A cross-sectional study measuring contact patterns using diaries in an urban and a rural community in South Africa, 2018
Jackie Kleynhans, Stefano Tempia, Meredith McMorrow, Anne von Gottberg, Neil Martinson, Kathleen Kahn, Jocelyn Moyes, Thulisa Mkhencele, Limakatso Lebina, F. Xavier Gómez‐Olivé, Floidy Wafawanaka, Azwifarwi Mathunjwa, Cheryl Cohen, the PHIRST group, Amelia Buys, Angela Mathee, Brigitte Language, Lorens Maake, Florette K. Treurnicht, Katlego Mothlaoleng, Maimuna Carrim, Nicole Wolter, Orienka Hellferscee, Ryan G. Wagner, Stuart Piketh
Abstract
BACKGROUND: Describing contact patterns is crucial to understanding infectious disease transmission dynamics and guiding targeted transmission mitigation interventions. Data on contact patterns in Africa, especially South Africa, are limited. We measured and compared contact patterns in a rural and urban community, South Africa. We assessed participant and contact characteristics associated with differences in contact rates. METHODS: We conducted a cross-sectional study nested in a prospective household cohort study. We interviewed participants to collect information on persons in contact with for one day. We described self-reported contact rates as median number people contacted per day, assessed differences in contact rates based on participant characteristics using quantile regression, and used a Poisson model to assess differences in contact rates based on contact characteristics within age groups. We also calculated cumulative person hours in contact within age groups at different locations. RESULTS: We conducted 535 interviews (269 rural, 266 urban), with 17,252 contacts reported. The overall contact rate was 14 (interquartile range (IQR) 9-33) contacts per day. Those ≤18 years had higher contact rates at the rural site (coefficient 17, 95% confidence interval (95%CI) 10-23) compared to the urban site, for those aged 14-18 years (13, 95%CI 3-23) compared to < 7 years. No differences were observed for adults. There was a strong age-based mixing, with age groups interacting more with similar age groups, but also interaction of participants of all ages with adults. Children aged 14-18 years had the highest cumulative person hours in contact (116.3 rural and 76.4 urban). CONCLUSIONS: Age played an important role in the number and duration of contact events, with children at the rural site having almost double the contact rate compared to the urban site. These contact rates can be utilized in mathematical models to assess transmission dynamics of infectious diseases in similar communities.