Finds the total number of infections for each iteration of an MCMC chain
get_total_number_infections(inf_chain, pad_chain = TRUE)a data table with `chain_no`, `samp_no`, and the total number of infections for each MCMC sample
if (FALSE) { # \dontrun{
inf_chain <- load_infection_chains(thin=10,burnin=5000,chain_subset=1:3)
n_infs <- get_total_number_infections(inf_chain$chain, pad_chain=FALSE)
} # }