Title : Missed opportunities in mpox surveillance in Lukulu district, Zambia (February 2025): Implications for outbreak response
Abstract:
Introduction:
Mpox, a zoonotic disease caused by the monkeypox virus, has historically been confined to Central and West Africa. However, the emergence of cases in Zambia highlights critical weaknesses in the country’s disease surveillance system. A recent outbreak in Lukulu District, Western Zambia, exposed significant deficiencies in case detection, contact tracing, and community engagement. This study investigates missed opportunities in outbreak response and their implications for public health preparedness in rural settings.
Methods:
We conducted a case study of the index Mpox case, analyzing epidemiological data and contact tracing. Five initial contacts were identified during tracing; but critical, a bed-sharing contact was missed. Active case finding identified 18 contacts linked to the missed individual. Skin lesion swabs and blood samples were collected for real-time Polymerase Chain Reaction and genomic sequencing. Data from contacts were analyzed using R software, and included demographics, type of contact and level of risk exposure.
Results:
Detection and notification timeliness were 5 days and 1 day, respectively. However, key gaps in the surveillance system were evident. A critical contact, a bed-sharer of the index case, missed during the initial investigation, developed Mpox symptoms 15 days post-exposure, going undetected. Among the 18 contacts identified and linked to the missed individual, 10 (56%) were females, 7 (70%) of whom were ages 15 years and above. Nine (50%) of the contacts were household-members. Prolonged face-to-face contact was the most reported exposure type, with 10 (56%) contacts, followed by both direct physical and contact with contaminated material at 4 (22.2%) contacts each. Risk exposure level was categorized as medium in 50% (9/18) of contacts and high in 22% (4/18).
Discussion:
Despite testing negative for Mpox (on PCR), the missed contact’s clinical presentation, exposure history and movement patterns underscore the risks posed by gaps in surveillance and RCCE. Strengthening healthcare worker knowledge of Mpox, contact tracing protocols, diagnostic.
