Scabies, a contagious skin infection that spreads rapidly in crowded conditions

Kolkata: Scabies is a contagious skin infection that spreads rapidly in crowded conditions and is found worldwide.The principal sign of the disease is a pimple-like rash that is most commonly found on the hands, especially the webbing between the fingers, the skin folds of the wrist, elbow or knee, the penis, the breast or the shoulder.

Human scabies is a parasitic infestation caused by Sarcoptes scabiei var hominis. The microscopic mite burrows into the skin and lays eggs, eventually triggering a host immune response that leads to intense itching and rash.

Scabies infestation may be complicated by bacterial infection, leading to the development of skin sores that, in turn, may lead to the development of more serious consequences such as septicaemia, heart disease and chronic kidney disease.

In 2017, scabies and other ectoparasites were included as Neglected Tropical Diseases (NTDs), in response to requests from Member States and the recommendations of the WHO Strategic and Technical Advisory Group for NTDs.

Scabies is one of the commonest dermatological conditions, accounting for a substantial proportion of skin disease in developing countries. Globally, it is estimated to affect more than 200 million people at any time, although further efforts are needed to assess this burden. Prevalence estimates in the recent scabies-related literature range from 0.2 to 71 per cent.

Scabies is endemic in many resource-poor tropical settings, with an estimated average prevalence of 5 ? 10 per cent in children. Recurrent infestations are common. The sheer burden of scabies infestation and its complications imposes a major cost on health-care systems.

In high-income economies, cases are sporadic, yet outbreaks in health institutions and vulnerable communities contribute to significant economic cost in national health services.

In 2015, it was estimated that the direct effects of scabies infestation on the skin alone led 0.21 per cent of disability-adjusted life-years (DALYs) from all conditions globally. The indirect health impact of scabies complications, including bacterial infection, renal and cardiovascular disease may be far greater.

Scabies occurs worldwide. However, it is the most vulnerable groups - young children and the elderly in resource-poor communities - who are especially susceptible to scabies and the secondary complications of infestation.

The highest rates of infestation occur in countries with hot, tropical climates, especially in communities where overcrowding and poverty coexist, and where there is limited access to treatment. (UNI)