Snakebite in Saudi Arabia: A public health risk needs to be re-visited

Ahmed Salah Eldin Gouda; Bandar Saeed Al Balwi; Fadi Ibrahim Alanazi; Sulaiman Timah Alanazi; Khalaf Alwan Al-Enezi

doi:10.4103/sjfms.sjfms_5_20

REVIEW ARTICLE

Year : 2019 | Volume : 2 | Issue : 2 | Page : 21-27

Snakebite in Saudi Arabia: A public health risk needs to be re-visited

Ahmed Salah Eldin Gouda¹, Bandar Saeed Al Balwi², Fadi Ibrahim Alanazi³, Sulaiman Timah Alanazi⁴, Khalaf Alwan Al-Enezi⁴
¹ National Egyptian Center for Toxicological Researches, Faculty of Medicine, Cairo University, Giza, Egypt; Poison Control and Forensic Chemistry Center, Northern Borders Directorate of Health Affairs, Ministry of Health, Saudi Arabia
² Department of Inventory control Tabuk Directorate of Health Affairs, Ministry of Health, Saudi Arabia
³ Regional Laboratory, Northern Borders Directorate of Health Affairs, Ministry of Health, Saudi Arabia
⁴ Poison Control and Forensic Chemistry Center, Northern Borders Directorate of Health Affairs, Ministry of Health, Saudi Arabia

Date of Submission	06-Aug-2020
Date of Decision	16-Aug-2020
Date of Acceptance	10-Sep-2020
Date of Web Publication	13-Feb-2021

Correspondence Address:
Ahmed Salah Eldin Gouda
6771 Makkah Street, Mansouria, Arar

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sjfms.sjfms_5_20

Abstract

Snakebite envenoming is a neglected tropical disease causing a global public health risk. The real magnitude of this risk in Saudi Arabia could not be fully identified, together with the reported prevalence of highly venomous snakes. This study reviews the reported prevalence, clinical manifestations, and treatment plans of local snakebite victims from the published data on the main electronic databases in the last 20 years. The search resulted in a total of nine studies. All the included published studies collected their data within the time frame from 1983 to 2010, and located in only four governments of Saudi Arabia. The most common snakes identified were Cerastes cerastes and Echis coloratus, and most of the included cases showed coagulopathy. Different types of antivenom were used in the included studies with no stated treatment protocol. Our study concluded that there is a necessity for approaching a nation-wide survey study on the prevalence of snakebite injury with generalization of an evidence-based treatment protocol for management of snakebite victims.

Keywords: Antivenom, Elapidae, Saudi Arabia, snakebite, Viperidae

How to cite this article:
Eldin Gouda AS, Al Balwi BS, Alanazi FI, Alanazi ST, Al-Enezi KA. Snakebite in Saudi Arabia: A public health risk needs to be re-visited. Saudi J Forensic Med Sci 2019;2:21-7

How to cite this URL:
Eldin Gouda AS, Al Balwi BS, Alanazi FI, Alanazi ST, Al-Enezi KA. Snakebite in Saudi Arabia: A public health risk needs to be re-visited. Saudi J Forensic Med Sci [serial online] 2019 [cited 2023 Mar 22];2:21-7. Available from: https://www.sjfms.org/text.asp?2019/2/2/21/309347

Introduction

Venomous snakes are prevalent worldwide, and related bites are considered a significant public health risk of morbidity and mortality.^[1] Data available globally showed about 4.5–5.4 million snakebite victims with 81,000–138,000 mortality reported annually.^[2] Moreover, the real global impact of snakebites is mostly underestimated due to limited reliable epidemiological and clinical data.^[3] The World Health Organization (WHO) enlisted snakebite envenoming as a neglected tropical disease,^[4] and snakebite is one of the highly fatal diseases in this list.^[5] In 2019, the WHO planned a global strategy that aims to decrease snakebite-related death and disability.^[4] As for Saudi Arabia, some studies reviewed the epidemiological snake distribution and snakebite risks of local venomous snakes, but these studies failed to identify the real magnitude of that risk due to deficient enough original data.^[6],[7],[8]

Averagely 3000 snake species are present world widely, of which about 375 are venomous.^[9] Venomous snakes are known to be classified to mainly the following four families: Viperidae, Elapidae, Atractaspididae, and Hydrophidae.^[10],[11] Snake species are inconsistent with each other in different geographical areas and also the effect of venom varies geographically in the same species and can be influenced by environmental factors such as humidity and temperature.^[12]

More than ten highly venomous snake species have been reported to be present in Saudi Arabia.^[8] Venomous snake species that were reported to be present in Saudi Arabia belong to different families, such as Viperidae (Bitis arietans, Cerastes cerastes, Cerastes gasperettii, Echis borkini, Echis coloratus günther, Echis carinatus, and Pseudocerastes fieldi), Elapidae (Walterinnesia morgana, Naja arabica, and Walterinnesia aegyptia), and Atractaspididae (Atractaspis andersonii and Atractaspis engaddensis).^{[6],[13],[14]}

Although different protocols are available to treat snakebite,^{[15],[16],[17]} there is a difficulty in recommending a universal protocol.^[18],[19] Furthermore, adopting a treatment protocol with approved efficiency from other demographic area may not prove adequate efficiency because of the demographic and antivenom (AV) variability.^[19],[20]

As inadequate knowledge of effective treatment protocol for snakebites may lead to increase in mortality.^[21] Many authors, countries, and entities recommended treatment protocols designated for defined regional snakebite. These protocols were formulated from available clinical information, and the authors recommended to publish them among local health-care workers.^{[19],[22],[23],[24],[25],[26]}

Aim of the study

In Saudi Arabia, snakebite is considered a local health problem in some areas.^[27] The current article aims to provide a review on the prevalence, the common clinical manifestations, and the treatment plans of local snakebites in Saudi Arabia.

Methods

This is a retrospective review study on the available published local clinical data concerning snakebites in Saudi Arabia to assess the available published information concerning prevalence, types, clinical picture, and treatment of local snakebites.

Data gathering and study selection

Data were extracted through searching the following main electronic databases MEDLINE (via PubMed) and Google Scholar from January 1990 to July 2020 for clinical observational studies and randomized controlled trials addressing snakebites in Saudi Arabia. We searched using the following keywords “snakebite” and “snake envenomation” and cross-referenced with the word “Saudi” to collect all studies addressing the local snakebite cases, clinical data on victims, and therapeutic approaches (using Medline MeSH database [”Snake Bites”(Mesh)] AND “Saudi Arabia”(Mesh), and Google Scholar advanced search [Snakebite AND Saudi Arabia AND clinical]). Eligible articles' titles were scanned and the full-texts were obtained and studied. Studies that did not meet the selection criteria were excluded. Two reviewers (AS and BA) performed the search and selection procedures independently and disagreements were resolved by discussion with a third reviewer (KA) who was acting as an arbiter [Figure 1]. The full text was obtained for all of the included studies.

Figure 1: Flow diagram of the process of article selection

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Eligibility criteria for study inclusion

Inclusion criteria

All studies which include clinical manifestations or treatment of local snakebite victims in Saudi Arabia
We included studies that meet all the following criteria:

Population – Involving any snakebite victims in Saudi Arabia irrespective of origin, age, gender, or any other characteristics
Disease condition – Any case of snakebite irrespective of the severity of clinical manifestations
Study findings – Descriptive studies reporting the prevalence, clinical manifestation of the snakebite victims, treatment protocol, and prognosis.

Study design

Cohort studies (prospective or retrospective)
Cross-sectional studies
Case studies.

Exclusion criteria

Nonconformance to inclusion criteria
Nonclinical studies
Environmental studies
All studies published prior to 1990 were excluded.

Data extraction

Type of the study
Data-gathering method, place, and period
Publication journal and year
Number of cases
Target population
Identified snakes
Reported clinical manifestation
Reported treatment.

Results

A total of 1168 records were identified through database search by two reviewers: Medline (8) and Google Scholar (1160). After removing duplicates and excluding articles that did not fulfill the selection criteria, the search resulted in a total of nine references that matched the predefined selection criteria.

Characteristics of the included studies

Of the nine articles included, six were retrospective studies,^{[28],[29],[30],[31],[32],[33]} two were case reports,^[27],[34] and one was a prospective surveillance study.^[35] Except for one case study which was published in 2014,^[34] all the published studies collected their data between 1983 and 2010. All these included studies reported 1265 snakebite victims through 31 years (from 1983 to 2014).

As for the target study area, three studies were in Riyadh,^{[28],[32],[34]} four in Asir,^{[27],[30],[31],[33]} one in Al-Baha,^[29] and one in Hail.^[35] Concerning target population, four studies targeted all age ranges of snakebite victims,^{[29],[30],[32],[35]} two targeted only adults over 12 years old,^[28],[33] one targeted children,^[31] and the two case studies showed adult patients.^[27],[34] Only three of the studies collected data from all the regions' health-care facilities,^{[32],[33],[35]} while the rest were only a hospital experience. [Table 1] shows an overview of the included studies' characteristics.

Table 1: An overview of the included studies' characteristics

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Snake identification was feasible for some cases in six of the included studies, either from patient's description or from bringing dead snake to the health-care facilities. Viperidae family was the most common to be identified (C. cerastes, Echis coloratus, and B. arietans).^{[28],[32],[35]} Another snake identified was Malpolon moilensis which belongs to the family of Lamprophiidae.^[35] Elapidae snake (namely W. aegyptia) was also identified in one case.^[35] Only one of the studies targeted single-species (E. coloratus) bite victims,^[31] while the rest collected the presented snakebite victims irrespective of the snake species.

Eight studies reported clinical manifestations of the included snakebite victims. Apart from local pain and swelling, which was prevalent in most cases, coagulopathy was the most prevalent systemic toxic manifestation (66.7% of patients in one study).^[28] Local ecchymosis, compartment syndrome, and renal affection were noticeable in many cases. Neurotoxicity was not recorded except in one patient in one study.^[29]

Different types of equine polyvalent snake AV were reported to be used to treat patients, namely Pasteur (anti-Bitis-Echis-Naja),^{[28],[29],[31]} Behring (antisnake serum for the near Middle East; Marburg, Germany),^[27],[30] and local equine polyvalent antisnake venom (ASV) (the Antivenom and Vaccine Production Center, National Guard Health Affairs, Riyadh, Saudi Arabia).^[32]

Most studies did not report the protocol used for AV dosage, frequency, or precautions. Meanwhile, some studies reported the performance of skin hypersensitivity testing prior to injection of AV.^{[30],[31],[35]} Other studies reported the usage of fresh frozen plasma (FFP) to some cases without reporting its indication.^{[27],[28],[29],[34]} [Table 2] shows an overview of the included studies' results.

Table 2: An overview of the included studies' results

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Discussion

The included published local researches handling the clinical state of snakebite victims are scarce (nine researches in the last 20 years), and most of these studies collected their data in between 1983 and 2010 with no recent related published cohort or observational studies concerning snakebite victims in the last 10 years. Moreover, the included researches only targeted three regions (Riyadh, Asir, and Hail) of the Kingdom of Saudi Arabia, which is the largest nation in the Arabian peninsula containing 13 vast regions divided into 118 governorates with diverse demographic characteristics.^[36],[37] All of the collected data were insufficient to provide any pooled estimates or analysis. This corresponds to Al-sadoon's study which stated that snakebite data in Saudi Arabia are insufficient and fragmentary.^[32] This agrees also with other studies that concluded that snakebite is a risk to public health, which needs to be identified and controlled.^[28],[32]

Adding to that, most of the included studies reviewed a single hospital experience of snake bite victims. This cannot express the real burden of snakebite risk to the target area. Many snakebite victims die before reaching health-care facilities because of geographical or economic constraints. Moreover, there are social, cultural, or spiritual beliefs that affect public perception of snakebite envenoming, affecting their chance of seeking medical treatment.^[4] In India and Nepal, more than 75% of snakebite-related mortalities occur outside the hospital setting.^[38]

The toxic effect of venomous snakes varies: Viperidae family mainly has hemotoxic venom, whereas Elapidae family mainly has neurotoxic venom.^[39] Severe Viperidae envenoming commonly presents with coagulopathy,^[40],[41] whereas severe Elapidae envenoming commonly presents with neurotoxicity.^[42],[43] Studies show that Viperidae was the most common snake family identified from snakebite victims, which is in accordance with the most prevalent toxic manifestation reported which is coagulopathy. Renal affection was also noted in most of the included studies, which corresponds to the reported renal affection that occurs with C. cerastes and E. coloratus.^{[44],[45],[46]} Meanwhile, Elapidae snakes were identified in one case in all of the included studies, which justifies the absence of neurological manifestations except in one case in the same study. These results show that Viperidae snakes (mainly C. cerastes, and E. coloratus) are the most prevalent snakes in Saudi Arabia.

The results of the current study show that most local studies used polyvalent AV (Pasteur anti-Bitis-Echis-Naja) till 2005, although they did not refer to the exact type of AV used (FAV Africa or FAVIPERT). Pasteur snake AVs, equine immunoglobulin F(ab')2 AVs, has three product types, namely, (1) FAV Africa (polyvalent for Bitis, Echis, Naja, and Dendroaspis), (2) Favirept^® (polyvalent for Bitis, Echis, Naja, Cerastes, and Macrovipera), and (3) VIPERFAV (polyvalent for vipera).^[47] FAV Africa, being deficient in anti-cerastes sera, would be not suitable as cerastes is one of the most prevalent snakes. Two studies that collected their data in the same time period reported using different types of anti-snake venom (Behring's polyvalent snake AV and Pasteur AV). This indicates that there was no set standard local protocol for the management of local snakebites at that time period. The most recent study^[32] showed equine polyvalent ASV was used (the Antivenom and Vaccine Production Center, National Guard Health Affairs, Riyadh, Saudi Arabia) from 2005. This AV is a F(ab)2 fraction of the immunoglobulin against six local Saudi snakes, namely B arietans, C cerastes, E carinatus, E coloratus, N haje, and W aegyptia.^[14]

AV efficacy is known to vary widely due to many factors, mainly including appropriate type, dose, and indication.^[48] In addition, the AV efficacy varies from batch to batch,^[24] with the possibility of delayed effect even when using appropriate AVs.^[25] All the mentioned factors affecting efficacy together with the possibilities of different types of early and late adverse reactions from AVs^[24] necessitate more descriptive studies on the efficacy of AV used in treatment.

All the included studies described the variable types of AV used with no referral to the protocol used for administration dosage, frequency, or safety, of any. This contradicts with some studies that recommended the usage of a specific local snakebite treatment protocol to each region due to demographic and AV variability.^[23] In 2016, the Kingdom of Saudi Arabia published a local protocol for the management of snakebite victims.^[49] Meanwhile, there have been no studies published afterward to assess the efficacy of the treatment protocol. Moreover, the published protocol stated that the most common snakes in Saudi Arabia are N. haje and W. aegyptia. This contradicts with the available data which indicate that C. cerastes and E. coloratus are the most reported venomous snakes. In 2019, the WHO published a global strategy to decrease snakebite-related mortality and disability by 50% before 2030. One of these strategies aims to ensure safe, effective treatment and setting effective prevention and management plans into national health systems and national policies.^[4]

Skin sensitivity test for AVs was done in some of the included studies,^{[30],[31],[35]} and it is recommended by the local protocol of management.^[49] Meanwhile, this test is not recommended to be done for snake AV by the WHO as it may be sensitizing and delaying treatment.^[24] FFP was also used in some patients with no referral of the indication of administration.

Conclusion

Although Saudi Arabia is the largest nation in Arab peninsula and a local prevalence of highly venomous snakes was reported, published studies related to snakebite victims in Saudi Arabia are infrequent, outdated, and not integral. Viperidae snakes were the most common causative organism for snakebites reported. There is no available evaluation of the current AV efficacy. Moreover, there is no available evaluation of the published local protocol for medical management of snakebites.

Recommendations

Local nationwide survey studies on the prevalence of snakebite injury in different Saudi regions
Publishing an evidence-based treatment protocol for the management of snakebite victims to all local health-care facilities, together with the training of health-care staff
Assessing the efficacy of the treatment protocol and AV used through clinical studies.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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