Four-month outbreak of invasive meningococcal disease caused by a rare serogroup B strain, identified through the use of molecular PorA subtyping, England, 2013 Chatt, C and Gajraj, R and Hawker, J and Neal, K and Tahir, M and Lawrence, M and Gray, S J and Lucidarme, J and Carr, A D and Clark, S A and Fowler, T, Eurosurveillance, 19, 20949 (2014), https://doi.org/10.2807/1560-7917.ES2014.19.44.20949