Risk of pneumonia in the vicinity of goat farms: a comparative assessment of temporal variation based on longitudinal health data.

BACKGROUND: Although the association between living in the vicinity of a goat farm and the occurrence of pneumonia is well-documented, it is unclear whether the higher risk of pneumonia in livestock dense areas is season-specific or not. This study explored the temporal variation of the association between exposure to goat farms and the occurrence of pneumonia. METHODS: A large population-based study was conducted in the Netherlands, based on electronic health records from 49 general practices, collected for a period of six consecutive years (2014-2019). Monthly incidence rates of pneumonia in a livestock dense area were compared with those of a control group (areas with low livestock density) both per individual year and cumulatively for the entire six-year period. Using individual estimates of livestock exposure, it was also examined whether incidence of pneumonia differed per month if someone lived within a certain radius from a goat farm, compared to residents who lived further away. RESULTS: Pneumonia was consistently more common in the livestock dense area throughout the year, compared to the control area. Analyses on the association between the individual livestock exposure estimates and monthly pneumonia incidence for the whole six-year period, yielded a generally higher risk for pneumonia among people living within 500 m from a goat farm, compared to those living further away. Significant associations were observed for March (IRR 1.68, 95% CI 1.02-2.78), August (IRR 2.67, 95% CI 1.45-4.90) and September (IRR 2.52, 95% CI 1.47-4.32). CONCLUSIONS: The increased occurrence of pneumonia in the vicinity of goat farms is not season-specific. Instead, pneumonia is more common in livestock dense areas throughout the year, including summer months.

Increased risk of pneumonia amongst residents living near goat farms in different livestock-dense regions in the Netherlands.

BACKGROUND: Previous studies, performed between 2009-2019, in the Netherlands observed an until now still unexplained increased risk for pneumonia among residents living close to goat farms. Since data were collected in the provinces Noord-Brabant and Limburg (NB-L), an area with relatively high air pollution levels and proximity to large industrial areas in Europe, the question remains whether the results are generalizable to other regions. In this study, a different region, covering the provinces Utrecht, Gelderland, and Overijssel (UGO) with a similar density of goat farms, was included to assess whether the association between goat farm proximity and pneumonia is consistently observed across the Netherlands. METHODS: Data for this study were derived from the Electronic Health Records (EHR) of 21 rural general practices (GPs) in UGO, for 2014-2017. Multi-level analyses were used to compare annual pneumonia prevalence between UGO and data derived from rural reference practices ('control area'). Random-effects meta-analysis (per GP practice) and kernel analyses were performed to study associations of pneumonia with the distance between goat farms and patients' home addresses. RESULTS: GP diagnoses of pneumonia occurred 40% more often in UGO compared to the control area. Meta-analysis showed an association at a distance of less than 500m (~70% more pneumonia compared to >500m) and 1000m (~20% more pneumonia compared to >1000m). The kernel-analysis for three of the four individual years showed an increased risk up to a distance of one or two kilometers (2-36% more pneumonia; 10-50 avoidable cases per 100,000 inhabitants per year). CONCLUSIONS: The positive association between living in the proximity of goat farms and pneumonia in UGO is similar to the previously found association in NB-L. Therefore, we concluded that the observed associations are relevant for regions with goat farms in the entire country.

The impact of a terrorist attack: Survivors' health, functioning and need for support following the 2019 Utrecht tram shooting 6 and 18 months post-attack.

Background: Extremely violent events such as terrorist attacks and mass shootings form a severe risk for the health and wellbeing of affected individuals. In this study based on a public health monitor, we focus on the health impact (including PTSD symptoms, physical problems and day-to-day functioning) of the Utrecht tram shooting, which took place in the morning of March 18th 2019. A lone gunman opened fire on passengers within a moving tram. Four people died, and six people were injured in this attack. The attack resulted in nationwide commotion and drew much media attention. Aim of this study was to increase insight into the health effects for the survivors (those directly impacted by a terrorist attack and the bereaved), and whether they received the needed care and support. Methods: Semi-structured interviews with accompanying questionnaires were conducted at six and 18 months post-attack. Overall, 21 survivors (victims/witnesses and loved ones of deceased victims) participated in the first series of interviews, 15 in the second series. Qualitative data were analyzed using reflexive thematic analysis, quantitative data was only described because of the low sample size. Results: At both six and 18 months after the attack many survivors had been able to resume daily life, and most rated their overall health as (very) good or excellent. At the same time, a substantial portion suffered from health problems such as posttraumatic stress symptoms and other complaints, and needed professional care. Furthermore, those in need did not always find their own way to appropriate care through the existing health system: half of the survivors still needed support in finding the right care 18 months later. Conclusion: Although the design and implementation of this public health monitor were accompanied by multiple challenges, it was possible to track a portion of the survivors and gain insight in the considerable health burden of the attack. Also, it is clear in this study that the health impact of terrorism affects survivors in the long run and requires attention from health authorities and professionals, as survivors were not able to find the right care by themselves.

Human Health Risks of Conducted Electrical Weapon Exposure: A Systematic Review.

Importance: Conducted electrical weapons (CEWs) are used broadly as a less-lethal force option for police officers. However, there is no clear picture of the possible health risks in humans on the basis of rigorously assessed scientific evidence from the international peer-reviewed literature. Objective: To synthesize and systematically evaluate the strength of published evidence for an association between exposure to different models of CEWs and adverse acute as well as chronic conditions. Evidence Review: Following a preregistered review protocol, the literature search strategy was based on a search of reviews published between January 1, 2000, and April 24, 2020, of PubMed, MEDLINE, EMBASE, Web of Science, PsycINFO, and Cochrane Library, as well as relevant online databases and bibliographic sources, such as reference sections of recent publications. The identified studies were independently assessed in terms of scope, relevance, methodologic bias, and quality. Peer-reviewed publications of human studies were included, using original data and with a focus on the use of taser CEWs in the context of law enforcement. Eligible studies examined clearly defined health outcomes as dependent variables following exposure to a CEW. The review followed the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. A meta-analysis could not be conducted. Findings: Of the 1081 unique records screened, 33 relevant studies were identified, all of them of experimental design and conducted in the US. Eleven studies had a low risk of bias and 22 had a higher bias risk. Studies focused on outcomes such as physiologic stress responses, heart rate, blood pressure, arrhythmias, or cognitive performance. Independently of bias risk, the studies reported few or no acute health problems, apart from the wounds caused by the darts. Furthermore, no long-term outcomes were studied. Most of the studies were performed on healthy, physically fit individuals (eg, police officers) in a controlled setting, with short exposure duration (5 seconds). Half of the studies, mainly those with a higher risk of bias, were at least partly funded by the manufacturer. Conclusions and Relevance: Based on the findings of the reviewed studies, the risk for adverse health outcomes due to CEW exposure can be currently estimated as low. However, most of the reviewed studies had methodologic limitations. Considering that recruited participants were not representative of the population that usually encounters a CEW deployment, it is not possible to draw conclusions regarding exposure outcomes in potentially vulnerable populations or high-risk groups, such as those under the influence of substances.

Immediate and long-term health impact of exposure to gas-mining induced earthquakes and related environmental stressors.

BACKGROUND: Little is known about the public health impact of chronic exposure to physical and social stressors in the human environment. Objective of this study was to investigate the immediate and long-term health effects of living in an environment with gas-mining induced earthquakes and related stressors in the Netherlands. METHODS: Data on psychological, somatic and social problems recorded routinely in electronic health records by general practitioners during a 6-year period (2010-2015) were combined with socioeconomic status and seismicity data. To assess immediate health effects of exposure to ML≥1.5 earthquakes, relative risk ratios were calculated for patients in the week of an earthquake and the week afterwards, and compared to the week before the earthquake. To analyse long-term health effects, relative risks of different groups, adjusted for age, sex and socioeconomic status, were computed per year and compared. RESULTS: Apart from an increase in suicidality, few immediate health changes were found in an earthquake week or week afterwards. Generally, the prevalence of health problems was higher in the mining province in the first years, but dropped to levels equal to or even below the control group in subsequent years, with lower relative risks observed in more frequently exposed patients. CONCLUSIONS: From a public health perspective, the findings are fascinating. Contrary to our expectation, health problems presented in general practice in the earthquake province decreased during the study period. More frequently exposed populations reported fewer health issues to general practitioners, which might point at health adaptation to chronic exposure to stressors.

The experience of sudden loss of a colleague or neighbor following the MH17 plane crash in the Ukraine: a qualitative interview study.

BACKGROUND: The literature on loss and traumatic grief after disasters provides findings on the impact of losing a partner, child or close friend on partners, parents and friends. However, little attention has been given to the broader everyday social environment of deceased persons. The present study constitutes a qualitative exploration of the impact on colleagues and neighbors following the MH17 airplane disaster in the Ukraine, July 2014. METHODS: Eighteen structured interviews were conducted with eleven colleagues and seven neighbors. The interviews focused on the relation(-ship) with the victim, on the disaster, the first days and weeks hereafter, and the status one and a half years after the crash. RESULTS: Especially for colleagues and neighbors with an intensive, long-lasting relation and ties based on friendship and trust, the impact of the sudden death was large. The MH17 disaster was considered a special event, different from, for instance, an "ordinary" accident. It was actively covered by the media and a recurrent conversation topic in meetings with other people. In the workplace, employers and less involved colleagues show empathy for a limited period of time, but grief has an expiration date - a moment where it gets more difficult to others or influences productivity. The appreciation for rituals in the workplace or in the neighborhood varies. CONCLUSIONS: The interviews indicate a "hierarchy of bereavement". People are not part of the typical inner circle, but feel "affected" and experience little social recognition and acknowledgment, particularly in the longer term. As such, colleagues and neighbors may experience loneliness and/or isolation. Generally, there is no need to consult a practitioner, despite the experience of health complaints such as intrusive dreaming and lack of sleep.

Patients with overlapping diagnoses of asthma and COPD: is livestock exposure a risk factor for comorbidity and coexisting symptoms and infections?

BACKGROUND: Epidemiological research on health effects of livestock exposure in population subgroups with compromised respiratory health is still limited. The present study explored the association between livestock exposure and comorbid/concurrent conditions in patients with overlapping diagnoses of asthma and COPD. METHODS: Electronic health record data from 23 general practices in the Netherlands were collected from 425 patients diagnosed with both asthma and COPD, living in rural areas with high livestock density ("study area"). Data of 341 patients with the same overlapping diagnoses, living in rural areas with lower livestock density ("control areas") were obtained from 19 general practices. First, the prevalence of comorbid disorders and symptoms/infections were compared between the study and control area. Second, the examined health outcomes were analyzed in relation to measures of individual livestock exposure. RESULTS: Pneumonia was twice as common among patients living in areas with a high livestock density (OR 2.29, 99% CI 0.96-5.47); however, there were generally no statistically significant differences in the investigated outcomes between the study and control area. Significant associations were observed between presence of goats within 1000 m and allergic rhinitis (OR 5.71, 99% CI 1.11-29.3, p < 0.01), number of co-occurring symptoms (IRR 1.69, 99% CI 1.03-2.77, p < 0.01) and anxiety (OR 8.18, 99% 1.5-44.7, p < 0.01). Presence of cattle within 500 m was associated with pneumonia prevalence (OR 2.48, 99% CI 1.05-5.84, p < 0.01). CONCLUSION: Livestock exposure is not associated with comorbid chronic conditions but appears to be a risk factor for symptomatic effects in patients with overlapping diagnoses of asthma and COPD.

The organization of post-disaster psychosocial support in the Netherlands: a meta-synthesis.

Background: Despite numerous calls for a more evidence-based provision of post-disaster psychosocial support, systematic analyses of post-disaster service delivery are scarce. Objective: The aim of this review was to evaluate the organization of post-disaster psychosocial support in different disaster settings and to identify determinants. Methods: We conducted a meta-synthesis of scientific literature and evaluations of post-disaster psychosocial support after 12 Dutch disasters and major crises between 1992 and 2014. We applied systematic search and snowballing methods and included 80 evaluations, as well as grey and scientific documents. Results: Many documents focus on the prevalence of mental health problems. Only a few documents primarily assess the organization of post-disaster psychosocial support and its determinants. The material illustrates how, over the course of two decades, the organizational context of post-disaster psychosocial support in the Netherlands has been influenced by changes in legislation, policy frameworks, evidence-based guidelines, and the instalment of formal expertise structures to support national and local governments and public services. Recurring organizational issues in response to events are linked to interrelated evaluation themes such as planning, training, registration, provision of information and social acknowledgement. For each evaluation theme, we identify factors helping or hindering the psychosocial support organization during the preparedness, acute and recovery phases. Conclusions: The meta-synthesis illustrates that psychosocial service delivery has grown from a monodisciplinary to a multidisciplinary field over time. Suboptimal interprofessional collaboration poses a recurring threat to service quality. Despite the development of the knowledge base, post-disaster psychosocial support in the Netherlands lacks a systematic and critical appraisal of its functioning. Further professionalization is coupled with the strengthening of evaluation and learning routines.

Antecedentes: A pesar de las numerosas solicitudes de más prestaciones de apoyo psicosocial posterior al desastre basadas en evidencia, los análisis sistemáticos de éstas son escasos.Objetivo: Evaluar la organización del apoyo psicosocial posterior al desastre en diferentes entornos de desastre e identificar los determinantes.Métodos: Realizamos una meta-síntesis de la literatura científica y evaluaciones de apoyo psicosocial posterior al desastre después de 12 desastres holandeses y crisis mayores entre 1992 y 2014. Aplicamos métodos de búsqueda sistemática y de 'bola de nieve' e incluimos 80 evaluaciones, así como documentos científicos y 'grises' (no publicados oficialmente).Resultados: Muchos documentos se centran en la prevalencia de problemas de salud mental. Sólo unos pocos evalúan primariamente la organización del apoyo psicosocial posterior al desastre y sus determinantes. El material ilustra cómo, en el transcurso de dos décadas, el contexto organizacional del apoyo psicosocial posterior al desastre en los Países Bajos se encuentra influenciado por los cambios en la legislación, los marcos políticos, directrices basadas en la evidencia y la instalación de estructuras formales de expertos para apoyar a gobiernos locales y servicios públicos. Los problemas organizativos recurrentes en respuesta a los eventos están vinculados con aspectos de evaluación interrelacionados, tales como planificación, capacitación, registro, suministro de información y reconocimiento social. Para cada aspecto de evaluación, identificamos los factores que ayudan o dificultan la organización de apoyo psicosocial durante las fases de preparación, aguda y de recuperación.Discusión: La meta-síntesis ilustra que la prestación de servicios psicosociales ha crecido a lo largo del tiempo de un campo mono-disciplinario a uno multidisciplinario. Las colaboraciones inter-profesionales que no son óptimas representan una amenaza recurrente para la calidad del servicio. A pesar de la base de conocimientos desarrollados, el apoyo psicosocial posterior al desastre en los Países Bajos carece de una evaluación sistemática y crítica de su funcionamiento. La profesionalización avanzada lleva aparejado el fortalecimiento de las rutinas de evaluación y aprendizaje.

Attitude toward livestock farming does not influence the earlier observed association between proximity to goat farms and self-reported pneumonia.

Attitudes toward environmental risks may be a source of bias in environmental health studies because concerns about environmental hazards may influence self-reported outcomes. OBJECTIVE: The main aim was to assess whether earlier observed associations between proximity to goat farms and self-reported pneumonia were biased by participants' attitude toward farming. METHODS: We developed an attitude-score for 2,457 participants of the Dutch Livestock Farming and Neighbouring Residents' Health Study (veehouderij en gezondheid omwonenden) by factor analysis of 13 questionnaire items related to attitude toward livestock farming. Linear regression analysis was used to assess associations between attitude and potential determinants. The effect of attitude on the association between goat farm proximity and pneumonia was analyzed by evaluating (1) misclassification of the outcome, (2) effect modification by attitude, and (3) exclusion of participants reporting health problems due to farms in their environment. RESULTS: In general, the study population had a positive attitude toward farming, especially if participants were more familiar with farming. Older participants, females, ex-smokers, and higher-educated individuals had a more negative attitude. Both self-reported respiratory symptoms and exposure to livestock farms were associated with a more negative attitude. Misclassification of self-reported pneumonia was nondifferential with regard to participants' attitude. Furthermore, no indication was found that the association between proximity to goat farms and pneumonia was modified by attitude. Excluding subjects who attributed their health symptoms to livestock farms did also not change the association. CONCLUSIONS: The association between goat farm proximity and pneumonia was not substantially biased by study participants' attitude toward livestock farming.

Residential proximity to livestock farms is associated with a lower prevalence of atopy.

OBJECTIVES: Exposure to farm environments during childhood and adult life seems to reduce the risk of atopic sensitisation. Most studies have been conducted among farmers, but people living in rural areas may have similar protective effects for atopy. This study aims to investigate the association between residential proximity to livestock farms and atopy among non-farming adults living in a rural area in the Netherlands. METHODS: We conducted a cross-sectional study among 2443 adults (20-72 years). Atopy was defined as specific IgE to common allergens and/or total IgE ≥100 IU/mL. Residential proximity to livestock farms was assessed as 1) distance to the nearest pig, poultry, cattle or any farm, 2) number of farms within 500 m and 1000 m, and 3) modelled annual average fine dust emissions from farms within 500 m and 1000 m. Data were analysed with multiple logistic regression and generalised additive models. RESULTS: The prevalence of atopy was 29.8%. Subjects living at short distances from farms (<327 m, first tertile) had a lower odds for atopy compared with subjects living further away (>527 m, third tertile) (OR 0.79, 95% CI 0.63 to 0.98). Significant associations in the same direction were found with distance to the nearest pig or cattle farm. The associations between atopy and livestock farm exposure were somewhat stronger in subjects who grew up on a farm. CONCLUSIONS: Living in close proximity to livestock farms seems to protect against atopy. This study provides evidence that protective effects of early-life and adult farm exposures may extend beyond farming populations.

Healthcare utilisation prior to the diagnosis of inflammatory bowel diseases and the influence of livestock exposure: A longitudinal case-control study.

An increased prevalence of the inflammatory bowel diseases, ulcerative colitis and Crohn's disease, was found amongst residents in a livestock dense area. We hypothesised that exposure to livestock farms might be a substantial environmental factor that contributes to the development of these diseases and that in the lead up to inflammatory bowel diseases potential risk factors can be identified. This study aimed to investigate the contribution of livestock exposure to the development of these diseases and the clinical events prior to the diagnosis. Electronic health records from 2006-2013 of general practices were used. The study population consisted of patients with a new diagnosis of inflammatory bowel diseases resident in areas with a high (n = 141) or lower (n = 109) livestock density. Patients with low back pain (n = 10,469) were used as controls. For those in a livestock dense area, distance to livestock farms was determined. Associations between morbidities and drug prescriptions in the reporting year and three years previous to the diagnosis, and the residential proximity to livestock exposure were investigated with multivariable logistic regression analyses. Acute and chronic morbidity of the gastrointestinal tract and associated drug prescriptions were predictive for the development of inflammatory bowel diseases. In addition, a positive association was found between infections and living within 500 meter of poultry farms and the development of inflammatory bowel diseases [OR: 3.3 (1.1-9.9)]. Nonetheless, overall livestock exposure contributed little to the development of these diseases. These results suggest that exposure to livestock farms on its own contributes minimal to the development of inflammatory bowel diseases. Nonetheless, having infections appeared to be a risk factor for neighbouring residents of poultry farms. More research is warranted to explain the increased prevalence of inflammatory bowel diseases amongst residents in areas with a high density of livestock.

Air Pollution from Livestock Farms Is Associated with Airway Obstruction in Neighboring Residents.

RATIONALE: Livestock farm emissions may not only affect respiratory health of farmers but also of neighboring residents. OBJECTIVES: To explore associations between spatial and temporal variation in pollutant emissions from livestock farms and lung function in a general, nonfarming, rural population in the Netherlands. METHODS: We conducted a cross-sectional study in 2,308 adults (age, 20-72 yr). A pulmonary function test was performed measuring prebronchodilator and post-bronchodilator FEV1, FVC, FEV1/FVC, and maximum mid-expiratory flow (MMEF). Spatial exposure was assessed as (1) number of farms within 500 m and 1,000 m of the home, (2) distance to the nearest farm, and (3) modeled annual average fine dust emissions from farms within 500 m and 1,000 m of the home address. Temporal exposure was assessed as week-average ambient particulate matter <10 µm in diameter and ammonia (NH3) concentrations before lung function measurements. Data were analyzed with generalized additive models (smoothing). MEASUREMENTS AND MAIN RESULTS: A negative association was found between the number of livestock farms within a 1,000-m buffer from the home address and MMEF, which was more pronounced in participants without atopy. No associations were found with other spatial exposure variables. Week-average particulate matter <10 µm in diameter and NH3 levels were negatively associated with FEV1, FEV1/FVC, and MMEF. In a two-pollutant model, only NH3 remained associated. A 25-µg/m3 increase in NH3 was associated with a 2.22% lower FEV1 (95% confidence interval, -3.69 to -0.74), FEV1/FVC of -1.12% (-1.96 to -0.28), and MMEF of -5.67% (-8.80 to -2.55). CONCLUSIONS: Spatial and temporal variation in livestock air pollution emissions are associated with lung function deficits in nonfarming residents.

Spirometry, questionnaire and electronic medical record based COPD in a population survey: Comparing prevalence, level of agreement and associations with potential risk factors.

BACKGROUND: COPD-diagnosis is confirmed by post-bronchodilator (BD) spirometry. However, epidemiological studies often rely on pre-BD spirometry, self-reports, or medical records. This population-based study aims to determine COPD-prevalence based on four different operational definitions and their level of agreement, and to compare associations between COPD-definitions and risk factors. METHODS: COPD-prevalence in 1,793 adults from the general Dutch population (aged 18-70 years) was assessed based on self-reported data, Electronic Medical Records (EMR), and post-BD spirometry: using the FEV1/FVC below the lower limit of normal (LLN) and GOLD fixed cut-off (FEV1/FVC <0.70). Using spirometry as a reference, sensitivity was calculated for self-reported and EMR-based COPD. Associations between COPD and known risk factors were assessed with logistic regression. Data were collected as part of the cross-sectional VGO study (Livestock Farming and Neighboring Residents' Health Study). RESULTS: The highest prevalence was found based on spirometry (GOLD: 10.9%, LLN: 5.9%), followed by self-report (4.6%) and EMR (2.9%). Self-reported or EMR-based COPD identified less than 30% of all COPD-cases based on spirometry. The direction of association between known risk factors and COPD was similar across the four definitions, however, magnitude and significance varied. Especially indicators of allergy were more strongly associated with self-reported COPD compared to the other definitions. CONCLUSIONS: COPD-prevalence varied depending on the used definition. A substantial number of subjects with spirometry-based COPD cannot be identified with questionnaires or medical records which can cause underestimation of COPD-prevalence. The influence of the different COPD-definitions on associations with known risk factors was limited.

Comorbidity and coexisting symptoms and infections presented in general practice by COPD patients: Does livestock density in the residential environment play a role?

OBJECTIVES: Patients with chronic obstructive pulmonary disease (COPD) constitute a potentially susceptible group towards environmental exposures such as livestock farm emissions, given their compromised respiratory health status. The primary aim of this study was to examine the association between livestock exposure and comorbidities and coexisting symptoms and infections in COPD patients. METHODS: Data were collected from 1828 COPD patients (without co-occurring asthma) registered in 23 general practices and living in a rural area with a high livestock density. Prevalence of comorbid diseases/disorders and coexisting symptoms/infections were based on electronic health records from the year 2012. Various indicators of individual exposure to livestock were estimated based on residential addresses, using a geographic information system. RESULTS: At least one comorbid disorder was present in 69% of the COPD patients (especially cardiac disorders and depression, while 49% had at least one coexisting symptom and/or infection (especially upper respiratory tract infections, respiratory symptoms and pneumonia). Half of the COPD-patients resided less than 500m of the nearest farm. Some positive as well as inverse associations were found between the examined outcomes and exposure estimates, although not consistent. CONCLUSIONS: Despite the high prevalence of coexisting chronic and acute conditions presented in primary care by in COPD patients, this investigation found no convincing evidence for an association with livestock exposure estimates. There is a need for a replication of the present findings in studies with a longitudinal design, on different groups of potentially susceptible patients. Future research should also elucidate the biological plausibility of possible protective effects of exposure.

Hepatitis E virus seroprevalence among the general population in a livestock-dense area in the Netherlands: a cross-sectional population-based serological survey.

BACKGROUND: Recent serological studies indicate that hepatitis E virus (HEV) is endemic in industrialised countries. The increasing trend in the number of autochthonous cases of HEV genotype 3 in Western European countries, stresses the importance to get insight in the exact routes of exposure. Pigs are the main animal reservoir, and zoonotic food-borne transmission of HEV is proven. However, infected pigs can excrete large amounts of virus via their faeces enabling environmental transmission of HEV to humans. This might pose a risk for of neighbouring residents of livestock farming. METHODS: Within a large study on the health of people living in the vicinity of livestock farming we performed a cross-sectional population-based serological survey among 2,494 non-farming adults from the general population in a livestock-dense area in the south of the Netherlands. Participants completed risk factor questionnaires and blood samples of 2,422 subjects (median age 58 years, range 20-72) were tested for anti-HEV IgG using an enzyme immune assay (Wantai). The aim of this study was to determine the HEV seroprevalence and to assess whether seropositivity in adults was associated with living in the vicinity of pig farms. RESULTS: The average seroprevalence of HEV was 28.7% (95% CI: 26.9-30.5). Determinants associated with an increased risk for HEV seropositivity were male gender and low level of education. There was a clear trend of increasing prevalence with increasing age (Chi-square test for linear trend, X2 = 83.1; p < 0.001). A high number of pigs within 1,000 m of the residential address was not a risk factor for seropositivity. CONCLUSIONS: This study confirmed the high HEV seroprevalence (29%) in the general population of the Netherlands, but presence of antibodies was not associated with residential proximity to pig farms. The prevalence increased with age from 10% in adolescents to 33% among those aged 50 and above, supporting the assumption of a cumulative lifetime exposure to HEV in the Netherlands as well as a higher infection pressure in the past. Our findings cannot refute the assumption that transmission is primarily food-borne.

Health conditions in rural areas with high livestock density: Analysis of seven consecutive years.

Previous studies investigating health conditions of individuals living near livestock farms generally assessed short time windows. We aimed to take time-specific differences into account and to compare the prevalence of various health conditions over seven consecutive years. The sample consisted of 156,690 individuals registered in 33 general practices in a (rural) area with a high livestock density and 101,015 patients from 23 practices in other (control) areas in the Netherlands. Prevalence of health conditions were assessed using 2007-2013 electronic health record (EHR) data. Two methods were employed to assess exposure: 1) Comparisons between the study and control areas in relation to health problems, 2) Use of individual estimates of livestock exposure (in the study area) based on Geographic Information System (GIS) data. A higher prevalence of chronic bronchitis/bronchiectasis, lower respiratory tract infections and vertiginous syndrome and lower prevalence of respiratory symptoms and emphysema/COPD was found in the study area compared with the control area. A shorter distance to the nearest farm was associated with a lower prevalence of upper respiratory tract infections, respiratory symptoms, asthma, COPD/emphysema, allergic rhinitis, depression, eczema, vertiginous syndrome, dizziness and gastrointestinal infections. Especially exposure to cattle was associated with less health conditions. Living within 500m of mink farms was associated with increased chronic enteritis/ulcerative colitis. Livestock-related exposures did not seem to be an environmental risk factor for the occurrence of health conditions. Nevertheless, lower respiratory tract infections, chronic bronchitis and vertiginous syndrome were more common in the area with a high livestock density. The association between exposure to minks and chronic enteritis/ulcerative colitis remains to be elucidated.

MRSA in persons not living or working on a farm in a livestock-dense area: prevalence and risk factors.

Objectives: MRSA emerged in livestock and persons in contact with livestock is referred to as livestock-associated MRSA (LA-MRSA). We assessed the prevalence and risk factors for MRSA carriage in persons not living or working on a farm. Methods: A cross-sectional study was performed among 2492 adults living in close proximity of livestock farms. Persons working and/or living on farms were excluded. Nasal swabs were cultured using selective media. Participants completed questionnaires and the distance from the residential address to the nearest farm was calculated. The Mann-Whitney U -test was used to compare median distances. Risk factors were explored with logistic regression. Results: Fourteen persons carried MRSA (0.56%; 95% CI 0.32%-0.92%), 10 of which carried LA-MRSA of multiple-locus variable-number tandem repeat analysis complex (MC) 398 (0.40%; 95% CI 0.20%-0.71%). MRSA MC 398 carriers lived significantly closer to the nearest farm than non-carriers (median: 184 versus 402 m; P < 0.01). In bivariate analyses correcting for contact with livestock, this difference remained significant. Conclusions: Although the prevalence was low, living near farms increased the risk of MRSA MC 398 carriage for persons not living or working on a farm. Further research is necessary to identify the transmission routes.

Risk of exacerbations in COPD and asthma patients living in the neighbourhood of livestock farms: Observational study using longitudinal data.

OBJECTIVE: Living in an area with a high density of livestock farms has been associated with adverse respiratory health effects in some studies. As patients with COPD and asthma already have a compromised respiratory function and chronic airway inflammation, they are expected to be at increased risk for adverse respiratory health effects. The objective of this study was to assess the association between livestock exposure and exacerbations in COPD and asthma. METHODS: 899 COPD and 2546 asthma patients from 15 general practices in a rural area with a high livestock density and 933 COPD and 2310 asthma patients from 15 practices in a control area in the Netherlands were included. Occurrence of exacerbations was based on the pharmaceutical treatment of exacerbations in COPD and asthma patients using 2006-2012 prescription data of electronic medical records. Farm exposure was assessed by comparing the study area with the control area, and with individual exposure estimates in the study area using Geographic Information System data. RESULTS: The exacerbation rate was higher in the study area compared with the control area in COPD (IRR: 1.28; 95%CI: 1.06-1.55), but not in asthma patients (IRR: 0.87; 95%CI: 0.72-1.05). In general, individual exposure estimates in the study area were not associated with exacerbations. COPD patients living within a 500m radius of up to12,499 chickens had a 36% higher exacerbation rate (IRR: 1.36; 95%CI: 1.03-1.79). CONCLUSIONS: Living in an area with a high livestock density is a risk factor for exacerbations in COPD patients. The environmental exposure responsible for this increased risk remains to be elucidated.

Doctor-diagnosed health problems in a region with a high density of concentrated animal feeding operations: a cross-sectional study.

BACKGROUND: There is growing interest in health risks of residents living near concentrated animal feeding operations (CAFOs). Previous research mostly focused on swine CAFOs and self-reported respiratory conditions. The aim was to study the association between the presence of swine, poultry, cattle and goat CAFOs and health of Dutch neighbouring residents using electronic medical records from general practitioners (GPs). METHODS: Data for the year 2009 were collected of 119,036 inhabitants of a rural region with a high density of CAFOs using information from GIAB (high exposed population). A comparison was made with GP data from 78,060 inhabitants of rural areas with low densities of CAFOs (low exposed population). Associations between the number of CAFOs near residents' homes and morbidity were determined by multilevel (cross-classified) logistic regression. RESULTS: In 2009, the prevalence of most respiratory and gastrointestinal conditions was similar in the high and low exposed population. Exceptions were pneumonia, atopic eczema and unspecified infectious diseases with an increased prevalence, and sinusitis with a decreased prevalence in the high exposed population. Within the high CAFO density region, the number of poultry, cattle and swine CAFOs near residents' homes was not associated with allergic, respiratory or gastrointestinal conditions. Conversely, each additional goat CAFO within the postal code area of residents' homes significantly increased the odds of unspecified infectious disease and pneumonia by 87 and 41 percent, respectively. CONCLUSIONS: Using GP records, pneumonia and unspecified infectious diseases were positively associated with the number of goat CAFOs near residents' homes, but no association was found between swine, cattle, and poultry CAFOs and respiratory, allergic or gastrointestinal conditions.

Associations between proximity to livestock farms, primary health care visits and self-reported symptoms.

BACKGROUND: Living in a neighbourhood with a high density of livestock farms has been associated with adverse respiratory health effects, but less is known about healthcare utilisation. This study aimed at investigating the associations between livestock exposure and primary health care visits and self-reported symptoms. In addition, we examined the potentially confounding effect of distance from home to general practice. METHODS: Contact data between 2006 and 2009 were obtained from electronic medical records of 54,777 persons registered within 16 general practices in an area with a high density of livestock farms in the Netherlands. Data on self-reported symptoms were used from a cross-sectional sample of 531 patients in 2010. Livestock presence in a 500 m radius from home was computed using Geographic Information System data. RESULTS: In general, livestock exposure was associated with fewer contacts and self-reported symptoms for respiratory and other conditions. The number of poultry within 500 m was positively associated with the number of contacts. A longer distance to general practice was associated with fewer contacts, but did not confound associations. CONCLUSIONS: People living close to livestock farms less often see their general practitioner and report symptoms.