Polio
Infant being vaccinated with OPV in Delhi
The world's governments committed to global polio eradication in 1988, since when the annual number of paralytic cases has fallen from about 350,000 to just 950 in 2010. However, endemic transmission has continued in parts of South East Asia and Africa despite mass campaigns with oral poliovirus vaccine. Subsequent international spread of infection has led to polio outbreaks in countries previously free of wild-type poliovirus.
In collaboration with the World Health Organisation and academic centres in India and Africa we have carried out research to understand the causes of persistent poliovirus transmission in remaining endemic countries. We have also worked to better understand and predict the spread of polio and studied vaccine-derived polioviruses to reveal their clinical and epidemiological characteristics. Our work on poliovirus vaccines is described here.
Our work is relevant to vaccination policy. Dr Grassly is a member of the working group responsible for World Health Organisation position papers on poliovirus vaccines and more generally our group's research contributes to milestones and vaccination plans pursued by the Global Polio Eradication Initiative (e.g. Strategic Plan 2010-12).
Selected publications
Jenkins HE, Aylward RB, Gasasira A, Donnelly CA, Mwanza M, Corander J, Garnier S, Chauvin C, Abanida EA, Pate MA, Adu F, Baba M & Grassly NC Implications of a circulating vaccine-derived poliovirus in Nigeria. New Engl J Med 2010. 362: 2360-9. [full text]
Grassly NC, Jafari H, Bahl S, Durrani S, Wenger J, Sutter RW and Aylward RB Asymptomatic wild-type poliovirus infection among children with previous oral poliovirus vaccination J Infect Dis 2010. 201: 1535-1543. pdf 
Grassly NC, Jafari H, Bahl S et al. Mucosal immunity following vaccination with monovalent and trivalent oral poliovirus vaccines in India. J Infect Dis 2009. 200: 794-801[full text]
Jenkins HE, Aylward RB, Gasasira A, Donnelly CA, Koleosho-Adelekan T, Abanida EA and Grassly NC The effectiveness of immunization against polio in Nigeria. New Engl J Med 2008. 359: 1666-1674. [full text]
Grassly NC, Wenger J, Durrani S, et al. Protective efficacy of a monovalent oral type 1 poliovirus vaccine: a case-control study. Lancet 2007. 369:1356-1362.
Grassly NC, Fraser C, Wenger J, et al. New strategies for the elimination of polio from India. Science 2006. 314:1150 - 1153. [full text link available from personal webpage]
