COVID-19 in Pakistan: A national analysis of five pandemic waves

ABSTRACT Objectives The COVID-19 pandemic showed distinct waves where cases ebbed and flowed. While each country had slight, nuanced differences, lessons from each wave with country-specific details provides important lessons for prevention, understanding medical outcomes and the role of vaccines. This paper compares key characteristics from the five different COVID-19 waves in Pakistan. Methods We used specific criteria to define COVID-19 waves, and key variables such as COVID-19 tests, cases, and deaths with their rates of change to the peak and then to the trough were used to draw descriptive comparisons. Additionally, a linear regression model estimated daily new COVID-19 deaths in Pakistan. Results Pakistan saw five distinct waves, each of which displayed the typical topology of a complete infectious disease epidemic. The time from wave-start to peak became progressively shorter, and from wave-peak to trough, progressively longer. Each wave appears to also be getting shorter, except for wave 4, which lasted longer than wave 3. A one percent increase in vaccinations increased daily new COVID-19 deaths by 0.10% (95% CI: 0.01, 0.20) in wave 4 and decreased deaths by 0.38% (95% CI: -0.67, -0.08) in wave 5. Conclusion Each wave displayed distinct characteristics that must be interpreted in the context of the level of response and the variant driving the epidemic. Key indicators suggest that COVID-19 preventive measures kept pace with the disease. Waves 1 and 2 were mainly about prevention and learning how to clinically manage patients. Vaccination started late during Wave 3 and its impact became apparent on hospitalizations and deaths in Wave 5. The impact of highly virulent strains Alpha/B1.1.7 and Delta/B.1.617.2 variants during Wave 3 and milder but more infectious Omicron/BA.5.2.1.7 are apparent.