Mainland France Research Articles

Dialysis-network variability in home dialysis use not explained by patient characteristics: a national registry-based cohort study in France.

Although associated with better quality of life and potential economic advantages, home dialysis use varies greatly internationally and appears to be underused in many countries. This study aimed to estimate the dialysis-network variability in home dialysis use and identify factors associated with (i) the uptake in home dialysis, (ii) the proportion of time spent on home dialysis and (iii) home dialysis survival (patient and technique). All adults≥18 years old who had dialysis treatment during 2017-2019 in mainland France were included. Mixed-effects regression models were built to explore factors including patient or residence characteristics and dialysis network associated with variation in home dialysis use. During 2017-2019, 7728/78 757 (9.8%) patients underwent dialysis at least once at home for a total of 120 594/1 508 000 (8%) months. The heterogeneity at the dialysis-network level and to a lesser extent the regional level regarding home dialysis uptake or total time spent was marginally explained by patient characteristics or residence and dialysis-network factors. Between-network heterogeneity was less for patient and technique survival. These results were similar when the analysis was restricted to home peritoneal dialysis or home hemodialysis. Variability between networks in the use of home dialysis was not fully explained by non-modifiable patient and residence characteristics. Our results suggest that to increase home dialysis use in France, one should focus on home dialysis uptake rather than survival. Financial incentives and a quality improvement programme should be implemented at the dialysis-network level to increase home dialysis use.

Research and management priorities for mainland France soils

• Better manage French soils for the agroecological transition. • Reduce our footprint on soils and close the biogeochemical cycles. • Manage French soils to adapt to- and mitigate climate change. • Control soil sealing, land-take and soil contamination in French soils. • Raising soil awareness and develop transfer of technology to help decision making.

Anaplasma capra in sheep and goats on Corsica Island, France: A European lineage within A. capra clade II?

Anaplasmosis is a tick-transmitted disease due to several species of the genus Anaplasma. In 2019, we demonstrated the presence of Anaplasma capra in two deer species at a zoological park in mainland France. As we suspected its presence in Corsica, we surveyed 11 geographically distant sheep or goat farms. Using molecular tools such as nested PCR targeting 16S ribosomal RNA (rRNA), citrate synthase (gltA) and heat-shock protein (groEL) genes, we detected the presence of A. capra on 5/11 farms, in 26/108 blood samples (24%), in sheep as well as in goats. Genotyping and phylogenetic analysis of A. capra revealed that isolates from Corsica island grouped closely with A. capra isolates reported in red deer and swamp deer from a zoological reserve in mainland France, as well as in roe deer from Spain, in a separate and well supported clade within A. capra clade II. This third report of the tick-borne bacterium A. capra in Europe suggests a potentially larger presence of this pathogen on the European continent, on domestic, native as well as wild ruminants, a broad host range already described in Asian countries for this species.

Survival of adult patients with solid cancer in Reunion Island, 1998–2014

Population-based cancer survival is a major indicator of effectiveness of cancer management. This study is the first population-based study to estimate the net survival (NS) of adult cancer patients in Reunion Island, a French overseas department with distinctive epidemiological, cultural, and sociodemographic characteristics. All adult incident cases (n=23,055) of invasive solid tumors diagnosed between 1998 and 2014 and registered in the Reunion Island Cancer Registry were included in the study. The Pohar-Perme estimator was used to estimate 1-, 3-, 5-, and 10-year NS. 5-year NS ranged from 7% (liver in women) to 97% (thyroid cancer in women) for cancers diagnosed between 2006 and 2014. For the most common cancers, the age-standardized 5-year NS of women was 81% for breast cancer, 58% for colorectal cancer and 62% for cervical cancer. For men, the age-standardized 5-year NS was 85% for prostate cancer, 12% for lung cancer, and 52% for colorectal cancer. Age-standardized 5-year NS increased slightly with the period of diagnosis (from 1998-2005 to 2006-2014) for prostate, breast, head and neck, lung, colorectal (women), and stomach (men) cancers, remained stable for colorectal (men) cancer, and decreased slightly for cervical and stomach (women) cancers. Overall, NS was lower in Reunion Island than in mainland France. While the epidemiological, cultural, and sociodemographic characteristics of the Reunionese population likely explain some of the observed differences compared to mainland France, site-specific studies are needed to explore the different determinants of survival in Reunion Island.

Collaborative research protocol to define patient-reported experience measures of the cystic fibrosis care pathway in France: the ExPaParM study

IntroductionIn France, the cystic fibrosis (CF) care pathway is coordinated by multidisciplinary teams from specialised CF centres or transplant centres. It includes the care provided at home or out of hospital, risk prevention in daily life and adjustments to social life, which together contribute to the person’s quality of life. Patient experience is used to describe and evaluate the care and life of patients living with the disease.ObjectivesOur collaborative research aims to identify the most significant areas and criteria that characterise the CF pathway. It will lead to the development of a questionnaire to collect patients' experience, which can be administered to all patients or parents of children registered and followed in the centres. The article describes the protocol developed in partnership with patients and parents of children living with the disease.MethodA multidisciplinary research group brings together researchers, patients, parents of children with CF and health care professionals. The patient partnership is involved in the 4 phases of the protocol: (1) setting up the study, recruiting patient and parent co-researchers, training them in qualitative research methods, defining the situations and profiles of patients in the study population, elaborating the protocol; (2) selecting the study sites, recruiting participants, carrying out semi-structured interviews, analysing verbatims using the grounded theory approach; (3) co-elaborating Patient-Reported Experience Measures (PREM) questionnaires adapted to the 4 types of participants: parents, adolescents, non-transplanted adults and transplanted adults; (4) validating the construct with participants and professionals from the study centres.ResultsThe protocol obtained a favourable opinion from the Ethics Evaluation Committee of INSERM (IRB00003888—no. 20-700). Training was provided to the 5 patients and 2 parent co-researchers to enable them to participate effectively in the research. Eleven centres participated in the recruitment of participants in mainland France and Reunion Island. Eighty hours of interviews were conducted.DiscussionThe PREM questionnaires to be elaborated will have to undergo psychometric validation before being used by the actors of the CF network to assess the impact on the care pathways of quality approaches or new therapies available in cystic fibrosis.Trial Registration Registry: IRB00003888 – no. 20-700. Issue date: 06/09/2020.

Extension de la vaccination contre les HPV aux garçons : enquête auprès de familles et de médecins généralistes

As part of an analysis on the extension of the HPV vaccination to French boys, the French National Cancer Institute (INCa) and the French National Authority for Health (HAS) have conducted in collaboration a survey on HPV vaccine acceptance in July 2019. This survey was completed by parents of children aged 11-19 and general practitioners (GPs). Questions focused on their representations, practices and intentions in the context of the future policy change allowing boys to get vaccinated against HPV. The survey was conducted between June 20 and July 12, 2019. It focused on two populations: a nationally representative sample of parents with at least one girl aged 11-19 and/or one boy aged 11-14 (n=1984) and a representative sample of GPs in mainland France. Data were collected through a web-based questionnaire with a mean completion time of 10minutes for parents and GPs. The quota method was applied to ensure the representative nature of the samples based on (i) gender, age, children (girl aged 11-14 and/or boy aged 11-14) of the household, socio-professional category of the "head of the household", size of urban area and region for the parents' sample and based on (ii) gender, age, region and type of practice for the GPs' sample. Although most GPs were very favourable towards HPV vaccination (94%), they considered it one of the most challenging vaccinations to get parents to adhere to (82%). A notable percentage of parents have unfavourable opinions towards HPV vaccination (25%). The three main barriers cited by parents of non-vaccinated girls were: the fear of adverse effects, the lack of information, and the fact that the GP did not propose it. Regarding the extension of HPV vaccination to boys, 84% of GPs would recommend this vaccination to boys if it was included in the vaccination schedule, and 88% of those who did not routinely recommend HPV vaccination to girls would be more likely to offer it to girls if the extension was recommended.

Feasibility of developing classical biological control solutions for the herbaceous weed Allium triquetrum in Australia

ABSTRACT Allium triquetrum L. (Amaryllidaceae), a bulbiferous monocot, is native to the Mediterranean. It was introduced to Australia in the early 1900s, where it has subsequently become a significant invader of temperate forests throughout south-eastern Australia. Intensive chemical and mechanical control methods can suppress A. triquetrum infestations at the local scale for short periods of time but remain ineffective at sustainably curtailing its invasion at landscape and regional scales. In this context, we undertook field surveys across the Mediterranean (mainland France, Corsica, Sardinia) to determine the feasibility of developing classical biological control solutions for A. triquetrum in Australia. Despite extensive sampling (i.e. 30 surveys at 18 sites over three growing seasons), very few phytophagous arthropod and fungal pathogen taxa were detected on A. triquetrum. The most common arthropod species were the flies Phytomyza gymnostoma and Delia hirticrura, the weevil Oprohinus consputus and the moth Hysterophora maculosana. All identified arthropod taxa were considered generalists, having been found on other plant species, and some are known pests of cultivated Allium species. Twenty-one different fungal isolates were recovered from A. triquetrum, with most considered as saprophytic, secondary/opportunistic pathogens that probably infected already-damaged A. triquetrum leaves. Only four fungal taxa were found to be primary pathogens of A. triquetrum but have been recorded to infect other plant species. None of these enemy taxa were deemed to be suitable candidate biocontrol agents to help manage A. triquetrum invasion in Australia. Future research directions for improved A. triquetrum management in Australia are discussed in this paper.

Burden of gastric and digestive cancers in the French Caribbean: perspectives from population-based cancer registries of Martinique, Guadeloupe and French Guiana (2007–2014)

ObjectivesData from population-based cancer registries contribute to improving our knowledge of digestive cancer trends worldwide. In this study, we present cancer incidence and mortality in Guadeloupe, French Guiana and Martinique...

History of probabilistic seismic hazard assessment studies and seismic zonations in mainland France

This article aims to provide an overview of successive seismic zonations in mainland France and probabilistic seismic hazard studies performed over the previous ≈30 years. A short presentation is given on the engineering and regulatory framework that shapes the background of seismic zonation and hazard studies, followed by a scientific overview of published probabilistic seismic hazard estimations. The components of these past PSHA studies are summarized (seismic source models, ground-motion models, management of uncertainties). The evolution of hazard estimates with time is displayed for a set of representative cities. Finally, three generations of official seismic zonation maps in France are presented (1967, 1986, 2004), and the evolution of methods and results is highlighted. This review shows that the academic community has previously had little involvement in this topic. As current zonation relies on outdated models, there is an opportunity for scientific and engineering communities to efficiently work together to build the next generation of probabilistic seismic hazard models for France.

New perspectives in studying active faults in metropolitan France: the “Active faults France” (FACT/ATS) research axis from the Resif-Epos consortium

Mainland France is part of a plate interior with a strong structural heritage, undergoing a low rate of deformation, where destructive earthquakes can nevertheless occur. In this paper, we emphasize that the knowledge of active faults is still largely fragmentary, and that significant efforts are needed to generate robust data, in particular on the numerous faults, that still lack any study. This is the aim of the “Failles ACTives France” (FACT) axis launched in the framework of the Transverse Seismicity Action (ATS) of the Resif-Epos consortium. We present some recent investigations carried out along suspected active faults in mountainous areas, their forelands and remote lowlands, which implement new approaches and new tools, and allow characterizing their Quaternary activity.

Urological Cancers in French Overseas Territories: A Population-Based Cancer Registry Pooled Analysis in Martinique, Guadeloupe and French Guiana (2007–2014)

PurposeProstate cancer is the most common cancer in the Caribbean. We present world-standardized incidence (WSI) and mortality (WSM) rates for urological cancers for French overseas territories.Materials and MethodsStandardized incidence ratio (SIR) and standardized mortality ratio (SMR) were calculated for 2008–2014, 2007–2014 and 2010–2014 in Guadeloupe, Martinique and French Guiana.ResultsFor prostate cancer, in Guadeloupe and Martinique, the WSI rates are among the highest in the world (173.0 and 164.5 per 100,000 person-years) and 94.4 in French Guiana. Mortality remains more than twice that observed in mainland France, at 23.0 in Guadeloupe and Martinique, and 16.9 in French Guiana.For bladder cancer, WSI rates were 5.9, 4.9 and 4.1 in men, and 1.9, 1.4 and 1.3 in women, in French Guiana, Guadeloupe and Martinique. WSM rates from bladder varied from 1.5 in French Guiana to 1.8 in Guadeloupe and 2.0 in Martinique in men. In women, it ranges from 0.2 in French Guiana to 0.5 in Guadeloupe and 1.1 in Martinique. Regarding kidney, WSI rates in men are 4.3 in Martinique, 5.2 in Guadeloupe and 6.1 in French Guiana, and 2.3, 2.5 and 3.4, respectively, in women. Mortality rates in men were 1.7 in Guadeloupe, 1.4 in Martinique, and 1.5 in French Guiana, while in women, rates were 0.8 in Guadeloupe and Martinique and 0.6 in French Guiana. All these rates are lower than in mainland France.ConclusionsIdentifying the profile of patients with urological cancers is key to understanding the needs of patients in these regions.

Pathological Significance of GLUT-1 Expression in Breast Cancer Cells in Diabetic and Obese Patients: The French Guiana Study.

Simple SummaryThis study describes the clinical, histological, and molecular features of breast cancer in French Guiana, and characterizes the expression of the tumor metabolic marker GLUT-1 in breast cancers cells in diabetic and obese patients compared to a control group. This study reveals an overall overexpression of GLUT-1 in 60% of invasive breast carcinomas and in all medullary pattern and carcinoma in situ lesions. Our results highlight the potential role of GLUT-1 as a tumor metabolic prognostic marker and also as an interesting target therapy, independently of patient metabolic disorder.The prevalence of obesity and type 2 diabetes is higher in French Guiana compared to mainland France. These metabolic disorders are associated with an increased risk of cancer. One of the factors involved is hyperinsulinemia that promotes the action of glucose transporter 1 (GLUT-1). The objective of this study is to characterize the expression of GLUT-1 in breast cancers cells in diabetic and obese patients compared to those who are not and to describe the clinical and histological prognostic factors of breast cancer in this population. We conducted a monocentric study including patients with breast cancer diagnosed between 2014 and 2020. Patients were classified into three groups: diabetes, obesity, and control group. The GLUT-1 expression was assessed by immunohistochemistry. In total, 199 patients were included in this study. The median age was 53.5 years, and the median tumor size was 2.8 cm. Luminal A was the most frequent molecular type (58.1%), followed by the triple-negative type (19.9%). The breast cancer in our population was characterized by a younger age at diagnosis, more aggressive molecular types, and larger tumor size. Thus, we suggest the advancement of the age of breast cancer screening in this territory. A total of 144 patients (31 diabetes, 22 obese, and 91 control group) were included for the study of GLUT-1 expression. Overexpression of GLUT-1 was observed in 60.4% of cases and in all carcinoma in situ lesions. GLUT-1 overexpression was associated with more aggressive cancers. This overexpression is correlated with high histological grade, high proliferation index, and aggressive molecular types. Our study found no difference in GLUT-1 expression between the diabetic or obese patients and the control group. These results highlight the potential role of GLUT-1 as a tumor metabolic prognostic marker and also as an interesting target therapy, independently of patient metabolic disorder.

Stochastic Generator of Earthquakes for Mainland France

Mainland France is characterized by low-to-moderate seismic activity, yet it is known that major earthquakes could strike this territory (e.g., Liguria in 1887 or Basel in 1356). Assessing this French seismic hazard is thus necessary in order to support building codes and to lead prevention actions towards the population. The Probabilistic Seismic Hazard Assessment (PSHA) is the classical approach used to estimate the seismic hazard. One way to apply PSHA is to generate synthetic earthquakes by propagating information from past seismicity and building various seismic scenarios. In this paper, we present an implementation of a stochastic generator of earthquakes and discuss its relevance to mimic the seismicity of low-to-moderate seismic areas. The proposed stochastic generator produces independent events (main shocks) and their correlated seismicity (only aftershocks). Main shocks are simulated first in time and magnitude considering all available data in the area, and then localized in space with the use of a probability map and regionalization. Aftershocks are simulated around main shocks by considering both the seismic moment ratio and distribution of the aftershock’s proportion. The generator is tested with mainland France data.

First insights on the diversity of the genus Psychoda Latreille (Diptera: Psychodidae) in Corsica using DNA barcoding

Among the 44 European Psychoda species identified to date, we expected to observe in Corsica species with large distribution ranges and/or that are frequent in adjacent territories (i.e. south mainland France, mainland Italy, and Sardinia). Each studied specimen was morphologically identified and then barcoded using cytochrome c oxidase subunit I (COI) and subunit II (COII) to confirm its identification, and to detect potential cryptic species. From 211 mounted specimens, 16 Psychoda sensu lato morphotypes were recorded in Corsica and mainland France. While 14 out of the 15 species recorded in Corsica are new records for the island, two species are also new records for France and Europe, P. (Psychodocha) uncinula Quate, 1954 and P. (Chodopsycha) divaricata Duckhouse, 1968. Moreover, our barcoding approach allowed us to detect 18 haplotypes in total, including three undescribed Corsican haplotype complexes, namely P. (Tinearia) alternata, P. (Logima) satchelli and P. (Psychodocha) cinerea. With only mitochondrial COI barcodes, it cannot be asserted whether these complexes represent the within-species coexistence of various haplotypes or the existence of distinct cryptic species. In BOLD (Barcode of Life Datasystems), only 30 out of the 58 barcode indice numéros (BINs) corresponding to the genus Psychoda have a species name. All of the COI barcodes generated in this study already exist in BOLD, suggesting that the barcodes of most of the temperate Psychoda diversity are already known, but not properly named.

Specificities of the Diabetic Population in French Guiana: The Health Barometer Survey.

This study aims to identify the epidemiological and social characteristics of the diabetic population in French Guiana. The prevalence of diabetes is very high in the French overseas departments. French Guiana is, however, a very atypical territory, closer in the epidemiological field to Latin America than European and French standards. To perform a descriptive analysis of variables related to renouncing medical care, social parameters, and use of healthcare services. A two-stage random sample of 1390 individuals aged 30 to 75 years was surveyed by telephone, and screening was initially done for diabetic versus non-diabetic individuals. Logistic regression was fitted on the sample to adjust for potential confounding factors. A Kaplan-Meier analysis showed the risk of diabetes as a function of the age of onset. The prevalence rate of diabetes was 9.3%, particularly among women, for whom 20% had a history of gestational diabetes. Excess weight and obesity were found in 60% of people with diabetes. The diabetic individuals in French Guiana were younger than those in mainland France, and 30% of people with diabetes were on insulin. They often reported sleep problems, and their health status was described as poor. People with diabetes did not regularly consult a doctor and were very rarely followed up by a specialist. The prevalence rate of diabetes and obesity in French Guiana was one of the highest among the French territories, with specific vulnerabilities requiring to be addressed by local health policies.

Temperature inversions in France – Part A: time variations

Temperature inversions in mainland France are computed using a network of 859 sampling sites spread as evenly as possible across the country. Each site comprises a high station located within 30 km of the low station with which it is paired. We use the daily minimum (tn) and maximum (tx) temperatures from Météo-France weather stations over 10 years (2008–2017). The time variations of three inversion characteristics (frequency, intensity, and duration) are explored. The primary result is the high frequency of inversions. On average, for the 859 sites, tn-inversions occur on 63% of days and tx-inversions on 22.6%. Inversion intensity is usually weak, the mode being 2°C for tn and 1°C for tx. However, high intensities may be reached (maximum 23.6°C for tn and 22.6°C for tx). The longest sequence of isolated tn-inversions (the inversion is destroyed in the daytime but recurs over several days) ran for more than four months (126 days). Such inversions occur most frequently from August to October. The longest sequence of isolated tx-inversions (the inversion is destroyed overnight) ran for 38 days. Such inversions are most common from November to February. The longest persistent inversion (night and day) lasted 88 days. Persistent inversions occur most frequently from November to January. The results as a whole reveal a number of original points: the existence of a large number of tx-inversion sequences, the seasonal pattern very clearly differentiating tn- and tx-inversions, and the significance of atmospheric conditions.

A long-term monitoring database on fish and crayfish species in French rivers

The data presented here cover ∼4 decades of electrofishing surveys in mainland France rivers. Despite some changes in field protocols and sampling site locations over time, the ASPE database offers a unique set of 47,869 georeferenced and standardised sampling surveys. Fish individuals are identified to species, measured and weighted. Additional information encompasses habitat features as well as “river health” assessment by two fish-based indices. Though preferentially focused on fishes, the surveys also report crayfish data. Numerous studies have been already published using these data, mainly on the fields of macroecology, community and/or population ecology and bioassessment. However, we believe much more knowledge can be gained from the database in fields such as population dynamics or conservation practices in the context of global change.

Use of electroconvulsive therapy for individuals receiving inpatient psychiatric care on a nationwide scale in France: Variations linked to health care supply

BackgroundA comprehensive understanding of variations in the use of electroconvulsive therapy (ECT) among health care providers in charge of ECT referrals is lacking. ObjectiveOur objectives were to document ECT use and its variations on a nationwide scale in France and to identify the factors that were significantly associated with these variations. MethodsAdministrative health claims data on hospitalization were used to perform a descriptive analysis of ECT use for adult patients receiving inpatient psychiatric care in mainland France in 2019 and its variations across hospitals in charge of ECT referrals. Based on a conceptual framework drawn from the literature on medical practice variations, a multilevel logistic regression was then conducted to identify patients, hospitals and contextual characteristics that were significantly associated with ECT treatment using non-ECT-treated patients receiving inpatient psychiatric care as the reference population. ResultsPatients receiving ECT (n = 3288) were older, more frequently female and had more severe diagnoses than other patients seen in inpatient care (n = 295,678). Significant variations were observed in the rate of ECT use across hospitals (n = 468), with a coefficient of variation largely above one. In the multivariable analysis, ECT treatment was associated with patient characteristics (which accounted for 6% of the variations) but also with characteristics of the hospitals and their environments (44% of the variations), including the type of hospital and its distance to the closest facility providing ECT. ConclusionsVariations in ECT use were strongly linked to health care supply characteristics, which raises questions about access to quality mental health care.

Time trend in excess mortality in children with type 1 diabetes from 1987 to 2016 in mainland France.

Mortality risk for children with type 1 diabetes (T1D) is unknown in France and their causes of death are not well documented. To determine the standardized mortality ratios (SMRs) and causes of death in children aged 1-14 years with T1D from 1987 to 2016. The French Center for Epidemiology on Medical Causes of Death collected all death certificates in mainland France. SMRs, corrected SMRs (accounting for missing cases of deaths unrelated to diabetes), and 95% confidence intervals were calculated. Of 146 deaths with the contribution of diabetes, 97 were due to T1D. Mean age at death of the subjects with T1D was 8.8± 4.1 years (54% males). The cause of death was diabetic ketoacidosis (DKA) in 58% of the cases (70% in subjects 1-4 years), hypoglycemia or dead-in-bed syndrome in 4%, related to diabetes but not described in 24%, and unrelated to diabetes in 14%. The SMRs showed a significant decrease across the years, except for the 1-4 age group. In the last decade (2007-2016), the crude and corrected SMRs were significantly different from 1 in the 1-4 age group (5.4 [2.3; 10.7] and 6.1 [2.8; 11.5]), no longer significant in the 5-9 age group (1.7 [0.6; 4.0] and 2.1 [0.8; 4.5]) and borderline significant in the 10-14 age group (1.7 [0.8; 3.2] and 2.3 [1.2; 4.0]). Children with T1D aged 1-4 years still had a high mortality rate. Their needs for early recognition and safe management of diabetes are not being met.

Erythemal and vitamin D weighted solar UV dose-rates and doses estimated from measurements in mainland France and on Réunion Island.

Solar UV radiation causes beneficial and detrimental changes in human health. International and national Health agencies recommend avoiding sun exposure when the solar rays are strongest (typically 2h before and after solar noon). In this study we detail and refine such recommendations. We estimated biologically-effective radiation (inductive of erythema and pre-vitamin D) using spectral solar UV radiation measurements on a horizontal plane at three French sites equipped with spectroradiometers: Villeneuve d'Ascq (VDA) (North of France); Observatoire de Haute-Provence (OHP) (French Southern Alps); and Saint-Denis de La Réunion (SDR) on Réunion Island, in the Indian Ocean. These sites are very different: VDA is a semi-urban site in a flat region, OHP a rural mountainous site and SDR a coastal urban site on a small mountainous island. Biologically active radiation was analyzed by studying erythema induction and measuring pre-vitamin D synthesis. Dose-rates, doses and times for sunburn induction and vitamin D production were derived. Regarding the level of vitamin D dose considered here (1000IU), we found that at mainland sites time required for vitamin D synthesis was relatively long, even around solar noon, in winter months this could be 2-3h for phototype II individuals exposing their face and hands. In the tropics vitamin D could always be synthesized in a reasonable time (e.g. 20min in winter). By contrast, in summer, the required duration times (exposing face, hands, arms and legs) are very short, approximately 2-4min on the mainland and 1min in the tropics for phototype II individuals. In all skin phototypes the duration of sun exposure required to induce erythema was generally longer than that to produce vitamin D. These quantitative results, obtained using an instrument measuring on a horizontal plane and with an unobstructed view, do not represent realistic values for human exposure. To account for realistic human body exposure, received doses and times of exposure were adjusted. Our study shows that, mostly in summer, the time periods where limited solar exposure is recommended should be extended, especially at low latitude locations.