Abstract:
BACKGROUND : In sub-Saharan Africa, acute respiratory infections (ARI), acute gastrointestinal infections (GI) and acute
febrile disease of unknown cause (AFDUC) have a large disease burden, especially among children, while respective
aetiologies often remain unresolved. The need for robust infectious disease surveillance to detect emerging
pathogens along with common human pathogens has been highlighted by the ongoing novel coronavirus disease
2019 (COVID-19) pandemic. The African Network for Improved Diagnostics, Epidemiology and Management of
Common Infectious Agents (ANDEMIA) is a sentinel surveillance study on the aetiology and clinical characteristics
of ARI, GI and AFDUC in sub-Saharan Africa.
METHODS : ANDEMIA includes 12 urban and rural health care facilities in four African countries (Côte d’Ivoire, Burkina
Faso, Democratic Republic of the Congo and Republic of South Africa). It was piloted in 2018 in Côte d’Ivoire and the
initial phase will run from 2019 to 2021. Case definitions for ARI, GI and AFDUC were established, as well as syndromespecific
sampling algorithms including the collection of blood, naso- and oropharyngeal swabs and stool. Samples are
tested using comprehensive diagnostic protocols, ranging from classic bacteriology and antimicrobial resistance
screening to multiplex real-time polymerase chain reaction (PCR) systems and High Throughput Sequencing. In March
2020, PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and analysis of full genomic
information was included in the study. Standardised questionnaires collect relevant clinical, demographic, socioeconomic
and behavioural data for epidemiologic analyses. Controls are enrolled over a 12-month period for a nested
case-control study. Data will be assessed descriptively and aetiologies will be evaluated using a latent class analysis
among cases. Among cases and controls, an integrated analytic approach using logistic regression and Bayesian
estimation will be employed to improve the assessment of aetiology and associated risk factors.
DISCUSSION : ANDEMIA aims to expand our understanding of ARI, GI and AFDUC aetiologies in sub-Saharan Africa using
a comprehensive laboratory diagnostics strategy. It will foster early detection of emerging threats and continued
monitoring of important common pathogens. The network collaboration will be strengthened and site diagnostic
capacities will be reinforced to improve quality management and patient care.
