Household transmission of SARS-CoV-2 in a rural area in South Africa

BACKGROUND

Patterns of SARS-CoV-2 spread have varied by geolocation, with differences in seroprevalence between urban and rural areas, and between waves. Household spread of SARS-CoV-2 is a known source of new COVID-19 infections, with rural areas in sub-Saharan Africa being more prone than urban areas to COVID-19 transmission because of limited access to water in some areas, delayed health- seeking behaviour and poor access to care.

OBJECTIVES

To explore SARS-CoV-2 infection incidence and transmission in rural households in South Africa (SA).

METHODS

We conducted a prospective household cluster investigation between 13 April and 21 July 2021 in the Matjhabeng subdistrict, a rural area in Free State Province, SA. Adults with SARS-CoV-2 confirmed by polymerase chain reaction (PCR) tests (index cases, ICs) and their household contacts (HCs) were enrolled. Household visits conducted at enrolment and on days 7, 14 and 28 included interviewer- administered questionnaires and respiratory and blood sample collection for SARS-CoV-2 PCR and SARS-CoV-2 immunoglobulin G serological testing, respectively. Co-primary cases were HCs with a positive SARS-CoV-2 PCR test at enrolment. The incidence rate (IR), using the Poisson distribution, was HCs with a new positive PCR and/or serological test per 1 000 person-days. Associations between outcomes and HC characteristics were adjusted for intra-cluster correlation using robust standard errors. The secondary infection rate (SIR) was the proportion of new COVID-19 infections among susceptible HCs.

RESULTS

Among 23 ICs and 83 HCs enrolled, 10 SARS-CoV-2 incident cases were identified, giving an IR of 5.8 per 1 000 person-days (95% confidence interval (CI) 3.14 - 11.95). Households with a co-primary case had higher IRs than households without a co-primary case (crude IR 14.16 v. 1.75, respectively; p=0.054). HIV infection, obesity and the presence of chronic conditions did not materially alter the crude IR. The SIR was 15.9% (95% CI 7.90 - 29.32). Households with a lower household density (fewer household members per bedroom) had a higher IR (IR 9.58; 95% CI 4.67 - 21.71) than households with a higher density (IR 3.06; 95% CI 1.00 - 12.35).

CONCLUSION

We found a high SARS-CoV-2 infection rate among HCs in a rural setting, with 48% of households having a co-primary case at the time of enrolment. Households with co-primary cases were associated with a higher seroprevalence and incidence of SARS-CoV-2. Sociodemographic and health characteristics were not associated with SARS-CoV-2 transmission in this study, and we did not identify any transmission risks inherent to a rural setting.

Practice Facilitation to Support Family Physicians in Encouraging COVID-19 Vaccine Uptake: A Multimethod Process Evaluation

PURPOSE

We offered a practice facilitation intervention to family physicians in Ontario, Canada, known to have large numbers of patients not yet vaccinated against coronavirus disease 2019 (COVID-19).

METHODS

We conducted a multimethod process evaluation embedded within a randomized controlled trial (clinical trial #NCT05099497). We collected descriptive statistics regarding engagement and qualitative interview data from family physicians and practice facilitators, as well as data from facilitator field notes. We analyzed and triangulated the data using thematic analysis and mapped barriers to and enablers for implementation to structural, organizational, physician, and patient factors.

RESULTS

Of the 300 approached, 90 family physicians (30%) accepted facilitation. Of these, 57% received technical support to identify unvaccinated patients, 29% used trained medical student volunteers to contact patients on their behalf, and 30% used automated calling to reach patients. Key factors affecting engagement with the intervention were staff shortages owing to COVID-19 (structural), clinic characteristics such as technical issues and gatekeeping by staff, which prevented facilitators from talking with physicians (organizational), burnout (physician), and specialized populations that required targeted resources (patient). The facilitator's ability to address technical issues and connect family physicians with medical students helped with engagement.

CONCLUSIONS

Strategies to help underresourced family physicians serving high-needs populations for issues of public health importance, such as vaccine promotion, must acknowledge the scarcity of physicians' time and provide new resources. To successfully engage family physicians, practice facilitators should seek to build trust and relationships over time, including with front-office staff.