biological activity—were selected (or elected) as 'more relevant' to the field and have been thoroughly studied throughout the years. Endemic animals, such as spiders and scorpions that have adapted to urban environments, have also 'deserved' more attention than other species. All the consulted databases indicated that there is more literature on snakes, spiders and scorpions (the triad) than the others. Interestingly, Scopus and Web of Science present the same publications ratio for triad:neglected (7.8), whereas Google and PubMed display lower ratios (5.5 and 1.8 respectively), probably due to the differences in indexed publications queried.

**Table 1.** Total results retrieved according to the searched terms in different academic databases.


Search performed in 11 September 2021. <sup>1</sup> Limited to skin, in order to exclude ecological studies; <sup>2</sup> Limited to toxin, in order to exclude developmental/reproductive models; <sup>3</sup> Limited to toxins and excluding dinoflagellates.

> The aim of this review is, therefore, to shed a light upon such amazing animals and their venoms and secretions, presenting a non-anthropocentric view of their venom composition and the (few, but consistent) biomedical 'cases' derived from the study of such species, and review the literature and the biotechnological developments derived from venoms and secretions from toxic animals that have not received proper attention from the scientific community over the past years and cast a light on their unique features and interesting molecules. Afterall, just like the neglected tropical diseases, it was never about the 'importance' of these animals, only their 'relevance', i.e., their economic impact, geopolitical localization, affected population, endangerment status and profit potential, in addition to formerly listed reasons.
