October 15 is Global Handwashing Day, a global advocacy day dedicated to increasing awareness and understanding about the importance of handwashing with soap as an effective and affordable way to prevent diseases and save lives. Parasitology’s Editors have created a collection of freely available papers highlighting the importance of this issue and discussing the wider implications.

With the Sustainable Development Goals, having access to safe water is a global human right. However, like the individuals in the photograph, many peoples of the world today do not have adequate access to potable water. Sadly, they suffer unnecessarily from various communicable and parasitic diseases. This year, we have all seen the importance of effective handwashing in COVID-19 as our frontline tool to stop viral transmission. This is, however, reliant both upon safe water provision and disposal; handwashing protects oneself and the lives of others who may encounter foods, handheld-items, or other surfaces, we may have unintentionally contaminated.

Today we celebrate handwashing. This is often sloganized by ‘good hygiene leads to good health’ and daily handwashing remains a foundation public health intervention. It contributes to the ‘H’ in the WASH (water, sanitation and hygiene) strategies and associated interventions. Nonetheless, each WASH intervention and its components thereof, does not operate in isolation but in combination; for if one critical component fails, then the wider impact of WASH can be lost. Here in the UK, for example, with new gaps in handwashing infrastructures exposed, we have seen the rise of hand sanitiser stations in all types of communal spaces, from shops to hospitals.

Of note is that certain parasitic diseases are directly, or indirectly, associated with handwashing. To exemplify, we have assembled a collection of 9 papers which give specific context. Even more so when we reflect that parasites can be highly adapted for transmission in water – they need to be there! To help set the scene, before the benefits of handwashing were understood, many food-borne parasites were common in the UK as “Intestinal parasites at the Late Bronze Age settlement of Must Farm, in the fens of East Anglia, UK (9th century BCE)” shows. Even today, we have sporadic transmission of human ascariasis in the UK, a zoonotic spill-over from farmed pigs, which expose deficits in WASH but can be addressed by administration of anti-parasitic drugs in people and pigs.

Certain parasites, such as the trematodes, act as public health thorns that open-up prickly gaps in WASH, especially parasitic larval stages highly adapted to transmission in water as “Human fascioliasis infection sources, their diversity, incidence factors, analytical methods and prevention measures” relates. The human liver fluke, Fasciola hepatica, can contaminate in subtle, but significant ways, all water used by humans and animals. The same is true for certain protozoan disease, such as giardiasis as “Giardia duodenalis in the UK: current knowledge of risk factors and public health implications” points out. Similarly, cryptosporidiosis, which is mainly present in livestock, points out the risks to the public, farmers and veterinarians when in close range with infected animals; so please remember to wash your hands even at public petting farms!

We hope you enjoy reading these freely available articles in the collection. We welcome any pointers on Twitter that you may wish to add as to how these parasites, in contrast to other pathogens, are exquisitely challenging to handwashing interventions. 

Access Parasitology‘s free Global Handwashing Day Collection here.