Nearly half of the patients required hospitalization. Presentation included rash, fever, respiratory symptoms, and lymphadenitis, which all occurred in most of the patients. None of the U.S. cases were fatal, but there is a mortality rate of up to 10% associated with the infection in Africa.
Monkeypox can be differentiated from chickenpox by the fact that lesions in monkeypox are at the same stage at the same time, while chickenpox lesions can be seen in various stages at the same time as early as the second day of disease.
The smallpox vaccine can prevent monkeypox, and should be given to those with occupational exposures, and to close contacts of infected individuals.
The moral of the story: Get a real dog, not a prairie dog, Dr. Feigin quipped.
▸ Varicella vaccination. Two doses of varicella vaccine are better than one, according to the results of this study.
In 2,200 children randomized to receive either one or two doses of vaccine and followed for 10 years, the rate of varicella infection and persistence of varicella antibodies were compared. A total of 71 cases (including 15 confirmed cases) of varicella were reported in the one-dose group, compared with 25 cases (including 4 confirmed cases) in the two-dose group. The differences were statistically significant.
The vaccine efficacy rate was 94% for one dose, and 98% for two doses (Pediatr. Infect. Dis. J. 2004;23:132-7).
The authors concluded that both one and two doses result in long-term protection against varicella, but that the two-dose regimen is more effective. Dr. Feigin noted that in those over age 12 years, two doses are currently recommended, because after one dose the seroconversion rate is 78%-82%, and after two doses it is 99%.
