Dengue surfaced in febrile patients at every Ghanaian site, with facility rates varying sharply
Dengue was identified in a meaningful slice of febrile illness across three Ghanaian regions, and the signal was present at all six public facilities studied. Among 2,936 consenting patients aged 1 year and older, dengue NS1 and/or IgM positivity reached 6.95% overall, with 204 positive cases detected through ELISA-based testing. The distribution was not uniform: prevalence ranged from 3.88% at Kintampo to 12.32% at Atebubu, both in Bono East, a spread large enough to matter at the bedside and in local surveillance planning.
One finding stands out for clinicians who routinely triage undifferentiated fever in West Africa: dengue was not confined to a single pocket or season. It appeared across urban and rural service settings, including public facilities in Greater Accra, Bono East, and Upper West. In settings where malaria, typhoid, respiratory infections, and nonspecific viral syndromes often dominate the differential diagnosis, this level of dengue positivity means a portion of patients labeled as “febrile illness” are likely being managed without the correct virologic context.
Serology and antigen testing drew different slices of the epidemic picture
The laboratory pattern helps explain why dengue can remain hidden in routine care. Of the 204 positive patients, 31 were NS1-only, 161 were IgM-only, and 12 were dual-positive. NS1 antigen generally reflects more acute infection, while IgM indicates recent immune response and may linger beyond the narrow window when RNA is easiest to detect. In practical terms, the serologic profile suggests a mix of current and recently resolved infections circulating through the outpatient stream rather than a single synchronized outbreak.
Among the 43 NS1-positive samples, RT-PCR detected dengue RNA in eight. Five of those were DENV-1 from Bono East and three were DENV-3 from Upper West. The RNA yield was modest, but the confirmation is clinically important because it anchors the serology in active viral circulation and documents which serotypes were present in the sampled regions. Serotype detection also matters for future risk assessment, since sequential infections with different dengue serotypes can influence disease severity through immune-mediated mechanisms.
Older age tracked with higher odds of positivity, while season offered no clean divide
Adjusted analyses showed a stepwise age association: the odds of dengue positivity increased with age, with an adjusted odds ratio of 1.09 per five years. In a febrile population, that pattern suggests cumulative exposure may be building over time, although the study design does not allow direct attribution of prior infections, mobility patterns, or household-level risk. Even so, the age gradient is a useful reminder that dengue is not only a pediatric concern and should remain on the radar in adults presenting with fever, headache, myalgia, or constitutional symptoms that can overlap with malaria or influenza-like syndromes.
There was no clear rainy-dry season difference. For clinicians and public health teams, that absence of a strong seasonal split narrows the usefulness of calendar-based assumptions. Mosquito-borne transmission often rises with rainfall and vector breeding opportunities, but the data here do not support relying on season alone to decide when dengue belongs in the workup. Fever surveillance that is blind to dengue outside peak rainy periods will miss cases.
Facility-level differences point to local transmission pressure and diagnostic blind spots
The variation between Kintampo and Atebubu is more than a statistical curiosity. It likely reflects a blend of local vector ecology, population movement, healthcare-seeking behavior, and the intensity of transmission around each catchment area. A facility seeing roughly triple the prevalence of another is not just measuring disease; it is measuring how unevenly risk is distributed across a health system that may otherwise treat febrile illness as a single category.
This has immediate implications for clinical practice in Ghana. When dengue is not routinely considered, patients may receive treatment aimed at malaria or bacterial illness while the actual cause goes unrecognized. NS1 and IgM testing, paired with RT-PCR where available, can sharpen diagnosis and reduce blind empiricism. The study does not provide outcome data on misdiagnosis or treatment delays, but the diagnostic gap is obvious from the prevalence itself: a nontrivial proportion of febrile patients carried evidence of dengue infection.
Laboratory-supported surveillance is the hinge between case finding and control
The study design strengthens the public health signal. Investigators used cross-sectional surveillance among consenting febrile patients at six public facilities, approached consecutive eligible patients, and applied ELISA testing for NS1 antigen and IgM antibody, followed by RT-PCR and serotyping in NS1-positive samples. That combination allowed a layered view of dengue circulation rather than a single yes-or-no estimate. It also provides a template for surveillance in settings where laboratory capacity is limited but febrile patient volume is high enough to reveal circulation patterns.
The consequences extend beyond individual diagnosis. Where dengue circulates alongside other febrile infections, routine surveillance can help clarify whether rising fever presentations reflect seasonal malaria shifts, arboviral expansion, or both. The presence of DENV-1 and DENV-3 in separate regions also argues against treating dengue as a uniform, isolated event. Viral movement is already established, and the study captures it in a way that should inform future diagnostics, clinician education, and vector-control planning.
Ghana’s febrile illness algorithms may need a broader arboviral lens
This preprint does not claim to define the national burden of dengue, and it should not be stretched that far. Sampling came from selected public facilities in three ecological strata, not a population-wide household survey. The study also did not report a clear rainy-dry season effect, which limits simple seasonal forecasting. Still, the central message is hard to miss: dengue is present in febrile patients across multiple Ghanaian sites, and active viral circulation has been confirmed by RT-PCR.
In a health system where fever is still too often collapsed into malaria first, dengue needs a place in the diagnostic hierarchy. The data support broader laboratory-backed surveillance and a lower threshold for considering dengue in patients with unexplained fever, especially in regions where facility-level prevalence was highest and where serotype-confirmed transmission has already been documented.