29 research outputs found
Epidemiology, prevention and control of Legionnaires’ disease in Europe
Legionnaires’ disease (LD) is a water-borne infection cause by Gram-negative
bacteria Legionella spp. with virtually no person-to-person transmission. The
clinical presentation is a severe pneumonia with a case fatality of approximately
10%. Known risk factors include increasing age, chronic lung disease and various
conditions associated with immunodeficiency. Most cases are community-acquired
and sporadic. LD is notifiable in the European Union (EU) and European Economic
Area (EEA). LD incidence is thought to be increasing in Europe and the USA for
reasons not fully understood, including climate change, changing demographics
and improved surveillance. The overarching aim of this thesis was to explore various
aspects of LD epidemiology, prevention and control using surveillance data.
In study I, we retrieved travel-associated Legionnaire’s disease (TALD) surveillance
data for 2009 from the European Surveillance System, and tourism denominator
data from the Statistical Office of the European Union. We estimated the risk for
TALD in several European countries and highlighted potential under-ascertainment
of LD in some countries.
To confirm and generalize findings of studies performed at regional or national
level, we investigated the effect of temperature, rainfall, and atmospheric pressure
on short-term variations in LD notification rate in Denmark, Germany, Italy, and
the Netherlands in Study II. We fitted Poisson regression models to estimate the
association between meteorological variables and the weekly number of communityacquired
LD cases. We found that the higher risk was associated with simultaneous
increase in temperature and rainfall. These findings contributed to the growing
evidence supporting a possible impact of climate change on LD incidence.
In Study III, we investigate the actors associated with LD recurrence in hotels.
We conducted a retrospective cohort analysis and use survival analysis methods
to estimate the association between hotels characteristics and the occurrence of a
further case. We found that hotel size and previous association with multiple cases
were predictors of the occurrence of a further case. This study also highlighted
weaknesses in data collected in the surveillance scheme.
In Study IV, we used a large sample of LD over a 10-year period to look more
closely at healthcare-associated (HCA) LD. We found that HCA LD cases are
responsible for a major part of LD and differ from community-acquired cases in
many aspects, including demographics, causative strains and outcome.
Taken together, the findings support the use of surveillance data for research purposes.
They shed light on some epidemiological aspects of LD and inform the
surveillance system for possible improvements
Influenza epidemiology and immunization during pregnancy: Final report of a world health organization working group
From 2014 to 2017, the World Health Organization convened a working group to evaluate influenza disease burden and vaccine efficacy to inform estimates of maternal influenza immunization program impact. The group evaluated existing systematic reviews and relevant primary studies, and conducted four new systematic reviews. There was strong evidence that maternal influenza immunization prevented influenza illness in pregnant women and their infants, although data on severe illness prevention were lacking. The limited number of studies reporting influenza incidence in pregnant women and infants under six months had highly variable estimates and underrepresented low- and middle-income countries. The evidence that maternal influenza immunization reduces the risk of adverse birth outcomes was conflicting, and many observational studies were subject to substantial bias. The lack of scientific clarity regarding disease burden or magnitude of vaccine efficacy against severe illness poses challenges for robust estimation of the potential impact of maternal influenza immunization programs
Travel-associated hepatitis A in Europe, 2009 to 2015.
BackgroundTravel to countries with high or intermediate hepatitis A virus (HAV) endemicity is a risk factor for infection in residents of countries with low HAV endemicity. Aim: The objective of this study was to estimate the risk for hepatitis A among European travellers using surveillance and travel denominator data. Methods: We retrieved hepatitis A surveillance data from 13 European Union (EU)/ European Economic Area (EEA) countries with comprehensive surveillance systems and travel denominator data from the Statistical Office of the European Union. A travel-associated case of hepatitis A was defined as any case reported as imported. Results: From 2009 to 2015, the 13 countries reported 18,839 confirmed cases of hepatitis A, of which 5,233 (27.8%) were travel-associated. Of these, 39.8% were among children younger than 15 years. The overall risk associated with travel abroad decreased over the period at an annual rate of 3.7% (95% confidence interval (CI): 0.7-2.7) from 0.70 cases per million nights in 2009 to 0.51 in 2015. The highest risk was observed in travellers to Africa (2.11 cases per million nights). Cases more likely to be reported as travel-associated were male and of younger age (< 25 years). Conclusion: Travel is still a major risk factor for HAV infection in the EU/EEA, although the risk of infection may have slightly decreased in recent years. Children younger than 15 years accounted for a large proportion of cases and should be prioritised for vaccination
Pulmonary melioidosis in CAMBODIA: a prospective study
<p>Abstract</p> <p>Background</p> <p>Melioidosis is a disease caused by <it>Burkholderia pseudomallei </it>and considered endemic in South-East Asia but remains poorly documented in Cambodia. We report the first series of hospitalized pulmonary melioidosis cases identified in Cambodia describing clinical characteristics and outcomes.</p> <p>Methods</p> <p>We characterized cases of acute lower respiratory infections (ALRI) that were identified through surveillance in two provincial hospitals. Severity was defined by systolic blood pressure, cardiac frequency, respiratory rate, oxygen saturation and body temperature. <it>B. pseudomallei </it>was detected in sputum or blood cultures and confirmed by API20NE gallery. We followed up these cases between 6 months and 2 years after hospital discharge to assess the cost-of-illness and long-term outcome.</p> <p>Results</p> <p>During April 2007 - January 2010, 39 ALRI cases had melioidosis, of which three aged ≤2 years; the median age was 46 years and 56.4% were males. A close contact with soil and water was identified in 30 patients (76.9%). Pneumonia was the main radiological feature (82.3%). Eleven patients were severe cases. Twenty-four (61.5%) patients died including 13 who died within 61 days after discharge. Of the deceased, 23 did not receive any antibiotics effective against <it>B. pseudomallei</it>. Effective drugs that were available did not include ceftazidime. Mean total illness-related costs was of US25-$5000). Almost two-thirds (61.5%) incurred debt and 28.2% sold land or other belongings to pay illness-related costs.</p> <p>Conclusions</p> <p>The observed high fatality rate is likely explained by the lack or limited access to efficient antibiotics and under-recognition of the disease among clinicians, which led to inappropriate therapy.</p
Influenza surveillance in Europe: comparing intensity levels calculated using the moving epidemic method.
Although influenza-like illnesses (ILI) and acute respiratory illnesses (ARI) surveillance are well established in Europe, the comparability of intensity among countries and seasons remains an unresolved challenge. The objective is to compare the intensity of ILI and ARI in some European countries.
Weekly ILI and ARI incidence rates and proportion of primary care consultations were modeled in 28 countries for the 1996/1997-2013/2014 seasons using the moving epidemic method (MEM). We calculated the epidemic threshold and three intensity thresholds, which delimit five intensity levels: baseline, low, medium, high, and very high. The intensity of 2013/2014 season is described and compared by country.
The lowest ILI epidemic thresholds appeared in Sweden and Estonia (below 10 cases per 100 000) and the highest in Belgium, Denmark, Hungary, Poland, Serbia, and Slovakia (above 100 per 100 000). The 2009/2010 season was the most intense, with 35% of the countries showing high or very high intensity levels. The European epidemic period in season 2013/2014 started in January 2014 in Spain, Poland, and Greece. The intensity was between low and medium and only Greece reached the high intensity level, in weeks 7 to 9/2014. Some countries remained at the baseline level throughout the entire surveillance period.
Epidemic and intensity thresholds varied by country. Influenza-like illnesses and ARI levels normalized by MEM in 2013/2014 showed that the intensity of the season in Europe was between low and medium in most of the countries. Comparing intensity among seasons or countries is essential for understanding patterns in seasonal epidemics. An automated standardized model for comparison should be implemented at national and international levels.This work has been funded by the National and International Public Institutions and the Regional Health Department of Castilla y León (Spain).S
Initial assessment of the COVID-19 vaccination's impact on case numbers, hospitalisations and deaths in people aged 80 years and older, 15 EU/EEA countries, December 2020 to May 2021
Prioritisation of elderly people in COVID-19 vaccination campaigns aimed at reducing severe outcomes in this group. Using EU/EEA surveillance and vaccination uptake, we estimated the risk ratio of case, hospitalisation and death notifications in people 80 years and older compared with 25-59-year-olds. Highest impact was observed for full vaccination uptake 80% or higher with reductions in notification rates of cases up to 65% (IRR: 0.35; 95% CI: 0.13-0.99), hospitalisations up to 78% (IRR: 0.22; 95% CI: 0.13-0.37) and deaths up to 84% (IRR: 0.16; 95% CI: 0.13-0.20).S
Cost and disease burden of Dengue in Cambodia
<p>Abstract</p> <p>Background</p> <p>Dengue is endemic in Cambodia (pop. estimates 14.4 million), a country with poor health and economic indicators. Disease burden estimates help decision makers in setting priorities. Using recent estimates of dengue incidence in Cambodia, we estimated the cost of dengue and its burden using disability adjusted life years (DALYs).</p> <p>Methods</p> <p>Recent population-based cohort data were used to calculate direct and productive costs, and DALYs. Health seeking behaviors were taken into account in cost estimates. Specific age group incidence estimates were used in DALYs calculation.</p> <p>Results</p> <p>The mean cost per dengue case varied from US75 over 2006-2008 respectively, resulting in an overall annual cost from US14,429,513 during a large epidemic in 2007. Patients sustain the highest share of costs by paying an average of 78% of total costs and 63% of direct medical costs. DALY rates per 100,000 individuals ranged from 24.3 to 100.6 in 2007-2008 with 80% on average due to premature mortality.</p> <p>Conclusion</p> <p>Our analysis confirmed the high societal and individual family burden of dengue. Total costs represented between 0.03 and 0.17% of Gross Domestic Product. Health seeking behavior has a major impact on costs. The more accurate estimate used in this study will better allow decision makers to account for dengue costs particularly among the poor when balancing the benefits of introducing a potentially effective dengue vaccine.</p
Klebsiella pneumoniae related community-acquired acute lower respiratory infections in CAMBODIA: clinical characteristics and treatment
<p>Abstract</p> <p>Background</p> <p>In many Asian countries, <it>Klebsiella pneumoniae </it>(KP) is the second pathogen responsible for community-acquired pneumonia. Yet, very little is known about <it>KP </it>etiology in ALRI in Cambodia, a country that has one of the weakest medical infrastructures in the region. We present here the first clinico-radiological description of <it>KP </it>community-acquired ALRI in hospitalized Cambodian patients.</p> <p>Methods</p> <p>Through ALRI surveillance in two provincial hospitals, <it>KP </it>was isolated from sputum and blood cultures, and identified by API20E gallery from patients ≥ 5 years-old with fever and respiratory symptoms onset ≤14 days. Antibiotics susceptibility testing was provided systematically to clinicians when bacteria were isolated. We collected patients' clinical, radiological and microbiological data and their outcome 3 months after discharge. We also compared <it>KP</it>-related with other bacteria-related ALRI to determine risk factors for <it>KP </it>infection.</p> <p>Results</p> <p>From April 2007 to December 2009, 2315 ALRI patients ≥ 5 years-old were enrolled including 587 whose bacterial etiology could be assigned. Of these, 47 (8.0%) had <it>KP </it>infection; their median age was 55 years and 68.1% were females. Reported prior medication was high (42.5%). Patients' chest radiographs showed pneumonia (61.3% including 39% that were necrotizing), preexisting parenchyma lesions (29.5%) and pleural effusions alone (4.5%) and normal parenchyma (4.5%). Five patients had severe conditions on admission and one patient died during hospitalization. Of the 39 patients that were hospital discharged, 14 died including 12 within 1 month after discharge. Only 13 patients (28%) received an appropriate antibiotherapy. Extended-spectrum beta-lactamases (ESBL) - producing strains were found in 8 (17.0%) patients. Female gender (Odds ratio (OR) 2.1; <it>p </it>= 0.04) and diabetes mellitus (OR 3.1; <it>p </it>= 0.03) were independent risk factors for <it>KP</it>-related ALRI.</p> <p>Conclusions</p> <p><it>KP </it>ALRI in Cambodia has high fatality rate, are more frequently found in women, and should be considered in diabetic patients. The extremely high frequency of ESBL-producing strains in the study is alarming in the context of uncontrolled antibiotic consumption and in absence of microbiology capacity in most public-sector hospitals.</p
Influenza epidemiology and immunization during pregnancy: Final report of a World Health Organization working group
From 2014 to 2017, the World Health Organization convened a working group to evaluate influenza disease burden and vaccine efficacy to inform estimates of maternal influenza immunization program impact. The group evaluated existing systematic reviews and relevant primary studies, and conducted four new systematic reviews. There was strong evidence that maternal influenza immunization prevented influenza illness in pregnant women and their infants, although data on severe illness prevention were lacking. The limited number of studies reporting influenza incidence in pregnant women and infants under six months had highly variable estimates and underrepresented low- and middle-income countries. The evidence that maternal influenza immunization reduces the risk of adverse birth outcomes was conflicting, and many observational studies were subject to substantial bias. The lack of scientific clarity regarding disease burden or magnitude of vaccine efficacy against severe illness poses challenges for robust estimation of the potential impact of maternal influenza immunization programs