Carlos Chagas identifies a human case of a new disease

Once developed, the new radiation allowed physicians to see bones inside the living body without surgery.

While working in British-ruled India, he observed pigmented structures in the dissected mosquito.

The discovery helped establish the role of mosquitoes in malaria transmission; the full life cycle was clarified through later work.

The date later became World Mosquito Day, commemorating a result reached in India rather than Britain.

The work depended on Indian settings, patients and assistants, although standard retellings often focus almost entirely on Ross.

The young patient was the first documented human case of the disease later named after Chagas.

Chagas connected a parasitic organism, an insect vector and a human case in his research.

The 14 April diagnosis preceded later research into the diverse long-term effects of Chagas disease.

The fourteen-year-old patient was given a first pancreatic extract injection in Toronto.

The initial extract had only limited effect and caused a local reaction; a successful improved treatment followed later.