Chemoprophylaxis and vaccination in preventing subsequent cases of meningococcal disease in household contacts of a case of meningococcal disease: a systematic review.

Household contacts of an index case of invasive meningococcal disease (IMD) are at increased risk of acquiring disease. In revising WHO guidance on IMD in sub-Saharan Africa, a systematic review was undertaken to assess the effect of chemoprophylaxis and of vaccination in preventing subsequent cases of IMD in household contacts following an index case. A literature search for systematic reviews identified a single suitable review on chemoprophylaxis in 2004 (three studies meta-analysed). A search for primary research papers published since 2004 on chemoprophylaxis and without a date limit on vaccination was therefore undertaken. There were 2381 studies identified of which two additional studies met the inclusion criteria. The summary risk ratio for chemoprophylaxis vs. no chemoprophylaxis (four studies) in the 30-day period after a case was 0·16 [95% confidence interval (CI) 0·04-0·64, P = 0·008]; the number needed to treat to prevent one subsequent case was 200 (95% CI 111-1000). A single quasi-randomized trial assessed the role of vaccination. The risk ratio for vaccination vs. no vaccination at 30 days was 0·11 (95% CI 0·01-2·07, P = 0·14). The results support the use of chemoprophylaxis to prevent subsequent cases of IMD in household contacts of a case. Conclusions about the use of vaccination could not be drawn.