The period 1875–1925 was remarkable in the history of parasitology mainly for the elucidation of the life cycles of parasites causing important parasitic diseases and the incrimination of vectors in their transmission. These discoveries were made by a small number of scientists working in the tropics a number of whom were Scots. Sir Patrick Manson, the discoverer of the mosquito transmission of filarial worms, was instrumental in directly or indirectly encouraging other Scots including Douglas Argyll-Robertson, David Blacklock, David Bruce, David Cunningham, Robert Leiper, William Leishman, George Low, Muriel Robertson and Ronald Ross, who all made significant discoveries across a wide spectrum of tropical diseases. Among these, William Leishman, Robert Leiper and Muriel Robertson were all graduates of the University of Glasgow and their achievements in the fields of leishmaniasis, schistosomiasis, dracunculiasis and African sleeping sickness, together with subsequent developments in these fields, are the subjects of the ten papers in this Special Issue of Parasitology.

The period 1875–1925 was remarkable in the history of parasitology partly because of the number of significant discoveries made, especially the elucidation of important life cycles, and partly because of the achievements of the clinicians and scientists who made these discoveries. What is remarkable is that so many of these individuals were Scots. Preeminent in this pantheon was Patrick Manson, who not only discovered the mosquito transmission of filarial worms but was instrumental in directly encouraging others to make significant discoveries in the fields of malaria, Guinea worm disease (dracunculiasis), onchocerciasis, loiasis and schistosomiasis and, indirectly, sleeping sickness and leishmaniasis. This chapter describes and discusses the contributions made by Douglas Argyll-Robertson, Donald Blacklock, David Bruce, David Cunningham, Robert Leiper, William Leishman, George Low, Patrick Manson, Muriel Robertson and Ronald Ross together with short biographical notes.

Famous for the discovery of the parasite, Leishmania, named after him, and the invention of Leishman's stain, William Boog Leishman should perhaps be better known for his work in military and public health, particularly the prevention of typhoid. Leishman was a Medical Officer in the British Army from 1887 until his death in 1926. His early research was on diseases affecting troops posted to stations within the British Empire. He saw cases of Leishmaniasis while stationed in India, and was able to identify the causative organism from his detailed records of his observations. Leishman's most important contribution to public health, however, was his work with typhoid, a major cause of morbidity and mortality in the army. Leishman planned experiments and the collection of data to demonstrate the efficacy of anti-typhoid inoculation and, using his considerable political skills, advocated the adoption of the vaccine. He planned for the inoculation of troops in an emergency so, when war broke out in 1914, the vaccine was available to save thousands of lives. Leishman's colleagues and mentors included Ronald Ross and Almroth Wright. Leishman was less outspoken than either Ross or Wright; this paper shows how the different contributions of the three men overlapped.

Muriel Robertson (1883–1973) was a pioneering protozoologist who made a staggering number of important contributions to the fields of parasitology, bacteriology and immunology during her career, which spanned nearly 60 years. These contributions were all the more remarkable given the scientific and social times in which she worked. While Muriel is perhaps best known for her work on the life cycle and transmission of the African trypanosome, Trypanosoma brucei, which she carried out in Uganda at the height of a major Sleeping Sickness epidemic, her work on the Clostridia during the First and Second World Wars made significant contributions to the understanding of anaerobes and to the development of anti-toxoid vaccines, and her work on the immunology of Trichomonas foetus infections in cattle, carried out in collaboration with the veterinarian W. R. Kerr, resulted in changes in farming practices that very quickly eradicated trichomoniasis from cattle herds in Northern Ireland. The significance of her work was recognized with the award of Fellow of the Royal Society in 1947 and an Honorary Doctorate of Law from the University of Glasgow, where she had earlier studied, in 1948.

Part of Robert T. Leiper's (1881–1969) lasting legacy in medical helminthology is grounded on his pioneering work on schistosomiasis (Bilharzia). Having undertaken many expeditions to the tropics, his fascination with parasite life cycles typically allowed him to devise simple preventive measures that curtailed transmission. Building on his formative work with others in Africa and Asia, and again in Egypt in 1915, he elucidated the life cycles of African schistosomes. His mandate, then commissioned by the British War Office, was to prevent and break transmission of this disease in British troops. This he did by raising standing orders based on simple water hygiene measures. Whilst feasible in military camp settings, today their routine implementation is sadly out of reach for millions of Africans living in poverty. Whilst we celebrate the centenary of Leiper's research we draw attention to some of his lesser known colleagues, then focus on schistosomiasis in Uganda discussing why expanded access to treatment with praziquantel is needed now. Looking to WHO 2020 targets for neglected tropical diseases, we introduce COUNTDOWN, an implementation research consortium funded by DFID, UK, which fosters the scale-up of interventions and confirm the current relevance of Leiper's original research.

Early in the history of schistosomiasis research, children under 5 years of age were known to be infected. Although this problem was recognized over 100 years ago, insufficient action has been taken to address this issue. Under current policy, such infected children only receive their first antiparasitic treatment (praziquantel – PZQ) upon entry into primary school as current mass drug administration programmes typically target school-aged children. For many infected children, they will wait up to 6 years before receiving their first medication and significant schistosomiasis-related morbidity may have already established. This inequity would not be accepted for other diseases. To unveil some of the reasons behind this neglect, it is paramount to understand the intricate historical relationship between schistosomiasis and British Imperial medicine, to underline its lasting influence on today's public health priorities. This review presents a perspective on the historical neglect of paediatric schistosomiasis, focusing on important gaps that persist from the early days after discovery of this parasite. Looking to end this inequity, we address several issues that need to be overcome to move forward towards the lasting success of schistosomiasis control and elimination efforts.

Schistosomiasis, commonly known as bilharzia, is a parasitic disease prevalent in Africa, Asia and South America. The majority of the cases occur in Sub-Saharan Africa where schistosomiasis is a major public health problem impacting on child health and development as well as adult health when infections become chronic. Control of schistosomiasis is by treatment of infected people with the antihelminthic drug praziquantel. Current schistosome control programmes advocated by the World Health Assembly in 2001 are aimed at regular school-based integrated deworming strategies in order to reduce development of severe morbidity, promote school health and to improve cognitive potential of children. Several countries in Africa have now embarked on national scale deworming programmes treating millions of children exposed to schistosomiasis in endemic areas without prior diagnosis of infection through mass drug administration programmes. Implementing such control programmes requires a concerted effort between scientists, policy makers, health practitioners and several other stake holders and of course a receptive community. This paper considers the contributions to global schistosome control efforts made by research conducted in Zimbabwe and the historical context and developments leading to the national schistosomiasis control programme in Zimbabwe giving an example of Getting Research into Policy and Practice.

Schistosomiasis in China has been substantially reduced due to an effective control programme employing various measures including bovine and human chemotherapy, and the removal of bovines from endemic areas. To fulfil elimination targets, it will be necessary to identify other possible reservoir hosts for Schistosoma japonicum and include them in future control efforts. This study determined the infection prevalence of S. japonicum in rodents (0–9·21%), dogs (0–18·37%) and goats (6·9–46·4%) from the Dongting Lake area of Hunan province, using a combination of traditional coproparasitological techniques (miracidial hatching technique and Kato-Katz thick smear technique) and molecular methods [quantitative real-time PCR (qPCR) and droplet digital PCR (ddPCR)]. We found a much higher prevalence in goats than previously recorded in this setting. Cattle and water buffalo were also examined using the same procedures and all were found to be infected, emphasising the occurrence of active transmission. qPCR and ddPCR were much more sensitive than the coproparasitological procedures with both KK and MHT considerably underestimating the true prevalence in all animals surveyed. The high level of S. japonicum prevalence in goats indicates that they are likely important reservoirs in schistosomiasis transmission, necessitating their inclusion as targets of control, if the goal of elimination is to be achieved in China.

Guinea worm disease, dracunculiasis or dracontiasis, is an ancient disease with records going back over 4500 years, but until the beginning of the 20th century, little was known about its life cycle, particularly how humans became infected. In 1905, Robert Thomas Leiper was sent by the British colonial authorities to West Africa to investigate the spread of Guinea worm disease and to recommend measures to prevent it. While carrying out his investigations, he made important contributions to the aetiology, epidemiology and public health aspects of Guinea worm disease and provided definitive answers to many outstanding questions. First, he tested the validity of previous theories; second, he confirmed the role of water fleas, which he identified as Cyclops, as the intermediate hosts in the life cycle; third, he investigated the development of the parasite in its intermediate host; and fourth, he recommended measures to prevent the disease.

[The crustacean Order Cyclopoida in the Family Cyclopidae contains 25 genera, including Cyclops which itself contains over 400 species and may not even be a valid taxon. It is not known how many of these species (or indeed species belonging to related genera) can act as intermediate hosts of Dracunculus medinensis nor do we know which species Fedchenko, Leiper and other workers used in their experiments. It is, therefore, best to use the terms copepod, or copopoid crustacean rather than Cyclops in scientific texts. In this paper, these crustaceans are referred to as copepods except when referring to an original text.]

Leiper described the remarkable changes that took place when an infected copepod was placed in a dilute solution of hydrochloric acid; the copepod was immediately killed, but the Dracunculus larvae survived and were released into the surrounding water. From this, he concluded that if a person swallowed an infected copepod, their gastric juice would produce similar results. He next infected monkeys by feeding them copepods infected with Guinea worm larvae, and thus conclusively demonstrated that humans became infected by accidentally ingesting infected crustaceans. Based on these conclusions, he advocated a number of control policies, including avoidance of contaminated drinking water or filtering it, and these preventive measures paved the way for further research. The challenge to eradicate Guinea worm disease was not taken up until about seven decades later since when, with the support of a number of governmental and non-governmental organizations, the number of cases has been reduced from an estimated 3·5 million in 1986 to 25 in 2016 with the expectation that this will eventually lead to the eradication of the disease.

Robert Leiper is best known for his discoveries in the fields of Guinea worm and schistosomiasis, but he also made major contributions to parasitology during his career as helminthologist and later Professor of Helminthology at the London School of (Hygiene and) Tropical Medicine. He was particularly involved in establishing the London School's Winches Farm Field Station and stimulating the research carried out there, work that has made a number of important contributions to our understanding of parasites. Leiper founded the Commonwealth Bureau of Agricultural Parasitology and was also instrumental in initiating, and editing, the Journal of Helminthology, Helminthological Abstracts and establishing, indirectly, Protozoological Abstracts.

Dr David Livingstone died on May 1st 1873. He was 60 years old and had spent much of the previous 30 years walking across large stretches of Southern Africa, exploring the terrain he hoped could provide new environments in which Europeans and Africans could cohabit on equal terms and bring prosperity to a part of the world he saw ravaged by the slave trade. Just days before he died, he wrote in his journal about the permanent stream of blood that he was emitting related to haemorrhoids and the acute intestinal pain that had left him incapable of walking. What actually killed Livingstone is unknown, yet the years spent exploring sub-Saharan Africa undoubtedly exposed him to a gamut of parasitic and other infectious diseases. Some of these we can be certain of. He wrote prolifically and described his encounters with malaria, relapsing fevers, parasitic helminths and more. His graphic writing allows us to explore his own encounters with tropical diseases and how European visitors to Africa considered them at this time. This paper outlines Livingstone's life and his contributions to understanding parasitic diseases.