Epidemiology of Infant Meningococcal Disease in the United States, 2006-2012

BackgroundThe incidence of meningococcal disease is currently at historic lows in the United States; however, incidence remains highest among infants aged <1 year. With routine use of Haemophilus influenzae type b and pneumococcal vaccines in infants and children in the United States, Neisseria meningitidis remains an important cause of bacterial meningitis in young children.MethodsData were collected from active, population- and laboratory-based surveillance for N meningitidis conducted through Active Bacterial Core surveillance during 2006 through 2012. Expanded data collection forms were completed for infant cases identified in the surveillance area during 2006 through 2010.ResultsAn estimated 113 cases of culture-confirmed meningococcal disease occurred annually among infants aged <1 year in the United States from 2006 through 2012, for an overall incidence of 2.74 per 100,000 infants. Among these cases, an estimated 6 deaths occurred. Serogroup B was responsible for 64%, serogroup C for 12%, and serogroup Y for 16% of infant cases. Based on the expanded data collection forms, a high proportion of infant cases (36/58, 62%) had a smoker in the household and the socioeconomic status of the census tracts where infant meningococcal cases resided was lower compared with the other Active Bacterial Core surveillance areas and the United States as a whole.ConclusionsThe burden of meningococcal disease remains highest in young infants and serogroup B predominates. Vaccines that provide long-term protection early in life have the potential to reduce the burden of meningococcal disease, especially if they provide protection against serogroup B meningococcal disease

Current Epidemiology and Trends in Invasive Haemophilus influenzae Disease-United States, 2009-2015.

BackgroundFollowing Haemophilus influenzae serotype b (Hib) conjugate vaccine introduction in the 1980s, Hib disease in young children dramatically decreased, and epidemiology of invasive H. influenzae changed.MethodsActive surveillance for invasive H. influenzae disease was conducted through Active Bacterial Core surveillance sites. Incidence rates were directly standardized to the age and race distribution of the US population.ResultsDuring 2009-2015, the estimated mean annual incidence of invasive H. influenzae disease was 1.70 cases per 100000 population. Incidence was highest among adults aged ≥65 years (6.30) and children aged <1 year (8.45); many cases in infants aged <1 year occurred during the first month of life in preterm or low-birth-weight infants. Among children aged <5 years (incidence: 2.84), incidence was substantially higher in American Indian and Alaska Natives AI/AN (15.19) than in all other races (2.62). Overall, 14.5% of cases were fatal; case fatality was highest among adults aged ≥65 years (20%). Nontypeable H. influenzae had the highest incidence (1.22) and case fatality (16%), as compared with Hib (0.03; 4%) and non-b encapsulated serotypes (0.45; 11%). Compared with 2002-2008, the estimated incidence of invasive H. influenzae disease increased by 16%, driven by increases in disease caused by serotype a and nontypeable strains.ConclusionsInvasive H. influenzae disease has increased, particularly due to nontypeable strains and serotype a. A considerable burden of invasive H. influenzae disease affects the oldest and youngest age groups, particularly AI/AN children. These data can inform prevention strategies, including vaccine development

Effect of use of 13-valent pneumococcal conjugate vaccine in children on invasive pneumococcal disease in children and adults in the USA: analysis of multisite, population-based surveillance

BackgroundIn 2000, seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the USA and resulted in dramatic reductions in invasive pneumococcal disease (IPD) and moderate increases in non-PCV7 type IPD. In 2010, PCV13 replaced PCV7 in the US immunisation schedule. We aimed to assess the effect of use of PCV13 in children on IPD in children and adults in the USA.MethodsWe used laboratory-based and population-based data on incidence of IPD from the Active Bacterial Core surveillance (part of the Centers for Disease Control and Prevention's Emerging Infections Program) in a time-series model to compare rates of IPD before and after the introduction of PCV13. Cases of IPD between July 1, 2004, and June 30, 2013, were classified as being caused by the PCV13 serotypes against which PCV7 has no effect (PCV13 minus PCV7). In a time-series model, we used an expected outcomes approach to compare the reported incidence of IPD to that which would have been expected if PCV13 had not replaced PCV7.FindingsCompared with incidence expected among children younger than 5 years if PCV7 alone had been continued, incidence of IPD overall declined by 64% (95% interval estimate [95% IE] 59-68) and IPD caused by PCV13 minus PCV7 serotypes declined by 93% (91-94), by July, 2012, to June, 2013. Among adults, incidence of IPD overall also declined by 12-32% and IPD caused by PCV13 minus PCV7 type IPD declined by 58-72%, depending on age. We estimated that over 30 000 cases of IPD and 3000 deaths were averted in the first 3 years after the introduction of PCV13.InterpretationPCV13 reduced IPD across all age groups when used routinely in children in the USA. These findings provide reassurance that, similar to PCV7, PCVs with additional serotypes can also prevent transmission to unvaccinated populations.FundingCenters for Disease Control and Prevention

Effect of use of 13-valent pneumococcal conjugate vaccine in children on invasive pneumococcal disease in children and adults in the USA: analysis of multisite, population-based surveillance

BackgroundIn 2000, seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the USA and resulted in dramatic reductions in invasive pneumococcal disease (IPD) and moderate increases in non-PCV7 type IPD. In 2010, PCV13 replaced PCV7 in the US immunisation schedule. We aimed to assess the effect of use of PCV13 in children on IPD in children and adults in the USA.MethodsWe used laboratory-based and population-based data on incidence of IPD from the Active Bacterial Core surveillance (part of the Centers for Disease Control and Prevention's Emerging Infections Program) in a time-series model to compare rates of IPD before and after the introduction of PCV13. Cases of IPD between July 1, 2004, and June 30, 2013, were classified as being caused by the PCV13 serotypes against which PCV7 has no effect (PCV13 minus PCV7). In a time-series model, we used an expected outcomes approach to compare the reported incidence of IPD to that which would have been expected if PCV13 had not replaced PCV7.FindingsCompared with incidence expected among children younger than 5 years if PCV7 alone had been continued, incidence of IPD overall declined by 64% (95% interval estimate [95% IE] 59-68) and IPD caused by PCV13 minus PCV7 serotypes declined by 93% (91-94), by July, 2012, to June, 2013. Among adults, incidence of IPD overall also declined by 12-32% and IPD caused by PCV13 minus PCV7 type IPD declined by 58-72%, depending on age. We estimated that over 30 000 cases of IPD and 3000 deaths were averted in the first 3 years after the introduction of PCV13.InterpretationPCV13 reduced IPD across all age groups when used routinely in children in the USA. These findings provide reassurance that, similar to PCV7, PCVs with additional serotypes can also prevent transmission to unvaccinated populations.FundingCenters for Disease Control and Prevention

Current Epidemiology and Trends in Invasive Haemophilus influenzae Disease—United States, 2009–2015

BackgroundFollowing Haemophilus influenzae serotype b (Hib) conjugate vaccine introduction in the 1980s, Hib disease in young children dramatically decreased, and epidemiology of invasive H. influenzae changed.MethodsActive surveillance for invasive H. influenzae disease was conducted through Active Bacterial Core surveillance sites. Incidence rates were directly standardized to the age and race distribution of the US population.ResultsDuring 2009-2015, the estimated mean annual incidence of invasive H. influenzae disease was 1.70 cases per 100000 population. Incidence was highest among adults aged ≥65 years (6.30) and children aged <1 year (8.45); many cases in infants aged <1 year occurred during the first month of life in preterm or low-birth-weight infants. Among children aged <5 years (incidence: 2.84), incidence was substantially higher in American Indian and Alaska Natives AI/AN (15.19) than in all other races (2.62). Overall, 14.5% of cases were fatal; case fatality was highest among adults aged ≥65 years (20%). Nontypeable H. influenzae had the highest incidence (1.22) and case fatality (16%), as compared with Hib (0.03; 4%) and non-b encapsulated serotypes (0.45; 11%). Compared with 2002-2008, the estimated incidence of invasive H. influenzae disease increased by 16%, driven by increases in disease caused by serotype a and nontypeable strains.ConclusionsInvasive H. influenzae disease has increased, particularly due to nontypeable strains and serotype a. A considerable burden of invasive H. influenzae disease affects the oldest and youngest age groups, particularly AI/AN children. These data can inform prevention strategies, including vaccine development