Most people infected with the worms that cause lymphatic filariasis never develop symptoms;<ref name=CDC>{{cite web|url=https://www.cdc.gov/filarial-worms/about/lymphatic-filariasis.html?CDC_AAref_Val=https://www.cdc.gov/parasites/lymphaticfilariasis/index.html |accessdate= though some have damage to [[lymph vessel]]s that can be detected by [[medical ultrasound]].{{sfn|Despommier|Griffin|Gwadz|Hotez|2019|p=258}} Months to years after the initial infection, the worms die, triggering an immune response that manifests with repeated episodes of [[fever]] and painful swelling over the nearest [[lymph node]]s (typically [[Inguinal lymph nodes|those along the groin]]).<ref name=CDC/>{{sfn|Despommier|Griffin|Gwadz|Hotez|2019|p=258}} In areas with [[endemic]] lymphatic filariasis, people are typically infected in childhood, and symptoms begin in adolescence.{{sfn|Despommier|Griffin|Gwadz|Hotez|2019|p=258}} After these fevers, some infected people