Table 1. Description of serogroup B invasive meningococcal disease cases in Beaujolais, France, February–March 2016 (n = 4).

	Cluster 1		Cluster 2 (co-primary cases)
	Case 1	Case 2	Case 3a	Case 3b
Date of hospitalisation	29 Feb 2016	3 Mar 2016	19 Mar 2016	19 Mar 2016
Age (years)	17	17	4	3
Sex	Male	Female	Female	Female
Symptoms	Meningitis, petechial rash	Meningitis, shock, coma	Purpura fulminans, multiple organ failure	Meningitis
Relations between cases	They were present at the same local community ball on 20 Feb 2016, but there was no direct or indirect contact identified between the two cases. No community identified.		They were friends, in the same class at the primary school. Same community identified.