important research interest of his for several years, leading to the demonstration of human-avian hybrid viruses and the suggestion that avian influenza could be involved in human pandemics. The importance of Pereira's work was recognised in 1961, when he became a director of the World Influenza Centre in Mill Hill at the time of the Asian flu pandemic. He was able to plot the changes in the virus using strains sent from centres around the world. The Hong Kong flu pandemic in 1968 was an opportunity to demonstrate that new identifiable strains were responsible. With his wife Peggy, who as Head of Virology at the PHLS in Colindale had responsibility for influenza surveillance in England and Wales, methods were developed to identify new strains and indicate those required for future vaccines. Influenza He spent three months at the Universidad de Montevideo in Uruguay in 1963, and spent time at the University of São Paulo in 1965. Pereira left the Virology department at the National Institute for Medical Research in Mill Hill in 1973 to work at the Pirbright Institute (then the Institute for Animal Health), due to increased interest in comparative virology. Using contacts from his old department, he headed the new department of epidemiology at the World Reference Laboratory for Foot and Mouth Disease. The department focused on researching exotic viral diseases and studying pathogenesis and vaccine development. Free from time-consuming administration, he enjoyed doing research there. That year, Pereira was elected a Fellow of the Royal Society. Around this time, one of his daughters died. Pereira retired from the Pirbright Institute in 1979 and became a scientific consultant at the Instituto Oswaldo Cruz, where he worked on the AIDS virus. Pereira travelled between the UK and Brazil around this time, spending time with family in each country. He assisted and advised young scientists about local health problems between 1979 and 1985, developing new methods and discovering new viruses with his colleagues. Pereira's wife, Peggy, organised a study of viruses which caused acute respiratory illnesses in Rio de Janeiro children at this time. They contributed to a World Health Organization meeting in Rio about the respiratory diseases programme. Later life Shortly after Peggy retired from the Public Health Laboratory Service in 1987, she and Pereira were involved in a serious car accident in Rio de Janeiro. Peggy was killed, and he was seriously injured. During the late 1980s, Pereira