The proportion of patients requiring intensive care significantly reduced from 6.7% ( We observed a reduction over time of the proportion of patients with Covid-19 requiring intensive 46 care, along with decreasing median values of viral load. As the epidemiological context changes 47 from high to low transmission setting, people are presumably exposed to a lower viral load, which 48 has been previously associated to less severe clinical manifestations. 
Of course, other factors might have had an influence on the decrease of severe cases, such as stricter 119 adherence to quarantine of the most fragile groups of people (i.e. those with chronic conditions, the 120 elderly). In our cohort, median age increased from March to April, but older age has been 121 associated to a worse outcome [10], so we suppose that this factor might not have a major role in 122 our findings. Conversely, the relevance of the transmission setting seems plausible, and efforts 