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. 2023 Nov;17(11):e13200.
doi: 10.1111/irv.13200.

Transmissibility and severity of COVID-19 in a humanitarian setting: First few X investigation of cases and contacts in Juba, South Sudan, 2020

Richard Lino Loro Lako  1 , Niamh Meagher  2 , Joseph Francis Wamala  3 , John Ndyahikayo  3 , Ayesheshem Ademe Tegegne  3 , Olushayo Oluseun Olu  3 , David J Price  2   4 , Soatiana Rajatonirina  5 , Elise Farley  5 , Joseph Chukwudi Okeibunor  5 , Valerie Ann Mize  3
Affiliations

Transmissibility and severity of COVID-19 in a humanitarian setting: First few X investigation of cases and contacts in Juba, South Sudan, 2020

Richard Lino Loro Lako et al. Influenza Other Respir Viruses. 2023 Nov.

Abstract

Background: The first few 'X' (FFX) studies provide evidence to guide public health decision-making and resource allocation. The adapted WHO Unity FFX protocol for COVID-19 was implemented to gain an understanding of the clinical, epidemiological, virological and household transmission dynamics of the first cases of COVID-19 infection detected in Juba, South Sudan.

Methods: Laboratory-confirmed COVID-19 cases were identified through the national surveillance system, and an initial visit was conducted with eligible cases to identify all close contacts. Consenting cases and close contacts were enrolled between June 2020 and December 2020. Demographic, clinical information and biological samples were taken at enrollment and 14-21 days post-enrollment for all participants.

Results: Twenty-nine primary cases and 82 contacts were included in the analyses. Most primary cases (n = 23/29, 79.3%) and contacts (n = 61/82, 74.4%) were male. Many primary cases (n = 18/29, 62.1%) and contacts (n = 51/82, 62.2%) were seropositive for SARS-CoV-2 at baseline. The secondary attack rate among susceptible contacts was 12.9% (4/31; 95% CI: 4.9%-29.7%). All secondary cases and most (72%) primary cases were asymptomatic. Reported symptoms included coughing (n = 6/29, 20.7%), fever or history of fever (n = 4/29, 13.8%), headache (n = 3/29, 10.3%) and shortness of breath (n = 3/29, 10.3%). Of 38 cases, two were hospitalised (5.3%) and one died (2.6%).

Conclusions: These findings were used to develop the South Sudanese Ministry of Health surveillance and contract tracing protocols, informing local COVID-19 case definitions, follow-up protocols and data management systems. This investigation demonstrates that rapid FFX implementation is critical in understanding the emerging disease and informing response priorities.

Keywords: COVID-19; South Sudan; first few X; transmission investigation.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

FIGURE 1
FIGURE 1
Diagram of participant flow through the investigation.
FIGURE 2
FIGURE 2
Age distribution of primary cases and contacts by baseline SARS‐CoV‐2 serostatus.
FIGURE 3
FIGURE 3
Exposures reported by the 29 primary cases in the 14 days prior to baseline assessment.
FIGURE 4
FIGURE 4
Symptoms recorded among primary cases at baseline.
See this image and copyright information in PMC

References

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