# The frequency, clinical characteristics and outcomes of Naja species related injuries in Malaysia consulted to Remote Envenomation Consultancy Services from 2020–2023

## TL;DR

This study analyzed over 500 cobra bite cases in Malaysia from 2020–2023, revealing common symptoms, treatment delays, and the importance of expert guidance to improve outcomes.

## Contribution

The study provides the first comprehensive analysis of Naja species envenomation in Malaysia using a large, real-world dataset from a remote consultancy service.

## Key findings

- Naja kaouthia cases were concentrated in northern and central Malaysia, while Naja sumatrana was found nationwide.
- Local envenomation was the most common manifestation, with pain and swelling as primary symptoms.
- Four deaths occurred due to secondary complications, and antivenom was administered in 30.7% of cases.

## Abstract

Naja species bites and envenomation are common in Malaysia. This is a retrospective cohort study of diagnosed Naja species cases consulted to Remote Envenomation Consultancy Services (RECS) from 2020 to 2023. This study aimed to identify the frequency, geographical distribution, clinical features, treatments, and outcomes of Naja species-related injuries. Data was extracted following the approval of the institutional research ethics committee and all patient’s information were kept anonymous. From 4474 RECS consultations, 512 were diagnosed as caused by Naja species. Naja kaouthia cases were mostly from the northern and central Peninsular Malaysia, while Naja sumatrana was recorded nationwide. There were 184 (35.9%) cases diagnosed as undifferentiated Naja species bites, 144 (28.1%) N. sumatrana bites, 121 (23.6%) N. kaouthia bites, 61 (11.9%) venom ophthalmia and 2 (0.4%) involved bites and venom ophthalmia from N. sumatrana. The mean age was 36.2 years old (SD ± 20.7), and 69.9% were male. The median bite to door time was 1 h (IQR: 0–2 h). The most frequent anatomical region involved was the lower limb (52.1%). Local envenomation is the commonest manifestation (n = 366, 81.2%). Pain (n = 386) and swelling (n = 310) were frequent signs of local envenomation, while vomiting (n = 54) and ptosis (n = 37) were commonest signs of systemic envenoming. Antivenom was administered in 157 (30.7%) cases and 78.3% were Thai Red Cross Cobra antivenom. The median time interval for door to receiving the first dose of antivenom was 12 h (IQR: 5.5-14.5 h). Surgical intervention was performed in 53 (11.8%) cases, mostly were for wound debridement. Four deaths were documented and were due to secondary complications. No antivenom usage, morbidity or death following venom ophthalmia incident. These findings highlight the importance of expert support for healthcare professionals for early clinical decision-making to reduce complications and enhance outcomes.

Cobra bites in Malaysia are common but rarely studied. The study included over 500 cases of bite injuries caused by Naja species across a 4-year period. It reported on the frequency, symptoms, treatment, and outcomes. Naja sumatrana and Naja kaouthia were the two cobra species indigenous to Malaysia, with different geographical distribution in the country. Most of the diagnosis were classified as undifferentiated Naja species based on the clinical features. The median time of bite to arrival at a healthcare facility was 1 h. The lower limb was the most common part of the body involved with pain and swelling, being the most common local symptoms. Local envenomation had better prognosis than systemic envenomation. Antivenom was utilized in 30.7% of cases with the median door to first antivenom was 12 h. Four deaths were reported throughout the study period. This study highlights the importance of adhering to the national guidelines for snakebite envenomation management supported by consultations from experts in the field for optimal care and outcome.