Cost-effectiveness of public health strategies for COVID-19 epidemic control in South Africa: a microsimulation modelling study

Background: Health-care resource constraints in low-income and middle-income countries necessitate the identification of cost-effective public health interventions to address COVID-19. We aimed to develop a dynamic COVID-19 microsimulation model to assess clinical and economic outcomes and cost-effectiveness of epidemic control strategies in KwaZulu-Natal province, South Africa. Methods: We compared different combinations of five public health interventions: health-care testing alone, where diagnostic testing is done only for individuals presenting to health-care centres; contact tracing in households of cases; isolation centres, for cases not requiring hospital admission; mass symptom screening and molecular testing for symptomatic individuals by community health-care workers; and quarantine centres, for household contacts who test negative. We calibrated infection transmission rates to match effective reproduction number (Re) estimates reported in South Africa. We assessed two main epidemic scenarios for a period of 360 days, with an Re of 1·5 and 1·2. Strategies with incremental cost-effectiveness ratio (ICER) of less than US$3250 per year of life saved were considered cost-effective. We also did sensitivity analyses by varying key parameters (Re values, molecular testing sensitivity, and efficacies and costs of interventions) to determine the effect on clinical and cost projections. Findings: When Re was 1·5, health-care testing alone resulted in the highest number of COVID-19 deaths during the 360-day period. Compared with health-care testing alone, a combination of health-care testing, contact tracing, use of isolation centres, mass symptom screening, and use of quarantine centres reduced mortality by 94$340 per year of life saved). In settings where quarantine centres were not feasible, a combination of health-care testing, contact tracing, use of isolation centres, and mass symptom screening was cost-effective compared with health-care testing alone (ICER $590 per year of life saved). When Re was 1·2, health-care testing, contact tracing, use of isolation centres, and use of quarantine centres was the least costly strategy, and no other strategies were cost-effective. In sensitivity analyses, a combination of health-care testing, contact tracing, use of isolation centres, mass symptom screening, and use of quarantine centres was generally cost-effective, with the exception of scenarios in which Re was 2·6 and when efficacies of isolation centres and quarantine centres for transmission reduction were reduced. Interpretation: In South Africa, strategies involving household contact tracing, isolation, mass symptom screening, and quarantining household contacts who test negative would substantially reduce COVID-19 mortality and would be cost-effective. The optimal combination of interventions depends on epidemic growth characteristics and practical implementation considerations

Cost-effectiveness of public health strategies for COVID-19 epidemic control in South Africa

Background Healthcare resource constraints in low and middle-income countries necessitate selection of cost-effective public health interventions to address COVID-19. Methods We developed a dynamic COVID-19 microsimulation model to evaluate clinical and economic outcomes and cost-effectiveness of epidemic control strategies in KwaZulu-Natal, South Africa. Interventions assessed were Healthcare Testing (HT), where diagnostic testing is performed only for those presenting to healthcare centres; Contact Tracing (CT) in households of cases; Isolation Centres (IC), for cases not requiring hospitalisation; community health worker-led Mass Symptom Screening and diagnostic testing for symptomatic individuals (MS); and Quarantine Centres (QC), for contacts who test negative. Given uncertainties about epidemic dynamics in South Africa, we evaluated two main epidemic scenarios over 360 days, with effective reproduction numbers (R e ) of 1.5 and 1.2. We compared HT, HT+CT, HT+CT+IC, HT+CT+IC+MS, HT+CT+IC+QC, and HT+CT+IC+MS+QC, considering strategies with incremental cost-effectiveness ratio (ICER) <US$1,290/year-of-life saved (YLS) to be cost-effective. Findings With R e 1.5, HT resulted in the most COVID-19 deaths and lowest costs over 360 days. Compared with HT, HT+CT+IC+MS reduced mortality by 76$350/YLS). HT+CT+IC+MS+QC provided the greatest reduction in mortality, but increased costs by 95% compared with HT+CT+IC+MS and was not cost-effective (ICER $8,000/YLS). With R e 1.2, HT+CT+IC+MS was the least costly strategy, and HT+CT+IC+MS+QC was not cost-effective (ICER$294,320/YLS). Interpretation In South Africa, a strategy of household contact tracing, isolation, and mass symptom screening would substantially reduce COVID-19 mortality and be cost-effective. Adding quarantine centres for COVID-19 contacts is not cost-effective

Clinical Impact, Costs, and Cost-Effectiveness of Expanded SARS-CoV-2 Testing in Massachusetts

BACKGROUND: We projected the clinical and economic impact of alternative testing strategies on COVID-19 incidence and mortality in Massachusetts using a microsimulation model. METHODS: We compared four testing strategies: 1) Hospitalized: PCR testing only patients with severe/critical symptoms warranting hospitalization; 2) Symptomatic: PCR for any COVID-19-consistent symptoms, with self-isolation if positive; 3) Symptomatic+asymptomatic-once: Symptomatic and one-time PCR for the entire population; and, 4) Symptomatic+asymptomatic-monthly: Symptomatic with monthly re-testing for the entire population. We examined effective reproduction numbers (Re, 0.9-2.0) at which policy conclusions would change. We assumed homogeneous mixing among the Massachusetts population (excluding those residing in long-term care facilities). We used published data on disease progression and mortality, transmission, PCR sensitivity/specificity (70/100%) and costs. Model-projected outcomes included infections, deaths, tests performed, hospital-days, and costs over 180-days, as well as incremental cost-effectiveness ratios (ICER, $/quality-adjusted life-year [QALY]). RESULTS: At Re 0.9, Symptomatic+asymptomatic-monthly vs. Hospitalized resulted in a 64$100,000/QALY only when Re ≥1.6; when test cost was ≤$3, every 14-day testing was cost-effective at all Re examined. CONCLUSIONS: Testing people with any COVID-19-consistent symptoms would be cost-saving compared to testing only those whose symptoms warrant hospital care. Expanding PCR testing to asymptomatic people would decrease infections, deaths, and hospitalizations. Despite modest sensitivity, low-cost, repeat screening of the entire population could be cost-effective in all epidemic settings