The lag between daily reported Covid-19 cases and deaths and its relationship to age


Background: The Coronavirus disease 2019 (Covid-19) has infected millions and killed tens of thousands of people. Public health measures put in place by governments are essential to the success of controlling this disease. However, governments may not feel as incentivized to implement these measures when deaths are not rising along with cases. However, it is known that a delay exists between the time of infection and the time of death. This study attempted to find how long that lag is and how the age of people infected may affect that lag.
Design and Methods: A descriptive and correlational study was carried out to investigate the length of the lag and the relationship between lag and age.

Results: The average lag between daily Covid-19 cases and deaths was 8.053 days with a standard deviation of 4.116 days for nineteen regions. After excluding data from three more regions due to unavailable age data, the regression yielded an equation of lag = 14.015 – 0.153 (% cases above 60) with a p-value of 0.066. Because the p-value of 0.066 is lower than the 0.10 significance level, there is evidence that a relationship exists between the lag and the age of cases.
Conclusions: The results show that regions must remain vigilant when Covid-19 cases rapidly increase without similar increases in deaths since there exists a significant lag between the two. Additionally, a younger demographic of cases may lead to an increased lag, further pushing regions into a false sense of security that should be avoided.


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