A catch-up campaign was used to offer MenACWY vaccine to all 14–18-year-old persons, with persons who left school in 2015 (17–18 years of age) given priority. In response, Public Health England introduced the MenACWY vaccine in the routine adolescent school program for 14- and 15-year-olds and first-year university students ( 8). Since 2009, although MenY disease has plateaued, capsular group W (MenW) disease has steadily increased because of the rapid expansion of hypervirulent strains belonging to the sequence type 11 clonal complex (MenW:ST-11) ( 5).Īnalysis of whole-genome sequence data has shown that isolates from the same MenW:ST-11 lineage, termed the South American/UK strain, are also endemic to Chile, Brazil, and Argentina ( 6) and were recently reported in Australia ( 7). This high level of MenY carriage was concomitant with a rise in disease caused by MenY strains in the United Kingdom ( 4). Meningococcal carriage was previously assessed in university students in the United Kingdom during 2009–10 at the University of Nottingham (UoN) when a high prevalence of capsular group Y (MenY) meningococcal carriage was detected ( 3). High carriage rates are particularly evident in semiclosed communities of young adults, such as university student populations, where persons live, work, and socialize together ( 2).
The main reservoir in most populations is asymptomatic pharyngeal carriage in older adolescents and young adults ( 1). Neisseria meningitidis causes severe sepsis and meningitis.