Louisville Medicine Volume 63, Issue 5 | Page 11

VACCINE UPDATE ON MENINGOCOCCAL DISEASE Stanley A. Gall, MD M eningococcal disease comprises a spectrum of infections caused by Neisseria meningitidis and includes meningitis (50.2 percent), bacteremia (37.5 percent) or bacteremia pneumonia (9.2 percent). (1) (2) Neisseria meningitis colonizes the mucosal surfaces of the nasopharynx and is transmitted by large droplet respiratory tract secretions. Nasopharyngeal carriage rates are highest in adolescents and young adults. (3) It is estimated that 800-1,200 cases of meningococcal disease occurred annually during 2005-2011 representing an incidence of 0.3 cases per 100,000 populations. (4) Incidence has decreased annually since a peak in the late 1990s. There has been a decrease from 1.1 cases per 100,000 populations to 0.4 cases per 100,000 populations (64 percent). Although the incidence is at historical lows, the overall case fatality remains at 10-15 percent, and 1119 percent of the survivors have long term sequelae (neurologic disability, limb or digit loss and hearing loss).(5) Serogroups B, C and Y are the major causes of meningococcal disease in the United States, each causing approximately one-third of the cases. However, they vary by age. About 60 percent of disease among children aged 0-59 months is caused by serogroup B, which is not prevented by older vaccines but is included in recently recommended vaccines. Serogroups C, Y or W cause 73 percent of all cases of meningococcal disease among persons age 11 or greater. (4) The incidence of meningococcal disease peaks among persons in three age groups :( 4) -- infants and children aged <5 (serogroups C and Y in infants, 60 percent serogroup B up to age 5) -- adolescents and young adults aged 16-25 years -- adults ≥ 65 years of age (^0 percent serogroup Y and 43 percent with bacteremia pneumonia). The highest case fatality rate nearly 24 percent is seen in those older than 65. CURRENT MENINGOCOCCAL VACCINES AVAILABLE IN THE UNITED STATES Trade Name Type of Vaccine Meningococcal Sero-Types covered Bexsero recombinant (Men B) B Menactra conjugate (Men ACWY) A, C, W, Y MenHibrix conjugate C, Y and Haemophilus influenza type b Menomune polysaccharide (MPSV4) A, C, W, Y Menveo conjugate (Men ACWY) A, C, W, Y Trumenba recombinant (Men B) B OCTOBER 2015 9