RESUMO
Background: Arboviruses are endemic in Uganda; however, little is known about their epidemiology, seasonality and spatiotemporal distribution. Our study sought to provide information on arbovirus outbreaks from acute clinical presentations. Methods: Immunoglobulin M (IgM) and confirmatory Plaque Reduction Neutralisation Test (PRNT) results for arbovirus diagnosis of samples collected from patients attending sentinel sites from 2016-19 were analysed retrospectively. Demographic data were analysed with SaTScan and SPSS software to determine the epidemiology and spatiotemporal distribution of arboviruses. Results: Arbovirus activity peaked consistently during March-May rainy seasons. Overall, arbovirus seroprevalence was 9.5%. Of 137 IgM positives, 52.6% were confirmed by PRNT, of which 73.6% cases were observed in central Uganda with Yellow Fever Virus had the highest prevalence (27.8%). The 5-14 age group were four times more likely to be infected with an arbovirus p=0.003, 4.1 (95% CI 1.3-12.3). Significant arboviral activity was observed among outdoor workers(p=0.05) . Spatiotemporal analysis indicated arboviral activity in 23 of the 85 districts analysed.. Interpretation: Our study shows that arbovirus activity peaks during the March-May rainy season and highlights the need for YFV mass vaccination to reduce the clinical burden of arboviruses transmitted within the region.
RESUMO
Arboviruses are (re-) emerging viruses that cause significant morbidity globally. Clinical manifestations usually consist of a non-specific febrile illness that may be accompanied by rash, arthralgia and arthritis and/or with neurological or hemorrhagic syndromes. The broad range of differential diagnoses of other infectious and non-infectious etiologies presents a challenge for clinicians. While knowledge of the geographic distribution of pathogens and the current epidemiological situation, incubation periods, exposure risk factors and vaccination history can help guide the diagnostic approach, the non-specific and variable clinical presentation can delay final diagnosis. This case report summarizes the laboratory-based findings of three travel-related cases of arbovirus infections in Uganda. These include a patient from Bangladesh with chikungunya virus infection and two cases of dengue fever from Ethiopia. Early detection of travel-imported cases by public health laboratories is important to reduce the risk of localized outbreaks of arboviruses such as dengue virus and chikungunya virus. Because of the global public health importance and the continued risk of (re-) emerging arbovirus infections, specific recommendations following diagnosis by clinicians should include obtaining travel histories from persons with arbovirus-compatible illness and include differential diagnoses when appropriate.