Impact of COVID-19 on mortality in Peru using triangulation of multiple data sources

An analytic cross-sectional study was conducted to quantify the impact of COVID-19 on mortality in Peru. Total excess mortality due to natural and external causes was calculated. The direct and indirect impact of COVID19 was estimated at two points: when COVID-19 deaths were confirmed by a laboratory test and when they were confirmed by broader criteria (reclassified deaths). This comparison was made in general and by sex, age, and geographical location. The sensitivity of laboratory testing and of death certificates as criteria for confirmation of a COVID-19 death was calculated using reclassified deaths as the gold standard. From epidemiological week (EW) 10 of 2020 to EW 23 of 2021, 349 756 deaths occurred, for an excess of 183 237 deaths, mainly due to natural causes. A total of 100 955 deaths corresponded to deaths confirmed by laboratory tests; however, the reclassification criterion brought this figure to 188 708. Laboratory tests had 53.3% sensitivity; this was lower at the onset of the pandemic (10.6%) and during the first wave (37.8%). The sensitivity of death certificates was higher than laboratory tests (41.7% vs 23.9%) only during the months when little testing was available. These data showed that the impact of COVID-19 on mortality in Peru was mainly direct. Also, in periods with limited access to laboratory testing, death certificates were a useful source for determining deaths directly caused by COVID-19.