A Study of the Pattern of Injuries Sustained from Road Traffic Accidents Caused by Impact with Stray Animals

Abstract

Background:

The incidence of road traffic accidents (RTA) is increasing every day, especially in developing nations. Amongst various attributable factors, the menace of the stray animals remains one of the most underrecognized factors leading to animal-vehicle collision (AVC). Objectives: Our prospective cross-sectional study aims to survey the incidence of RTA attributable to stray animals and record the pattern of injuries along with other epidemiological parameters.

Methods:

The present study was conducted at a tertiary care trauma centre located in a major city of eastern India, between June 2019 and March 2020. Variables like demographic details, type of vehicle and injury with severity score, use of safety gear including types of stray animals were collected and analysed.

Results:

A total of 185 patients had suffered RTA due to AVC during the study period. The median age of occurrence was 29.0 years. The evening was the most frequent time of accidents (4 PM to 8 PM) with two-wheelers affected in 92% of cases. Stray dogs account for 69% of cases followed by cattle 21% cases. 41% of all RTA victims had polytrauma. Patients with RTA due to impact with ox were found to have higher injury severity score (ISS). The ISS comparison between two-wheeler drivers with and without helmet and influence of alcohol were statistically significant (P<0.01).

Conclusion:

The study highlights an alarming incidence of RTA due to stray animals roaming freely on roads, thus adding significant morbidity and costs to the society. There is a need of the hour for imposing stringent measures from the appropriate authority, including public awareness to make sustainable action plans to prevent animal homelessness and wander freely on streets and major roads.

INTRODUCTION

Road traffic accidents (RTA) are a significant public health problem globally and more so in a developing country like India with a growing number of vehicles and road network.[1] Of the several factors implicated for their cause, the menace of the stray animals remains one of the most underrecognized factors causing harm both to the human and to the animals.[2,3] In our country, the vagrant animals wander freely on the roads and thus pose a constant threat to the commuters both in a rural and in a urban setup. The two-wheelers are most at risk, but no motorized vehicles or pedestrians are left safe to their intimidation. The common stray animals causing traffic bottlenecks include dogs and cattle.[4] In most instance, an animal–vehicle collision (AVC) causes injury, but sometimes victims suffer due to imbalance of vehicles in an attempt to avoid the animals. Patients present with various patterns of injury that lie in the spectrum between a simple soft tissue injury (STI) to the grievous organ injuries and even polytrauma. However, there is a paucity of data worldwide in regard to the epidemiology of injuries caused by RTA due to AVC though this is now recognized as an important issue for socioeconomic costs.[5,6]

This prospective, cross-sectional study, conducted at our tertiary care trauma center located in a major city of eastern India, is to survey the incidence of RTA due to stray animals and record the pattern of injuries along with other epidemiological parameters.

MATERIALS AND METHODS

Study design

This prospective, observational study was performed in the Department of Trauma and Emergency (T and E) of the premier institute of Eastern India from June 2019 to March 2020. The approval was taken from the institutional ethics committee (IEC Ref No T/IMNF/T and EM/18/72 11/04/2019), and the study was registered with the Clinical Trial Registry of India (CTRI-CTRI/2019/05/019317).

Participants

All RTA patients due to impact with stray animals attending to T and E of our institute for 9 months (June 3 2019–March 1, 2020) were included in the study. Patients who failed to give consent and refused to participate in the study and trauma patients due to the direct attack of animals were excluded from the study.

Data collection and variables

Victims of RTA involving animal impact admitted to the tertiary care trauma center were enrolled in the study after due consent of the patient or the accompanying caregiver. Consecutive sampling was done with all eligible participants to create an unbiased environment for the study. Information including basic demographic features, place and circumstances of the injury, details of prehospital interventions if any, and type and mechanism of injury was recorded in a predesigned pro forma. All patients were evaluated as per the ATLS guidelines.

Demographic variables entered included age, sex, type of vehicle involved in the accident, speed of the vehicle, time of injury, time of arrival, mode of arrival to T and E, and type of victim (driver and pillion rider). The use of safety gears (helmets/seatbelts) and alcohol consumption were also noted. Clinical injuries were classified as head injury, maxillofacial injury, chest injury, abdominal injury, extremity injury, and STIs. The severity of the injury was calculated using the injury severity score (ISS). The type of impact in AVC was categorized as front impact, side impact, rear impact, and rollover. The severity of the impact was categorized as low-impact AVC (ISS ≤15) and high-impact AVC (ISS >15).

Study size

Two hundred and five patients were recruited for the study, and after excluding twenty patients, 185 patients were included in the study for analysis.

Statistical methods

Statistical analysis was performed by using R, a software environment for statistical computing and graphics (version 3.6.1; Vienna, Austria). Numerical variables (nonparametric) were expressed as a median with interquartile range (IQR). Categorical variables were expressed as a percentage. Bivariate analysis between categorical variables performed by the Chi-square test. The normality of numerical variables analysed by the Shapiro-Wilks test. Bivariate analysis between categorical and numeric variables performed using the Wilcoxon rank-sum test with continuity correction comparing two groups and Kruskal–Wallis rank-sum test comparing more than two groups. P < 0.05 was considered statistically significant.

RESULTS

The flow diagram of the subjects in the study is depicted in Figure 1. A total of 205 patients were recruited for the study; however, after excluding 20 patients, 185 patients were included in the study for analysis. The median age of the patients was 29.00 years (20.00–41.00) [1.00–69.00] (IQR) [Range]. The gender distribution M: F was 82:18. The mode of transportation to T and E was ambulance (58%), police control room van (8%), self-transportation (6%), and other private vehicles (26%). Forty-five (22%) patients reached the T and E within the golden hour (first 1 h). Evening time (23%) was the most common time of accidents (4 PM to 8 PM), followed by noon (12 PM to 4 PM) as shown in Figure 2. Analysis of vehicle involved in RTA revealed two-wheelers in 92%, three-wheelers in 5%, and other vehicles in 3% cases. Eighty percent of total victims were drivers, and 20% were pillion riders or occupants of the vehicle.

Figure 1.

Flow diagram of the subjects in the study

Figure 2.

Bar diagram showing the time of injury of patients

The ISS of all patients was 13 (9–18) [4–43]; median (IQR)[Range]. Forty-nine per cent of all RTA victims had polytrauma (ISS > 15). Stray dogs accounted for 69%, cattle 21%, ox 5%, and other animals in 5% of impact with the vehicles. The distribution of injury severity due to different types of animal impact is depicted in the violin plot [Figure 3]. The ISS between different types of animals was not statistically significant (P = 0.35, Kruskal–Wallis rank-sum test). However, patients with RTA due to impact with ox were found to have higher ISS and polytrauma. The severity of impact categorized as low- and high-impact collision and the distribution of severity of impact between different types of animals are shown in Figure 4. Fifty-one percent of AVCs were low impact, and 49% were high impact. Ox and cattle were involved in a higher percentage of high-impact AVC. The type of impact between animal and vehicle was the front impact (41%), side impact (49%), rear impact (3%), and rollover (7%) of all AVCs. The speed of vehicle involved in AVC was categorized as speed < 40 kmph (23%), 40–60 kmph (32%), >60 kmph (38%), and cannot tell about speed (7%). Fourteen percent of all victims were found to be under the influence of alcohol. Only 31% of occupants of two-wheeler wear helmet. The pattern of injury among victims is shown in Figure 5. The radiological findings, emergency procedures in T and E, and the outcomes of patients are shown in Table 1.

Figure 3.

Violin plot showing the distribution of injury severity with different types of animals

Figure 4.

Bar diagram showing the severity of impact due to animal–vehicle collision

Figure 5.

Bar diagram depicting the injury pattern among victims

Table 1.

Radiological findings, emergency procedures, and outcome of patients due to animal–vehicle collision

Variable	Class	Percentage
1 X ray findings	Normal	65
	Upper extremity fracture	27
	lower extremity fracture	11
	Ribs fracture	6
	Clavicle fracture	5
	Scapula fracture	1.5
	Pelvis fracture	1
2 CT Scan findings	Normal	59
	Maxillofacial fracture	40
	Brain contusion	25
	Diffuse axonal injury	4
	Spine fracture	0.5
3 FAST (ultrasonography)	positive	3
4 Procedures	Suturing and Dressing	40
	Cast / Splint Application	52
	Rapid sequence Intubation	3.2
	Chest tube insertion	2.7
5 Outcome	Discharged after(treatment/observation)	66
	Admitted to indoor	26
	Admitted to ICU	4
	Referred	2

FAST= Focused assessment with sonography for trauma, ICU= Intensive care unit

DISCUSSION

India tops the list of global fatalities and injuries from the road crashes with an estimated burden of more than 550 billion rupees, which is whooping 3% of our gross domestic product of the country.[7] Ironically, the affected victims mainly belong to the prime productive age group. It is not just the traffic rule violations or bad roads but menace of the stray animals, namely, the canines and cattle that have become a potential threat for commuters in almost every city of our country. A report from a single city, Mysore, estimates about 20,000 stray cattle and 40,000 dogs on the road.[4] Stray animals cause 10% of overall accidents in Bhopal's roads.[3] The figures may not be very different in the city of Bhubaneswar. The number of RTA involving these vagrant animals has reached a worrying proportion; hence, a specific targeted study and statistics is the need of the hour.

The majority of the victims were male (84%). This is consistent with almost all reports on epidemiology of RTA victims in our country and elsewhere.[8,9] In our country, the majority of two-wheeler drivers are males. Again, the majority of the victims are young, that is, consistent with the literature.[8,9,10] The younger population has a greater association with the two-wheelers that are potentially unstable, especially in an emergent condition such as bumping into an animal. The injury pattern is of wide range, but higher ISS was noted among the victims riding under the influence of alcohol or abstinence of safety gear such as helmet. Alcohol dampens the reflexes needed to effectively control the motor vehicles in this dangerous situation. Mitra et al. have noted that drunkards have a higher odds ratio of injury as compared to nondrinkers.[9]

Since our hospital located in the city outskirts, we included patients from nearby rural places also. It is not surprising to find victims from remote locations. Poor illumination of roads and construction of the non-concrete red soiled roads that are slippery are mainly responsible for RTA in rural areas. Dogs top the AVC chart in our study. Canal et al. in their study in Spain have also found that dogs are involved in more than 80% of AVC.[11] The dogs suddenly enter the roads and disturb the driver's attention and cause accidents. In cases of two-wheelers, the riders fall and get injured as per the speed of the vehicle as they attempt to avoid colliding with the animals or sometimes the vehicle imbalances as it runs over the animal. The animal is rarely harmed in such a situation, unlike the motorized four-wheelers and heavy vehicles that can be fatal for the canine. In contrast, the cows and oxen tend to bottleneck and block the roads. During darkness (night-time or poor illumination of roads), the driver cannot spot the larger mammals and can bump into them. A fatal accident was reported, in a nearby town of our state when a high speeding bus collided with an ox and fell off the bridge in the late night, causing heavy casualty.[12] In our series, we find the AVC to be highest in the evening time. Canal et al. have also reported higher accidents during twilight.[11] This is attributed to a combination of the peak traffic time, slowing of reflexes (driver's fatigue) and the higher number of animals on the road during this period. Furthermore, during this period, there is an increased activity pattern of animals, poor visibility conditions, and glares from animals, all of which contribute to the daily time distribution of RTA. Jiya Ying et al. in a study conducted in Australia found kangaroos to be involved in AVC in more than 50% of cases and dogs contributed to another 11%.[13] While the authors found head injury to be the leading cause of hospitalization in their series, we had external injuries to be the most common presentation. The higher number of speedy motor vehicle involved in their series as compared to two-wheelers in our study might be responsible for these differences.[13] Wilkins et al. found deer to be the most common reported animals in AVC and they also stated that more than 70% occurred in dark or unlit locations.[2] Interestingly, the authors further report that even though motorcycles account for <5% of total AVC, they are the one that is more fatal as the drivers are unprotected.[2]

Among the monthly statistics, we find a relatively less number of RTAs in the colder months, as animals tend to rest themselves in warm and cozy places. EL Faouzi et al. have an exciting note for weather conditions, particularly the rainfall and fog that contribute to AVC. Apart from reduced visibility in these situations, a greater braking distance is required to avoid accidents.[14]

The problem of the rising number of stray animals on roads is also animal specific. There is a rise in the number of stray canines because of uncontrolled population growth. Whereas, the cows and other cattle are seen as either they have been disowned or the owners of the livestock also let them off, mostly during the daytime to graze outside and save costs on cattle feed. The municipal corporation has certain rules and guidelines to control both the situations though its implementation is suboptimal, leading to the alarming rise of RTA due to animal menace. The central government, 2001, has delegated the municipal corporation and the local authority the power to sterilize street dogs as per Animal Birth Control Programme for Dogs rules.[4] In our country, capturing and culling of the stray dogs are banned as per “the Prevention of Cruelty to Animals Act, 1960;” hence, neutering the dogs is the only solution to control the population.[15] Canal et al. have found that dog-associated AVCs show a “cluster pattern.”[11] Therefore, they have suggested posting of a warning signboard to increase the awareness among drivers. Similarly, to control the stray cattle, there is a provision of imposing fine to the owners, and there are shelters also for the homeless.[4] However, the number of such homes for stray animals is insufficient and mostly in urban areas. Deforestation for agricultural and urban land uses have grossly reduced the feeding area for the cattle who have resorted to wandering on roads for feeding on the garbage.[16]

There are certain limitations in our study. Our prospective, cross-sectional study of victims of RTA due to stray animals lacks data on the animal casualty and fatalities. We also lack adequate data on RTA due to wild animals such as elephant and deer, which are rare in our setup.

CONCLUSION

Our prospective, cross-sectional study aimed to highlight the alarming facts of increased incidence of RTAs due to stray animals roaming freely on roads, thus adding significant morbidity and costs to society.

Trauma due to AVC is a preventable cause of RTA. It can be minimized by stringent measures from the governmental agencies and other stakeholders, including public awareness to make sustainable action plans to prevent animals on streets and major roads. Strict implementation of motor vehicle act to control overspeeding vehicles, avoidance of alcohol, and use of the helmet will reduce associated injuries.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.