Currently, airborne transmission is seen as the most important transmission path for SARS-CoV-2. In this investigation, models of other researchers with the aim to predict an infection risk for exposed persons in a room through aerosols emitted by an infectious case-patient were extended. As a novelty parameters or boundary conditions, namely the non-stationarity of aerosol and the half life of aerosolized virus, were included and a new method for determining the quanta emission rate based on measurements of the particle emission rate and respiratory rate at different types of activities was implemented. As a second step, the model was applied to twelve outbreaks to compare the predicted infection risk with the observed attack rate. To estimate a 'credible interval' of the predicted infection risk the quanta emission rate, the respiratory rate as well as the air volume flow were varied. In nine out of twelve outbreaks, the calculated predicted infection risk via aerosols was found to be in the range the attack rate (with the variation of the boundary conditions) and reasons for the observed larger divergence were discussed. The validation was considered successful and therefore, the use of the model could be recommended to predict the risk of an infection via aerosols in given situations. Furthermore, appropriate preventive measures can be designed.

Infection with the hepatitis C virus (HCV) is a global health concern, with an estimated 71 million people infected in 2015 and 400 000 deaths each year. [1][2][3][4][5][6][7][8][9][10] HCV is the leading cause of liver disease, and there is currently no vaccination available to protect against it. Drugs known as direct-acting antivirals (DAAs) have now been approved for children as young as 3 years old. HCV elimination techniques for children, on the other hand, have yet to be developed. [10][11][12][13][14][15][16][17][18][19][20][21] Estimates of paediatric prevalence are needed to aid in the scaling up of therapy and screening and testing approaches for this population. The prevalence of HCV in this unique community has not been adequately investigated. [2][3][4][5][6][7][8][9] In Western Europe, the prevalence is expected to be 1.5% to 3.5%, but barely 0.5% in the United Kingdom, with little information on the prevalence in low-income countries. [2][3][4][5][6][7][8][9][10] HCV infection raises the risk of morbidity and mortality, and it is the major cause of end-stage liver disease, cirrhosis and liver cancer in people all over the world. [18][19][20][21][22][23] Despite the fact that HCV infection seldom causes morbidity in children, the majority of HCV-infected children develop chronic HCV, putting them at risk for life-threatening liver disease. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] Furthermore, some research suggests that HCV has an impact on children's quality of life and behaviour, as cognitive function has been proven to be impaired, and families have reported greater levels of stress, both of which have a negative impact on family connections and well-being. [21][22][23][24][25][26][27] There are few statistics on the prevalence of HCV in children at the moment. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] The purpose of this study was to look at