Molluscum Contagiosum: Global Distribution and Regional Incidence Patterns

The incidence and prevalence of molluscum contagiosum (MC) varies significantly across different countries and regions worldwide, with several key geographic and climatic patterns emerging from available epidemiological data.

Countries and Regions with High Incidence Rates

Papua New Guinea and Pacific Islands

Papua New Guinea demonstrates some of the highest documented prevalence rates of molluscum contagiosum globally. Studies from the West Sepik district of New Guinea reported a prevalence rate of 22% in children under 10 years, with an overall population prevalence of 7%^[1]^[2]. The annual incidence rate for children under 10 years of age was documented at 6%^[1]. In rural villages, the age distribution showed that 93% of cases occur in children under age 10, with an age range from 3 months to 57 years^[3].

East Africa

East Africa shows particularly high prevalence rates, especially among young children. Studies have documented 52% prevalence in children aged 2 years in East African populations^[4]. This represents one of the highest regional prevalence rates documented globally.

West Africa

Mali, representing West Africa, shows a notable incidence of molluscum contagiosum with 3.6% of children affected, making it among the most frequent dermatoses in children in this region^[5]^[4].

Australia and Developed Countries

Australia shows substantial prevalence with an overall seropositivity rate of 23% in population studies^[4]^[6]. Studies indicate a point prevalence ranging from 5.1% to 11.5% in children aged 0-16 years^[7]^[1].

Regional and Climatic Patterns

Warm and Tropical Climates

Molluscum contagiosum demonstrates a clear association with warm, humid climates. The infection is more prevalent in warm climates than cool ones^[8] and shows higher rates of occurrence in geographical areas with warm climates^[9]. Multiple sources confirm that transmission is more common in warm, tropical, humid environments^[10]^[11]^[12].

The incidence increases almost threefold in countries with warm or tropical climates^[13], with the virus thriving in warm, humid places^[14]. This pattern is consistently observed across different studies, with higher prevalence rates documented in warmer climates^[1].

Developing vs. Developed Countries

There's a notable difference in age distribution between developing and developed countries. The peak onset of molluscum contagiosum in developed countries ranges from age 6 to 12 years, while children in developing countries show different patterns^[15]. In developing countries, the condition occurs at younger ages (2-5 years) compared to developed countries (5-12 years)^[16].

Specific Country Data

United States

The U.S. shows considerable burden with an overall prevalence of approximately 5% in the general population^[17]. Among American Indian and Alaska Native children, the incidence rate was 15.34 per 10,000, with children aged 1-4 years showing the highest incidence at 77.12 per 10,000^[18]. The western regions of the U.S. demonstrated higher incidence rates^[19]^[18].

European Countries

Germany shows a 14.8% seroprevalence in children and adults aged 0 to 40 years^[6]. The UK demonstrates 30.3% seroprevalence in a group of healthy individuals^[6]. However, European countries generally show lower prevalence compared to tropical regions.

Asia

Japan shows relatively lower seroprevalence at 6% of the healthy population^[6]. Studies from Indonesia report worldwide incidence estimates of 2-8%, with higher rates of 5-18% in HIV/AIDS populations^[20].

Environmental and Social Factors

Overcrowded Conditions

Molluscum contagiosum is endemic in densely populated communities, poor hygiene, and poor areas^[4]. It's more prevalent in overcrowded environments^[8] and shows higher incidence in institutional settings. Studies from orphanages in India documented 24.32% of children affected^[21].

Swimming Pools and Water Activities

There's a consistent association between swimming activities and molluscum contagiosum transmission. The condition has been linked to swimming pool usage^[1] and transmission appears to be more likely in wet conditions, such as when children bathe or swim together^[8].

Summary of Highest Incidence Regions

Based on available data, the regions with the highest documented incidence rates of molluscum contagiosum include:

Papua New Guinea and Pacific Islands - up to 22% prevalence in children
East Africa - up to 52% prevalence in young children
Tropical and subtropical regions globally - consistently higher rates
Warm, humid climate regions - 3-fold higher incidence
Areas with poor sanitation and overcrowding - elevated transmission rates

The data consistently shows that warm, humid climates combined with factors such as overcrowding, poor hygiene, and frequent water contact create optimal conditions for molluscum contagiosum transmission, resulting in significantly higher incidence rates in these geographic regions compared to temperate climates and developed countries with better sanitation infrastructure.

31st Jul 2025

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