R E V I E W Using the tetravalent meningococcal polysaccharide-protein conjugate vaccine in the prevention of meningococcal disease Sanford R Kimmel University of Toledo College of Medicine, Department of Family Medicine, Toledo, OH, USA Correspondence: Sanford R Kimmel University of Toledo College of Medicine, Department of Family Medicine, Dowling Hall Room 2240, Mail Stop 1179, 3000 Arlington Avenue,Toledo, OH 43614-2598, USA Tel +1 419 383 5581 Fax +1 419 383 3158 Email sanford.kimmel@utoledo.edu Abstract: Invasive meningococcal disease occurs worldwide causing an estimated 50,000–135,000 deaths each year in addition to signiﬁcant sequelae. In developed countries the disease is usually sporadic but outbreaks and epidemics, usually due to serogroups B and C, have occurred. In the US, an increasing number of cases are due to serogroup Y. In developing nations, epidemics due to serogroups A and more recently W-135, are common. The tetravalent meningococcal conjugate vaccine to serogroups A, C, Y, and W-135 (MCV4) has been demonstrated to be highly immunogenic and promote immune memory. This article will describe the rationale for the vaccine and its potential role to signiﬁcantly decrease mortality and morbidity of meningococcal disease in those areas and populations at greatest risk from these serogroups. Keywords: meningococcal disease, tetravalent meningococcal conjugate vaccine, serogroup Epidemiology and pathogenesis Neisseria meningitidis is an aerobic, gram negative diplococcus that colonizes the nasopharynx of humans and is transmitted by respiratory tract droplets (Gardner 2006). Almost all human disease is caused by 5 of the 13 serogroups: A, B, C, Y, and W-135. Worldwide, approximately 500,000 cases of invasive meningococcal disease (IMD) occur annually resulting in an estimated 50,000–135,000 deaths per year (Pollard 2004; Borrow and Miller 2006). The incidence of the disease in developed countries varies from 0.5 to 1.1 per 100,000 people per year in the US (Gardner 2006) to 3.6 cases per 100,000 in England and Wales (Pollard 2004). In 2006, the estimated incidence of probable and conﬁrmed IMD varied from 0.30 and 0.35 per 100,000 people in Italy and Hungary, respectively, to 4.96 and 8.90 per 100,000 in Ireland and Malta, respec- tively (EU-IBIS 2006). In the US, over 98% of cases of IMD are sporadic (Bilukha and Rosenstein 2005) but the disease is epidemic in many parts of the world. The inﬂuence of serogroups in causing meningococcal disease varies according to year, geography, and, in some cases, ethnic and socioeconomic factors. Sero- groups B and C cause most cases of sporadic and rare epidemic disease in developed countries. Serogroups B, C, W-135, and Y comprised 61%, 32.2% , 3.2%, and 2.9% of meningococcal isolates, respectively, from IMD patients in the Czech Republic, Greece, and Norway (Yazdankhah et al 2004). Among IMD isolates, serogroup B predominated in Greece and Norway while serogroup C predominated in in the Czech Republic (Yazdankhah et al 2004). Serogroup A and recently W-135 cause most cases of epidemic disease in sub-Saharan Africa (almost 1000 cases per 100,000 population) (Pollard 2004). Serogroup W-135 meningococcal disease has been reported in pilgrims returning from the Hajj in Saudi Arabia and in their contacts (MMWR 2001b; Hahne 2002). Serogroup Y accounted for only 2% of meningococcal disease in the US from 1988 to 1991 but accounted for 40% of cases during 2006, while serogroups B and C Therapeutics and Clinical Risk Management 2008:4(4) 739–745 © 2008 Dove Medical Press Limited. All rights reserved 739