Suppression of a SARS-CoV-2 outbreak in the Italian municipality of Vo'

Test sensitivity is secondary to frequency and turnaround time for COVID-19 surveillance

The COVID-19 pandemic has created a public health crisis. Because SARS-CoV-2 can spread from individuals with pre-symptomatic, symptomatic, and asymptomatic infections, the re-opening of societies and the control of virus spread will be facilitated by robust surveillance, for which virus testing will often be central. After infection, individuals undergo a period of incubation during which viral titers are usually too low to detect, followed by an exponential viral growth, leading to a peak viral load and infectiousness, and ending with declining viral levels and clearance. Given the pattern of viral load kinetics, we model surveillance effectiveness considering test sensitivities, frequency, and sample-to-answer reporting time. These results demonstrate that effective surveillance depends largely on frequency of testing and the speed of reporting, and is only marginally improved by high test sensitivity. We therefore conclude that surveillance should prioritize accessibility, frequency, and sample-to-answer time; analytical limits of detection should be secondary.

Occupational COVID-19 risk to dental staff working in a public dental unit in the outbreak epicenter

OBJECTIVE

The management of the COVID-19 outbreak occurred in Lombardy (Italy) implied that non-COVID-19 health care was remodeled, limiting adequate resources in non-hospital public dental healthcare settings. This situation offered the opportunity to investigate the occupational COVID-19 risk to dental staff in public non-hospital dental units.

METHODS

An infection control protocol was designed for dental health care in the Territorial Health and Social Services Authority (ASST) "Melegnano and Martesana" (Milan). Since specific guidance from central authorities was lacking, information was gathered from international public health organizations. The probability to visit asymptomatic COVID-19-infected patients was estimated, and the occupational risk to dental staff was calculated.

RESULTS

The probability to visit asymptomatic patients passed from 1.2% (95% confidence interval -95 CI, 0.6%-2.5%) in the first period (20 February-15 March 2020) to 11.1% (95 CI, 5.8%-23.6%) in the second period (16 March-30 April). Dentists and dental assistants did not develop COVID-19, while one nurse did, the nature of her occupational risk was unclear, as nurses provided prevalently non-dental health care. The probabilities of developing COVID-19 per worked hour per person excluding and including this uncertain situation were 0.0% (95 CI, 0.0%-3.2%) and 0.9% (95 CI, 0.1%-4.7%).

CONCLUSION

Relatively simple infection control procedures were enough to control occupational COVID-19 risk during the outbreak.

Policy design and state capacity in the COVID-19 emergency in Italy: if you are not prepared for the (un)expected, you can be only what you already are

Italy was the first large epicentre of the COVID-19 pandemic in the Western world. Since the country has not had any serious experience with this kind of disease in recent decades, its response has been indicative of a first reaction to an (un)known and (un)expected event. At the same time, the Italian experience is an emblematic case of how a lack of specific preparedness measures drives a country to deal with this kind of crisis through a process in which the existing characteristics of the policy and political system, with all their pros and cons, prevail. This means that the existing country characteristics that affects policy design, state capacity, institutional arrangements and political games forge the process and content of the response. Based on this observation, this paper analyses the policy dynamics of the first four months of management of the COVID-19 outbreak in Italy, focusing on how the health and economic responses were designed and implemented.

SARS-CoV-2 and cancer: Are they really partners in crime?

The outbreak of the SARS-CoV-2 pandemic has overwhelmed health care systems in many countries. The clinical presentation of the SARS-CoV-2 varies between a subclinical or flu-like syndrome to that of severe pneumonia with multi-organ failure and death. Initial reports have suggested that cancer patients may have a higher susceptibility to get infected by the SARS-CoV-2 virus but current evidence remains poor as it is biased by important confounders. Patients with ongoing or recent cancer treatment for advanced active disease, metastatic solid tumors and hematological malignancies are at higher risk of developing severe COVID-19 respiratory disease that requires hospitalization and have a poorer disease outcome compared to individuals without cancer. However it is not clear whether these are independent risk factors, or mainly driven by male gender, age, obesity, performance status, uncontrolled diabetes, cardiovascular disease and various other medical conditions. These often have a greater influence on the probability to die due to SARS-CoV-2 then cancer. Delayed diagnosis and suboptimal cancer management due to the pandemic results in disease upstaging and has considerable impact cancer on specific death rates. Surgery during the peak of the pandemic seems to increase mortality, but there is no convincing evidence that adjuvant systemic cancer therapy and radiotherapy are contraindicated, implicating that cancer treatment can be provided safely after individual risk/benefit assessment and some adaptive measures. Underlying immunosuppression, elevated cytokine levels, altered expression of the angiotensin converting enzyme (ACE-2) and TMPRSS2, and a prothrombotic status may fuel the effects of a SARS-CoV-2 in some cancer patients, but have the potential to be used as biomarkers for severe disease and therapeutic targets. The rapidly expanding literature on COVID-19 should be interpreted with care as it is often hampered by methodological and statistical flaws.

Universal PCR and antibody testing demonstrate little to no transmission of SARS-CoV-2 in a rural community

BACKGROUND

The absence of systematic surveillance for SARS-CoV-2 has curtailed accurate appraisal of transmission intensity. Our objective was to perform case detection of an entire rural community to quantify SARS-CoV-2 transmission using PCR and antibody testing.

METHODS

We conducted a cross-sectional survey of the prevalence and cumulative incidence of SARS-CoV-2 infection in the rural town of Bolinas, California (population 1,620), four weeks following shelter-in-place orders. Residents and county essential workers were tested between April 20th-24th, 2020. Prevalence by PCR and seroprevalence combining data from two forms of antibody testing were performed in parallel (Abbott ARCHITECT IgG to nucleocapsid protein and in-house IgG ELISA to the receptor binding domain).

RESULTS

Of 1,891 participants, 1,312 were confirmed Bolinas residents (>80% community ascertainment). Zero participants were PCR positive. Assuming 80% sensitivity, it would have been unlikely to observe these results (p<0.05) if there were >3 active infections in the community. Based on antibody results, estimated prevalence of prior infection was 0.16% (95% CrI: 0.02%, 0.46%). Seroprevalence estimates using only one of the two tests would have been higher, with greater uncertainty. The positive predictive value (PPV) of a positive result on both tests was 99.11% (95% CrI: 95.75%, 99.94%), compared to PPV 44.19%-63.32% (95% CrI range 3.25%-98.64%) if only one test was utilized.

CONCLUSIONS

Four weeks following shelter-in-place, active and prior SARS-CoV-2 infection in a rural Northern California community was extremely rare. In this low prevalence setting, use of two antibody tests increased the PPV and precision of seroprevalence estimates.

Prevalence of Asymptomatic SARS-CoV-2 Infection in Children and Adults in Marion County, Indiana

BACKGROUND AND OBJECTIVES

Two community studies outside the US showed asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in adults, but not in children <10 years of age. In this study, we assessed the prevalence of asymptomatic SARS-CoV-2 infection in children and adults in Marion County, Indiana.

METHODS

Individuals living in Marion County with no symptoms of coronavirus 2019 disease (COVID-19) within seven days of enrollment were eligible for this cross-sectional household study. Study kits were delivered to the participant's residence for self-swabbing, picked up by the study team, and tested by polymerase chain reaction (PCR) for SAR-CoV-2 infection.

RESULTS

Five hundred eleven nasal swabs were collected from 119 children and 392 adults ≥18 years of age. One participant (seven years of age) tested positive, for an overall study prevalence of 0.2% (95% CI 0, 0.6%). The participant had no known contact with a person with SARS-CoV-2 infection, and five family members tested negative for infection. The child and family members all tested negative for infection 10 and 20 days after the first test, and none developed symptoms of COVID-19 for 20 days after testing.

CONCLUSIONS

Asymptomatic SARS-CoV-2 infection can occur in children <10 years with no known COVID-19 exposure. Large cohort studies should be conducted to determine prevalence of asymptomatic infection and risk of transmission from asymptomatic infection in children and adults over time.

Inferred duration of infectious period of SARS-CoV-2: rapid scoping review and analysis of available evidence for asymptomatic and symptomatic COVID-19 cases

OBJECTIVES

Our objective was to review the literature on the inferred duration of the infectious period of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, and provide an overview of the variation depending on the methodological approach.

DESIGN

Rapid scoping review. Literature review with fixed search terms, up to 1 April 2020. Central tendency and variation of the parameter estimates for infectious period in (A) asymptomatic and (B) symptomatic cases from (1) virological studies (repeated testing), (2) tracing studies and (3) modelling studies were gathered. Narrative review of viral dynamics.

INFORMATION SOURCES

Search strategies developed and the following searched: PubMed, Google Scholar, MedRxiv and BioRxiv. Additionally, the Health Information Quality Authority (Ireland) viral load synthesis was used, which screened literature from PubMed, Embase, ScienceDirect, NHS evidence, Cochrane, medRxiv and bioRxiv, and HRB open databases.

RESULTS

There was substantial variation in the estimates, and how infectious period was inferred. One study provided approximate median infectious period for asymptomatic cases of 6.5-9.5 days. Median presymptomatic infectious period across studies varied over <1-4 days. Estimated mean time from symptom onset to two negative RT-PCR tests was 13.4 days (95% CI 10.9 to 15.8) but was shorter when studies included children or less severe cases. Estimated mean duration from symptom onset to hospital discharge or death (potential maximal infectious period) was 18.1 days (95% CI 15.1 to 21.0); time to discharge was on average 4 days shorter than time to death. Viral dynamic data and model infectious parameters were often shorter than repeated diagnostic data.

CONCLUSIONS

There are limitations of inferring infectiousness from repeated diagnosis, viral loads and viral replication data alone and also potential patient recall bias relevant to estimating exposure and symptom onset times. Despite this, available data provide a preliminary evidence base to inform models of central tendency for key parameters and variation for exploring parameter space and sensitivity analysis.

Inferred duration of infectious period of SARS-CoV-2: rapid scoping review and analysis of available evidence for asymptomatic and symptomatic COVID-19 cases

OBJECTIVES

Our objective was to review the literature on the inferred duration of the infectious period of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, and provide an overview of the variation depending on the methodological approach.

DESIGN

Rapid scoping review. Literature review with fixed search terms, up to 1 April 2020. Central tendency and variation of the parameter estimates for infectious period in (A) asymptomatic and (B) symptomatic cases from (1) virological studies (repeated testing), (2) tracing studies and (3) modelling studies were gathered. Narrative review of viral dynamics.

INFORMATION SOURCES

Search strategies developed and the following searched: PubMed, Google Scholar, MedRxiv and BioRxiv. Additionally, the Health Information Quality Authority (Ireland) viral load synthesis was used, which screened literature from PubMed, Embase, ScienceDirect, NHS evidence, Cochrane, medRxiv and bioRxiv, and HRB open databases.

RESULTS

There was substantial variation in the estimates, and how infectious period was inferred. One study provided approximate median infectious period for asymptomatic cases of 6.5-9.5 days. Median presymptomatic infectious period across studies varied over <1-4 days. Estimated mean time from symptom onset to two negative RT-PCR tests was 13.4 days (95% CI 10.9 to 15.8) but was shorter when studies included children or less severe cases. Estimated mean duration from symptom onset to hospital discharge or death (potential maximal infectious period) was 18.1 days (95% CI 15.1 to 21.0); time to discharge was on average 4 days shorter than time to death. Viral dynamic data and model infectious parameters were often shorter than repeated diagnostic data.

CONCLUSIONS

There are limitations of inferring infectiousness from repeated diagnosis, viral loads and viral replication data alone and also potential patient recall bias relevant to estimating exposure and symptom onset times. Despite this, available data provide a preliminary evidence base to inform models of central tendency for key parameters and variation for exploring parameter space and sensitivity analysis.

[Epidemiology of SARS-CoV-2 infection and COVID-19]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new β‑Coronavirus that was first detected in 2019 in Wuhan, China. In the ensuing months it has been transmitted worldwide. Here the authors present the current knowledge on the epidemiology of this virus. SARS-CoV‑2 replicates mainly in the upper and lower respiratory tract and is primarily transmitted by droplets from asymptomatic and symptomatic infected subjects. The estimate for the basic reproduction number (R) is currently between 2 and 3, while the incubation period is 6 (median, range 2-14) days. Although most infections are uncomplicated, 5-10% of cases develop pneumonia, which can lead to hospitalization, respiratory failure and multiorgan failure. Risk factors for a complicated disease course include age, hypertension, chronic cardiovascular and pulmonary disease and immunodeficiency. The overall case fatality rate is 1.4%, with the rate rising in the sixth decade of life. Nosocomial and infections in medical personnel have been reported. Drastic reductions in social contact have been implemented in many countries with outbreaks of SARS-CoV‑2, leading to rapid reductions in R. Which of the measures have been effective is still unknown.

On the effect of age on the transmission of SARS-CoV-2 in households, schools and the community

BACKGROUND

There is limited information on the effect of age on the transmission of SARS-CoV-2 infection in different settings, including primary, secondary and high schools, households, and the whole community. We undertook a literature review of published studies/data on detection of SARS-CoV-2 infection in contacts of COVID-19 cases, as well as serological studies, and studies of infections in the school setting to examine those issues.

RESULTS

Our literature review presents evidence for significantly lower susceptibility to infection for children aged under 10 years compared to adults given the same exposure, for elevated susceptibility to infection in adults aged over 60y compared to younger/middle aged adults, and for the risk of SARS-CoV-2 infection associated with sleeping close to an infected individual. Published serological studies also suggest that younger adults (particularly those aged under 35y) often have high cumulative rates of SARS-CoV-2 infection in the community. Additionally, there is some evidence of robust spread of SARS-CoV-2 in secondary/high schools, and there appears to be more limited spread in primary schools. Some countries with relatively large class sizes in primary schools (e.g. Chile and Israel) reported sizeable outbreaks in some of those schools, though routes of transmission of infection to both students and staff are not clear from current reports.

CONCLUSIONS

Opening secondary/high schools is likely to contribute to the spread of SARS-CoV-2, and, if implemented, it should require both lower levels of community transmission and greater safeguards to reduce transmission. Compared to secondary/high schools, opening primary schools and daycare facilities may have a more limited effect on the spread of SARS-CoV-2 in the community, particularly under smaller class sizes and in the presence of mitigation measures. Efforts to avoid crowding in the classroom and other mitigation measures should be implemented, to the extent possible, when opening primary schools. Efforts should be undertaken to diminish the mixing in younger adults to mitigate the spread of the epidemic in the whole community.

Modeling strict age-targeted mitigation strategies for COVID-19

We use a simple SIR-like epidemic model integrating known age-contact patterns for the United States to model the effect of age-targeted mitigation strategies for a COVID-19-like epidemic. We find that, among strategies which end with population immunity, strict age-targeted mitigation strategies have the potential to greatly reduce mortalities and ICU utilization for natural parameter choices.

Extensive Testing May Reduce COVID-19 Mortality: A Lesson From Northern Italy

The effects of different COVID-19 swab testing policies in Italy need investigation. We examined the relationship between the number of COVID-19 swab tests (per 10,000 population) performed from February 24 through March 27 and 7-day lagged COVID-19 mortality (per 10,000 population) in four regions of northern Italy. Lombardy, Piedmont, and initially, also Emilia-Romagna, which followed recommendations for limiting swab testing to symptomatic subjects requiring hospitalization, had a much steeper increase in mortality with increasing number of tests performed than Veneto, which applied a policy of broader testing. The relationship between tests performed and mortality declined in Emilia-Romagna in coincidence with a substantial increase in the number of tests performed on March 18. When the cumulative number of tests performed was regressed linearly toward lagged mortality in Lombardy and Veneto, the slope of the regression was 133 in Veneto and 10.4 tests per one death in Lombardy. These findings suggest that the strategy adopted in Veneto, similar to that in South Korea, was effective in containing COVID-19 epidemics and should be applied in other regions of Italy and countries in Europe.

From the index case to global spread: the global mobility based modelling of the COVID-19 pandemic implies higher infection rate and lower detection ratio than current estimates

BACKGROUND

Since the outbreak of the COVID-19 pandemic, multiple efforts of modelling of the geo-temporal transmissibility of the virus have been undertaken, but none describes the pandemic spread at the global level. The aim of this research is to provide a high-resolution global model of the pandemic that overcomes the problem of biased country-level data on the number of infected cases. To achieve this we propose a novel SIR-type metapopulation transmission model and a set of analytically derived model parameters. We used them to perform a simulation of the disease spread with help of the Global Epidemic and Mobility (GLEAM) framework embedding actual population densities, commute patterns and long-range travel networks. The simulation starts on 17 November 2019 with the index case (presymptomatic, yet infectious) in Wuhan, China, and results in an accurate prediction of the number of diagnosed cases after 154 days in multiple countries across five continents. In addition, the model outcome shows high compliance with the results of a random screening test conducted on pregnant women in the New York area.

METHODS

We have built a modified SIR metapopulation transmission model and parameterized it analytically either by setting the values of the parameters based on the literature, or by assuming their plausible values. We compared our results with the number of diagnosed cases in twenty selected countries, ones which provide reliable statistics but differ substantially in terms of strength and speed of undertaken Non-Drug Interventions. The obtained 95% confidence intervals for the predictions are in agreement with the empirical data.

RESULTS

The parameters that successfully model the pandemic are: the basic reproduction number R 0, 4.4; a latent non-infectious period of 1.1. days followed by 4.6 days of the presymptomatic infectious period; the probability of developing severe symptoms, 0.01; the probability of being diagnosed when presenting severe symptoms of 0.6; the probability of diagnosis for cases with mild symptoms or asymptomatic, 0.001.

DISCUSSION

Parameters that successfully reproduce the observed number of cases indicate that both R 0 and the prevalence of the virus might be underestimated. This is in concordance with the newest research on undocumented COVID-19 cases. Consequently, the actual mortality rate is putatively lower than estimated. Confirmation of the pandemic characteristic by further refinement of the model and screening tests is crucial for developing an effective strategy for the global epidemiological crisis.

Potential Novel Role of COVID-19 in Alzheimer's Disease and Preventative Mitigation Strategies

There are a number of potential implications for the field of Alzheimer's disease (AD) stemming from the global spread of SARS-CoV-2. Neuroinflammation is known to be a prominent feature of neurodegeneration and plays a major role in AD pathology. Immune response and excessive inflammation in COVID-19 may also accelerate the progression of brain inflammatory neurodegeneration, and elderly individuals are more susceptible to severe outcomes after SARS-CoV-2 infection. Individuals with type 2 diabetes (T2D) are at an increased risk for AD as well as severe outcomes after SARS-CoV-2 infection. Genetic and socioeconomic factors influencing the rates of T2D, AD, and COVID-19 severity may create an exceptionally high-risk profile for certain demographics such as African Americans and Hispanic Americans. Type I interferon response plays an important role in both host response to viral infection, as well as AD pathology and may be a sensible therapeutic target in both AD and COVID-19.

Chopping the tail: how preventing superspreading can help to maintain COVID-19 control

Disease transmission is notoriously heterogeneous, and SARS-CoV-2 is no exception. A skewed distribution where few individuals or events are responsible for the majority of transmission can result in explosive, superspreading events, which produce rapid and volatile epidemic dynamics, especially early or late in epidemics. Anticipating and preventing superspreading events can produce large reductions in overall transmission rates. Here, we present a compartmental (SEIR) epidemiological model framework for estimating transmission parameters from multiple imperfectly observed data streams, including reported cases, deaths, and mobile phone-based mobility that incorporates individual-level heterogeneity in transmission using previous estimates for SARS-CoV-1 and SARS-CoV-2. We parameterize the model for COVID-19 epidemic dynamics by estimating a time-varying transmission rate that incorporates the impact of non-pharmaceutical intervention strategies that change over time, in five epidemiologically distinct settings---Los Angeles and Santa Clara Counties, California; Seattle (King County), Washington; Atlanta (Dekalb and Fulton Counties), Georgia; and Miami (Miami-Dade County), Florida. We find the effective reproduction number R E dropped below 1 rapidly following social distancing orders in mid-March, 2020 and remained there into June in Santa Clara County and Seattle, but climbed above 1 in late May in Los Angeles, Miami, and Atlanta, and has trended upward in all locations since April. With the fitted model, we ask: how does truncating the tail of the individual-level transmission rate distribution affect epidemic dynamics and control? We find interventions that truncate the transmission rate distribution while partially relaxing social distancing are broadly effective, with impacts on epidemic growth on par with the strongest population-wide social distancing observed in April, 2020. Given that social distancing interventions will be needed to maintain epidemic control until a vaccine becomes widely available, "chopping off the tail" to reduce the probability of superspreading events presents a promising option to alleviate the need for extreme general social distancing.

[Addendum to S3-Guidelines Crohn's disease and ulcerative colitis: Management of Patients with Inflammatory Bowel Disease in the COVID-19 Pandemic - open questions and answers]

Die COVID-19-Pandemie ist ein weltweiter Ausbruch von neu aufgetretenen Infektionen mit dem SARS-CoV-2-Virus, von denen weltweit derzeit mehr als 10.670.000 Menschen erkrankt sind bzw. waren. In Deutschland leiden ca. 450.000 Patienten an einer chronisch entzündlichen Darmerkrankung; diese Patienten benötigen in der Regel eine kontinuierliche und kompetente Betreuung. Vor dem Hintergrund eines rasch zunehmenden Wissenszuwachses haben 68 Experten, die die derzeit gültigen Leitlinien der DGVS zum Morbus Crohn und zur Colitis ulcerosa erstellt haben, im Rahmen einer virtuellen Konferenz aktuelle und praxisnahe Empfehlungen formuliert, um die Versorgung von CED-Patienten zu verbessern. Diese adressieren das Infektionsrisiko einschließlich des Risikos für besondere Gruppen, den möglichen Verlauf der Erkrankung und die Konsequenzen für die medikamentöse und die operative Therapie der Grunderkrankung sowie allgemeine Maßnahmen zur Infektionsprävention und adjuvante Präventions- und Therapiemöglichkeiten.

Evaluation of Aircraft Boarding Scenarios Considering Reduced Transmissions Risks

Air travel appears as particularly hazardous in a pandemic situation, since infected people can travel worldwide and could cause new breakouts in remote locations. The confined space conditions in the aircraft cabin necessitate a small physical distance between passengers and hence may boost virus transmissions. In our contribution, we implemented a transmission model in a virtual aircraft environment to evaluate the individual interactions between passengers during aircraft boarding and deboarding. Since no data for the transmission is currently available, we reasonably calibrated our model using a sample case from 2003. The simulation results show that standard boarding procedures create a substantial number of possible transmissions if a contagious passenger is present. The introduction of physical distances between passengers decreases the number of possible transmissions by approx. 75% for random boarding sequences, and could further decreased by more strict reduction of hand luggage items (less time for storage, compartment space is always available). If a second door is used for boarding and deboarding, the standard boarding times could be reached. Individual boarding strategies (by seat) could reduce the transmission potential to a minimum, but demand for complex pre-sorting of passengers. Our results also exhibit that deboarding consists of the highest transmission potential and only minor benefits from distance rules and hand luggage regulations.

Pediatric COVID-19 Disease: A Review of the Recent Literature

The first pediatric coronavirus disease 2019 (COVID-19) case was confirmed in Shenzhen, China on January 20, 2020. At the beginning of the outbreak, COVID-19 pneumonia was more common in adults than in children and adolescents, and the rate of confirmed pediatric cases was relatively lower. However, as screening tests and pathogen detection campaigns were initiated in more regions as the outbreak spread, the number of pediatric infection cases increased significantly. Currently, studies on pediatric COVID-19 are limited in the literature to case reports and case series, and a few epidemiological studies. COVID-19 has distinct characteristics in the pediatric population compared to adults; therefore, we need to better understand the characteristics of this disease in children. Discovering the characteristics of the pediatric COVID-19 disease is important for contributing to the diagnosis and treatment of the disease in this population. In this review, clinical characteristics, epidemiology, diagnosis, and management of pediatric COVID-19 pneumonia based on the recent literature are discussed. [Pediatr Ann. 2020;49(7):e319-e325.].

[Management of diagnostic procedures and treatment of sleep related breathing disorders in the context of the coronavirus pandemic]

Bei der Erbringung schlafmedizinischer Leistungen im Zusammenhang mit der Corona-Pandemie sind besondere Aspekte zu berücksichtigen. Trotz aller vorbeugender Maßnahmen muss aufgrund der hohen Dunkelziffer mit SARS-CoV2-Kontakten im Schlaflabor gerechnet und entsprechende Vorkehrungen getroffen werden. Die Fortführung bzw. Wiederaufnahme schlafmedizinischer Leistungen unter den gebotenen Hygienemaßnahmen ist dennoch dringend anzustreben zur Vermeidung medizinischer und psychosozialer Komplikationen. Es gibt keine gesicherten Hinweise für eine Verschlechterung der COVID-19 durch eine CPAP-Therapie. Grundsätzlich kann die Anwendung einer Überdrucktherapie über verschiedene Maskensysteme mit der Bildung einer infektiösen Aerosolwolke einhergehen. Bei bestätigter Infektion mit SARS-CoV-2 sollte im ambulanten Umfeld eine vorbestehende Maskentherapie unter Einhaltung der Vorgaben des RKI zur häuslichen Isolierung fortgeführt werden, da eine Therapiebeendigung mit einer zusätzlichen kardiopulmonalen Belastung durch die unbehandelte schlafbezogene Atmungsstörung einhergeht. Mit geeigneter persönlicher Schutzausrüstung (Augenschutz, FFP2/FFP3-Maske, Kittel) kann eine PAP-Therapie nach jetzigem Kenntnisstand vom Personal ohne erhöhtes Infektionsrisiko durchgeführt werden.

Dieses gemeinsame Positionspapier der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin (DGP) und der Deutschen Gesellschaft für Schlafmedizin (DGSM) beinhaltet konkrete Empfehlungen zur Durchführung schlafmedizinischer Diagnostik und Therapie im Umfeld der Corona-Pandemie.

COVID-19 projections for reopening Connecticut

Key Points

Closure of schools and the statewide “Stay Safe, Stay Home” order have effectively reduced COVID-19 transmission in Connecticut, with model projections estimating incidence at about 1,300 new infections per day.

If close interpersonal contact increases quickly in Connecticut following reopening on May 20, the state is at risk of a substantial increase of COVID-19 infections, hospitalizations, and deaths by late Summer 2020.

Real-time metrics including case counts, hospitalizations, and deaths may fail to provide enough advance warning to avoid resurgence.

Substantial uncertainty remains in our knowledge of cumulative COVID-19 incidence, the proportion of infected individuals who are asymptomatic, infectiousness of children, the effects of testing and contact tracing on isolation of infected individuals, and how contact patterns may change following reopening.

COVID-19 and the re-opening of schools: a policy maker's dilemma

The epidemic of coronavirus disease 2019 (COVID-19) broke out in Wuhan, China, in December 2019 and rapidly spread across the world. In order to counter this epidemic, several countries put in place different restrictive measures, such as the school’s closure and a total lockdown. However, as the knowledge on the disease progresses, clinical evidence showed that children mainly have asymptomatic or mild disease and it has been suggested that they are also less likely to spread the virus. Moreover, the lockdown and the school closure could have negative consequences on children, affecting their social life, their education and their mental health. As many countries have already entered or are planning a phase of gradual lifting of the containment measures of social distancing, it seems plausible that the re-opening of nursery schools and primary schools could be considered a policy to be implemented at an early stage of recovery efforts, putting in place measures to do it safely, such as the maintenance of social distance, the reorganisation of classes into smaller groups, the provision of adequate sanitization of spaces, furniture and toys, the prompt identification of cases in the school environment and their tracing. Therefore, policy makers have the task of balancing pros and cons of the school re-opening strategy, taking into account psychological, educational and social consequences for children and their families. Another issue to be considered is represented by socio-economic disparities and inequalities which could be amplified by school’s closure.

Containment of future waves of COVID-19: simulating the impact of different policies and testing capacities for contact tracing, testing, and isolation

We used multi-agent simulations to estimate the testing capacity required to find and isolate a number of infections sufficient to break the chain of transmission of SARS-CoV-2. Depending on the mitigation policies in place, a daily capacity between 0.7 to 3.6 tests per thousand was required to contain the disease. However, if contact tracing and testing efficacy dropped below 60% (e.g. due to false negatives or reduced tracing capability), the number of infections kept growing exponentially, irrespective of any testing capacity. Under these conditions, the population's geographical distribution and travel behaviour could inform sampling policies to aid a successful containment.

What settings have been linked to SARS-CoV-2 transmission clusters?

Background: Concern about the health impact of novel coronavirus SARS-CoV-2 has resulted in widespread enforced reductions in people's movement ("lockdowns"). However, there are increasing concerns about the severe economic and wider societal consequences of these measures. Some countries have begun to lift some of the rules on physical distancing in a stepwise manner, with differences in what these "exit strategies" entail and their timeframes. The aim of this work was to inform such exit strategies by exploring the types of indoor and outdoor settings where transmission of SARS-CoV-2 has been reported to occur and result in clusters of cases. Identifying potential settings that result in transmission clusters allows these to be kept under close surveillance and/or to remain closed as part of strategies that aim to avoid a resurgence in transmission following the lifting of lockdown measures. Methods: We performed a systematic review of available literature and media reports to find settings reported in peer reviewed articles and media with these characteristics. These sources are curated and made available in an editable online database. Results: We found many examples of SARS-CoV-2 clusters linked to a wide range of mostly indoor settings. Few reports came from schools, many from households, and an increasing number were reported in hospitals and elderly care settings across Europe. Conclusions: We identified possible places that are linked to clusters of COVID-19 cases and could be closely monitored and/or remain closed in the first instance following the progressive removal of lockdown restrictions. However, in part due to the limits in surveillance capacities in many settings, the gathering of information such as cluster sizes and attack rates is limited in several ways: inherent recall bias, biased media reporting and missing data.

The role of children in transmission of SARS-CoV-2: A rapid review

BACKGROUND

Understanding the role of children in the transmission of SARS-CoV-2 is urgently required given its policy implications in relation to the reopening of schools and intergenerational contacts.

METHODS

We conducted a rapid review of studies that investigated the role of children in the transmission of SARS-CoV-2. We synthesized evidence for four categories: 1) studies reporting documented cases of SARS-CoV-2 transmission by infected children; 2) studies presenting indirect evidence on the potential of SARS-CoV-2 transmission by (both symptomatic and asymptomatic) children; 3) studies reporting cluster outbreaks of COVID-19 in schools; 4) studies estimating the proportions of children infected by SARS-CoV-2, and reported results narratively.

RESULTS

A total of 16 unique studies were included for narrative synthesis. There is limited evidence detailing transmission of SARS-CoV-2 from infected children. We found two studies that reported a 3-month-old whose parents developed symptomatic COVID-19 seven days after caring for the infant and two children who may have contracted COVID-19 from the initial cases at a school in New South Wales. In addition, we identified six studies presenting indirect evidence on the potential for SARS-CoV-2 transmission by children, three of which found prolonged virus shedding in stools. There is little data on the transmission of SARS-CoV-2 in schools. We identified only two studies reporting outbreaks of COVID-19 in school settings and one case report of a child attending classes but not infecting any other pupils or staff. Lastly, we identified six studies estimating the proportion of children infected; data from population-based studies in Iceland, Italy, South Korea, Netherlands, California and a hospital-based study in the UK suggest children may be less likely to be infected.

CONCLUSIONS

Preliminary results from population-based and school-based studies suggest that children may be less frequently infected or infect others, however current evidence is limited. Prolonged faecal shedding observed in studies highlights the potentially increased risk of faeco-oral transmission in children. Further seroprevalence studies (powered adequately for the paediatric population) are urgently required to establish whether children are in fact less likely to be infected compared to adults.

NOTE

We plan to update this rapid review as new data becomes available. These updates are available at https://www.ed.ac.uk/usher/uncover/completed-uncover-reviews.

Weekly COVID-19 testing with household quarantine and contact tracing is feasible and would probably end the epidemic

The COVID-19 epidemic can probably be ended and normal life restored, perhaps quite quickly, by weekly SARS-CoV-2 RNA testing together with household quarantine and systematic contact tracing. Isolated outbreaks could then be contained by contact tracing, supplemented if necessary by temporary local reintroduction of population testing or lockdown. Leading public health experts have recommended that this should be tried in a demonstration project in which a medium-sized city introduces weekly testing and lifts lockdown completely. The idea was not considered by the groups whose predictions have guided UK policy, so we have examined the statistical case for such a study. The combination of regular testing with strict household quarantine, which was not analysed in their models, has remarkable power to reduce transmission to the community from other household members as well as providing earlier diagnosis and facilitating rapid contact tracing.

Italian Public Health Response to the COVID-19 Pandemic: Case Report from the Field, Insights and Challenges for the Department of Prevention

: The coronavirus disease (COVID-19) outbreak is rapidly progressing globally, and Italy, as one of the main pandemic hotspots, may provide some hard lessons for other countries. In this paper, we summarize the current organizational capacity and provide a pragmatic and narrative account of strategies and activities implemented by the Department of Prevention (Dipartimento di Prevenzione)-the regional entity of the Local Health Authority of the Italian National Health Service in charge of public health-since the beginning of the outbreak. We conduct a preliminary analysis of general strengths, weaknesses, opportunities, and threats (SWOT) of the response strategies from a local perspective. Furthermore, we provide firsthand insights on future directions and priorities to manage this unprecedented pandemic. Our case report gives a qualitative view of the healthcare response, based on the experience of frontline professionals, with the aim to generate hypotheses about factors which may promote or hinder the prevention and management of a pandemic locally. We highlight the importance of a public health approach for responding to COVID-19 and reshaping healthcare systems.

Severe air pollution links to higher mortality in COVID-19 patients: The "double-hit" hypothesis

OBJECTIVES

In areas of SARS-CoV-2 outbreak worldwide mean air pollutants concentrations vastly exceed the maximum limits. Chronic exposure to air pollutants have been associated with lung ACE-2 over-expression which is known to be the main receptor for SARS-CoV-2. The aim of this study was to analyse the relationship between air pollutants concentration (PM 2.5 and NO2) and COVID-19 outbreak, in terms of transmission, number of patients, severity of presentation and number of deaths.

METHODS

COVID-19 cases, ICU admissions and mortality rate were correlated with severity of air pollution in the Italian regions.

RESULTS

The highest number of COVID-19 cases were recorded in the most polluted regions with patients presenting with more severe forms of the disease requiring ICU admission. In these regions, mortality was two-fold higher than the other regions.

CONCLUSIONS

From the data available we propose a "double-hit hypothesis": chronic exposure to PM 2.5 causes alveolar ACE-2 receptor overexpression. This may increase viral load in patients exposed to pollutants in turn depleting ACE-2 receptors and impairing host defences. High atmospheric NO2 may provide a second hit causing a severe form of SARS-CoV-2 in ACE-2 depleted lungs resulting in a worse outcome.

The COVID-19 Infection in Italy: A Statistical Study of an Abnormally Severe Disease

We statistically investigate the Coronavirus Disease 19 (COVID-19) pandemic, which became particularly invasive in Italy in March 2020. We show that the high apparent lethality or case fatality ratio (CFR) observed in Italy, as compared with other countries, is likely biased by a strong underestimation of the number of infection cases. To give a more realistic estimate of the lethality of COVID-19, we use the actual (March 2020) estimates of the infection fatality ratio (IFR) of the pandemic based on the minimum observed CFR and analyze data obtained from the Diamond Princess cruise ship, a good representation of a "laboratory" case-study from an isolated system in which all the people have been tested. From such analyses, we derive more realistic estimates of the real extent of the infection as well as more accurate indicators of how fast the infection propagates. We then isolate the dominant factors causing the abnormal severity of the disease in Italy. Finally, we use the death count-the only data estimated to be reliable enough-to predict the total number of people infected and the interval of time when the infection in Italy could end.

The COVID-19 Infection in Italy: A Statistical Study of an Abnormally Severe Disease

We statistically investigate the Coronavirus Disease 19 (COVID-19) pandemic, which became particularly invasive in Italy in March 2020. We show that the high apparent lethality or case fatality ratio (CFR) observed in Italy, as compared with other countries, is likely biased by a strong underestimation of the number of infection cases. To give a more realistic estimate of the lethality of COVID-19, we use the actual (March 2020) estimates of the infection fatality ratio (IFR) of the pandemic based on the minimum observed CFR and analyze data obtained from the Diamond Princess cruise ship, a good representation of a "laboratory" case-study from an isolated system in which all the people have been tested. From such analyses, we derive more realistic estimates of the real extent of the infection as well as more accurate indicators of how fast the infection propagates. We then isolate the dominant factors causing the abnormal severity of the disease in Italy. Finally, we use the death count-the only data estimated to be reliable enough-to predict the total number of people infected and the interval of time when the infection in Italy could end.

The impact of long-term non-pharmaceutical interventions on COVID-19 epidemic dynamics and control

Non-pharmaceutical interventions to combat COVID-19 transmission have worked to slow the spread of the epidemic but can have high socio-economic costs. It is critical we understand the efficacy of non-pharmaceutical interventions to choose a safe exit strategy. Many current models are not suitable for assessing exit strategies because they do not account for epidemic resurgence when social distancing ends prematurely (e.g., statistical curve fits) nor permit scenario exploration in specific locations. We developed an SEIR-type mechanistic epidemiological model of COVID-19 dynamics to explore temporally variable non-pharmaceutical interventions. We provide an interactive tool and code to estimate the transmission parameter, β, and the effective reproduction number, R eff . We fit the model to Santa Clara County, California, where an early epidemic start date and early shelter-in-place orders could provide a model for other regions. As of April 22, 2020, we estimate an R eff of 0.982 (95% CI: 0.849 - 1.107) in Santa Clara County. After June 1 (the end-date for Santa Clara County shelter-in-place as of April 27), we estimate a shift to partial social distancing, combined with rigorous testing and isolation of symptomatic individuals, is a viable alternative to indefinitely maintaining shelter-in-place. We also estimate that if Santa Clara County had waited one week longer before issuing shelter-in-place orders, 95 additional people would have died by April 22 (95% CI: 7 - 283). Given early life-saving shelter-in-place orders in Santa Clara County, longer-term moderate social distancing and testing and isolation of symptomatic individuals have the potential to contain the size and toll of the COVID-19 pandemic in Santa Clara County, and may be effective in other locations.

What settings have been linked to SARS-CoV-2 transmission clusters?

Background: Concern about the health impact of novel coronavirus SARS-CoV-2 has resulted in widespread enforced reductions in people's movement ("lockdowns"). However, there are increasing concerns about the severe economic and wider societal consequences of these measures. Some countries have begun to lift some of the rules on physical distancing in a stepwise manner, with differences in what these "exit strategies" entail and their timeframes. The aim of this work was to inform such exit strategies by exploring the types of indoor and outdoor settings where transmission of SARS-CoV-2 has been reported to occur and result in clusters of cases. Identifying potential settings that result in transmission clusters allows these to be kept under close surveillance and/or to remain closed as part of strategies that aim to avoid a resurgence in transmission following the lifting of lockdown measures. Methods: We performed a systematic review of available literature and media reports to find settings reported in peer reviewed articles and media with these characteristics. These sources are curated and made available in an editable online database. Results: We found many examples of SARS-CoV-2 clusters linked to a wide range of mostly indoor settings. Few reports came from schools, many from households, and an increasing number were reported in hospitals and elderly care settings across Europe. Conclusions: We identified possible places that are linked to clusters of COVID-19 cases and could be closely monitored and/or remain closed in the first instance following the progressive removal of lockdown restrictions. However, in part due to the limits in surveillance capacities in many settings, the gathering of information such as cluster sizes and attack rates is limited in several ways: inherent recall bias, biased media reporting and missing data.

Modelling a pandemic with asymptomatic patients, impact of lockdown and herd immunity, with applications to SARS-CoV-2

The SARS-CoV-2 is a type of coronavirus that has caused the pandemic known as the Coronavirus Disease of 2019, or COVID-19. In traditional epidemiological models such as SEIR (Susceptible, Exposed, Infected, Removed), the exposed group E does not infect the susceptible group S. A distinguishing feature of COVID-19 is that, unlike with previous viral diseases, there is a distinct "asymptomatic" group A, which does not show any symptoms, but can nevertheless infect others, at the same rate as infected symptomatic patients. This situation is captured in a model known as SAIR (Susceptible, Asymptomatic, Infected, Removed), introduced in Robinson and Stillianakis (2013). The dynamical behavior of the SAIR model is quite different from that of the SEIR model. In this paper, we use Lyapunov theory to establish the global asymptotic stabililty of the SAIR model, both without and with vital dynamics. Then we develop compartmental SAIR models to cater to the migration of population across geographic regions, and once again establish global asymptotic stability. Next, we go beyond long-term asymptotic analysis and present methods for estimating the parameters in the SAIR model. We apply these estimation methods to data from several countries including India, and demonstrate that the predicted trajectories of the disease closely match actual data. We show that "herd immunity" (defined as the time when the number of infected persons is maximum) can be achieved when the total of infected, symptomatic and asymptomatic persons is as low as 25% of the population. Previous estimates are typically 50% or higher. We also conclude that "lockdown" as a way of greatly reducing inter-personal contact has been very effective in checking the progress of the disease.