Modeling geographic vaccination strategies for COVID-19 in Norway

• Published in: PLoS computational biology 2024-01, Vol.20 (1), p.e1011426
• Main Authors: Chan, Louis Yat Hin, Rø, Gunnar, Midtbø, Jørgen Eriksson, Di Ruscio, Francesco, Watle, Sara Sofie Viksmoen, Juvet, Lene Kristine, Littmann, Jasper, Aavitsland, Preben, Nygård, Karin Maria, Berg, Are Stuwitz, Bukholm, Geir, Kristoffersen, Anja Bråthen, Engø-Monsen, Kenth, Engebretsen, Solveig, Swanson, David, Palomares, Alfonso Diz-Lois, Lindstrøm, Jonas Christoffer, Frigessi, Arnoldo, de Blasio, Birgitte Freiesleben
• Format: Article
• Language: English
• Subjects: Age; Aged; Biology and Life Sciences; Computer industry; COVID-19; COVID-19 vaccines; Disease transmission; Earth Sciences; Emergency preparedness; Epidemiology; Ethics; Fatalities; Health aspects; Immunization; Infection; Infections; International economic relations; Mathematical models; Medical personnel; Medical research; Medicine and Health Sciences; Medicine, Experimental; Metapopulations; Methods; Older people; Pandemics; Patient admissions; People and Places; Personal information; Population; Population density; Public health; Risk; Severe acute respiratory syndrome coronavirus 2; Strategy; Vaccination; Vaccines
• ISSN: 1553-7358; 1553-734X; 1553-7358
• DOI: 10.1371/journal.pcbi.1011426

Vaccination was a key intervention in controlling the COVID-19 pandemic globally. In early 2021, Norway faced significant regional variations in COVID-19 incidence and prevalence, with large differences in population density, necessitating efficient vaccine allocation to reduce infections and severe outcomes. This study explored alternative vaccination strategies to minimize health outcomes (infections, hospitalizations, ICU admissions, deaths) by varying regions prioritized, extra doses prioritized, and implementation start time. Using two models (individual-based and meta-population), we simulated COVID-19 transmission during the primary vaccination period in Norway, covering the first 7 months of 2021. We investigated alternative strategies to allocate more vaccine doses to regions with a higher force of infection. We also examined the robustness of our results and highlighted potential structural differences between the two models. Our findings suggest that early vaccine prioritization could reduce COVID-19 related health outcomes by 8% to 20% compared to a baseline strategy without geographic prioritization. For minimizing infections, hospitalizations, or ICU admissions, the best strategy was to initially allocate all available vaccine doses to fewer high-risk municipalities, comprising approximately one-fourth of the population. For minimizing deaths, a moderate level of geographic prioritization, with approximately one-third of the population receiving doubled doses, gave the best outcomes by balancing the trade-off between vaccinating younger people in high-risk areas and older people in low-risk areas. The actual strategy implemented in Norway was a two-step moderate level aimed at maintaining the balance and ensuring ethical considerations and public trust. However, it did not offer significant advantages over the baseline strategy without geographic prioritization. Earlier implementation of geographic prioritization could have more effectively addressed the main wave of infections, substantially reducing the national burden of the pandemic.