Spider bites in France: Epidaemiology of cases occurring in 10 years in metropolitan France.

Spiders are often wrongly designated as responsible for cutaneous eruptions. We aim to describe spider bites and the spider species implicated in metropolitan France. A retrospective observational study was conducted for all reported cases of spider bites from 2007 to 2018 extracted from the French Poison Control Centers (PCCs) information system, after exclusion of non-native spiders. We described identification of the spider, level of certainty of the bite, symptoms and severity of cases. 1194 cases of spider bites met the inclusion criteria. The average age of the patients was 36.9 ± 19.8 years. Identification of the species or at least that a spider was implicated was only possible in 346 cases (29.0%). Loxosceles were involved in 53 cases (4.4%), Latrodectus in 46 cases (3.9%) and Cheiracanthium in 35 cases (2.9%). In one third of cases, the involved spider was not known to be present where the bite occurred. Where most of the patients (n = 1111, 93%) reported at least one cutaneous symptom, most of the symptoms were neurological. The bite was considered proven in only 242 cases (20%). Despite the efforts of arachnologists to educate the public, the fear of spiders is still alive in France, where spider bite is rare with low severity and often unproven.

[Loxoscelism. Experience in 200 patients]. / Caracterización clínica y epidemiológica de 200 pacientes con loxoscelismo cutáneo y cutáneo visceral.

BACKGROUND: Loxoscelism is an important public health problem in Chile and South America, due to the higher rate of cutaneous-visceral involvement. The diagnosis of loxoscelism is mostly clinical without established diagnostic criteria. There is little evidence to support any treatment used in this condition. AIM: To characterize the clinical features and epidemiology of loxoscelism among patients consulting at the Emergency and Dermatology Services of a clinical hospital between 2013 and 2017. MATERIAL AND METHODS: Review of medical records of patients registered in the electronic clinical record system with a confirmed diagnosis of loxoscelism. Epidemiological, clinical, laboratory tests and treatment variables were analyzed. RESULTS: We reviewed data from 200 patients. Ninety-four percent presented cutaneous loxoscelism and 5.5% cutaneous-visceral loxoscelism. Systemic symptoms were present in 73% of patients with cutaneous-visceral loxoscelism. Patients who developed systemic symptoms had an 18 times higher risk of developing cutaneous-visceral loxoscelism. Laboratory abnormalities were more common in patients with cutaneous-visceral loxoscelism. Not all patients with hematuria had cutaneous-visceral loxoscelism. Most patients required analgesia. Anti-loxosceles serum was not used in any patient. CONCLUSIONS: Many questions remain to be answered regarding the diagnosis and treatment of the disease. Studies are required to validate diagnostic criteria for loxoscelism, predictors for visceral involvement and response to treatment.

Clinical aspects, diagnosis and management of Loxosceles spider envenomation: literature and case review.

The genus Loxosceles comprises 140 species widely distributed around the world. These spiders are nocturnal, sedentary and remarkably nonaggressive, although they cause accidents in humans with wide degrees of severity, generating signs and symptoms that define the clinical condition known as loxoscelism. Its local signs and symptoms were first reported in 1872, and over the years, a large medical literature has been accumulated; unfortunately, it is not always trustworthy. Assessing the reliability of such information, we reviewed 120 case reports of loxoscelism published in 84 articles over the past 20 years. This search allowed us to gather information on the clinical aspects, diagnosis and treatment of loxoscelism, showing that the severity of these accidents has multiple degrees and that it is influenced by many factors. Thus, coupled with epidemiological and species occurrence information, this study can be a useful tool for the clinical practice of loxoscelism. It may support and provide a multidisciplinary view that should be taken into consideration when establishing the therapeutic approach in cases of Loxosceles envenomation.

National Estimates of Noncanine Bite and Sting Injuries Treated in US Hospital Emergency Departments, 2011-2015.

OBJECTIVES: Injuries resulting from contact with animals are a significant public health concern. This study quantifies and updates nonfatal bite and sting injuries by noncanine sources using the most recent data available (2011-2015) from the National Electronic Injury Surveillance System-All Injury Program with the purpose of using these updates to better understand public health consequences and prevention techniques. Increased rates of bites and stings can be expected in this study's time frame, possibly caused by the increasing human population expanding into animal territories, as well as changes in animal geographic distribution and pet ownership. METHODS: The National Electronic Injury Surveillance System-All Injury Program is an ongoing nationally representative surveillance system used to monitor all types and causes of injuries treated in US hospital emergency departments (EDs). Cases were coded by trained hospital coders using information from medical records on animal sources of bite and sting injuries being treated. Data from 2011-2015 were weighted to produce national annualized estimates, percentages, and rates based on the US population. RESULTS: An estimated 1.17 million people visited EDs for noncanine bite and sting injuries annually. This translates to a rate of 371.3/100,000 people. Insects accounted for 71.0% of noncanine bite and sting injuries, followed by arachnids (19.2%) and mammals (7.8%). The estimated annual total lifetime medical and work cost of unintentional noncanine injuries was $5,755,581,000. CONCLUSIONS: Various sources of bite and sting injuries had an outsized effect on injury rates and identify potential areas of focus for education and prevention programs to reduce the burden of these injuries on health and healthcare costs. The study describes the diversity of animal exposures based on a national sample of EDs. Noncanine bite and sting injuries significantly affect public health and healthcare resources. Priorities can be focused on animal sources with the most impact on bite and sting injury rates, healthcare costs, and disease burden.

Matching global and regional distribution models of the recluse spider Loxosceles rufescens: to what extent do these reflect niche conservatism?

The Mediterranean recluse spider, Loxosceles rufescens (Dufour, 1820) (Araneae: Sicariidae) is a cosmopolitan spider that has been introduced in many parts of the world. Its bite can be dangerous to humans. However, the potential distribution of this alien species, which is able to spread fairly quickly with human aid, is completely unknown. Using a combination of global and regional niche models, it is possible to analyse the spread of this species in relation to environmental conditions. This analysis found that the successful spreading of this species varies according to the region invaded. The majority of populations in Asia are stable and show niche conservatism, whereas in North America this spider is expected to be less successful in occupying niches that differ from those in its native region and that do not support its synanthropic way of living.

Treatment of pediatric black widow spider envenomation: A national poison center's experience.

BACKGROUND: Black widow species (Latrodectus species) envenomation can produce a syndrome characterized by painful muscle rigidity and autonomic disturbances. Symptoms tend to be more severe in young children and adults. We describe black widow spider exposures and treatment in the pediatric age group, and investigate reasons for not using antivenom in severe cases. METHODS: All black widow exposures reported to the Rocky Mountain Poison Center between January 1, 2012, and December 31, 2015, were reviewed. Demographic data were recorded. Patients were divided into 2 groups. Group 1: contact through families from their place of residence, public schools and/or cases where patients were not referred to healthcare facilities. Group 2: patient contact through healthcare facilities. RESULTS: 93 patients were included. Forty (43%) calls were in Group 1 and 53 (57%) in Group 2. Symptoms were evident in all victims; 43 (46.2%) were grade 1, 16 (17.2%) grade 2 and 34 (36.5%) grade 3, but only 14 patients (41.1%) of this group received antivenom. Antivenom use was associated with improvement of symptoms within minutes, and all treated patients were discharged within hours, without an analgesic requirement or any complications. Reasons for not receiving antivenom included: skin test positive (2/20), strong history of asthma or allergies (2/20), physician preference (2/20), non-availability of the antivenom at the health care facility (14/20). CONCLUSION: In our study, most symptomatic black widow envenomations were minor. Relatively few patients received antivenom, but antivenom use was associated with shorter symptom duration among moderate and major outcome groups.

Niche modelling of the Chilean recluse spider Loxosceles laeta and araneophagic spitting spider Scytodes globula and risk for loxoscelism in Chile.

In Chile, all necrotic arachnidism is attributed to the Chilean recluse spider Loxosceles laeta (Nicolet) (Araneae: Sicariidae). It is predated by the spitting spider Scytodes globula (Nicolet) (Araneae: Scytodidae). The biology of each of these species is not well known and it is important to clarify their distributions. The aims of this study are to elucidate the variables involved in the niches of both species based on environmental and human footprint variables, and to construct geographic maps that will be useful in estimating potential distributions and in defining a map of estimated risk for loxoscelism in Chile. Loxosceles laeta was found to be associated with high temperatures and low rates of precipitation, whereas although S. globula was also associated with high temperatures, its distribution was associated with a higher level of precipitation. The main variable associated with the distribution of L. laeta was the human footprint (48.6%), which suggests that this is a highly invasive species. Similarly to other species, the distribution of L. laeta reaches its southern limit at the Los Lagos region in Chile, which coincides with high levels of precipitation and low temperatures. The potential distribution of L. laeta in Chile corresponds to the distribution of cases of loxoscelism.

[Neurotoxic manifestations of black widow spider envenomation in paediatric patients]. / Manifestaciones de neurotoxicidad en el envenenamiento por mordedura de araña «viuda negra¼ en edades pediátricas.

INTRODUCTION: Envenomation by black widow spiders manifests clinically with signs of neurotoxicity in paediatric patients. OBJECTIVE: Identify typical neurological signs and symptoms in paediatric patients of different ages, and describe treatment and outcomes in a paediatric hospital in northwest Mexico. MATERIAL AND METHODS: We reviewed 70 clinical records of patients hospitalised due to black widow spider bite between 1978 and 2014. We divided the total into 2 groups: Group 1, infants and preschool children; and Group 2, school-age children and adolescents. The demographic variables were age, sex, birthplace, place where envenomation occurred, body part(s) affected, degree of envenomation according to signs and symptoms, treatment, clinical outcome, and statistical differences. RESULTS: Boys accounted for 61.4% of all cases, and infants younger than one year old made up 14.2%. Most patients (70%) were bitten by the spider at home; the anatomical areas most frequently affected were the legs, neck, thorax, and abdomen. The neurological signs and symptoms displayed by Group 1 were irritability, constant crying, sialorrhoea, nausea, tachycardia, arrhythmias, fatigue when walking, agitation, muscle spasms paraesthesia, tetany, seizures, and nystagmus. Signs in Group 2 included localized pain, headache, sialorrhoea, paraesthesia, profuse sweating, anxiety, muscle weakness, muscle spasms, and fine tremor. The predominant autonomic sign in Group 1 was sialorrhoea (P<.0001) and in Group 2, paraesthesia (P<.0001). Patients who received Fab antivenom treatment displayed better outcomes and shorter hospital stays than those who did not. No deaths were reported. CONCLUSIONS: The neurological signs and symptoms caused by black widow spider bite are predominantly autonomic, and identifying them permits early diagnosis and more effective treatment.

Envenomation by Trachelas tranquillus (Araneae: Corrinidae) in Connecticut.

We report a case of envenomation by Trachelas tranquillus (Hentz) in Connecticut in late September 2013. The bitten subject, a 50 yr-old-female Caucasian, reported a painful wasp-like sting and brushed the spider from her leg. An erythematous macule formed at the site of the bite. The macule was gone by the next day and there was no associated necrosis. The spider was collected and brought to our laboratory for identification. This is the second confirmed case of envenomation by T. tranquillus and the only case reported from Connecticut.

Comparative medical importance of spider bites in Spain over 1997-2020: a retrospective study based on hospital cases coded using ICD.

Envenomation by terrestrial toxic animals is considered a serious risk to human health worldwide. Snakes, hymenopterans, spiders, and scorpions have mainly attracted the attention of medical literature. However, the relative importance of spiders has been studied only in a few countries. Here, we present the first retrospective study on the incidence of spider bites requiring hospital care in Spain, compared to bites or stings from snakes, hymenopterans, and scorpions. Using ICD9MC and ICD10 databases from the World Health Organization's International Classification of Diseases for the period 1997-2020, we quantified the cases of envenomation by spiders, compared to those by other terrestrial toxic animals, the demographic data of envenomation cases, the relative severity of spider bites, and the geographic distribution of envenomation cases. Overall, the incidence of acute intoxication by terrestrial toxic animals in Spain was ca. 1.23 cases per million inhabitants. In decreasing order of importance, cases were due to snakes, hymenopterans, spiders, scorpions, and myriapods. Fatal cases were extremely rare, caused mainly by hymenopterans. No fatalities were caused by spiders, scorpions, and myriapods. A greater incidence of snake bites occurred in northern Spain, but no geographical trends were found for spider bites or scorpion stings. Severe poisoning or life-threatening cases due to bites or stings from toxic terrestrial animals in Spain seems to be very low, especially for spiders, compared to other countries in the world. In general, spiders do not present a risk to human health and should not be considered a major driver of morbidity.

Brown spiders (Loxosceles) are taking hold in Pernambuco, Brazil: a case series, 2018-2022.

OBJECTIVE: To describe accidents involving brown spider (genus Loxosceles) bites notified by the Pernambuco Poison Information and Care Center (CIATox-PE), Brazil, from January 2018 to December 2022. METHODS: This was a case series study of brown spider bites notified by the CIATox-PE. RESULTS: The study included 22 cases with median age of 35 years, the majority being female (13); the cases occurred in rural and urban areas (12 versus 10), at night (10); Petrolina was the municipality with the highest number of notifications (6); spider bites occurred mainly in the lower (11) and upper (9) limbs, almost exclusively inside households (21); specific serum therapy was not indicated for 8 cases because the time for its effectiveness had already elapsed. CONCLUSION: Loxoscelism cases occurred more frequently in females, in both rural and urban areas and mainly at home, with delays in seeking medical care. MAIN RESULTS: The 22 cases described represent an alert for the presence of a venomous species not reported in previous studies in Pernambuco. The severity of cases may be associated with delays in seeking medical care, especially due to the population's lack of information. IMPLICATIONS FOR SERVICES: Identify the presence of brown spiders in households in the region and the potential severity of poisonings. Alert health professionals to recognize the clinical picture with a view to appropriate early treatment. PERSPECTIVES: Develop research on poisoning by venomous animals and educational actions alerting the population to prevent these accidents and updating health professionals on care.

Does Covid-19 influence the dynamics of envenomation by animals in a country strongly affected by both conditions? Epidemiological data from Brazil.

The impact of Covid-19 on envenomations by venomous animals in countries heavily affected by both conditions has not been quantified yet. Brazil shows high incidence of envenomations by scorpions, spiders and snakes and was heavily affected by waves of Covid-19. To determine how the pandemic impacted the epidemiology of envenomations by those three groups of venomous animals, we used online databases from two surveillance sources on number of cases and mortality. During the years before and during the pandemic, scorpion stings typically occurred in adults of both sexes in urban zones in the Southeast and Northeast regions. Spider bites occurred mainly in the South region, in adults of both sexes in urban zone. Snakebites affected mainly rural adult men in the Amazon. Between 2007 and 2021, overall incidence of cases by scorpions, spiders and snakes decreased after the beginning of the pandemic, snakebites did not show changes after the pandemic started in Brazil, but cases by scorpions and spiders decreased. No changes in the incidence of deaths were observed. On national level, Covid-19 affected some demographic, clinical and epidemiological aspects in cases by scorpions, spiders and snakes.

Spider bite.

Spiders are a source of intrigue and fear, and several myths exist about their medical effects. Many people believe that bites from various spider species cause necrotic ulceration, despite evidence that most suspected cases of necrotic arachnidism are caused by something other than a spider bite. Latrodectism and loxoscelism are the most important clinical syndromes resulting from spider bite. Latrodectism results from bites by widow spiders (Latrodectus spp) and causes local, regional, or generalised pain associated with non-specific symptoms and autonomic effects. Loxoscelism is caused by Loxosceles spp, and the cutaneous form manifests as pain and erythema that can develop into a necrotic ulcer. Systemic loxoscelism is characterised by intravascular haemolysis and renal failure on occasion. Other important spiders include the Australian funnel-web spider (Atrax spp and Hadronyche spp) and the armed spider (Phoneutria spp) from Brazil. Antivenoms are an important treatment for spider envenomation but have been less successful than have those for snake envenomation, with concerns about their effectiveness for both latrodectism and loxoscelism.

Redback spider bites in children in South Australia: A 10-year review of antivenom effectiveness.

OBJECTIVE: To describe the South Australian paediatric redback spider bite experience and to examine the hypothesis that redback antivenom (RBAV) treatment in children is clinically effective. METHODS: Retrospective chart review of all children under 18 years of age presenting to the EDs of the three major paediatric or mixed hospitals in Adelaide, South Australia, with a discharge diagnosis of redback spider envenomation between 1 January 2010 and 31 March 2020. The main outcome measures include: patient and bite demographics; presenting symptoms and signs; treatment provided; clinical effects at 2 h post RBAV administration on pain, diaphoresis, blood pressure, heart rate and systemic features; overall clinical impression of RBAV effectiveness and resolution of symptoms prior to discharge. RESULTS: There were 256 patient encounters involving 235 patients. Latrodectism was described in one-third (34%) of the cases. Sixty-one patients received RBAV and in 57 (93%) patients the RBAV had good clinical effect. Two hours post RBAV administration, pain resolved in 71%, hypertension resolved in 62%, diaphoresis resolved in 43% and tachycardia resolved in 82%. There were no cases of urticaria or anaphylaxis and one case of serum sickness. CONCLUSIONS: This retrospective review of redback spider envenomation in South Australian children over a 10-year period has demonstrated clinical effectiveness of RBAV in paediatric patients across all age groups, observed in both clinician perceived results and measurable outcomes. RBAV remains an effective treatment for redback envenomation in children.

"Spider bite" lesions are usually diagnosed as skin and soft-tissue infections.

BACKGROUND: Many people seek medical attention for skin lesions and other conditions they attribute to spider bites. Prior experience suggests that many of these lesions have alternate causes, especially infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). OBJECTIVES: This study determined the percentage of emergency department (ED) patients reporting a "spider bite" who received a clinical diagnosis of spider bite by their physician vs. other etiologies, and if the diagnoses correlated with demographic risk factors for developing CA-MRSA infections. METHODS: ED patients who reported that their condition was caused by a "spider bite" were prospectively enrolled in an anonymous, voluntary survey regarding details of their illness and demographic information. Discharge diagnoses were also collected and categorized as: spider bite, bite from other animal (including unknown arthropod), infection, or other diagnosis. RESULTS: There were 182 patients enrolled over 23 months. Seven patients (3.8%) were diagnosed with actual spider bites, 9 patients (4.9%) with bites from other animals, 156 patients (85.7%) with infections, and 6 patients (3.3%) were given other diagnoses. Four patients were given concurrent diagnoses in two categories, and 8 (4.4%) did not have the diagnosis recorded on the data collection instrument. No statistically significant associations were found between the patients' diagnostic categories and the demographic risk factors for CA-MRSA assessed. CONCLUSION: ED patients reporting a "spider bite" were most frequently diagnosed with skin and soft-tissue infections. Clinically confirmed spider bites were rare, and were caused by black widow spiders when the species could be identified.

Love bites - Do venomous arachnids make safe pets?

With a global estimate of tens of thousands of arachnid enthusiasts, spiders and scorpions are gaining increasing popularity as pets in industrialised countries in Europe, Northern America and Asia. As most spiders and all scorpions are venomous and due to their mostly negative image in the public media, several governments are already considering introducing legislation to regulate the domestic care of potentially dangerous captive animals. We aimed to investigate the circumstances and effects of exposure to arachnids kept in captivity. Thus, we collected and analysed data from 354 self-reported bites and stings attributed to pet arachnids. Our data revealed that on average there were less than 20 recorded envenomations per year with ~90% preventable by due care. We also categorized the severity of the resulting symptoms and found that the vast majority of symptoms were either local (60.7%) or minor (32.8%), 5.4% were asymptomatic, only 1.1% were severe and no fatalities were recorded. Based on our database of bite and sting reports, we performed a risk assessment for arachnid pet ownership and concluded that, with the proper care, arachnids can be safely kept as pets and pose a lower risk than many other recreational activities.

A case of pediatric northern black widow spider (Latrodectus variolus) bite in New York, USA.

Black widow spiders (Latrodectus spp.) are generally perceived as inhabiting southern or western United States. However, some species, such as the northern black widow, Latrodectus variolus, are also found in more temperate regions of USA and adjacent Canada. This species also appears to expand its range northward with the climate change increasing the risk of human encounters. To our knowledge, this is the first case report of a pediatric envenomation from a northern black widow bite in northeastern US. Medical practitioners often fail to recognize the signs and symptoms of latrodectism delaying effective treatment. Even in more northern locales, healthcare workers should take black widow spider envenomation under consideration in the differential diagnosis particularly with suspected exposure.

A Review of Black Widow (Araneae: Theridiidae) Envenomation, Epidemiology, and Antivenom Utilization in Canada.

Two species of black widow spider (BWS-Latrodectus hesperus Chamberlin & Ivie and Latrodectus variolus Walckenaer) naturally occur in Canada and are capable of causing deleterious envenomation to humans. No Canadian literature exists on the frequency of envenomations by these species or the use of antivenom in the treatment of those patients. A review of primary Canadian arachnology data was undertaken to identify BWS populations. A retrospective review of the Health Canada Special Access Program records generated epidemiology and the utilization of antivenom for BWS envenomations in Canada. The geographical distribution of BWS species is limited to along the southern Canadian border. From January 2009 to December 2015, there were five BWS envenomations that required treatment with antivenom and all cases occurred in British Columbia. An average patient age of 41 yr ± 21 SD (range 7-59) was observed, along with three of the five patients being female. The average number of vials used for treatment was 2 ± 1 SD (range 1-3). BWS Antivenin was also obtained by facilities in Alberta, Ontario, and Nova Scotia, but not used in any of these jurisdictions. Further investigation is necessary to determine the annual incidence of BWS envenomations and if treatment with BWS antivenin is required.

Venomous Snake and Spider Bites in Pregnancy.

IMPORTANCE: Venomous snake and spider bites are relatively rare in the Unites States and even more so in the pregnant population. However, the impact of a venomous bite, also known as an envenomation, can be serious in a pregnant patient. Thus, providers in endemic and high-risk areas must be familiar with the management of envenomation in the pregnant population. OBJECTIVE: The purpose of this article is to review the current literature on the most common snake and spider envenomations in the United States, the effects of envenomation on maternal and fetal health, and the management of envenomation in pregnancy. EVIDENCE ACQUISITION: Original research articles, review articles, and guidelines on snake and spider envenomation were reviewed. RESULTS: Snake envenomation carries higher risks of maternal morbidity and fetal morbidity and mortality than spider envenomation. Although the data are limited, current literature suggests that both snake and spider antivenom can be used in the pregnant population without significant adverse outcomes. However, the risks of an adverse hypersensitivity reaction with antivenom administration should be weighed carefully with the benefits. CONCLUSIONS AND RELEVANCE: The use of antivenom therapy in the symptomatic envenomated pregnant population is likely safe with the appropriate monitoring and follow-up. Knowledge of the indications for antivenom therapy and proper escalation of care are vital to optimizing maternal and fetal outcomes. More research is needed to determine the effects of both envenomation and antivenom therapy on the pregnant patient and their fetus.