The emergence and fast global spread of COVID-19 has presented one of the greatest public health challenges in modern times with no proven cure or vaccine. Africa is still early in this epidemic, therefore the extent of disease severity is not yet clear. We used a mathematical model to fit to the observed cases of COVID-19 in South Africa to estimate the basic reproductive number and critical vaccination coverage to control the disease for different hypothetical vaccine efficacy scenarios. We also estimated the percentage reduction in effective contacts due to the social distancing measures implemented. Early model estimates show that COVID-19 outbreak in South Africa had a basic reproductive number of 2.95 (95% credible interval [CrI] 2.83-3.33). A vaccine with 70% efficacy had the capacity to contain COVID-19 outbreak but at very higher vaccination coverage 94.44% (95% Crl 92.44-99.92%) with a vaccine of 100% efficacy requiring 66.10% (95% Crl 64.72-69.95%) coverage. Social distancing measures put in place have so far reduced the number of social contacts by 80.31% (95% Crl 79.76-80.85%). These findings suggest that a highly efficacious vaccine would have been required to contain COVID-19 in South Africa. Therefore, the current social distancing measures to reduce contacts will remain key in controlling the infection in the absence of vaccines and other therapeutics.

/pdf/quantifying-early-covid-19-outbreak-transmission-in-south-3cwdartwot.pdf

Quantifying early COVID-19 outbreak transmission in South Africa and exploring vaccine efficacy scenarios.

Vaccinations are an important and effective cornerstone of preventive medical care. Growing technologic capabilities and use by both patients and providers present critical opportunities to leverage these tools to improve vaccination rates and public health. We propose the Social Ecological Model as a useful theoretical framework to identify areas in which technology has been or may be leveraged to target undervaccination across the individual, interpersonal, organizational, community, and society levels and the ways in which these levels interact.

https://www.tandfonline.com/doi/pdf/10.1080/21645515.2018.1477458

The use of technology to promote vaccination: A social ecological model based framework.

Background: COVID-19 has emerged and spread at great speed globally and has presented one of the greatest public health challenges in modern times with no proven cure or vaccine. Africa is still early in this epidemic, therefore the spectrum of disease severity is not yet clear.

Methods: We used a mathematical model to fit to the observed cases of COVID-19 in South Africa to estimate the basic reproductive number and critical vaccination coverages to control the disease for different hypothetical vaccine efficacy scenarios. We also estimated the percentage reduction in effective contacts due to the social distancing measures implemented.

Results: Early model estimates show that COVID-19 outbreak in South Africa had a basic reproductive number of 2.95(95% credible interval [CrI] 2.83-3.33). A vaccine with 70% efficacy had the capacity to contain COVID-19 outbreak but at very higher vaccination coverage 94.44% (95% Crl 92.44-99.92%) with a vaccine of 100% efficacy requiring 66.10% (95% Crl 64.72-69.95%) coverage. Social distancing measures put in place have so far reduced the number of social contacts by 80.31% (95% Crl 79.76-80.85%).

Conclusions: Findings suggest a highly efficacious vaccine would have been required to contain COVID-19 in South Africa. Therefore, the current social distancing measures to reduce contacts will remain key in controlling the infection in the absence of vaccines and other therapeutics.

Funding Statement: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Declaration of Interests: The authors declare that they have no conflict of interest.

Ethics Approval Statement: The authors stated that ethics approval was not required for this study.

/pdf/quantifying-early-covid-19-outbreak-transmission-in-south-3v20bqvand.pdf

Quantifying Early COVID-19 Outbreak Transmission in South Africa and Exploring Vaccine Efficacy Scenarios

https://doi.org/10.1016/j.vaccine.2022.05.073

Comparative effectiveness of mandates and financial policies targeting COVID-19 vaccine hesitancy: A randomized, controlled survey experiment

Background COVID-19 has emerged and spread at great speed globally and has presented one of the greatest public health challenges in modern times with no proven cure or vaccine. Africa is still early in this epidemic, therefore the spectrum of disease severity is not yet clear. Methods We used a mathematical model to fit to the observed cases of COVID-19 in South Africa to estimate the basic reproductive number and critical vaccination coverages to control the disease for different hypothetical vaccine efficacy scenarios. We also estimated the percentage reduction in effective contacts due to the social distancing measures implemented. Results Early model estimates show that COVID-19 outbreak in South Africa had a basic re-productive number of 2.95 (95% credible interval [CrI] 2.83-3.33). A vaccine with 70% efficacy had the capacity to contain COVID-19 outbreak but at very higher vaccination coverage 94.44% (95% Crl 92.44-99.92%) with a vaccine of 100% efficacy requiring 66.10% (95% Crl 64.72-69.95%) coverage. Social distancing measures put in place have so far reduced the number of social contacts by 80.31% (95% Crl 79.76-80.85%). Conclusions Findings suggest a highly efficacious vaccine would have been required to contain COVID-19 in South Africa. Therefore, the current social distancing measures to reduce contacts will remain key in controlling the infection in the absence of vaccines and other therapeutics.

/pdf/quantifying-early-covid-19-outbreak-transmission-in-south-4t6g1zl4xq.pdf

Quantifying early COVID-19 outbreak transmission in South Africa and exploring vaccine efficacy scenarios

Purpose: This study was conducted to characterize the vaccination practices and challenges of family medicine physicians in Los Angeles County, California.Methods: The Los Angeles Academy of Family...

https://www.tandfonline.com/doi/pdf/10.1080/21645515.2018.1543524

Lucy Baden

Papers

Logistical and structural challenges are the major obstacles for family medicine physicians' ability to administer adult vaccines.