Human pinworm infection may be an underestimated sexually transmitted problem

Human pinworm infections are among the most common intestinal parasitic infections in the world. It is often considered the most common parasitic disease of temperate zones [1]. It is the most common helminthic infection in the United States with approximately 40 million persons infected according to CDC [2]. Last estimates in Poland originate from 2008 when it was still obligatory to report these data and show 5666 persons infected, which seems largely underestimated [3]. In a smaller study from the north eastern region of Poland the prevalence of enterobiasis in a small group of children was 3.33% [4], comparable to the prevalence found in a small group of children in Tucumán province, Argentina [5]. On the other hand, Chinese data show infection rates of 10.2 to even 54.86%, with the average infection rates to be 7.99% in a large group of 17 068 children examined from 2006 to 2010 [6-8]. In fact, enterobiasis seems to be much less common in tropical than temperate climate, e.g. a Nigerian study found the prevalence to be 0.01%, although of note is the fact that stool examination is not the best diagnostic tool for enterobiasis [2, 9]. The infection especially occurs in children with following transmission to all family members, but adults can get infected very easily from other sources, too. The infection may also easily spread in institutionalized persons. The infection is usually acquired by faecal-oral route, from parasite egg-contaminated dirty hands, contaminated objects or contaminated food, but it may also be acquired via sexual contact, specially oral sex with an infected person, including men having sex with men and women having sex with women. The infection is frequently asymptomatic with the most common symptom being perianal pruritus, especially occurring late at night or early in the morning. Sometimes the worms may migrate to the female genital organs and be responsible for inflammatory conditions in and around the vagina [1]. In children it may often present with abdominal pain, irritability and anorexia.