Scabies, a contagious skin infestation caused by the mite Sarcoptes scabiei var. hominis, remains a substantial public health challenge globally.

Despite being preventable and treatable, scabies affects millions annually, imposing significant burdens on healthcare systems and vulnerable populations.

Epidemiology and Global Burden

Globally, scabies is estimated to affect over 130 million people at any given time, translating to hundreds of millions of new cases annually. The disease disproportionately impacts children, older, institutionalized individuals, and marginalized communities, particularly in tropical regions and low-resource settings.

Its prevalence varies widely; endemic regions report infection rates exceeding 20% of the population, while sporadic outbreaks occur in high-income countries within crowded environments like nursing homes, prisons, and schools.

Transmission and Risk Factors

Scabies spreads primarily through prolonged skin-to-skin contact, facilitating rapid transmission within families, communities, and institutional populations. While poor hygiene is not a direct cause, overcrowding and limited access to healthcare amplify transmission risk. The mite burrows into the upper layers of skin, where it lays eggs, causing intense itching and skin inflammation.

Risk factors heighten vulnerability in certain groups, including immunocompromised individuals, people living in refugee camps, and those in close quarters such as boarding schools. The highest rates are reported among children in endemic areas, reflecting both environmental and social determinants.

Health Implications and Complications

Beyond the hallmark symptom of severe itching, scabies significantly impacts quality of life through sleep disruption, social stigma, and impaired daily functioning. The persistent scratching damages the skin barrier, predisposing individuals to secondary bacterial infections such as impetigo.

These infections can escalate to serious systemic complications including sepsis, post-streptococcal glomerulonephritis, and rheumatic heart disease, contributing substantially to morbidity and mortality in affected populations.

Health economists estimate that scabies imposes a substantial economic burden due to healthcare costs and loss of productivity. A study highlights scabies as a cause of millions of years lived with disability worldwide, emphasizing the need for concerted control efforts.

Control Efforts and Treatment Strategies

Effective management of scabies requires prompt diagnosis, treatment of affected individuals, and simultaneous treatment of close contacts to prevent reinfestation. Standard therapies include topical scabicides such as permethrin cream, as well as ivermectin, particularly in outbreaks or cases refractory to topical treatments.

Mass drug administration (MDA) programs delivering ivermectin to entire communities in endemic areas have demonstrated success in reducing prevalence and transmission. The classification of scabies as a neglected tropical disease highlights a global commitment to expanding control efforts.

Comprehensive approaches also address environmental decontamination and health education to break transmission cycles. Challenges persist in ensuring access to treatments, adherence to protocols, and overcoming social stigma, particularly in resource-limited settings.

Dr. Fuller warned, "Eight years after scabies was officially recognized as a neglected tropical disease, it continues to pose a global public health challenge, particularly among children, institutionalized individuals, and migrant populations."

The Road Ahead

Sustainable control of scabies hinges on integrated public health initiatives combining improved surveillance, expanded access to effective treatments, and community engagement. Advancements in diagnostic techniques and treatment options promise greater efficacy, while global partnerships and funding will accelerate progress.

Addressing scabies within broader health and social frameworks recognizes its role as both a medical and socio-environmental problem. Success in reducing its burden will improve health equity, reduce healthcare costs, and alleviate suffering in some of the world's most marginalized communities.

Scabies remains a persistent and evolving public health challenge with widespread prevalence across diverse settings. Its transmission fueled by close contact and overcrowding leads to significant physical, social, and economic consequences. Enhanced awareness, timely treatment, and coordinated control programs are essential to reducing the global scabies burden.