Unintended consequences of immunisation

Readers of The Lancet may have noticed that an unlooked-for benefit of the introduction of the new immunisation against group B meningococcal disease is partial but significant protection against gonorrhoea (DOI: 10.1016/S0140-6736(17)31449-6), identified in New Zealand. Closer to home though, there are less benign issues with Bexsero: the consequences of the febrile response to the vaccine are such that we have three related papers and an accompanying Editorial. Nainani et al, with data from Oxford, and Kapur et al from Belfast, have analysed the impact on their respective emergency departments, while Murdoch et al have looked at hospital admissions in Scotland. In a nutshell, a proportion of infants immunised with Bexsero became sufficiently feverish and unwell that they pitched up to emergency departments in the days following the injection. Some ended up admitted and given antibiotics just in case they had a bacterial infection; indeed many of these infants are over the bar in relation to the current NICE guidance ‘Fever in under 5 s: assessment and initial management’ (CG160). So in exchange for the lives saved (and later the gonorrhoea prevented) there is some short term increased ‘unnecessary’ …