The prevention and control of infectious diseases involves dealing with numerous pathogens, each of which poses a specific threat to public health. In order to rationally allocate the limited ...resources for research, surveillance and other activities, it is necessary to prioritize infectious diseases; how to do this is the dilemma that public-health experts face.
Summary Background The quantification of the burden of disease attributable to hepatitis B virus (HBV) infection and the adaptation of prevention and control measures requires knowledge on its ...prevalence in the general population. For most countries such data are not routinely available. We estimated the national, regional, and global prevalence of chronic HBV infection. Methods For this systematic review and pooled analysis, we searched for data on prevalence of chronic HBV infection published between Jan 1, 1965, and Oct 23, 2013, in the databases Medline, Embase, CAB Abstracts (Global health), Popline, and Web of Science. We included studies reporting the hepatitis B surface antigen (HBsAg) serological marker of chronic HBV infection in non-high-risk groups and extracted data into a customised database. For each country, we calculated HBsAg prevalence estimates and 95% CIs weighted by study size. We extrapolated prevalence estimates to population sizes in 2010 to obtain the number of individuals with chronic HBV infection. Findings Of the 17 029 records screened, 1800 report on the prevalence of HBsAg covering 161 countries were included. HBsAg seroprevalence was 3·61% (95% CI 3·61–3·61) worldwide with highest endemicity in countries of the African region (total 8·83%, 8·82–8·83) and Western Pacific region (total 5·26%, 5·26–5·26). Within WHO regions, prevalence ranged from 0·20% (0·19–0·21; Mexico) to 13·55% (9·00–19·89; Haiti) in the Americas, to 0·48% (0·12–1·90; the Seychelles) to 22·38% (20·10–24·83; South Sudan) in the African region. We estimated that in 2010, globally, about 248 million individuals were HBsAg positive. Interpretation This first global assessment of country-level population prevalence of chronic HBV infection found a wide variation between countries and highlights the need for continued prevention and control strategies and the collection of reliable epidemiologic data using standardised methodology. Funding World Health Organization.
Group B streptococcus (GBS) is a leading cause of morbidity and mortality in newborns worldwide. From 2000 to 2008, national guidelines in Germany recommended intrapartum antibiotic prophylaxis for ...pregnant women displaying risk factors (eg, perinatal anogenital GBS colonization, rupture of the membranes ≥18 hours before birth) for the vertical transmission of GBS to their children. In 2008, these guidelines were revised to advocate universal, culture-based screening for GBS colonization among all pregnant women between 35 and 37 weeks of gestation. For the period 2009–2010, our prospective active surveillance study assessed the incidence of invasive GBS infections in infants 0–90 days of age in Germany. We did this by means of a capture–recapture analysis of 2 separate, independent systems (pediatric reporting versus laboratory reporting). We compared our results with those from a previous study by employing an equivalent design (2001–2003). We detected a 32% reduction in GBS incidence, from 0.47 per 1000 live births (n = 679) in 2001–2003 to 0.34 per 1000 live births (n = 450) in 2009–2010. This decline primarily is tied to a reduced number of GBS cases in children under 1 week of age. In 2009–2010, the ratio of early-onset disease to late-onset disease reversed from 1.52 (206:136), as determined in 2001–2003, to 0.75 (92:122). This study is the first to assess changes in the incidence of invasive GBS in Germany after the implementation of the guidelines for intrapartum prophylaxis for pregnant women colonized with GBS.
To examine the impact of hepatitis B vaccination schedules and types of vaccines on hepatitis B vaccination timing.
We used data for 211 643 children from demographic and health surveys in 47 low- ...and middle-income countries (median study year 2012). Data were from vaccination cards and maternal interviews. We grouped countries according to the vaccination schedule and type of vaccine used (monovalent or combination). For each country, we calculated hepatitis B vaccination coverage and timely receipt of vaccine doses. We used multivariable logistic regression models to study the effect of vaccination schedules and types on vaccination delay.
Substantial delays in vaccination were observed even in countries with fairly high coverage of all doses. Median delay was 1.0 week (interquartile range, IQR: 0.3 to 3.6) for the first dose (
= 108 626 children) and 3.7 weeks (IQR: 1.4 to 9.3) for the third dose (
= 101 542). We observed a tendency of lower odds of delays in vaccination schedules starting at 6 and at 9 weeks of age. For the first vaccine dose, we recorded lower odds of delays for combination vaccines than for monovalent vaccines (adjusted odds ratio, aOR: 0.76, 95% confidence interval, CI: 0.71 to 0.81).
Wide variations in hepatitis B vaccination coverage and adherence to vaccination schedules across countries underscore the continued need to strengthen national immunization systems. Timely initiation of the vaccination process might lead to timely receipt of successive doses and improved overall coverage. We suggest incorporating vaccination timing as a performance indicator of vaccination programmes to complement coverage metrics.
Previous controlled studies on the effect of non-pharmaceutical interventions (NPI) - namely the use of facemasks and intensified hand hygiene - in preventing household transmission of influenza have ...not produced definitive results. We aimed to investigate efficacy, acceptability, and tolerability of NPI in households with influenza index patients.
We conducted a cluster randomized controlled trial during the pandemic season 2009/10 and the ensuing influenza season 2010/11. We included households with an influenza positive index case in the absence of further respiratory illness within the preceding 14 days. Study arms were wearing a facemask and practicing intensified hand hygiene (MH group), wearing facemasks only (M group) and none of the two (control group). Main outcome measure was laboratory confirmed influenza infection in a household contact. We used daily questionnaires to examine adherence and tolerability of the interventions.
We recruited 84 households (30 control, 26 M and 28 MH households) with 82, 69 and 67 household contacts, respectively. In 2009/10 all 41 index cases had a influenza A (H1N1) pdm09 infection, in 2010/11 24 had an A (H1N1) pdm09 and 20 had a B infection. The total secondary attack rate was 16% (35/218). In intention-to-treat analysis there was no statistically significant effect of the M and MH interventions on secondary infections. When analysing only households where intervention was implemented within 36 h after symptom onset of the index case, secondary infection in the pooled M and MH groups was significantly lower compared to the control group (adjusted odds ratio 0.16, 95% CI, 0.03-0.92). In a per-protocol analysis odds ratios were significantly reduced among participants of the M group (adjusted odds ratio, 0.30, 95% CI, 0.10-0.94). With the exception of MH index cases in 2010/11 adherence was good for adults and children, contacts and index cases.
Results suggest that household transmission of influenza can be reduced by the use of NPI, such as facemasks and intensified hand hygiene, when implemented early and used diligently. Concerns about acceptability and tolerability of the interventions should not be a reason against their recommendation.
The study was registered with ClinicalTrials.gov (Identifier NCT00833885).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
For neonates, group B Streptococcus is life threatening. Current prevention strategies remain insufficient, especially for cases of late-onset sepsis, where intrapartum antibiotic prophylaxis has ...demonstrated no benefit. One promising approach is the vaccination of pregnant women, which offers protective immunity via transplacental transmission of neutralizing antibodies. Our nationwide, prospective surveillance study aimed to characterize the prevalence of pilus antigen, capsular polysaccharide serotypes, and antibiotic resistance from invasive GBS infections in neonates and compare these results with those from children and adults in Germany. Our study includes 173 neonatal isolates of a total of 450 reported cases during the study period (incidence0.34/1000 live births), in addition to 2 pediatric and 803 adult isolates. The comparison between neonatal and adult isolates reveals age-dependent differences in capsular serotype and pilus type distribution and differences in antibiotic resistance patterns.
•A new diagnostic tool to distinguish vaccinated from infected immune response for HAV.•Clinical validation of HAV multiplex serology.•High sensitivity, specificity and accuracy to measure HAV ...infection and vaccination.•Using Luminex® technology to facilitate sero-epidemiological studies.
Worldwide about 1.5 million clinical cases of hepatitis A virus (HAV) infections occur every year and increasingly countries are introducing HAV vaccination into the childhood immunization schedule with a single dose instead of the originally licenced two dose regimen. Diagnosis of acute HAV infection is determined serologically by anti-HAV-IgM detection using ELISA. Additionally anti-HAV-IgG can become positive during the early phase of symptoms, but remains detectable after infection and also after vaccination against HAV. Currently no serological marker allows the differentiation of HAV vaccinated individuals and those with a past infection with HAV. Such differentiation would greatly improve evaluation of vaccination campaigns and risk assessment of HAV outbreaks. Here we tested the HAV non-structural protein 2A, important for the capsid assembly, as a biomarker for the differentiation of the immune status in previously infected and vaccinated individuals.
HAV antigens were recombinantly expressed as glutathione-S-transferase (GST) fusion proteins. Using glutathione tagged, magnetic fluorescent beads (Luminex®), the proteins were affinity purified and used in a multiplex serological assay. The multiplex HAV assay was validated using 381 reference sera in which the immune status HAV negative, vaccinated or infected was established using the Abbott ARCHITECT® HAVAb-IgM or IgG, the commercial HAV ELISA from Abnova and documentation in vaccination cards.
HAV multiplex serology showed a sensitivity of 99% and specificity of 95% to detect anti-HAV IgG/IgM positive individuals. HAV biomarker 2A allowed the differentiation between previously infected and vaccinated individuals. HAV vaccinated individuals and previously infected individuals could be identified with 92% accuracy.
HAV biomarker 2A can be used to differentiate between previously HAV-vaccinated and naturally infected individuals. Within a multiplex serological approach this assay can provide valuable novel information in the context of outbreak investigations, longitudinal population based studies and evaluations of immunization campaigns.
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