• Early resuscitation, stabilisation, and transportation of victims to tertiary care, vital

Since wild boars are capable of inflicting fatal injuries to humans, the early resuscitation, stabilisation, and transportation of the victims to appropriate tertiary care are vital, as almost all incidents occur inside forests, jungles, or rural and remote areas which are far from definitive care.

These observations and recommendations were made in case reports on “Wild boar (Sus scrofa cristatus) attacks in Sri Lanka: A case series and review of the literature” which were authored by S. Thalgaspitiya and M. Madusanka (attached to the Rajarata University’s Medicine and Allied Sciences’ Faculty), and B. Wijerathne (attached to Australia’s Dubbo Medical and Allied Health Group) and published in the Anuradhapura Medical Journal’s 17th Volume’s Third Issue in December of last year.

The wild boar (Sus scrofa) is, as mentioned in O. Keuling and K. Leus’s “Sus scrofa. The International Union for the Conservation of Nature Red List of the Threatened”, a mammal found in Europe, North Africa, the Middle East, and Asia. The subspecies, Sus scrofa cristatus (Wagner, 1839) is, as C. Santiapillai and M.R. Chambers’s “Aspects of the population dynamics of the wild pig (Sus scrofa linnaeus, 1758) in the Ruhuna National Park” and W.W.A. Phillips’s “Manual of the mammals of Sri Lanka” mention, distributed from the highest hills to the coasts of Sri Lanka. Adult wild boars measure 155-170 centimetres (cm) in length, 83 cm in height at the shoulder, and weigh between 100 and 127 kilograms (kg), and both male and female wild boars possess long, sharp tusks capable of inflicting severe wounds.

Attacks by wild boars on humans are more frequent in rural and forested areas, as observed in J.G.H. Gubler’s “Septic arthritis of the knee induced by Pasteurella multocida and Bacteroides fragilis following an attack by a wild boar” and an Iranian study. Wild boars can cause a wide range of injuries in humans, including, per S. Manipady, R.G. Menezes, and B.K. Bastia’s “Death by attack from a wild boar”, M. Shetty, R.G. Menezes, T. Kanchan, B.S.K. Shetty, and A. Chauhan’s “Fatal cranio-cerebral injury from wild boar attack”, N.K. Tumram, S.G. Dhawne, V.N. Ambade, and P.G. Dixit’s “Fatal tusk injuries from a wild boar attack” and an Indian study, lacerations, wounds penetrating to the internal organs, fractures, tendon damage, knee joint infections, and, in some instances, death. 

Thalgaspitiya et al. discussed three patients brought and presented to the Anuradhapura Teaching Hospital due to boar attacks. 

The first case  

A 55-year-old farmer was attacked in April 2016, in the inter-monsoon season while he was gathering firewood in the forest in the late morning hours. The previously injured wild boar caused injuries to the front of his left thigh before the farmer could retreat. After the attack, the farmer walked home, and the relatives took him to the hospital within two hours. On admission, he was hemodynamically (relating to or functioning in the mechanics of blood circulation) stable. A large laceration was noted in the front of his left thigh, but the distal neurovascular bundle was intact. The patient was given the intramuscular tetanus toxoid, an intravenous antibiotic and another antibiotic, non-steroidal anti-inflammatory drugs (NSAIDs), and proton pump inhibitors (PPIs). He was vaccinated against rabies, both actively and passively, with the anti-rabies vaccine (ARV) and anti-rabies serum (ARS). Wound irrigation was done under regional anaesthesia in the theatre. There were no bony injuries. The laceration in the quadriceps femoris (the extensor of the knee) muscle was primarily sutured. He was kept in a ward for three days and discharged with oral antibiotics and analgesics for two weeks. On follow-up, no complications were observed, except for the presence of a scar. 

The second case  

In January, 2017, in the North-East monsoon season, a 45-year-old driver sustained injuries to his scrotum while trying to release a trapped wild boar in the early morning hours. He was immediately taken to a peripheral hospital, where the same above-mentioned antibiotics including the one administered IV, yet another antibiotic, the tetanus toxoid, the ARV, the ARS, the NSAIDs and PPIs were given. On admission to the Anuradhapura Teaching Hospital, he was hemodynamically stable. There was a five cm laceration on the right hemi-scrotum, and the right testis was exposed. Wound irrigation and primary suturing were done under spinal anaesthesia. The patient was discharged on the fourth postoperative day, and there were no complications at the two week follow-up. 

The third case 

In January 2017, in the North-East monsoon season, a 53-year-old farmer was attacked by a wild boar while he was chasing parrots in the chena (swidden farming practised in Asian countries) in the early morning hours. On admission to the hospital, he was hemodynamically stable. There were lacerations on the right leg, on the medial aspect of the thigh below the knee, and on the ankle, respectively. There were three lacerations on the left leg. In the operating theatre, no nerve, vascular, muscle, or tendon damage was noted. Wound irrigation and primary suturing were done under local anaesthesia. The patient was given two antibiotics, NSAIDs, and PPIs. The tetanus toxoid, the ARS, and the ARV were given. He was kept in a ward for three days and discharged with the same oral antibiotics and analgesics for a week on the second postoperative day and reviewed after a week. On follow-up, there were no complications. 

Discussion 

Attacks are commonly reported from India where Sus scrofa cristatus is abundant. Most victims are male. Wild boar attacks are more frequent in the winter months, in the morning hours, and during breeding and/or farrowing seasons. The majority of the attacks is unprovoked and occurs while the victims are working on farms, in the vicinity of the jungle, or during a visit to the jungle. In several cases (O. Kose, F. Guler, A.B. Baz, S. Akaln and A. Turan’s “Management of a wild boar wound: A case report”, another Indian study, P.D. Bhingare’s “A case of recto-vesico-cutaneous fistula following perineal injury by wild boar”, I. Okano, Y. Midorikawa, N. Kushima, Y. Watanabe, T. Sugiyama, K. Mitachi, K. Shinohara, T. Sawada, and K. Inagaki’s “Penetrating anorectal injury caused by a wild boar attack: A case report” and H. Nagasawa, K. Omori, I. Takeuchi, K. Fujiwara, H. Uehara, K. Jitsuiki, A. Kondo, H. Ohsaka, K. Ishikawa, and Y. Yanagawa’s “A case of near-fatal drowning caused by an attack from a wild boar”), the wild boar attacked suddenly, from behind, without giving the victims a chance to escape. 

Injuries caused by wild boars range from subcutaneous lacerations to serious injuries involving penetrating injuries to internal organs, bone fractures, tendon damage, knee joint infections, and, in some instances, death. Most of the injuries are from the waist down, including the pelvic region, the thighs, and the legs. Abdominal and chest injuries are reported among the victims who fell during the attacks. In the three above mentioned cases, all of the victims were males, and they were attacked while working in a chena, at the edge of the jungle, or within the jungle. Males visit the forest to gather cattle, gather non-timber forest products (NTFPs), and hunt. Therefore, they are more likely to encounter wild boars. Most of the attacks occurred in the forest, at the fringe of the forest, in orchards, or in farms (per A. Gunduz, S. Turedi, I. Nuhoglu, A. Kalkan and S. Turkmen’s “Wild boar attacks”, H. Attarde, S. Badjate and S.R. Shenoi’s “Wild boar inflicted human injury”, N. Šprem, P. Škavic, D. Deždek and T. Keros’s “The wild boar attack – A case report of a wild boar inflicted injury and treatment” and H. Nagasawa, K. Omori, H. Maeda, I. Takeuchi, S. Kato, T. Iso, K. Jitsuiki, T. Yoshizawa, K. Ishikawa, H. Ohsaka and Y. Yanagawa’s “Bite wounds caused by a wild boar: A case report”). One attack occurred in January and the other in April. One case was an unprovoked attack, but an injured boar was involved in the other two cases. Injured boars are aggressive and more prone to attack. The victims sustained injuries to their thighs, more in the posterior aspect. The average height of a wild boar is around 80-90 cm, which is approximately the height of a human waist. Therefore, a wild boar attack causes more injuries in the perineal area, the thighs, and the legs of the victims. 

The most important step in the initial management of an injury is first-aid to reduce bleeding. The wounds should be thoroughly cleaned and irrigated with normal saline or povidone iodine to minimise the inoculation of bacteria that dwell in wild boars’ mouths. Per M. Barnham’s “Pig bite injuries and infection: Report of seven human cases”, bacteria are commonly found in wounds inflicted by domestic pigs. Thus, prompt treatment with antibiotics must be initiated. All the patients in these cases were treated with broad spectrum antibiotics.

Sus scrofa bites may be deep and may harbour tetanus and rabies, according to I. Brook’s “Management of human and animal bite wounds: An overview” and therefore, tetanus toxoid should be administered depending on the immunisation status of the patient. Injuries to tendons, nerves, vessels, and underlying soft tissues should be explored under appropriate anaesthesia, and any non-viable tissues should be excised to reduce infections. Primary suturing after a mammalian bite is a controversial issue, as some of the sutured mammalian bites are apt to get infected.

Furthermore, hunters, farmers, hikers, and individuals who visit jungles to gather NTFPs are at risk of encountering wild boars and should therefore remain vigilant when venturing into the forests. In the event a wild boar charges at you from a distance where you can safely do so, seek refuge by climbing a tree or by finding an elevated object. If it is not possible to avoid the attack, be prepared to defend yourself.