The reproduction number 𝑅 is a key indicator used to monitor the dynamics of Covid-19 and to assess the effects of infection control strategies that frequently have high social and economic costs.

The coronavirus disease 2019 (COVID-19) pandemic started with an outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, Hubei province, China, in December 2019. Since ...

We published an article earlier this month that contained incorrect estimates for the basic reproduction number (R0) for COVID subvariants BA.4/BA.5 and BA.2. We have now corrected the error, but I ...

Scientists say there is no evidence that the BA.5 version of the Omicron coronavirus variant is more transmissible than measles, or that it has a basic reproduction number, or "R-naught" (R0), of 18.6 ...

Empirical and statistical evidence suggests that the number of trips taken per year varies significantly among people by age, gender, income, occupation, ethnicity, region, and so on. Only a small ...

Among the well-known diseases, measles and chickenpox are two of the most infectious. But how does their contagiousness compare to the Delta variant of SARS-CoV-2 that is now causing the majority of ...