If you don't disburse the vaccine and you don't track the impact of the disease on the population, the result is a perceived low mortality from the disease and/or misdiagnosis of the impact of the disease.
45th POTUS Trump faced a conundrum: On the one hand 45th POTUS Trump correctly took credit for producing the covid vaccine at "warp speed" to save lives, but on the other hand 45th POTUS Trump denied Am,erican deaths from covid and wouldn't put resources into tracking the extent of spread of the disease because the vaccine proved successful.
But there was a considerable time lapse before the vaccine was available and the spread of covid.
"How Trump's Denial and Misinformation led to the covid pandemic's dark winter," by Yesmeen, Abutableb, Ashley Parker, Josh Dawsey, and Philip Rucker, Dec. 19, 2020
https://www.congress.gov/118/meeting/house/115611/documents/HHRG-118-FD00-20230330-SD005.pdf
"Debunking the False Claim That COVID Death Counts Are Inflated," by Christie Aschwanden, Oct. 20, 2020 https://www.scientificamerican.com/article/debunking-the-false-claim-that-covid-death-counts-are-inflated1/
"In August, President Donald Trump retweeted a post claiming that only 6 percent of these reported deaths were actually from COVID-19." vs "94 percent of COVID-19 deaths reported by the Centers for Disease Control and Prevention “were the result of 2-3 additional serious illnesses and were of advanced age.”
"The Trump Administration and the COVID‐19 crisis: Exploring the warning‐response problems and missed opportunities of a public health emergency," by Charles F Parker and Eric K Stern
https://pmc.ncbi.nlm.nih.gov/articles/PMC9115435/