Snake venom poisoning in the Plovdiv region from 2004 to 2012

Envenomation by poisons of biological origin is very common globally in the tropical and subtropical areas mainly, where the biological diversity of the species clearly leads to evolution of highly toxic species. The weather warming trend in Bulgaria, whether cyclic or permanent, allows for a change in the biological response of reptiles and insects inhabiting the temperate zone by a possible migration of biological species from the subtropical zone towards the temperate zone because of the new environmental conditions. There are very few studies on snake bite envenoming in Bulgaria. The AIM of the study was to find the incidence of the acute accidental intoxication (AAI) caused by snake venom in adult individuals in a large region of Bulgaria between 2004 and 2012 and characterises it by number, type, main clinical features, course and socio-demographic parameters of the victims so that preventive measures can be taken, wherever necessary.

We studied retrospectively all 68 cases of AAI caused by snake venom in adult individuals (> 18 years old) hospitalized in the Clinic of Toxicology in St. George University Hospital, Plovdiv over the period from 2004 to 2012 by 23 quantitative and qualitative parameters.

We found that the average annual incidence of snake venom AAI in adult population in the region of Plovdiv was relatively low for the specified period (9.5 per 100000 residents); the snake venom AAI increases or decreases every other year, with no clearly delineated trend for now. The prevalence of envenomation by poisons of biological origin increased from 2.3% in 1990-1998 to 9.5-10.33% between 2007 and 2012. The main sociodemographic characteristics of snake bite victims are similar to those in other Balkan and Central European countries. The clinical response to poisons of biological origin is generally identical with the response to the viper (Vipera ammodytes)--mild to medium intensity with predominantly local toxic syndrome.

The algorithm of Clinical Pathway 293 (CP) is effective and conducive to the reduction of duration of the morbid condition. There are, however, still aspects of it that can be optimised.