How Human Acne Compares to Other Mammals
Acne vulgaris is a disease caused in humans by the skin’s inflammation response to different bacteria such as Propionibacterium acnes and Corynebacterium acnes. P. acnes normally reside on the skin without any problems, but it becomes a problem when these bacteria get into clogged pores like sebaceous glands and hair follicles1. A direct correlation exists between how much sebum is produced by the sebaceous glands and how much acne a person gets. Androgenic hormone production also correlates to more acne in humans and is why it is so common in teenagers. It has been shown that P. acnes produces certain fatty acids that increase the skin’s inflammation response, contributing to acne.
Animals other than humans can also get acne, as other animals also produce sebum and carry P. acnes on their skin. Acne has been found in many animals that grow hair, but often occurs when these animals have been shaved. Monkeys, dogs, cats, and mice have all shown limited forms of acne. Dogs have been shown to have acne similar to humans in that they normally get acne during puberty, but this is much less severe in dogs because their adolescent period is shorter than humans. Cats get acne, but it is not majorly involved in adolescence like it is in dogs and cats. Cats have been shown to mainly get acne based on sanitation. Cats clean themselves by licking and are known to mainly get acne in areas that they cannot easily clean like their chins2. P. acnes taken from humans has been shown to cause acne in mice when injected onto their backs. The extent of how much acne is caused in mice differs greatly from one mouse strain to another and has been shown to be the greatest in hairless mice3.
One of the reasons it is believed that humans get more acne than other animals is that humans have evolved from animals who had a lot of hair to not having much hair. This means that human bodies still produce a lot of sebum as though they have more hair than they do, and they don’t have enough hair to absorb this sebum which gives them more opportunities to get acne. Non-human animals are caused much less distress by their acne as they do not have the capability to judge each other’s appearance like humans do.
Why You Get Acne, But Your Pets Don’t. 2018. IFLScience. http://www.iflscience.com/health-and-medicine/why-you-get-acne-but-your-pets-dont/. Accessed June 24, 2018
Frederick Miller, “Spontaneous Animal Models of Human Disease. Volume 1 and Volume 2. Edwin J. Andrews , Billy C. Ward , Norman H. Altman ,” The Quarterly Review of Biology 55, no. 3 (Sep., 1980): 29-30.
Jang YH, Lee KC, Lee S-J, Kim DW, Lee WJ. HR-1 Mice: A New Inflammatory Acne Mouse Model. Annals of Dermatology. 2015;27(3):257-264. doi:10.5021/ad.2015.27.3.257.