A nationwide study of Vipera berus bites during one year-epidemiology and morbidity of 231 cases

Neutralization of Vipera and Macrovipera venoms by two experimental polyvalent antisera: a study of paraspecificity

We conducted an extensive study of neutralization of lethality of 11 species and one subspecies of snakes of the genus Vipera, and of five species of Macrovipera, by two experimental equine antisera. One antiserum was a trivalent preparation raised against the venoms of Vipera aspis aspis, Vipera berus berus and Vipera ammodytes ammodytes; the other was a pentavalent preparation that also included venoms of Vipera (now Montivipera) xanthina and Macrovipera lebetina obtusa. We measured specific neutralization of lethality against all venoms included in the immunization schemes, and paraspecific neutralization against the venoms of Vipera ammodytes montandoni, Vipera (Montivipera) bornmuelleri, Vipera latastei, Vipera (Mo.) latifii, Vipera (Mo.) lotievi, Vipera (Daboia) palaestinae, Vipera (Mo.) raddei and Vipera seoanei, as well as against Macrovipera (D.) deserti, Macrovipera lebetina cernovi, Macrovipera lebetina turanica and Macrovipera schweitzeri. We found an important degree of paraspecific protection within each genera (omitting recent reclassification) that was quite independent of both the lethal potency of the venoms and their geographic origin. This information may be of use to clinicians charged with the treatment of Vipera or Macrovipera envenomations with non-specific antivenoms.

A controlled clinical trial of a novel antivenom in patients envenomed by Bungarus multicinctus

In northern Vietnam, a majority of severely envenomed patients are bitten by Bungarus multicinctus. Hitherto, these victims have received supportive care only. The aims of this study were to assess the possible efficacy and side effects of a new antivenom. This trial (ClinicalTrials.gov Identifier: NCT00811239) was performed during 2004-2006 at an ICU in Hanoi. For ethical reasons, the study was not randomized. All patients who fulfilled the inclusion criteria during 2004-2005 were prospectively enrolled, carefully recorded, and treated with optimal supportive therapy (control group). The patients who entered the study 2006 were treated with antivenom in addition to supportive care (antivenom group). The inclusion criteria were: envenomation by B. multicinctus, presence of systemic envenomation, and (during 2006) provision of written informed consent. Predefined endpoints were number of patients requiring mechanical ventilation, duration of mechanical ventilation, length of ICU stay, duration of muscle paralysis, and number of patients with ventilator-associated pneumonia. Eighty-one patients were included, 54 during 2004-2005 and 27 during 2006. Baseline characteristics were similar in the groups. The antivenom-group patients had a shorter duration of muscle paralysis of the limbs (p < 0.001), of the diaphragm (p < 0.001), and of ptosis (p < 0.001). The duration of mechanical ventilation and length of ICU stay were shorter in the antivenom group (p < 0.001). The rate of ventilator-associated pneumonia was lower in the antivenom group (p < 0.02). However, the relative number of patients requiring mechanical ventilation was not reduced in the antivenom group. The rate of adverse reactions to the antivenom was 7.4%. A favorable efficacy and acceptable safety of this antivenom were demonstrated.

First clinical experiences about the neurotoxic envenomings inflicted by lowland populations of the Balkan adder, Vipera berus bosniensis

The first overall clinical description of envenomings by the lowland populations of the Balkan adder (Vipera berus bosniensis) is provided by this study. Fifty-four incidents have been collected retrospectively from the south-western Hungarian and the northern Croatian distribution area of the taxon. There were five (9%) asymptomatic, 24 (44%) mild, 12 (22%) moderate, 12 (22%) severe, and one fatal (2%) case according to the Poisoning Severity Score. The single death is a 60-year-old Hungarian case that was caused by V.b. bosniensis. Average hospitalisation was 2.75 days. The most common systemic symptoms were gastrointestinal disorders, ECG changes, persisting hypotension and neurological disorders. The initial phase of neurotoxic manifestations was always expressed in cranial nerve disturbances: ptosis, external ophthalmoplegia, diplopia, reduced focusing capability and blurred vision. Neuromuscular paralysis progressed to dyspnoea and lower limb paralysis in the most severe cases. Unusual symptoms were fluctuating arterial hypertension, drowsiness, and hypokalaemia. Laboratory results reveal leucocytosis, while deviation in the other laboratory values is not common. Envenomings by V.b. bosniensis significantly differ from those by the European adder (Vipera berus berus) in lower manifestation rate of extensive oedema, anaemia, CNS depression, and haematuria but the development of neuromuscular paralysis is high (20%). Their bites rather resulted in mild and moderate local symptoms in envenomed patients than those inflicted by the nominate form. This study presents the evidence of the frequent neurotoxic manifestations in Balkan adder-bitten patients for the first time, which strongly suggests that the venom of the lowland populations of V.b. bosniensis has neurotoxic activity.

Adder bite: an uncommon cause of compartment syndrome in northern hemisphere

Snakebite envenomation is an uncommon condition in the northern hemisphere, but requires high vigilance with regard to both the systemic effects of the venom and the locoregional impact on the soft tissues. Bites from the adder, Vipera Berus, may have serious clinical consequences due to systemic effects. A case of a 44-year-old man is reported. The patient was bitten in the right hand. He developed fasciotomy-requiring compartment syndrome of the upper limb. Recognition of this most seldom complication of an adder bite is vital to save the limb. We recommend that the classical signs and symptoms of compartment syndrome serve as indication for surgical decompression.

Envenoming following bites by the Balkan adder Vipera berus bosniensis - first documented case series from Bulgaria

We report the first detailed accounts of bites by the Balkan adder, Vipera berus bosniensis from Bulgaria. Documentation of bites by this subspecies is very rare in the literature and most available accounts are from the northern limit of its distribution. V. berus bosniensis is considered to possess neurotoxic venom but little evidence has hitherto been available to support this supposition. In this case series symptoms typical of adder bites developed including oedema, nausea, dizziness, lymphangitis, vomiting, and diarrhoea together with aberrant symptoms such as diplopia and ptosis that confirm the presence of neurotoxic venom in Balkan adders. In addition, unusual and atypical symptoms of adder bites such as painless bites and muscle cramps appeared. The inadequate treatment in hospital and the remote habitats in which this species is encountered are potential sources of complication.

Clinical and biochemical changes in 53 Swedish dogs bitten by the European adder--Vipera berus

BACKGROUND

Every year many dogs in Sweden are bitten by Vipera berus, the only venomous viper in Sweden. This prospective study investigated clinical signs, some biochemical parameters, treatment, and progress of disease after snakebite in 53 dogs. Effects of treatment with and without glucocorticoids were evaluated.

METHODS

All fifty-three dogs bitten by Vipera berus were examined the same day the dog was bitten and the next day. Two more examinations during 23 days post snake bite were included. Creatinine, creatine kinase (CK), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), alkaline phosphatase (ALP) and bile acid results were followed through 3 to 4 samplings from 34 of the dogs.

RESULTS

All dogs had variable severity of local swelling in the bite area and 73 per cent had affected mental status. Initial cardiac auscultation examination was normal in all dogs, but six dogs had cardiac abnormalities at their second examination, including cardiac arrhythmias and cardiac murmurs. All dogs received fluid therapy, 36 dogs were given analgesics, 22 dogs were treated with glucocorticoids, and ten dogs were treated with antibiotics. Evidence of transient muscle damage (increased CK) was seen one day after the snake bite in 15 (54%) of 28 sampled dogs. Moderate changes in hepatic test results occurred in 1 dog and several dogs (22 of 34) had transient, minor increases in one or more hepatic test result. No dog died during the observation period as a consequence of the snake bite.

CONCLUSIONS

Snake bite caused local swelling in all dogs and mental depression of short duration in most dogs. Some dogs had transient clinical signs that could be indicative of cardiac injury and some other had transient biochemical signs of liver injury. Treatment with glucocorticoids did not have any clear positive or negative effect on clinical signs and mortality.

Life-threatening systemic toxicity and airway compromise from a common European adder bite to the tongue

A 24-year-old man was bit on the tongue by a European common adder. Within 15 min following envenomation, he experienced tongue swelling, hypotension and impaired consciousness. Antihistamine, corticosteroid and crystalloids were administered. Within 105 min of envenomation, increasing oral, pharyngeal and facial oedema compromised the airway, leading to respiratory failure, concomitant with circulatory failure related to hypoxaemia and systemic toxic effects. Acute tracheotomy secured the airway, and two doses of antivenom successfully treated the systemic, toxic effects. The reaction was severe due to rapid and suspected high-dose uptake of venom, underlining the need for early advanced symptomatic treatment with airway control and early and eventually repeated dosing of antivenom.

[Adder bite. A rare dermatologic emergency]

Bites by poisonous snakes are rare dermatologic emergencies. A 43-year-old woman was bitten on her right forefinger by an adder during a hiking vacation in Austria. Her right arm and chest wall became swollen and then hemorrhagic, but she responded well to analgesics and immobilization. Administration of a specific antiserum was not necessary because of the lack of a systemic reaction.

The global burden of snakebite: a literature analysis and modelling based on regional estimates of envenoming and deaths

BACKGROUND

Envenoming resulting from snakebites is an important public health problem in many tropical and subtropical countries. Few attempts have been made to quantify the burden, and recent estimates all suffer from the lack of an objective and reproducible methodology. In an attempt to provide an accurate, up-to-date estimate of the scale of the global problem, we developed a new method to estimate the disease burden due to snakebites.

METHODS AND FINDINGS

The global estimates were based on regional estimates that were, in turn, derived from data available for countries within a defined region. Three main strategies were used to obtain primary data: electronic searching for publications on snakebite, extraction of relevant country-specific mortality data from databases maintained by United Nations organizations, and identification of grey literature by discussion with key informants. Countries were grouped into 21 distinct geographic regions that are as epidemiologically homogenous as possible, in line with the Global Burden of Disease 2005 study (Global Burden Project of the World Bank). Incidence rates for envenoming were extracted from publications and used to estimate the number of envenomings for individual countries; if no data were available for a particular country, the lowest incidence rate within a neighbouring country was used. Where death registration data were reliable, reported deaths from snakebite were used; in other countries, deaths were estimated on the basis of observed mortality rates and the at-risk population. We estimate that, globally, at least 421,000 envenomings and 20,000 deaths occur each year due to snakebite. These figures may be as high as 1,841,000 envenomings and 94,000 deaths. Based on the fact that envenoming occurs in about one in every four snakebites, between 1.2 million and 5.5 million snakebites could occur annually.

CONCLUSIONS

Snakebites cause considerable morbidity and mortality worldwide. The highest burden exists in South Asia, Southeast Asia, and sub-Saharan Africa.

Effects of bites by the European adder (Vipera berus) in seven Swedish horses

The effects on seven horses of bites by the European adder (Vipera berus) are described and compared with previously available information. The clinical signs varied from local swelling and mild systemic signs to severe systemic signs, including systemic inflammatory response, severe tissue necrosis, ventricular tachycardia and dysphagia. Two of the horses were treated with 'Zagreb' antiserum, and three that were not treated with antiserum were euthanased owing to complications related to the bites.