Spectrum Bias and Individual Strengths of SARS-CoV-2 Serological Tests—A Population-Based Evaluation

Antibody testing for determining the SARS-CoV-2 serostatus was rapidly introduced in early 2020 and since then has been gaining special emphasis regarding correlates of protection. With limited access to representative samples with known SARS-CoV-2 infection status during the initial period of test development and validation, spectrum bias has to be considered when moving from a “test establishment setting” to population-based settings, in which antibody testing is currently implemented. To provide insights into the presence and magnitude of spectrum bias and to estimate performance measures of antibody testing in a population-based environment, we compared SARS-CoV-2 neutralization to a battery of serological tests and latent class analyses (LCA) in a subgroup (n = 856) of the larger population based TiKoCo-19 cohort (n = 4185). Regarding spectrum bias, we could proof notable differences in test sensitivities and specificities when moving to a population-based setting, with larger effects visible in earlier registered tests. While in the population-based setting the two Roche ELECSYS anti-SARS-CoV-2 tests outperformed every other test and even LCA regarding sensitivity and specificity in dichotomous testing, they didn’t provide satisfying quantitative correlation with neutralization capacity. In contrast, our in-house anti SARS-CoV-2-Spike receptor binding domain (RBD) IgG-ELISA (enzyme-linked-immunosorbant assay) though inferior in dichotomous testing, provided satisfactory quantitative correlation and may thus represent a better correlate of protection. In summary, all tests, led by the two Roche tests, provided sufficient accuracy for dichotomous identification of neutralizing sera, with increasing spectrum bias visible in earlier registered tests, while the majority of tests, except the RBD-ELISA, didn’t provide satisfactory quantitative correlations

Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany

Herein, we provide results from a prospective population-based longitudinal follow-up (FU) SARS-CoV-2 serosurveillance study in Tirschenreuth, the county which was hit hardest in Germany in spring 2020 and early 2021. Of 4203 individuals aged 14 years or older enrolled at baseline (BL, June 2020), 3546 participated at FU1 (November 2020) and 3391 at FU2 (April 2021). Key metrics comprising standardized seroprevalence, surveillance detection ratio (SDR), infection fatality ratio (IFR) and success of the vaccination campaign were derived using the Roche N- and S-Elecsys anti-SARS-CoV-2 test together with a self-administered questionnaire. N-seropositivity at BL was 9.2% (1st wave). While we observed a low new seropositivity between BL and FU1 (0.9%), the combined 2nd and 3rd wave accounted for 6.1% new N-seropositives between FU1 and FU2 (ever seropositives at FU2: 15.4%). The SDR decreased from 5.4 (BL) to 1.1 (FU2) highlighting the success of massively increased testing in the population. The IFR based on a combination of serology and registration data resulted in 3.3% between November 2020 and April 2021 compared to 2.3% until June 2020. Although IFRs were consistently higher at FU2 compared to BL across age-groups, highest among individuals aged 70+ (18.3% versus 10.7%, respectively), observed differences were within statistical uncertainty bounds. While municipalities with senior care homes showed a higher IFR at BL (3.0% with senior care home vs. 0.7% w/o), this effect diminished at FU2 (3.4% vs. 2.9%). In April 2021 (FU2), vaccination rate in the elderly was high (>77.4%, age-group 80+)

Estimates and determinants of SARS-CoV-2 seroprevalence and infection fatality ratio using latent class analysis: the population-based Tirschenreuth study in the hardest-hit German county in spring 2020

SARS-CoV-2 infection fatality ratios (IFR) remain controversially discussed with implications for political measures. The German county of Tirschenreuth suffered a severe SARS-CoV-2 outbreak in spring 2020, with particularly high case fatality ratio (CFR). To estimate seroprevalence, underreported infections, and IFR for the Tirschenreuth population aged ≥14 years in June/July 2020, we conducted a population-based study including home visits for the elderly, and analyzed 4203 participants for SARS-CoV-2 antibodies via three antibody tests. Latent class analysis yielded 8.6% standardized county-wide seroprevalence, a factor of underreported infections of 5.0, and 2.5% overall IFR. Seroprevalence was two-fold higher among medical workers and one third among current smokers with similar proportions of registered infections. While seroprevalence did not show an age-trend, the factor of underreported infections was 12.2 in the young versus 1.7 for ≥85-year-old. Age-specific IFRs were <0.5% below 60 years of age, 1.0% for age 60–69, and 13.2% for age 70+. Senior care homes accounted for 45% of COVID-19-related deaths, reflected by an IFR of 7.5% among individuals aged 70+ and an overall IFR of 1.4% when excluding senior care home residents from our computation. Our data underscore senior care home infections as key determinant of IFR additionally to age, insufficient targeted testing in the young, and the need for further investigations on behavioral or molecular causes of the fewer infections among current smokers

Protection from Ultraviolet Radiation during Childhood: The Parental Perspective in Bavaria

During childhood, parents play a vital role in sun protection of their children. Their guidance is essential for avoiding excessive exposure to ultraviolet (UV) radiation, a risk factor for developing skin cancer in later life. In a population-based cross-sectional study conducted between October 2011 and February 2012, we assessed how 3281 parents implemented sun protection for their three- to six-year-old children in practice. In particular, clothing, shade-seeking behavior, wearing of sunhats and sunglasses, use of sunscreens and the amount of time spent outdoors were ascertained in two settings (beach, garden/playground). The results showed that the overall level of parental sun protection for their children in the beach setting, and to a lesser extent also in the everyday outdoor setting, is relatively high. Using sunscreens with a high sun protection factor and instructing children to wear a sunhat were very common. Lesser attention was paid to sun-protective clothing, seeking the shade and wearing sunglasses. The amount of time spent outdoors during summer days was high. Therefore, the recommendation to completely avoid sun exposure during peak UV times around noon during summertime needs to be reinforced. In addition, the observed difference in the protective behavior between the beach and an everyday outdoor setting points to the necessity to encourage better sun protection for children also in outdoor activities of daily living

The Role of the Global Solar UV Index for Sun Protection of Children in German Kindergartens

More than twenty-five years ago, the Global Solar UV index (UVI) was introduced as a simple means of visualizing the intensity of ultraviolet radiation and to alert people to the need for sun protection. In our survey, among directors of 436 kindergartens in southern Germany we investigated the level of awareness and knowledge about the UVI as well as the practical consequences for sun protection in kindergartens. Less than half of the directors (n = 208, 47.7%) had ever heard of the UVI, and only a small minority of them (n = 34, 8.7%) used the daily UVI information to adapt sun protective measures in their kindergartens. Detailed knowledge about the UVI was a rarity among the respondents. The proportion of respondents with self-perceived detailed UVI knowledge was five times higher than the actual knowledge assessed by an in-depth structured interview using open-ended questions about the UVI (14.2% vs. 2.8%). No clear relationship between UVI awareness, knowledge, and use and directors’ age and gender was found. The UVI-related variables also showed no association with directors’ knowledge of risk factors for skin cancer and their attitudes towards tanned skin. Overall, the results paint a sobering picture regarding the penetration of the UVI into sun protection policies of German kindergartens. Future public health campaigns should aim to increase the awareness and understanding of the UVI as well as its relevance for sun protection of children

Shedding Light on the Shade: How Nurseries Protect Their Children from Ultraviolet Radiation

Minimizing exposure to ultraviolet radiation (UVR) is strongly recommended as the most important primary prevention measure regarding skin cancer. The responsibility for adequate sun protection of young children lies with their parents and external caregivers. Since a high proportion of 3- to 6-year-old children in Germany attend nurseries, the practice of sun protection in this setting was assessed. A survey was conducted in 246 nurseries in southern Germany during spring and summer of 2014 and 2015. Shade coverage in the outdoor area of the nursery was assessed by study team members and UVR protective behavior of staff was assessed by an interview with the directors. On average, 52% of the entire outdoor area and 65% of the children’s outdoor play area were covered by shade, with a significant difference between nurseries of different sizes, pointing to a better shade coverage in larger nurseries. The daily outdoor stay was not regularly scheduled before or after peak sun intensity hours around noon to avoid intense UVR exposure. General sun protection rules were present in the majority of the nurseries and addressed predominantly wearing sunhats and applying sunscreen. Our findings show that current sun protection recommendations for children are only partially met in nurseries and indicate a lower level of sun protection in small institutions. Especially, avoidance of excessive exposure to UVR around noon and the importance of shade provision over play structures needs to be emphasized in future information campaigns

Public Health Messages Associated with the Low Exposure Category of the UV Index Need Reconsideration

Overexposure to ultraviolet (UV) radiation is the main modifiable risk factor for skin cancer. The Global Solar Ultraviolet Index (UVI) was introduced as a tool to visualize the intensity of UV radiation on a certain day which should enable and encourage people to take appropriate protective measures. The exposure category ‘low’ of the UVI, including values from 0 to 2, was linked to the health message ‘No protection required’ by the World Health Organization and collaborating centres. However, published evidence corroborating this advice is scarce. Therefore, we analysed ambient erythemal irradiance data of 14,431 daily UVI time series of low UVI days. Data were gathered at nine stations of the German solar UV monitoring networkcovering all major climate areas in Germanyin the years 2007–2016. We compared ambient erythemal doses calculated for various time intervals with average minimal erythemal doses (MEDs) of the Caucasian Fitzpatrick skin phototypes I-IV to assess the potential for skin damage arising from sun exposure on days with low UVI values. The most common months for the occurrence of days with low UVI values in our dataset were January and December, February and November, and March and October for UVI 0, 1 and 2, respectively. Our results indicate that on days with a UVI value of 0, risk of deterministic radiation injury (solar erythema) is negligible. Conversely, the above-mentioned health message appears misleading when melano-compromised individuals spend several hours outdoors on days with a UVI value of 2, as median doses exceed the MEDs of Fitzpatrick skin types I and II after an exposure duration of only 2 h around solar noon. Under very rare specific circumstances, MEDs of those two most sensitive skin types can also be exceeded even on days with UVI 1. Hence, two aspects of current public health messages may need reconsideration: on the one hand, the health message related to an ‘innocuous level’ of the UVI and, on the other hand, a possible adaption of UVI-related health messages to different skin types

The extent of public awareness, understanding and use of the Global Solar UV index as a worldwide health promotion instrument to improve sun protection: protocol for a systematic review

Introduction (Over)exposure to ultraviolet radiation is a major risk factor for skin cancer. The Global Solar Ultraviolet Index (UVI) was introduced by the WHO and partner organisations in 1995 as a simple measure of the intensity of solar UV radiation, providing guidance for the population to use appropriate sun protective measures. Little is known about the impact of the UVI on actual sun protection behaviour. Our systematic review aims to assess global levels of awareness, understanding and use of the UVI as prerequisites for the preventive effectiveness of this public health tool. Methods and analysis Systematic searches will be performed in 10 electronic literature databases including Medline, Scopus and Web of Science–Core Collection, two clinical trials registries and at least two grey literature databases (OpenGrey, Bielefeld Academic Search Engine). Additional literature sources will be retrieved using hand search of reference lists of included studies and snowballing methods. We will include studies with all types of quantitative study designs and participants reporting on at least one outcome in the three main categories (i) awareness, (ii) understanding and (iii) use of the UVI. We will assess the risk of bias within studies with an abbreviated version of the AXIS tool, designed specifically for cross-sectional studies. As we expect large heterogeneity in outcomes, we will conduct a narrative synthesis of results instead of a meta-analysis. Ethics and dissemination Ethical approval and patient consent are not required as this is a systematic review based on published studies. The results of this study will be published in an international peer-reviewed journal. Prospero registration number CRD42018093693

Public Health Messages Associated with Low UV Index Values Need Reconsideration

Overexposure to ultraviolet (UV) radiation is the main modifiable risk factor for skin cancer. The Global Solar Ultraviolet Index (UVI) was introduced as a tool to visualize the intensity of UV radiation on a certain day, which should enable and encourage people to take appropriate protective measures. The ‘low’ exposure category of the UVI, defined by a rounded UVI value of 0, 1 or 2, was linked to the health message ‘No protection required’ by the World Health Organization and partner organizations. However, published evidence corroborating this advice is not available. To evaluate the erythemal risk of low UVI days, we analyzed 14,431 daily time series of ambient erythemal irradiance data measured at nine stations of the German solar UV monitoring network during the years 2007–2016. We analyzed the proportion of days in the sample for which ambient erythemal doses calculated for various time intervals exceed average minimal erythemal doses (MEDs) of the Fitzpatrick skin phototypes I–VI to assess the potential for erythema arising from sun exposure on days with low UVI values. Additionally, we calculated for each day the minimum exposure duration needed to receive one MED. Our results indicate that on days with a UVI value of 0, risk of erythema is indeed negligible. Conversely, the abovementioned health message appears misleading when melano-compromised individuals (skin type I and II) spend more than 1.5 hours outdoors on days with a UVI value of 2. Under rare circumstances of prolonged exposure, MEDs of the two most sensitive skin types can also be exceeded even on days with a UVI value of 1. Hence, current WHO guidance for sun protection on days with low UVI values needs reconsideration

Sun Protection and Tanning Behaviors in Caregivers: Prevalence, Determinants, and Associations with Children's Behaviors.

The association between skin cancer and ultraviolet radiation (UVR) is well established, and sun protection behavior represents an important preventative measure. In children, caregivers play a key role in this regard. The subject of this study was threefold: whether caregivers of 1 to 11 year-old children are more likely to use sun protection measures compared to non-caregivers, whether considering oneself a role model is associated with sun protection behaviors, and whether their sun protection and risk behaviors are related to children's behaviors. We used data from the 2020 wave of the National Cancer Aid Monitoring (NCAM) comprised of 4000 individuals (including 554 caregivers of at least one child aged 1-10 years) aged 16 to 65 years and living in Germany. Data were collected through telephone interviews between October and December 2020. No significant differences between caregivers and non-caregivers regarding sun protection and risk behaviors were identified (except tanning on vacation). In both groups, sun protection behaviors were deficient. Caregivers who considered themselves role models concerning sun safety were more likely to use sun protection measures (e.g., using sunscreen on the face: OR = 5.08, p &lt; 0.001). In addition, caregivers' sun protection behaviors were positively associated with children's behaviors. Caregivers being highly protected against UVR were more likely to report the use of different measures by/in the child (mean = 4.03), compared to caregivers with medium (3.41) and low (2.97, p &lt; 0.001) protection levels. However, we also found that caregivers' risk behavior was associated with children's reported risk behavior. For future prevention, it might be worth focusing on the aspect of caregivers serving as role models. A comprehensive public-health strategy is needed, including key figures such as pediatricians to prevent today's children from developing skin cancer in later life