Considerable debate exists over whether the number of deaths caused by disease in the Haitian Revolution was exaggerated.Although yellow fever is most prevalent in tropical-like climates, the northern United States were not exempted from the fever. The first outbreak in English-speaking North America occurred in New York City in 1668. English colonists in Philadelphia and the French in the Mississippi River Valley recorded major outbreaks in 1669, as well as additional yellow fever epidemics in Philadelphia, Baltimore, and New York City in the 18th and 19th centuries. The disease traveled along steamboat routes from New Orleans, causing some 100,000–150,000 deaths in total. The yellow fever epidemic of 1793 in Philadelphia, which was then the capital of the United States, resulted in the deaths of several thousand people, more than 9% of the population. One of these deaths was James Hutchinson, a physician helping to treat the population of the city. The national government fled the city to Trenton, New Jersey, including President George Washington. The southern city of New Orleans was plagued with major epidemics during the 19th century, most notably in 1833 and 1853. A major epidemic occurred in both New Orleans and Shreveport, Louisiana in 1873. Its residents called the disease "yellow jack".
Pityriasis lichenoides et varioliformis acuta  is a disease of the immune system. It is the more severe version of pityriasis lichenoides chronica. The disease is characterized by rashes and small lesions on the skin. The disease is more common in males and usually occurs in young adulthood, although it has been seen in every age group and every race. It is possible for the disease to go into remission for short periods of time or forever. Causes
There is no known cause of this disease; There is some evidence associating it with Parvovirus B19. Diagnosis
It is commonly misdiagnosed as chickenpox or rosacea, or misidentified as a form of Staph infection. The most accurate way to diagnose it is by biopsy. This disease has not been known to be life-threatening. Treatment
It is not contagious and currently there is no cure for the disease, although the lesions can be treated with phototherapy as well as antibiotics, including erythromycin, azithromycin and tetracycline. Treatment often involves multiple therapies that address the immune system and bacterial, viral, or dermatological causes. Eponym
Pityriasis lichenoides et varioliformis acuta is also known as Mucha–Habermann disease. It is named for Rudolf Habermann (1884–1941), a German dermatologist, and Viktor Mucha, an Austrian dermatologist. See also
Cutaneous T-cell lymphoma
Pityriasis lichenoides
Parapsoriasis
List of cutaneous conditions

References
External links
DermNet scaly/pityriasis-lichenoides