ABSTRACT
We present a literature review of dermatology features in historical pandemics. A pandemic is an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and affecting a large number of people. Smallpox was the first documented pandemic, around 10 000 BC, spread by the inhalation of airborne droplets. A few days after an initial high fever, headache and fatigue, a mucocutaneous maculopapular eruption appeared, which then developed pustules and erosions. The last outbreak occurred in the USA in 1949. Smallpox was eradicated in 1980, following a vaccination programme. Mycobacterium tuberculosis is the causative agent of tuberculosis (TB), an ongoing global pandemic. The earliest documentations were 3300 years ago. In 2020, the World Health Organization (WHO) provisionally estimated 1.5 million deaths globally. Most commonly affecting the lungs, cutaneous TB may present with inflammatory papules, plaques, suppurative nodules and chronic ulcers. Requiring long, complex antibiotic regimens, multidrug resistant TB is an increasing problem. Now extremely rare, yet still with recent outbreaks in 2021 in Madagascar, bubonic plague arrived in Europe in 1346 causing 75-200 million deaths. It is caused by the bacterium Yersinia pestis, transmitted through fleas that have fed on infected rodents. Clinical features include papules, pustules, ulcers and eschars, tender lymphadenopathy and systemic symptoms, and it responds to antibiotics. Syphilis, caused by the bacterium Treponema pallidum, is sexually transmitted. The first known outbreak was during warfare in 1494-5 in Naples, Italy. In 2020, the WHO estimated that, globally, seven million people had new infections. Primary syphilis typically produces a painless, genital ulcer (or chancre). Secondary syphilis presents with a nonitchy, maculopapular erythema over the trunk, palms and soles. Early recognition and antibiotic treatment usually lead to good outcomes. Estimated by the WHO to affect 37.7 million people in 2020, HIV is thought to have mutated from simian immunodeficiency virus by the 1960s in sub-Saharan Africa, spreading to the Caribbean and USA by the late 1960s. Initial symptoms include a fever, headache and lymphadenopathy. Dermatological features are common, including opportunistic cutaneous infections, nonspecific exanthemas, seborrhoeic dermatitis and Kaposi sarcoma. Advances in antiretroviral therapies mean people with HIV can have an excellent prognosis, although the WHO estimated in 2020 that more than 200 000 people with HIV died from concomitant TB. Since 2019, COVID-19 has had a considerable global impact on healthcare. With more than 300 million cases and 5.5 million deaths to date, some services have been overwhelmed owing to large case numbers, variable vaccine uptake, workplace changes to reduce transmission and staff shortages. Cutaneous features include perniosis, urticarial, purpuric, vesicular or maculopapular eruptions. Pandemics throughout history have been repeatedly shown to present with an element of skin involvement. We can utilize this to promote education and early recognition of these features, to facilitate diagnosis and raise awareness of the potential complications of serious diseases.