**8. Rabies in camelids**

#### **8.1 Epidemiology**

Camelids are susceptible to rabies. However, most of the publications described clinical rabies in dromedary camels (*Camelus dromedarius*), with few reports in Bactrian camels (*Camelus bactrianus*) [8, 46] and the New World camelids [67]. From 2006 to 2013 in Oman, foxes reported the highest positivity rate (70.1%), camels accounted for the second higher positivity (59.7%) for rabies diagnosis [63]. Camels were the second most likely livestock after cattle to test positive for rabies in Mongolia from 1970 to 2005 [45]. Camels were the fourth (4.2%) mainly rabies tested positive animals during 2004–2018 in China [46]. In China, rabies infection in camels was reported [8]. According to the confirmed rabies cases in Saudi Arabia during 2010–2017 [15], Dogs and dromedary camels were the most affected species. In Iran, a review on zoonotic diseases published articles [11] revealed that camels are one of the essential sources as well as carriers of infection for humans, livestock, and wildlife in Iran and worldwide. Rabies is highly endemic in Iran; it is circulated easily in wildlife and livestock. The authors reviewed reported camel rabies cases in Iran, 3 cases during 1996–2006; an outbreak of camel rabies was reported for the first time in 2008 in central Iran. A rabid wolf attacked 8 camels; another camel rabies in the east was reported in 2012 [11]. In Jordan, Rabies in 8 camels was described [12]. In India, a report of clinical signs of rabies in she-camel was described [4].

Reports of rabies in dromedary camels from Morocco, Mauritania, Sudan, Yemen, Saudi Arabia, UAE, Niger, Jordan, India, Israel, and Iran were reviewed by Abbas and Omer [19]. Ali et al. (2004) reviewed dromedary camel rabies in Sudan; the first confirmed rabies cases were in 1926, then laboratory-confirmed cases continued to be reported, 17 cases from 1927 to 1939, 21 from 1940 to 1970. Other cases were reported in different parts of the country, 21 in the north and 16 in the Western States. Camel population in Sudan is about 4.8 million; the reported rabies cases are very few compared to the population, which is mainly due to under-reporting. Other cases in camels were reported as well in Sudan [20].

In a review about camel diseases, many rabies cases have been reported in Mauritania, Saudi Arabia, Iran, and Pakistan; infection is usually due to rabid dog bites [68]. In Niger, an outbreak of rabies in the camel herd due to feral dog bites was reported [69].

Rabies outbreak in camels in Iran was described [70]. An outbreak of dog rabies in the camel herd was reported in Sudan in 1998, and it resulted in the death of 19 camels [71]. Antibodies against rabies were detected in non-vaccinated camels imported for slaughtering in Nigeria, which may indicate subclinical rabies infection [72]. Very few suspected rabies cases in camels were reported in Morocco during 1991–2015 [27].

#### **8.2 Clinical signs**

Camels with furious rabies form show restlessness, anxiety, salivation, and attacking and biting form followed by terminal paralysis, lateral recumbency (**Figure 6**) and a characteristic flexion of four limbs, reviewed by Abbas and Omer [19]. Mohammadpour et al. (2020) reviewed a report stating that a furious form of rabies is seen in most of cases in camels.

Rabies clinical signs observed in Bactrian camels were reduced appetite, excessive activity and agitation, cessation of rumination, lip twitching, hypersalivation, tachypnea and howling, paralysis [8]. Some reports described the occurrence of

**Figure 6.** *A case of rabies in a dromedary camel showing lateral recumbency and excessive salivation.*

rabies dumb form more frequently. Most rabies cases (67%) in camels in Oman were of the dumb form; observed clinical signs were restlessness, salivation, head and neck rotation in all directions, paralysis, recumbency, and death [73]. Clinical signs seen in rabid camels were hyperesthesia, profuse salivation, anorexia, and paralysis [12]. In India, clinical signs of rabies in the camel described the appearance of hyperexcitability, bellowing, aimless running, salivation, convulsions, swaying of the hindquarters and recumbency, biting tendency to the owner and wooden objects [4]. Noticed rabies clinical signs in camels were unusual behavior including aggression, pica, ptyalism, and terminal paralysis [69]. During an outbreak of rabies in camels, reported clinical signs were high sensitivity, ferocity, biting faces of other camels, bloat, restlessness, limb paralysis, and yawning [70]. In a rabies outbreak, clinical signs noticed in most of the affected camels were restlessness, irritability with very harsh and loud sounds. Later excitement became noticeable. There were then rubbing incoordination (staggering gait), tenesmus, abnormal sexual behavior: (she-camels mounting each other), raising of tails, and slight salivation, terminated by paralysis of the hindquarter, recumbency, and death of 19 camels [71]. In Khartoum, two camel rabies cases in 1996, 1997 showed off food, salivation, nervous signs followed by biting fence and their forelimbs and abdomen, then recumbency, hind limbs paralysis, and death [74]. An almost similar picture was previously reported by Afzal et al. [75], which were hyper-excitability, salivation, attacking inanimate objects, biting of its forelimbs, sternal recumbency, paralysis of hind legs, and death.

### **8.3 Transmission**

Transmission of rabies to camels is mainly through dog bites, except in some countries where wild animals like foxes and wolves are involved. In China, the main rabies transmitters are dogs; meanwhile, in border areas, the wild fox is [46]; camels were reported to be rabies-infected by dogs and wild foxes [8]. In Iran, a rabid wolf was reported to transmit the infection to camels [11]. In Oman, the main animals involved in rabies transmission are foxes [63]. In another study in Oman, it was noticed that most rabid camels were bitten by foxes, which confirmed the major role of foxes in rabies transmission [13]. In Saudi Arabia, the majority (70%) of camel rabies cases were due to wild dog bite, while wild foxes accounted for about 17% of cases [73]. Almost in all reported camel rabies cases in Sudan, dogs were the source of infection [18, 62, 71, 74]. The same finding was reported in other African as well as Asian countries, Niger [69], Mauritania, Saudi Arabia, Iran, and Pakistan [68], China [8] Saudi Arabia [15].
