General practitioner practices in requesting laboratory tests for patients with gastroenteritis in the Netherlands, 2001–2002

BACKGROUND: The objective of this study was to estimate the (selective) proportion of patients consulting their GP for an episode of gastroenteritis for whom laboratory tests were requested. In addition adherence of GPs to the guidelines for diagnostic test regime was ascertained. METHODS: Data were collected from a GP network in the Netherlands. Information was also collected on the reason for requesting the test, test specifications, and test results. RESULTS: For 12% of the GP patients with gastroenteritis, a stool sample was requested and tested for enteric pathogens. In most patients, the duration, followed by severity of complaints or a visit to a specific, high-risk country were reported as reasons to request laboratory diagnostics. Tests were requested most often in summer months and in February. Campylobacter (requested for 87% of the tests), Salmonella (84%), Shigella (78%) and Yersinia (56%) were most frequently included in the stool tests. Campylobacter was detected most often in patients. CONCLUSION: Test requests did not always comply with existing knowledge of the etiology of gastroenteritis in GP patients and were not always consistent with the Dutch GP guidelines. Therefore, the data of this study can be used to develop educational approaches for GP's as well as for revision of the guidelines

The burden of varicella from a parent's perspective and its societal impact in The Netherlands: an Internet survey

<p>Abstract</p> <p>Background</p> <p>Varicella is a common childhood disease. Only 5% of first varicella-zoster-virus infections occur asymptomatically. Most data on the burden of varicella stem from health service databases. This study aims to provide insight in the burden of varicella from a parent's perspective including cases outside the healthcare system.</p> <p>Methods</p> <p>An internet questionnaire was developed for parents in the Netherlands to report health care resource use and productivity losses during the varicella episode in their child younger than 6 years. 11,367 invitations were sent out to members with children of an internet panel of a market research agency. 4,168 (37%) parents started the questionnaire (response rate), of which 360 (9%) stopped before completion and 1,838 (44%) were out of the target group. In total 1,970 parents completed the questionnaire. The questionnaire provided a symptom list ranging from common symptoms, such as skin vesicles, itching to fits or convulsions. A posteriori, in the analyses, the symptoms 'skin infections', 'fits/convulsions', 'unconsciousness', and 'balance and movement disorders' were labelled as complications. There was no restriction to time since the varicella episode for inclusion in the analyses.</p> <p>Results</p> <p>The 1,970 respondents had in total 2,899 children aged younger than six years, of which 2,564 (88%) children had had varicella. In 62% of the episodes the parent did not seek medical help. In 18% of all episodes symptoms labelled as complications were reported; in 11% of all episodes parents visited a medical doctor (MD) for a complication. Reporting of complications did not differ (X²; p = 0.964) between children with a recent (≤ 12 months ago) or a more distant (> 12 months) history of varicella. Prescription drugs were used in 12% of the children with varicella; OTC drugs in 72%. Parents reported work loss in 17% of the varicella-episodes (23% when MD visit; 14% when no MD-visit) for on average 14 hours, which equals to 2.5 hours of work loss for any given varicella-episode.</p> <p>Conclusions</p> <p>This study shows the full spectrum of varicella-episodes and associated healthcare use, including the large proportion of cases not seeking medical care and the societal impact associated with those cases.</p

Comparing Pandemic to Seasonal Influenza Mortality: Moderate Impact Overall but High Mortality in Young Children

Background: We assessed the severity of the 2009 influenza pandemic by comparing pandemic mortality to seasonal influenza mortality. However, reported pandemic deaths were laboratory-confirmed - and thus an underestimation - whereas seasonal influenza mortality is often more inclusively estimated. For a valid comparison, our study used the same statistical methodology and data types to estimate pandemic and seasonal influenza mortality. Methods and Findings: We used data on all-cause mortality (1999-2010, 100% coverage, 16.5 million Dutch population) and influenza-like-illness (ILI) incidence (0.8% coverage). Data was aggregated by week and age category. Using generalized estimating equation regression models, we attributed mortality to influenza by associating mortality with ILI-incidence, while adjusting for annual shifts in association. We also adjusted for respiratory syncytial virus, hot/cold weather, other seasonal factors and autocorrelation. For the 2009 pandemic season, we estimated 612 (range 266-958) influenza-attributed deaths; for seasonal influen

Incidence and risk factors for community-acquired acute gastroenteritis in north-west Germany in 2004

In developed countries, acute gastroenteritis (AGE) is a major source of morbidity. However, only a few studies have estimated its incidence and the associated medical burden. This population-based study determined the incidence of community-acquired AGE patients seeking medical care and the relative role of various pathogens. Stool samples from patients with AGE presenting to a general practitioner (GP), pediatrician, or specialist in internal medicine for that reason were screened for various bacterial and viral enteropathogens. A control group was established as well. Incidences were calculated by the number of positive patients divided by the general population. The study was performed in north-west Germany in 2004. The incidence of AGE patients requiring medical consultation was 4,020/100,000 inhabitants. Children (<5 years of age) were at the highest risk (13,810/100,000 inhabitants). Of the patients, 6.6% were tested positive for an enteropathogenic bacteria and 17.7% for a viral agent. The predominant pathogens were norovirus (626/100,000) and rotavirus (270/100,000). Salmonella was the most frequently detected bacteria (162/100,000). The results presented confirm AGE and, specifically, AGE of viral origin as a major public health burden in developed countries

Population distribution and burden of acute gastrointestinal illness in British Columbia, Canada

BACKGROUND: In developed countries, gastrointestinal illness (GI) is typically mild and self-limiting, however, it has considerable economic impact due to high morbidity. METHODS: The magnitude and distribution of acute GI in British Columbia (BC), Canada was evaluated via a cross-sectional telephone survey of 4,612 randomly selected residents, conducted from June 2002 to June 2003. Respondents were asked if they had experienced vomiting or diarrhoea in the 28 days prior to the interview. RESULTS: A response rate of 44.3% was achieved. A monthly prevalence of 9.2% (95%CI 8.4 – 10.0), an incidence rate of 1.3 (95% CI 1.1–1.4) episodes of acute GI per person-year, and an average probability that an individual developed illness in the year of 71.6% (95% CI 68.0–74.8), weighted by population size were observed. The average duration of illness was 3.7 days, translating into 19.2 million days annually of acute GI in BC. CONCLUSION: The results corroborate those from previous Canadian and international studies, highlighting the substantial burden of acute GI

Measuring underreporting and under-ascertainment in infectious disease datasets: a comparison of methods

Gibbons CL, Mangen M-JJ, Plaß D, et al. Measuring underreporting and under-ascertainment in infectious disease datasets: a comparison of methods. BMC Public Health. 2014;14(1): 147.Background: Efficient and reliable surveillance and notification systems are vital for monitoring public health and disease outbreaks. However, most surveillance and notification systems are affected by a degree of underestimation (UE) and therefore uncertainty surrounds the 'true' incidence of disease affecting morbidity and mortality rates. Surveillance systems fail to capture cases at two distinct levels of the surveillance pyramid: from the community since not all cases seek healthcare (under-ascertainment), and at the healthcare-level, representing a failure to adequately report symptomatic cases that have sought medical advice (underreporting). There are several methods to estimate the extent of under-ascertainment and underreporting. Methods: Within the context of the ECDC-funded Burden of Communicable Diseases in Europe (BCoDE)-project, an extensive literature review was conducted to identify studies that estimate ascertainment or reporting rates for salmonellosis and campylobacteriosis in European Union Member States (MS) plus European Free Trade Area (EFTA) countries Iceland, Norway and Switzerland and four other OECD countries (USA, Canada, Australia and Japan). Multiplication factors (MFs), a measure of the magnitude of underestimation, were taken directly from the literature or derived (where the proportion of underestimated, under-ascertained, or underreported cases was known) and compared for the two pathogens. Results: MFs varied between and within diseases and countries, representing a need to carefully select the most appropriate MFs and methods for calculating them. The most appropriate MFs are often disease-,country-, age-, and sex-specific. Conclusions: When routine data are used to make decisions on resource allocation or to estimate epidemiological parameters in populations, it becomes important to understand when, where and to what extent these data represent the true picture of disease, and in some instances (such as priority setting) it is necessary to adjust for underestimation. MFs can be used to adjust notification and surveillance data to provide more realistic estimates of incidence

ARI-EL: a case-control study on acute respiratory infections in general practitioner patients. Interim report of Oct. 2000 through Sept. 2001

From October 2000 the Dutch influenza surveillance is temporarily expanded to a case-control study on acute respiratory infections (ARI) in general practitioner (GP) patients: the ARI-EL study. The aim is gaining insight into 1) the incidence and aetiology of ARI, 2) risk factors for contracting ARI and 3) health-care demand and burden of illness due to ARI. GPs from the Netherlands Institute for Health Services Research (NIVEL) register all patients consulting them for ARI. Weekly, GPs sample one case, defined as one of the patients consulting them with complaints of ARI, and one control, defined as a patient consulting them without complaints of ARI. The samples are analysed at the National Institute of Public Health and the Environment (RIVM) in Bilthoven for respiratory viruses by culture and PCR, and for respiratory bacteria by culture at the Regional Laboratory of Public Health in Tilburg. Participating patients filled in a questionnaire at home. The background and methods of the ARI-EL study are presented in this interim report, along with some of the preliminary results of the first study year. In the controls, statistically significant fewer viruses were detected; in 53% of samples of the cases viruses were detected, compared to 19% of the samples from the controls. Influenza virus and rhinovirus were detected significantly more often in the cases than in the controls. Bacteria were detected in the same measure in the cases and controls. Only beta-haemolytic streptococci group A were significantly more often detected in the cases. In 31% of the cases and in 67% of the controls no micro-organisms other than the commensal flora were detected. The study has been found to be feasible, despite the burden for the GPs. It will continue until at least September 2002 to enable us to collect sufficient data for statistical analyses, and consequently to summon sufficient power to draw conclusions. The loss of data by applying the precise case and control definitions plus the fact that winter 2000/2001 was an extremely calm influenza season emphasise the need for data collection during a sufficiently long period. Then this exceptional study will provide information on the yearly and seasonal incidence of ARI and associated pathogens, the burden of illness, the health-care demand and the risk factors for contracting ARI.Vanaf oktober 2000 is de Nederlandse influenza-surveillance tijdelijk uitgebreid tot een case-controle studie naar acute respiratoire infecties (ARI) bij huisartspatienten: de ARI-EL studie. Doel is inzicht verkrijgen in de incidentie en etiologie van ARI, risicofactoren voor ARI en in de zorgvraag en ziektelast tengevolge van ARI. Huisartsen van het Nederlands Instituut voor Onderzoek van de Gezondheidszorg (NIVEL) registreren wekelijks het aantal consulten voor ARI en bemonsteren maximaal een case en een controle per week. De monsters worden onderzocht op respiratoire pathogenen op het Rijksinstituut voor de Volksgezondheid en Milieu (RIVM) en op het Streeklaboratorium voor de Volksgezondheid Tilburg met kweek en PCR. De deelnemende patienten vullen thuis een vragenlijst in. Bij cases werd significant vaker een virus aangetoond (bij 53 % van de cases versus 19% van de controles). Influenzavirus en rhinovirus werden significant vaker aangetoond in cases. Het percentage van de monsters waarin een bacterie werd aangetoond verschilde niet significant tussen cases en controles. Alleen beta-haemolytische streptokokken groep A werden significant vaker aangetoond bij cases. Bij 31% van de cases en bij 67% van de controles werd geen ziekteverwekker aangetoond Het blijkt dat de studie haalbaar is, maar wel redelijk belastend voor de huisartsen. De ARI-EL studie loopt door tot en met minimaal september 2002. Dit is nodig om voldoende gegevens te verzamelen voor statistische analyse met voldoende power om conclusies te kunnen trekken. Het verlies van gegevens door strikte toepassing van de case- en controledefinities en het feit dat winter 2000/2001 een uitzonderlijk rustig influenzaseizoen is geweest, benadrukken het belang van voldoende lange gegevensverzameling. Dan zal deze unieke studie informatie opleveren over de jaar- en seizoensincidentie van ARI en daarmee samenhangende pathogenen, ziektelast, zorgvraag en determinanten bij huisartspatienten

ARI-EL: a case-control study on acute respiratory infections in general practitioner patients. Interim report of Oct. 2000 through Sept. 2001

Vanaf oktober 2000 is de Nederlandse influenza-surveillance tijdelijk uitgebreid tot een case-controle studie naar acute respiratoire infecties (ARI) bij huisartspatienten: de ARI-EL studie. Doel is inzicht verkrijgen in de incidentie en etiologie van ARI, risicofactoren voor ARI en in de zorgvraag en ziektelast tengevolge van ARI. Huisartsen van het Nederlands Instituut voor Onderzoek van de Gezondheidszorg (NIVEL) registreren wekelijks het aantal consulten voor ARI en bemonsteren maximaal een case en een controle per week. De monsters worden onderzocht op respiratoire pathogenen op het Rijksinstituut voor de Volksgezondheid en Milieu (RIVM) en op het Streeklaboratorium voor de Volksgezondheid Tilburg met kweek en PCR. De deelnemende patienten vullen thuis een vragenlijst in. Bij cases werd significant vaker een virus aangetoond (bij 53 % van de cases versus 19% van de controles). Influenzavirus en rhinovirus werden significant vaker aangetoond in cases. Het percentage van de monsters waarin een bacterie werd aangetoond verschilde niet significant tussen cases en controles. Alleen beta-haemolytische streptokokken groep A werden significant vaker aangetoond bij cases. Bij 31% van de cases en bij 67% van de controles werd geen ziekteverwekker aangetoond Het blijkt dat de studie haalbaar is, maar wel redelijk belastend voor de huisartsen. De ARI-EL studie loopt door tot en met minimaal september 2002. Dit is nodig om voldoende gegevens te verzamelen voor statistische analyse met voldoende power om conclusies te kunnen trekken. Het verlies van gegevens door strikte toepassing van de case- en controledefinities en het feit dat winter 2000/2001 een uitzonderlijk rustig influenzaseizoen is geweest, benadrukken het belang van voldoende lange gegevensverzameling. Dan zal deze unieke studie informatie opleveren over de jaar- en seizoensincidentie van ARI en daarmee samenhangende pathogenen, ziektelast, zorgvraag en determinanten bij huisartspatienten.From October 2000 the Dutch influenza surveillance is temporarily expanded to a case-control study on acute respiratory infections (ARI) in general practitioner (GP) patients: the ARI-EL study. The aim is gaining insight into 1) the incidence and aetiology of ARI, 2) risk factors for contracting ARI and 3) health-care demand and burden of illness due to ARI. GPs from the Netherlands Institute for Health Services Research (NIVEL) register all patients consulting them for ARI. Weekly, GPs sample one case, defined as one of the patients consulting them with complaints of ARI, and one control, defined as a patient consulting them without complaints of ARI. The samples are analysed at the National Institute of Public Health and the Environment (RIVM) in Bilthoven for respiratory viruses by culture and PCR, and for respiratory bacteria by culture at the Regional Laboratory of Public Health in Tilburg. Participating patients filled in a questionnaire at home. The background and methods of the ARI-EL study are presented in this interim report, along with some of the preliminary results of the first study year. In the controls, statistically significant fewer viruses were detected; in 53% of samples of the cases viruses were detected, compared to 19% of the samples from the controls. Influenza virus and rhinovirus were detected significantly more often in the cases than in the controls. Bacteria were detected in the same measure in the cases and controls. Only beta-haemolytic streptococci group A were significantly more often detected in the cases. In 31% of the cases and in 67% of the controls no micro-organisms other than the commensal flora were detected. The study has been found to be feasible, despite the burden for the GPs. It will continue until at least September 2002 to enable us to collect sufficient data for statistical analyses, and consequently to summon sufficient power to draw conclusions. The loss of data by applying the precise case and control definitions plus the fact that winter 2000/2001 was an extremely calm influenza season emphasise the need for data collection during a sufficiently long period. Then this exceptional study will provide information on the yearly and seasonal incidence of ARI and associated pathogens, the burden of illness, the health-care demand and the risk factors for contracting ARI.IGZGZ