Modelling the Risk of Imported COVID-19 Infections at Maritime Ports Based on the Mobility of International-Going Ships

Maritime ports are critical logistics hubs that play an important role when preventing the transmission of COVID-19-imported infections from incoming international-going ships. This study introduces a data-driven method to dynamically model infection risks of international ports from imported COVID-19 cases. The approach is based on global Automatic Identification System (AIS) data and a spatio-temporal clustering algorithm that both automatically identifies ports and countries approached by ships and correlates them with country COVID-19 statistics and stopover dates. The infection risk of an individual ship is firstly modeled by considering the current number of COVID-19 cases of the approached countries, increase rate of the new cases, and ship capacity. The infection risk of a maritime port is mainly calculated as the aggregation of the risks of all of the ships stopovering at a specific date. This method is applied to track the risk of the imported COVID-19 of the main cruise ports worldwide. The results show that the proposed method dynamically estimates the risk level of the overseas imported COVID-19 of cruise ports and has the potential to provide valuable support to improve prevention measures and reduce the risk of imported COVID-19 cases in seaports.

The Effects of Heatwaves on Human Morbidity in Primary Care Settings: A Case-Crossover Study

Purpose: This study assesses the potential acute effects of heatwaves on human morbidities in primary care settings. Methods: We performed a time-stratified case-crossover study to assess the acute effects of heatwaves on selected morbidities in primary care settings in Flanders, Belgium, between 2000 and 2015. We used conditional logistic regression models. We assessed the effect of heatwaves on the day of the event (lag 0) and X days earlier (lags 1 to X). The associations are presented as Incidence Density Ratios (IDR). Results: We included 22,344 events. Heatwaves are associated with increased heat-related morbidities such as heat stroke IDR 3.93 [2.94–5.26] at lag 0, dehydration IDR 3.93 [2.94–5.26] at lag 1, and orthostatic hypotension IDR 2.06 [1.37–3.10] at lag 1. For cardiovascular morbidities studied, there was only an increased risk of stroke at lag 3 IDR 1.45 [1.04–2.03]. There is no significant association with myocardial ischemia/infarction or arrhythmia. Heatwaves are associated with decreased respiratory infection risk. The IDR for upper respiratory infections is 0.82 [0.78–0.87] lag 1 and lower respiratory infections (LRI) is 0.82 [0.74–0.91] at lag 1. There was no significant effect modification by age or premorbid chronic disease (diabetes, hypertesnsion). Conclusion: Heatwaves are associated with increased heat-related morbidities and decreased respiratory infection risk. The study of heatwaves’ effects in primary care settings helps evaluate the impact of heatwaves on the general population. Primary care settings might be not suitable to study acute life-threatening morbidities.

Risk of infection and appeal to public benefit increase compliance with infection control measures

To handle an infectious outbreak, the public must be informed about the infection risk and be motivated to comply with infection control measures. Perceiving the situation as threatening and seeing public benefits to complying may increase the public’s motivation to comply. The current study used a preregistered survey experiment to investigate if emphasizing high infection risk and appealing to societal benefits impacted intention to comply with infection control measures. The results show main effects of risk and of appeals to societal benefits. There was no interaction between risk scenario and motivational emphasis. The results suggest that to maximize compliance, information about disease outbreak should emphasize the individual risk of contracting the disease, and could also underline the public value of limiting infection spread. These findings can inform communication strategies during an infectious disease outbreak and help health authorities limit transmission.

Research and Development of a COVID-19 Tracking System in Order to Implement Analytical Tools to Reduce the Infection Risk

The whole world is currently focused on COVID-19, which causes considerable economic and social damage. The disease is spreading rapidly through the population, and the effort to stop the spread is entirely still failing. In our article, we want to contribute to the improvement of the situation. We propose a tracking system that would identify affected people with greater accuracy than medical staff can. The main goal was to design hardware and construct a device that would track anonymous risky contacts in areas with a highly concentrated population, such as schools, hospitals, large social events, and companies. We have chosen a 2.4 GHz proprietary protocol for contact monitoring and mutual communication of individual devices. The 2.4 GHz proprietary protocol has many advantages such as a low price and higher resistance to interference and thus offers benefits. We conducted a pilot experiment to catch bugs in the system. The device is in the form of a bracelet and captures signals from other bracelets worn at a particular location. In case of contact with an infected person, the alarm is activated. This article describes the concept of the tracking system, the design of the devices, initial tests, and plans for future use.

Experimental Methods of Investigating Airborne Indoor Virus-Transmissions Adapted to Several Ventilation Measures

This study introduces a principle, which unifies two experimental methods for airborne indoor virus-transmissions adapted to several ventilation measures. A first-time comparison of mechanical/natural ventilation and air purifiers with regard to infection risks is achieved. Effortful computational fluid dynamics demand detailed boundary conditions for accurate calculations of indoor airflows, which are often unknown. Hence a suitable, simple and generalized experimental set up for identifying the spatial and temporal infection risk for different ventilation measures is required. A trace gas method is suitable for mechanical and natural ventilation with outdoor air exchange. For an accurate assessment of air purifiers based on filtration a surrogate particle method is appropriate. The release of a controlled rate of either trace gas or particles simulates an infectious person releasing virus material. Surrounding substance concentration measurements identify the neighborhood exposure. One key aspect of the study is to prove that the requirement of concordant results of both methods is fulfilled. This is the only way to ensure that the comparison of different ventilation measures described above is reliable. Two examples (a two person office, several classrooms) show how practical both methods are and how the principle is applicable for different types and sizes of rooms.

Epidemiological Community and Differences of Transmissive Infections in Astrakhan Region

Relevance. The territory of the Astrakhan region hosts natural foci of severe infections of arbovirus etiology – Crimean-Congo hemorrhagic fever (CCHF) and Astrakhan fever (spotted fever resembling the Mediterranean spotted fever, Astrakhan spotted fever (ASF). The long-term average incidence of CCHF and ASF in the Astrakhan region is to 11 and 135 times higher, respectively, than the average incidence in the Russian Federation. Aims. To present, based on epidemiological data, a comparative characterization of transmissible infections of CCHF and ASF in the Astrakhan region. Materials & Methods. The main method of the study was epidemiological. The data for 2000−2016 of primary medical documentation Ф.058/у «Emergency notification of infectious disease, food, acute occupational poisoning, unusual reaction to vaccination», federal statistical observation Ф. 2 «Information on infectious and parasitic diseases», Ф. 357/у «Epidemiological examination card of infectious disease focus», Ф. .003/у «Medical card of inpatient patient», presented by Center of hygiene and epidemiology in Astrakhan region. For retrospective epidemiological analysis, we studied the absolute and intensive morbidity indicators (per 100 ths population), by age, professional groups, and among the urban and rural population. Based on the average long-term morbidity indicators of the population, a mapping of the territory of the Astrakhan region was carried out. The influence of natural and climatic conditions on the epidemic process of CCHF and ASF was assessed by meteorological data (amount of precipitation, air temperature, etc.). Materials of long-term observation over 11 districts of Astrakhan region and Astrakhan city were analyzed, including data on the spread of Ixodid ticks, population contact with them (according to the attendance of people to treatment-and-prophylactic organizations of the region). Statistical data processing was carried out using the method of straight-line alignment of dynamic series of morbidity indicators, calculation of the average annual rate of decrease/increase. Correlation analysis was used to assess the direction and strength of the relationship between the indicators, and quantitative dependence between epidemic process characteristics. Differences between the indicators were considered to be reliable if p < 0.05. Results. During the analyzed period 151 cases of CCHF and 3951 cases of ASF were identified. By 2016. CCHF was registered in all 11 districts of the region and the area of foci covered 44,000 km2 and 44,100 km2, respectively. There are no differences significantly affecting the epidemic process of CCHF and ASF, so preventive measures are mainly aimed at controlling the vectors of the pathogens of these infections. The comprehensive study of the territory of Astrakhan region carried out in 2000–2016 revealed expansion of CCHF and ASF areal of disease (by 11.8% and 23.4% respectively) and determined the territories with the highest risk of infection, which allowed to increase and redistribute the volumes of acaricide treatments of the territories with the highest infection risk and ensure the decrease of CCHF and ASF morbidity rates. Conclusion. As a result of the comprehensive study conducted in 2000–2016 in the territory of Astrakhan region, the expansion of CCHF and ASF areal of disease was revealed (by 11.8% and 23.4% respectively) and the areas of highest infection risk were identified, which allowed to increase and redistribute the volume of acaricide treatments of the areas of highest infection risk and ensure the reduction of CCHF and ASF morbidity.