Estimation of COVID-19 outbreak size in Italy.
About: This article is published in Lancet Infectious Diseases.The article was published on 2020-03-19 and is currently open access. It has received 138 citations till now. The article focuses on the topics: Outbreak & Betacoronavirus.
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TL;DR: This study indicates that convalescent plasma therapy is effective and specific for COVID‐19, and has a special significance for eliminating SARS‐CoV‐2 and is believed to be a promising state‐of‐the‐art therapy during CO VID‐19 pandemic crisis.
Abstract: The discovery of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the outbreak of coronavirus disease 2019 (COVID-19) are causing public health emergencies. A handful pieces of literature have summarized its clinical and radiologic features, whereas therapies for COVID-19 are rather limited. To evaluate the efficacy of convalescent plasma therapy in COVID-19 patients, we did this timely descriptive study. Six laboratory-confirmed COVID-19 patients were enrolled and received the transfusion of ABO-compatible convalescent plasma. The efficacy of this intervention was determined by the alleviation of symptoms, changes in radiologic abnormalities and laboratory tests. No obvious adverse effect observed during the treatment. Transfusion of convalescent plasma led to a resolution of ground-glass opacities and consolidation in patients #1, #2, #3, #4, and #6. In patients #1 and #5 who presented with SARS-CoV-2 in throat swab, convalescent plasma therapy elicited an elimination of the virus. Serologic analysis indicated an immediate increase in anti-SARS-CoV-2 antibody titers in patients #2 and #3, but not in patient #1. This study indicates that convalescent plasma therapy is effective and specific for COVID-19. This intervention has a special significance for eliminating SARS-CoV-2 and is believed to be a promising state-of-the-art therapy during COVID-19 pandemic crisis.
351 citations
Cites background from "Estimation of COVID-19 outbreak siz..."
...By the end of March, 2020, COVID‐19 has spread up to 199 countries and causing more than 27 000 deaths.(8) SARS‐CoV‐2 belongs to the β‐coronavirus family....
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TL;DR: There is evidence that older age and several comorbidities can affect the risk to develop severe pneumonia and possibly the need of mechanic ventilation in subjects infected with SARS‐CoV‐2.
Abstract: Background The recent SARS-CoV-2 pandemic, which has recently affected Italy since February 21, constitutes a threat to normal subjects, as the coronavirus disease-19 (COVID-19) can manifest with a broad spectrum of clinical phenotypes ranging from asymptomatic cases to pneumonia or even death. There is evidence that older age and several comorbidities can affect the risk to develop severe pneumonia and possibly the need of mechanic ventilation in subjects infected with SARS-CoV-2. Therefore, we evaluated the outcome of SARS-CoV-2 infection in patients with inborn errors of immunity (IEI) such as X-linked agammaglobulinemia (XLA). Methods When the SARS-CoV-2 epidemic has reached Italy, we have activated a surveillance protocol of patients with IEI, to perform SARS-CoV-2 search by nasopharyngeal swab in patients presenting with symptoms that could be a manifestation of COVID-19, such as fever, cough, diarrhea, or vomiting. Results We describe two patients with X-linked agammaglobulinemia (XLA) aged 34 and 26 years with complete absence of B cells from peripheral blood who developed COVID-19, as diagnosed by SARS-CoV-2 detection by nasopharyngeal swab, while receiving immunoglobulin infusions. Both patients developed interstitial pneumonia characterized by fever, cough, and anorexia and associated with elevation of CRP and ferritin, but have never required oxygen ventilation or intensive care. Conclusion Our report suggests that XLA patients might present with high risk to develop pneumonia after SARS-CoV-2 infection, but can recover from infection, suggesting that B-cell response might be important, but is not strictly required to overcome the disease. However, there is a need for larger observational studies to extend these conclusions to other patients with similar genetic immune defects.
289 citations
TL;DR: This study highlights the importance of country lockdown and self isolation in control the disease transmissibility among Italian population through data driven model analysis and suggests that nearly 35% decrement of registered cases and 66% growth of recovered cases will be possible.
Abstract: Background Till 31 March 2020, 105,792 COVID-19 cases were confirmed in Italy including 15,726 deaths which explains how worst the epidemic has affected the country. After the announcement of lockdown in Italy on 9 March 2020, situation was becoming stable since last days of March. In view of this, it is important to forecast the COVID-19 evaluation of Italy condition and the possible effects, if this lock down could continue for another 60 days. Methods COVID-19 infected patient data has extracted from the Italian Health Ministry website includes registered and recovered cases from mid February to end March. Adoption of seasonal ARIMA forecasting package with R statistical model was done. Results Predictions were done with 93.75% of accuracy for registered case models and 84.4% of accuracy for recovered case models. The forecasting of infected patients could be reach the value of 182,757, and recovered cases could be registered value of 81,635 at end of May. Conclusions This study highlights the importance of country lockdown and self isolation in control the disease transmissibility among Italian population through data driven model analysis. Our findings suggest that nearly 35% decrement of registered cases and 66% growth of recovered cases will be possible.
220 citations
TL;DR: This research content is granted for free by Elsevier to make all its COVID-19-related research that is available on the CO VID-19 resource centre immediately available in PubMed Central and other publicly funded repositories with rights for unrestricted research re-use and analyses.
218 citations
TL;DR: This study provides a national-scale analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) superspreading during the first wave of infections in Austria, a country that played a major role in initial virus transmissions in Europe.
Abstract: Superspreading events shaped the coronavirus disease 2019 (COVID-19) pandemic, and their rapid identification and containment are essential for disease control. Here, we provide a national-scale analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) superspreading during the first wave of infections in Austria, a country that played a major role in initial virus transmissions in Europe. Capitalizing on Austria's well-developed epidemiological surveillance system, we identified major SARS-CoV-2 clusters during the first wave of infections and performed deep whole-genome sequencing of more than 500 virus samples. Phylogenetic-epidemiological analysis enabled the reconstruction of superspreading events and charts a map of tourism-related viral spread originating from Austria in spring 2020. Moreover, we exploited epidemiologically well-defined clusters to quantify SARS-CoV-2 mutational dynamics, including the observation of low-frequency mutations that progressed to fixation within the infection chain. Time-resolved virus sequencing unveiled viral mutation dynamics within individuals with COVID-19, and epidemiologically validated infector-infectee pairs enabled us to determine an average transmission bottleneck size of 103 SARS-CoV-2 particles. In conclusion, this study illustrates the power of combining epidemiological analysis with deep viral genome sequencing to unravel the spread of SARS-CoV-2 and to gain fundamental insights into mutational dynamics and transmission properties.
211 citations
References
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TL;DR: Transmissibility is substantially higher than that of seasonal flu, and comparable with lower estimates of R0 obtained from previous influenza pandemics, by analyzing the outbreak in Mexico, early data on international spread, and viral genetic diversity, which makes an early assessment of transmissibility and severity.
Abstract: A novel influenza A (H1N1) virus has spread rapidly across the globe. Judging its pandemic potential is difficult with limited data, but nevertheless essential to inform appropriate health responses. By analyzing the outbreak in Mexico, early data on international spread, and viral genetic diversity, we make an early assessment of transmissibility and severity. Our estimates suggest that 23,000 (range 6000 to 32,000) individuals had been infected in Mexico by late April, giving an estimated case fatality ratio (CFR) of 0.4% (range: 0.3 to 1.8%) based on confirmed and suspected deaths reported to that time. In a community outbreak in the small community of La Gloria, Veracruz, no deaths were attributed to infection, giving an upper 95% bound on CFR of 0.6%. Thus, although substantial uncertainty remains, clinical severity appears less than that seen in the 1918 influenza pandemic but comparable with that seen in the 1957 pandemic. Clinical attack rates in children in La Gloria were twice that in adults ( /=15 years: 29%). Three different epidemiological analyses gave basic reproduction number (R0) estimates in the range of 1.4 to 1.6, whereas a genetic analysis gave a central estimate of 1.2. This range of values is consistent with 14 to 73 generations of human-to-human transmission having occurred in Mexico to late April. Transmissibility is therefore substantially higher than that of seasonal flu, and comparable with lower estimates of R0 obtained from previous influenza pandemics.
1,888 citations
TL;DR: The relationship between the strength of travel links with Iran and the ranking of destination countries on the Infectious Disease Vulnerability Index (IDVI), a validated metric that estimates the capacity of a country to respond to an infectious disease outbreak, was evaluated.
Abstract: Estimation of Coronavirus Disease 2019 (COVID-19) Burden and Potential for International Dissemination of Infection From Iran Background: The coronavirus disease 2019 (COVID-19) epidemic began in Wuhan, China, in late 2019 and continues to spread globally (1), with exported cases confirmed in 109 countries at the time of writing (2). During the interval between 19 February and 23 February 2020, Iran reported its first 43 cases, with 8 deaths. Three exported cases originating in Iran were identified, suggesting an underlying burden of disease in that country greater than that indicated by reported cases. A large epidemic in Iran could further fuel global dissemination of COVID-19. Objective: To quantify the COVID-19 outbreak size in Iran on the basis of known exported case counts and air travel links between Iran and other countries, and to anticipate where infections originating in Iran may spread next. Methods: We assessed interconnectivity between Iran and other countries by using direct and total traveler volumes and final destination cities of travelers originating in Iran in February 2019, according to data from the International Air Transport Association (accounting for 90% of global air travel, with the other 10% modeled by using market intelligence). Because exported cases were identified in United Arab Emirates (UAE), Lebanon, and Canada, we used the methods of Fraser and colleagues (3) to estimate the size of the underlying epidemic in Iran that would be needed for these cases to be observed with a reasonable probability. To estimate the time at risk for COVID-19 exposure among travelers departing Iran, we obtained data from the United Nations World Tourism Organization for the proportion of international travelers who are residents of Iran (4) and the average length of stay of tourists to Iran (5), and assumed that the Iranian outbreak began in early January 2020. We evaluated the relationship between the strength of travel links with Iran and the ranking of destination countries on the Infectious Disease Vulnerability Index (IDVI), a validated metric that estimates the capacity of a country to respond to an infectious disease outbreak. Scores range from 0 to 1, with higher scores reflecting greater capacity to manage infectious outbreaks. Findings: A total of 212 000 persons traveled from Iranian airports (Tehran, Rasht, and Arak) to international destinations in February 2019. Although Qom has reported COVID-19 cases, its international airport is still under construction. Global cities receiving the greatest number of total travelers from Iran during this period include Istanbul, Turkey (n = 46 550); Najaf, Iraq (n = 24 659); and Dubai, UAE (n = 16 340). Among the top 10 traveler-receiving cities, 4 (Najaf, Baghdad, Damascus, and Baku) are in countries with an IDVI score lower than 0.6, suggesting elevated vulnerability to infectious disease outbreaks as well as limited ability to detect cases (Figure 1). United Arab Emirates, Lebanon, and Canada ranked third, 21st, and 31st, respectively, for outbound air travel volume from Iran in February 2019. We estimated that 18 300 COVID-19 cases (95% CI, 3770 to 53 470 cases) would have had to occur in Iran, assuming an outbreak duration of 1.5 months in the country, in order to observe these 3 internationally exported cases reported at the time of writing.
114 citations
TL;DR: It is likely that Iran is currently experiencing a COVID-19 epidemic of significant size for such exportations to be occurring, and because of the high likelihood for outward dissemination of the epidemic to neighbouring countries with lower capacity to respond to infectious diseases epidemics.
Abstract: The Coronavirus Disease 2019 (COVID-19) epidemic began in Wuhan, China in late 2019 and continues to spread globally, with exported cases confirmed in 28 countries at the time of writing. During the interval between February 19 and 23, 2020, Iran reported its first 43 cases with eight deaths. Three exported cases originating in Iran were identified, suggesting a underlying burden of disease in that country than is indicated by reported cases. A large epidemic in Iran could further fuel global dissemination of COVID-19. We sought to estimate COVID-19 outbreak size in Iran based on known exported case counts and air travel links between Iran and other countries, and to anticipate where infections originating in Iran may spread to next. We assessed interconnectivity between Iran and other countries using using International Air Transport Association (IATA) data. We used the methods of Fraser et al. to estimate the size of the underlying epidemic that would result in cases being observed in the United Arab Emirates (UAE), Lebanon, and Canada. Time at risk estimates were based on a presumed 6 week epidemic age, and length of stay data for visitors to Iran derived from the United Nations World Tourism Organization (UNWTO). We evaluated the relationship between the strength of travel links with Iran, and destination country rankings on the Infectious Disease Vulnerability Index (IDVI), a validated metric that estimates the capacity of a country to respond to an infectious disease outbreak. Scores range between 0-1, with higher scores reflecting greater capacity to manage infectious outbreaks. UAE, Lebanon, and Canada ranked 3rd, 21st, and 31st, respectively, for outbound air travel volume from Iran in February 2019. We estimated that 18,300 (95% confidence interval: 3770 to 53,470) COVID-19 cases would have had to occur in Iran, assuming an outbreak duration of 1.5 months in the country, in order to observe these three internationally exported cases reported at the time of writing. Results were robust under varying assumptions about undiagnosed case numbers in Syria, Azerbaijan and Iraq. Even if it were assumed that all cases were identified in all countries with certainty, the "best case" outbreak size was substantial (1820, 95% CI: 380-5320 cases), and far higher than reported case counts. Given the low volumes of air travel to countries with identified cases of COVID-19 with origin in Iran (such as Canada), it is likely that Iran is currently experiencing a COVID-19 epidemic of significant size for such exportations to be occurring. This is concerning, both for public health in Iran itself, and because of the high likelihood for outward dissemination of the epidemic to neighbouring countries with lower capacity to respond to infectious diseases epidemics.
45 citations
TL;DR: Fears that travellers were starting to carry the infection from its European epicentre are confirmed as confirmed cases of covid-19 in Italy leapt by 45% to reach 322 on 25 February, and four more deaths were confirmed.
Abstract: Confirmed cases of covid-19 in Italy leapt by 45% to reach 322 on 25 February, and four more deaths were confirmed amid signs that the infection was spreading around the country and across borders.
New cases in Italy were reported in central Tuscany, the coastal region of Liguria, and Sicily in the south. Officials confirmed that the national death toll was now 11.
Authorities in Austria and Croatia also reported their first cases of covid-19 and said that the patients affected had recently travelled from Italy’s Lombardy region, confirming fears that travellers were starting to carry the infection from its European epicentre. An Italian couple from the north of Italy tested positive on the Spanish island …
41 citations