Narayan Consultancy on Veterinary Public Health and Microbiology, Bharuch, Gujarat, India
Animal and human bonding is very old as human is dependent on animals for food, transport, and recreation etc. [1]. The close asso- ciation of humans with animals gave an opportunity for the microbes to transmit from animals to humans and vice versa. Such infections are called zoonoses, and presently, more than 300 zoonotic diseases with multiple etiologies are reported from many regions of the world [2]. There are many infections that humans can acquire from a wide variety of animals. Very rarely, man can also transmit the infection to animal. Such infections are termed as reverse zoonoses or zooanthroponoses [1]. The transmission of infection from animal to people can occur by several routes, such as ingestion, direct contact, inhalation, animal bites, blood transfusion, and bite from arthropod vectors [3]. The pathogen is easily transferred in the susceptible individual by the bite of an infected animal. There are several zoonotic diseases, such as rabies, cat scratch fever, rat bite fever, monkey pox, herpes simiae, pasteurellosis, sporotrichosis, blastomycosis, and parrot fever, tularemia, which are transmitted by the bite of animals [1,4-7].
Bites from various types of animals, such as cat, dog, monkey, rat, mice, rabbit, fox, wolf, horse, bat, mongoose, bird, and snake etc, pose a public health problem both in developing as well as developed nations of the world [1,8]. Most cases of animal bites are inflicted by pet animals that include dogs, and cats [9]. Globally, dog bites are responsible for tens of millions of injuries annually [8]. It is estimated that approximately 5 million people in the world, mainly from Africa and South-East Asia are bitten by snake each year [8]. There are about 4.5 million cases of dog bites in USA annually [8]. Pasteurella multocida infection in dog bite wound has been reported from many countries of the world including India [1,8-10]. A study conducted by Yalchin and co-investigators [9] from Turkey revealed that most cases of bite were due to dogs (68.04%), followed by cats (28.45%), mice (2.56%), and other animals (0.95%). Maximum cases were observed in patients below the age of 18 years, and the bites mostly occurred on the upper extremities (53.83%), as compared to lower extremities (38.03%). There are 30 species of Pasteurella of which Pasteurella multocida is of medical importance [11]. The organism occurs as a commensal in the upper respiratory tract of several species of animals including cats and dogs [1]. It is a small ovoid, rod-shaped, nonmotile, non-spore- forming, capsulated, aerobic, gram-negative bacterium which failed to grow on MacConkey’s medium. Pasteurella multocida is positive for oxidase, catalase, and indole; and also has the ability to ferment glucose, sucrose, mannitol, and sucrose [10]. The bacterium is found sensi- tive to several antibiotics like erythromycin, penicillin, tetracycline, and cephalosporins [12].
Natural infection due to Pasteurella multocida infection has been encountered in humans and in also in bison, buffalo, cat, camel, cattle, dog, goat, horse, pig, poultry, rabbit, sheep, wild animal, and yak [1]. The children are at highest risk of getting animal bites as compared to adults. The bacterium can infect the humans following the bite or scratch of pet animals, and therefore, bite of pet animals is recognized as the principal mode of transmission of P. multocida infection in humans [1,9,10]. Most infections in humans show local cellulitis and inflammation of bite area. Occasionally, other symptoms, such as respiratory disorder, sinusitis, bronchitis, alveolitis, tonsillitis, otitis, septicemia, peritonitis, pyelonephritis, endocarditis, and meningitis have been noticed [1,10]. The patients with endocarditis, meningitis, and septicaemia may have mortality rate from 25 to 30% [13]. Microscopic examination of the pus smear shows small, ovoid, and coccobacilli shaped gram-negative organisms [10]. The isolation of pathogen from wound swab, purulent exudate, sputum, nasal swab, blood, sputum, bronchial washing, synovial fluid, and cerebrospinal fluid (CSF) should be attempted on blood agar [1]. The bacterial growth on sheep blood agar reveals smooth, round, grayish and non-hemolytic colonies after 24 hours of incubation [14]. The bacterium does not grow on MacConkey’s agar [14]. Several biochemical tests are employed to confirm the isolate as P. multocida [10]. Molecular tools are also employed for the detection and characterization of P. multocida [15]. The bacterium should be differentiated from Staphylococcus aureus, Clostridium tetani, and Bartonella henselae [16].
Currently, no vaccine is available to immunize the humans against P. multocida infection. Meticulous cleaning of wound with sterile saline, immediate antibiotic therapy, and administration of tetanus vaccine if the patient has not taken earlier is imperative [1,8,14]. If the infec- tion is deep seated, it is advised to have surgical drainage. Several antibacterial antibiotics, such as penicillin, tetracycline chloramphenicol, oxytetracycline, and cephalosporins are used for treating the cases of Pasteurella infection [1]. Sometimes, from pet animal bites can be life threatening, especially among the immunocompromised patients if the proper treatment is delayed. Therefore, prompt medical interven- tion is essential to save the life of victims. Vaccines are available for immunization of animals [1,14]. Proper handling of cat and dog to avoid bites, and immediate attention of animal bite wounds are imperative for the prevention of P. mul- tocida infection [1]. It is suggested that antibiotic therapy should be started after the drug sensitivity report. The patient having chronic respiratory disorder with history of bite with pet animals must be prudently investigated for P. multocida infection. Emphasis is given that all animal bite cases must seek prompt medical intervention in order to avoid the complications. Attempts to develop safe, potent, and low-cost vaccine for immunization of high-risk groups will be rewarding. One health approach that involves the specialists from different organizations, such as medical, veterinary, wildlife etc. appears obligatory for the control of zoonotic infections including pasteurellosis.
Mahendra Pal. “Can Pasteurella multocida be Transmitted by the Bite of Pet Animals?”. EC Microbiology 21.4 (2025): 01-03.
© 2025 Mahendra Pal. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Open Access by ECronicon is
licensed under a Creative Commons Attribution
4.0 International License
Based on a work at www.ecronicon.net
