Search

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

Active Bacterial Core surveillance (ABCs) was established in 1995 as part of the Centers for Disease Control and Prevention Emerging Infections Program (EIP) network to assess the extent of invasive bacterial infections of public health importance. ABCs is distinctive among surveillance systems because of its large, population-based, geographically diverse catchment area; active laboratory-based identification of cases to ensure complete case capture; detailed collection of epidemiologic information paired with laboratory isolates; infrastructure that allows for more in-depth investigations; and sustained commitment of public health, academic, and clinical partners to maintain the system. ABCs has directly affected public health policies and practices through the development and evaluation of vaccines and other prevention strategies, the monitoring of antimicrobial drug resistance, and the response to public health emergencies and other emerging infections.

Objectives: Routine surveillance for streptococcal toxic shock syndrome (STSS), a severe manifestation of invasive group A Streptococcus (GAS) infections, likely underestimates its true incidence. The objective of our study was to evaluate routine identification of STSS in a national surveillance system for invasive GAS infections. Methods: Active Bacterial Core surveillance (ABCs) conducts active population-based surveillance for invasive GAS disease in selected US counties in 10 states. We categorized invasive GAS cases with a diagnosis of STSS made by a physician as STSS–physician and cases that met the Council of State and Territorial Epidemiologists (CSTE) clinical criteria for STSS based on data in the medical record as STSS–CSTE. We evaluated agreement between the 2 methods for identifying STSS and compared the estimated national incidence of STSS when applying proportions of STSS–CSTE and STSS–physician among invasive GAS cases from this study with national invasive GAS estimates for 2017. Results: During 2014-2017, of 7572 invasive GAS cases in ABCs, we identified 1094 (14.4%) as STSS–CSTE and 203 (2.7%) as STSS–physician, a 5.3-fold difference. Of 1094 STSS–CSTE cases, we identified only 132 (12.1%) as STSS–physician cases. Agreement between the 2 methods for identifying STSS was low (κ = 0.17; 95% CI, 0.14-0.19). Using ABCs data, we estimated 591 cases of STSS–physician and 3618 cases of STSS–CSTE occurred nationally in 2017. Conclusions: We found a large difference in estimates of incidence of STSS when applying different surveillance methods and definitions. These results should help with better use of currently available surveillance data to estimate the incidence of STSS and to evaluate disease prevention efforts, in addition to guiding future surveillance efforts for STSS. [ABSTRACT FROM AUTHOR]

Background Incidence of invasive disease due to Haemophilus influenzae serotype a (Hia) increased an average of 13% annually from 2002 through 2015. We describe clinical characteristics and adverse clinical outcomes of US invasive Hia cases detected through multistate surveillance during 2011–2015. Methods Medical record data were abstracted for cases reported in 8 jurisdictions conducting active population- and laboratory-based surveillance for invasive Hia disease across the United States. Isolates from sterile sites were serotyped using real-time polymerase chain reaction. Adverse clinical outcomes were defined as any possible complication of meningitis, bacteremic pneumonia, or bacteremia (including hearing loss and developmental delay, but excluding death) and were assessed at hospital discharge and one-year post-disease onset. Results During 2011–2015, 190 Hia cases were reported to the 8 participating sites; 169 (88.9%) had data abstracted. Many patients were aged <5 years (42.6%). Meningitis was the most common clinical presentation among those aged <1 year (71.4%); bacteremic pneumonia was the most common presentation among persons aged ≥50 years (78.7%). Overall, 95.9% of patients were hospitalized. Among those hospitalized, 47.5% were admitted to an intensive care unit and 6.2% died during hospitalization. At hospital discharge and one-year post-disease onset, adverse outcomes were identified in 17.7% and 17.8% of patients overall and in 43.9% and 48.5% of patients with meningitis (primarily children). Conclusions Hia infection can cause severe disease that requires hospitalization and may also cause short- and long-term adverse clinical outcomes, especially among children. Novel vaccines could prevent morbidity and mortality. [ABSTRACT FROM AUTHOR]

Background Reported outbreaks of invasive group A Streptococcus (iGAS) infections among people who inject drugs (PWID) and people experiencing homelessness (PEH) have increased, concurrent with rising US iGAS rates. We describe epidemiology among iGAS patients with these risk factors. Methods We analyzed iGAS infections from population-based Active Bacterial Core surveillance (ABCs) at 10 US sites from 2010 to 2017. Cases were defined as GAS isolated from a normally sterile site or from a wound in patients with necrotizing fasciitis or streptococcal toxic shock syndrome. GAS isolates were emm typed. We categorized iGAS patients into four categories: injection drug use (IDU) only, homelessness only, both, and neither. We calculated annual change in prevalence of these risk factors using log binomial regression models. We estimated national iGAS infection rates among PWID and PEH. Results We identified 12 386 iGAS cases; IDU, homelessness, or both were documented in ~13%. Skin infections and acute skin breakdown were common among iGAS patients with documented IDU or homelessness. Endocarditis was 10-fold more frequent among iGAS patients with documented IDU only versus those with neither risk factor. Average percentage yearly increase in prevalence of IDU and homelessness among iGAS patients was 17.5% and 20.0%, respectively. iGAS infection rates among people with documented IDU or homelessness were ~14-fold and 17- to 80-fold higher, respectively, than among people without those risks. Conclusions IDU and homelessness likely contribute to increases in US incidence of iGAS infections. Improving management of skin breakdown and early recognition of skin infection could prevent iGAS infections in these patients. [ABSTRACT FROM AUTHOR]

Background Haemophilus influenzae serotype a (Hia) can cause invasive disease similar to serotype b; no Hia vaccine is available. We describe the epidemiology of invasive Hia disease in the United States overall and specifically in Alaska during 2008–2017. Methods Active population- and laboratory-based surveillance for invasive Hia disease was conducted through Active Bacterial Core surveillance sites and from Alaska statewide invasive bacterial disease surveillance. Sterile-site isolates were serotyped via slide agglutination or real-time polymerase chain reaction. Incidences in cases per 100 000 were calculated. Results From 2008 to 2017, an estimated average of 306 invasive Hia disease cases occurred annually in the United States (estimated annual incidence: 0.10); incidence increased by an average of 11.1% annually. Overall, 42.7% of cases were in children aged <5 years (incidence: 0.64), with highest incidence among children aged <1 year (1.60). Case fatality was 7.8% overall and was highest among adults aged ≥65 years (15.1%). Among children aged <5 years, the incidence was 17 times higher among American Indian and Alaska Native (AI/AN) children (8.29) than among children of all other races combined (0.49). In Alaska, incidences among all ages (0.68) and among children aged <1 year (24.73) were nearly 6 and 14 times higher, respectively, than corresponding US incidences. Case fatality in Alaska was 10.2%, and the vast majority (93.9%) of cases occurred among AI/AN. Conclusions Incidence of invasive Hia disease has increased since 2008, with the highest burden among AI/AN children. These data can inform prevention strategies, including Hia vaccine development. [ABSTRACT FROM AUTHOR]

Background Few data on intracranial group A Streptococcus (GAS) infection in children are available. Here, we describe the demographic, clinical, and diagnostic characteristics of 91 children with intracranial GAS infection. Methods Cases of intracranial GAS infection in persons ≤18 years of age reported between 1997 and 2014 were identified by the Centers for Disease Control and Prevention's population- and laboratory-based Active Bacterial Core surveillance (ABCs) system. Medical charts were abstracted using a active, standardized case report form. All available isolates were emm typed. US census data were used to calculate rates. Results ABCs identified 2596 children with invasive GAS infection over an 18-year period; 91 (3.5%) had an intracranial infection. Intracranial infections were most frequent during the winter months and among children aged <1 year. The average annual incidence was 0.07 cases per 100000 children. For 83 patients for whom information for further classification was available, the principal clinical presentations included meningitis (35 [42%]), intracranial infection after otitis media, mastoiditis, or sinusitis (34 [41%]), and ventriculoperitoneal shunt infection (14 [17%]). Seven (8%) of these infections progressed to streptococcal toxic shock syndrome. The overall case fatality rate was 15%. GAS emm types 1 (31% of available isolates) and 12 (13% of available isolates) were most common. Conclusions Pediatric intracranial (GAS) infections are uncommon but often severe. Risk factors for intracranial GAS infection include the presence of a ventriculoperitoneal shunt and contiguous infections in the middle ear or sinuses. [ABSTRACT FROM AUTHOR]

We describe 2 human cases of infection with a new Neisseria species (putatively N. brasiliensis), 1 of which involved bacteremia. Genomic analyses found that both isolates were distinct strains of the same species, were closely related to N. iguanae, and contained a capsule synthesis operon similar to N. meningitidis. [ABSTRACT FROM AUTHOR]

Whole-genome sequencing (WGS) is invaluable for studying the epidemiology of meningococcal disease. Here we provide a perspective on the use of WGS for meningococcal molecular surveillance and outbreak investigation, where it helps to characterize pathogens, predict pathogen traits, identify emerging pathogens, and investigate pathogen transmission during outbreaks. Standardization of WGS workflows has facilitated their implementation by clinical and public health laboratories (PHLs), but further development is required for metagenomic shotgun sequencing and targeted sequencing to be widely available for culture-free characterization of bacterial meningitis pathogens. Internet-accessible servers are being established to support bioinformatics analysis, data management, and data sharing among PHLs. However, establishing WGS capacity requires investments in laboratory infrastructure and technical knowledge, which is particularly challenging in resource-limited regions, including the African meningitis belt. Strategic WGS implementation is necessary to monitor the molecular epidemiology of meningococcal disease in these regions and construct a global view of meningococcal disease epidemiology. [ABSTRACT FROM AUTHOR]

Background. Invasive group A Streptococcus (GAS) infections are associated with significant morbidity and mortality rates. We report the epidemiology and trends of invasive GAS over 8 years of surveillance. Methods. From January 2005 through December 2012, we collected data from the Centers for Disease Control and Prevention's Active Bacterial Core surveillance, a population-based network of 10 geographically diverse US sites (2012 population, 32.8 million). We defined invasive GAS as isolation of GAS from a normally sterile site or from a wound in a patient with necrotizing fasciitis (NF) or streptococcal toxic shock syndrome (STSS). Available isolates were emm typed.We calculated rates and made age- and race-adjusted national projections using census data. Results. We identified 9557 cases (3.8 cases per 100 000 persons per year) with 1116 deaths (case-fatality rate, 11.7%). The casefatality rates for septic shock, STSS, and NF were 45%, 38%, and 29%, respectively. The annual incidence was highest among persons aged ≥65 years (9.4/100 000) or <1 year (5.3) and among blacks (4.7/100 000). National rates remained steady over 8 years of surveillance. Factors independently associated with death included increasing age, residence in a nursing home, recent surgery, septic shock, NF, meningitis, isolated bacteremia, pneumonia, emm type 1 or 3, and underlying chronic illness or immunosuppression. An estimated 10 649-13 434 cases of invasive GAS infections occur in the United States annually, resulting in 1136-1607 deaths. In a 30-valent Mprotein vaccine, emm types accounted for 91% of isolates. Conclusions. The burden of invasive GAS infection in the United States remains substantial. Vaccines under development could have a considerable public health impact. [ABSTRACT FROM AUTHOR]

Background Recently, overall reductions for invasive MRSA infections (isolation from a normally sterile site) have slowed. Healthcare-associated community-onset (HACO) invasive methicillin-resistant Staphylococcus aureus (MRSA) infections are those with recent healthcare exposures who develop MRSA infection outside acute care hospitals, and account for most invasive MRSA infections. HACO incidence decreased 6.6% per year during 2005–2008; the contribution of persons who inject drugs (PWID) to HACO incidence has not been reported. Methods We identified invasive MRSA infections using active, population- and laboratory-based surveillance data during 2009–2017 from 25 counties in 7 sites (CA, CT, GA, MD, MN, NY, TN). Cases were HACO if culture was obtained from an outpatient, or ≤3 days after hospitalization in a patient with ≥1 of the following healthcare exposures (HEs): hospitalization, surgery, dialysis, or residence in a long-term care facility (LTCF) in the past year; or central vascular catheter ≤2 days before culture. We calculated incidence (per census population) overall, for PWID cases and others, and for cases associated with each HE. For each HE, we calculated the proportion of overall incidence increase for PWID and others. Results HACO MRSA incidence declined overall from 2009 to 2016 but increased from 2016 to 2017 overall (8%), for both PWID (63%) and others (5%) (figure). For both PWID and non-PWID, incidence from 2016 to 2017 increased by 0.5 cases/100,000 population; 91% of the increase in PWID occurred in cases with a past year hospitalization while 78% of the increase in cases not associated with injection drug use (IDU) occurred in cases with past year LTCF residence. Past year LTCF residence was less common among PWID (16%) then among other cases (38%, P < 0.01). Conclusion After years of declines, HACO MRSA incidence increased equally in 2017 for cases associated with IDU and in cases unrelated to IDU. Increases in PWID-associated cases account for half the overall increase, indicating that efforts to reduce HACO MRSA should address PWID risk factors as these infections may be due to self-injection. In addition, increases not related to PWID, if sustained, would be a reversal of historic trends and require further investigation into causes. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Introduction Candida is a leading cause of healthcare-associated bloodstream infections in the United States. Infants and children have unique risk factors for candidemia, and the Candida species distribution in this group is different that among adults; however, candidemia epidemiology in this population has not been described recently. Methods We conducted active population-based candidemia surveillance in 4 US metropolitan areas between 2009 and 2015. We calculated incidences among neonates (0–30 days old), infants (0–364 days old), and noninfant children (1–19 years old), documented their clinical features and antifungal drug resistance. Results We identified 307 pediatric candidemia cases. Incidence trends varied according to site, but overall, the incidence in neonates decreased from 31.5 cases/100000 births in 2009 to 10.7 to 11.8 cases/100000 births between 2012 and 2015, the incidence in infants decreased from 52.1 cases/100000 in 2009 to 15.7 to 17.5 between 2012 and 2015, and the incidence in noninfant children decreased steadily from 1.8 cases/100000 in 2009 to 0.8 in 2014. Common underlying conditions were prematurity in neonates (78%), surgery in nonneonate infants (38%), and malignancy in noninfant children (28%). Most neonate cases were caused by C albicans (67%), whereas non- C. albicans species accounted for 60% of cases in nonneonate infants and noninfant children. Fluconazole and echinocandin resistance rates were low overall. Thirty-day crude mortality was 13%. Conclusions The incidence of candidemia among neonates and infants declined after 2009 but remained stable from 2012 to 2015. Antifungal drug resistance is uncommon. Reasons for the lack of recent declines in neonatal and infant candidemia deserve further exploration. In this article, we describe the epidemiology of candidemia in children in the United States and on the basis of data collected as part of US Centers for Disease Control and Prevention active population-based surveillance. Trends in incidence, clinical characteristics, species distribution, and resistance rates are presented. [ABSTRACT FROM AUTHOR]

Abstract: As reviewed in this paper, meningococcal disease epidemiology varies substantially by geographic area and time. The disease can occur as sporadic cases, outbreaks, and large epidemics. Surveillance is crucial for understanding meningococcal disease epidemiology, as well as the need for and impact of vaccination. Despite limited data from some regions of the world and constant change, current meningococcal disease epidemiology can be summarized by region. By far the highest incidence of meningococcal disease occurs in the meningitis belt of sub-Saharan Africa. During epidemics, the incidence can approach 1000 per 100,000, or 1% of the population. Serogroup A has been the most important serogroup in this region. However, serogroup C disease has also occurred, as has serogroup X disease and, most recently, serogroup W-135 disease. In the Americas, the reported incidence of disease, in the range of 0.3–4 cases per 100,000 population, is much lower than in the meningitis belt. In addition, in some countries such as the United States, the incidence is at an historical low. The bulk of the disease in the Americas is caused by serogroups C and B, although serogroup Y causes a substantial proportion of infections in some countries and W-135 is becoming increasingly problematic as well. The majority of meningococcal disease in European countries, which ranges in incidence from 0.2 to 14 cases per 100,000, is caused by serogroup B strains, particularly in countries that have introduced serogroup C meningococcal conjugate vaccines. Serogroup B also predominates in Australia and New Zealand, in Australia because of the control of serogroup C disease through vaccination and in New Zealand because of a serogroup B epidemic. Based on limited data, most disease in Asia is caused by serogroup A and C strains. Although this review summarizes the current status of meningococcal disease epidemiology, the dynamic nature of this disease requires ongoing surveillance both to provide data for vaccine formulation and vaccine policy and to monitor the impact of vaccines following introduction. [Copyright &y& Elsevier]

Following an outbreak in Mecca Saudi Arabia in 2000, meningococcal strains expressing capsular group W (W) emerged as a major cause of invasive meningococcal disease (IMD) worldwide. The Saudi Arabian outbreak strain (Hajj clone) belonging to the ST-11 clonal complex (cc11) is similar to W cc11 causing occasional sporadic disease before 2000. Since 2000, W cc11 has caused large meningococcal disease epidemics in the African meningitis belt and endemic disease in South America, Europe and China. Traditional molecular epidemiologic typing suggested that a majority of current W cc11 burden represented global spread of the Hajj clone. However, recent whole genome sequencing (WGS) analyses revealed significant genetic heterogeneity among global W cc11 strains. While continued spread of the Hajj clone occurs in the Middle East, the meningitis belt and South Africa have co-circulation of the Hajj clone and other unrelated W cc11 strains. Notably, South America, the UK, and France share a genetically distinct W cc11 strain. Other W lineages persist in low numbers in Europe, North America and the meningitis belt. In summary, WGS is helping to unravel the complex genomic epidemiology of group W meningococcal strains. Wider application of WGS and strengthening of global IMD surveillance is necessary to monitor the continued evolution of group W lineages. [ABSTRACT FROM AUTHOR]

The epidemiology of invasive meningococcal disease continues to change rapidly, even in the three years since the first Meningococcal Exchange Meeting in 2008. Control of disease caused by serogroup C has been achieved in countries that have implemented meningococcal C or quadrivalent meningococcal ACWY conjugate vaccines. Initiation of mass immunization programs with meningococcal A conjugate vaccines across the meningitis belt of Africa may lead to the interruption of cyclical meningococcal epidemics. A meningococcal B vaccination program in New Zealand has led to a decreased incidence of high rates of endemic serogroup B disease. Increases in serogroup Y disease have been observed in certain Nordic countries which, if they persist, may require consideration of use of a multiple serogroup vaccine. The imminent availability of recombinant broadly protective serogroup B vaccines may provide the tools for further control of invasive meningococcal disease in areas where serogroup B disease predominates. Continued surveillance of meningococcal disease is essential; ongoing global efforts to improve the completeness of reporting are required. [ABSTRACT FROM AUTHOR]