Introduction <p>The true number of coronavirus disease-19 (COVID-19) cases may be highly underestimated because of reduced efforts to track cases through testing in the postpandemic era. Earlier estimates of this underreporting have varied across regions, and countries in Asia, Africa, the Middle East, and Latin America have been notably impacted. This study investigates the true burden of COVID-19 cases in 2023 and 2024 across Asia, Africa, the Middle East, and Latin America.</p> Methods <p>We conducted a retrospective analysis of national public health surveillance data from 2022 to 2024 on COVID-19 cases, hospitalizations, and deaths in Asia, Africa, the Middle East, and Latin America. Using a method developed by the US Centers for Disease Control and Prevention to estimate the burden of COVID-19 and influenza, we estimated the number of cases for 2023 and 2024 by calculating the ratio of cases to hospitalization and cases to deaths, using 2022 as the baseline. We compared the estimated and reported number of cases each year to assess the level of underreporting.</p> Results <p>The mean ratio of estimated cases to reported cases showed a high albeit variable level of underreporting in 2023 and 2024 across regions. In 2023, the levels of underreported cases were 1295%, 319%, 560%, and 3703% in Asia, the Middle East, Latin America, and Africa, respectively. The number of estimated underreported cases generally increased in 2024 to 2326%, 1415% and 16,664% in Asia, Latin America, and Africa, respectively, but in the Middle East decreased to 87% based on hospitalization data. The trend for death data was similar.</p> Conclusions <p>The results highlight the high level of underreporting of COVID-19 cases, which has increased over time in many regions. Therefore, the true global burden of COVID-19 could be substantially higher than indicated by publicly available data. Continued COVID-19 surveillance is crucial for stabilizing public health measures such as prevention and target vaccination programs.</p>