Analysis of 10 cases of monkeypox in Changning District， Shanghai / 上海预防医学

ABSTRACT

ObjectiveTo analyze the clinical and epidemiological characteristics of confirmed cases of human monkeypox infection in Changning District， Shanghai， and to explore their clinical and epidemiological characteristics. MethodsClinical data from 10 reported cases of monkeypox in individuals residing in Changning District or identified by local medical institutions between July 20 and September 30， 2023， were collected. Epidemiological case investigations were conducted， and throat swabs， anal swabs， and rash swabs were collected by the treating medical institutions. Real-time fluorescence quantitative PCR was used for monkeypox virus nucleic acid testing， and descriptive epidemiological analysis was applied to analyze the epidemiological characteristics of the cases. ResultsAll 10 confirmed cases of human monkeypox infection were all young males with an average age of 35.4 years， all of whom belonged to the men who have sex with men （MSM） population， with no occupational clustering. The primary clinical symptoms included fever， rash， enlarged inguinal lymph nodes， and muscle soreness. Nine cases presented with a rash， and seven cases experienced fever symptoms. Among the 10 cases， one experienced fever， rash， enlarged lymph nodes， and muscle soreness； two had fever， rash， and enlarged lymph nodes； two had fever， rash， and systemic soreness； two had only a rash； one had fever or rash； and one was asymptomatic. Among the nine cases with a rash， the rash was mainly localized to the genital or anal area， with fewer cases presenting rashes on the limbs or trunk simultaneously. All cases reported a history of non-exclusive MSM behavior within 21 days before the onset of the disease. The interval between the last suspected high-risk exposure and the onset of symptoms was 4 to 10 days， with an average interval of 6.9 days. The time from the onset of fever to the appearance of a rash was 0 to 5 days， with an average of 1.87 days. ConclusionThe main clinical manifestations of human infection with monkeypox are fever， rash， and enlarged inguinal lymph nodes. The MSM population is a high-risk group for monkeypox infection， and its source of infection may be associated with MSM exposure. Early-stage symptoms are mild， leading to potential underdiagnosis. Additionally， patients may conceal information during the investigation process， which increases the difficulty of epidemic prevention and control.