Figure 1.

Flow diagram of systematic review. ^aFour retrospective case series or studies [4, 9, 12, 14], 2 prospective observational studies [10, 11], 1 case-control study [15], 2 case reports [13, 16], and 1 review of autopsies [35]. ^bFour reported deaths were excluded from further review as sufficient individual patient data were not available [15]. ^cNineteen deaths occurred in Sabah and 7 in Sarawak, Malaysia, all during 2001–2014.