这种疾病主要累及儿童,在热带气候区域 2-11 岁儿童中发病率接近 20%。[3]Sturt RJ, Muller HK, Francis GD. Molluscum contagiosum in villages of the West Sepik District of New Guinea. Med J Aust. 1971;2:751-754.http://www.ncbi.nlm.nih.gov/pubmed/5117269?tool=bestpractice.com成人通过性传播也可被感染。软疣的发病率没有性别或种族倾向。[4]Becker TM, Blount JH, Douglas J, et al. Trends in molluscum contagiosum in the United States, 1966-1983. Sex Transm Dis. 1986;13:88-92.http://www.ncbi.nlm.nih.gov/pubmed/3715678?tool=bestpractice.com从 1994 年到 2003 年在英国和威尔士进行的一项研究发现,到家庭医生处就诊的男性发病率为 243/10 万人年,女性是 231/10 万人年;90% 病例见于 15 岁以下儿童。[5]Pannell RS, Fleming DM, Cross KW. The incidence of molluscum contagiosum, scabies and lichen planus. Epidemiol Infect. 2005;133:985-991.http://www.ncbi.nlm.nih.gov/pubmed/16274495?tool=bestpractice.com在美国,20 年以来发病率升高,但缺乏最近的流行病学数据。而且儿科发病率趋势还没有被监测。世界范围内,热带气候发病率更高。[3]Sturt RJ, Muller HK, Francis GD. Molluscum contagiosum in villages of the West Sepik District of New Guinea. Med J Aust. 1971;2:751-754.http://www.ncbi.nlm.nih.gov/pubmed/5117269?tool=bestpractice.com由于软疣可通过性接触传播,垂直传播也有报道。[2]Luke JD, Silverberg NB. Vertically transmitted molluscum contagiosum infection. Pediatrics. 2010;125(2):e423-e425.http://www.ncbi.nlm.nih.gov/pubmed/20064865?tool=bestpractice.com