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Is Ghana Prepared for Another Arboviral Outbreak? Evaluating the 2024 Dengue Fever Outbreak in the Context of Past Yellow Fever, Influenza, and COVID-19 Outbreaks.

Arboviruses are a growing concern in many nations. Several reports of arboviral outbreaks have been recorded globally in the past decade alone. Repeated arboviral outbreaks in developing countries have consistently highlighted vulnerabilities in disease surveillance and response systems, exposing critical gaps in early detection, contact tracing, and resource allocation. The 2024 Dengue fever outbreak in Ghana, which recorded 205 confirmed cases out of 1410 suspected cases, underscored the urgent need to evaluate the country's preparedness for arboviral outbreaks, given the detection of compet

Early photoperiodic cues modulate capacity for adult cold tolerance in the yellow fever mosquito Aedes aegypti.

Climate change is driving the rapid range expansion of Aedes aegypti into temperate regions, presenting novel seasonal cues that can affect seasonal plasticity. Seasonal plasticity in Ae. aegypti is well studied in eggs but remains understudied in adults. Here, we investigated the effects of photoperiod and temperature on thermal plasticity, measured by the ability to cold acclimate, and other dormancy-related traits in female Ae. aegypti adults. Cold acclimation was done under a short-day (SD) and long-day (LD) photoperiod. LD photoperiod was introduced at three life stages: parental generati

Decoding yellow fever virus immunogenicity: Targeting highly effective epitopes of YFV for next-generation vaccine design.

Yellow fever (YF) remains a significant public health concern despite the success of the live-attenuated YF-17D vaccine. While YF-17D serves as a benchmark for durable protection, its inherent drawbacks, including cold-chain dependence, contraindications for vulnerable populations, and rare severe adverse events, necessitate the development of safer, more deployable alternatives. The core of next-generation vaccine design lies in the systematic identification and functional validation of highly effective YFV epitopes. The robust immunogenicity of YF-17D is characterized by a polyfunctional, mu…

Yellow fever virus outbreak caused declines in survival and modified dispersal of wild golden lion tamarins.

Research Highlight: Ponchon, A., Choquet, R., Martins, A., Ruiz-Miranda, C., Albert, C., & Romano, V. (2026). Yellow fever outbreak temporarily changes dispersal patterns in an endangered primate. Journal of Animal Ecology. https://doi.org/10.1111/1365-2656.70250. Infectious diseases can be drivers of wildlife population dynamics, but how they reshape host movement and social organization remains poorly understood. Ponchon et al. (2026) present one of the rare examples where the impact of a disease outbreak on survival can be measured across a population of wild mammals and subsequently linked…

Revealing viral hepatitis epidemiology in the Democratic Republic of Congo: insights from yellow fever surveillance reanalysis.

BACKGROUND: Yellow fever surveillance systems are designed to identify cases of acute febrile jaundice, a clinical syndrome used to monitor the emergence of yellow fever outbreaks. However, this syndrome has diverse etiologies, particularly viral hepatitis. This study investigates the seroepidemiology of viral hepatitis A (HAV), B (HBV), C (HCV), and E (HEV) among cases initially suspected to be yellow fever, aiming to elucidate the epidemiology of viral hepatitis in the Democratic Republic of Congo (DRC) and provide insights for improving public health interventions. METHODS: A retrospective…

Identification of potential inhibitors targeting yellow fever virus helicase through ligand and structure-based computational studies.

Yellow fever is a flavivirus having plus-sensed RNA which encodes a single polyprotein. Host proteases cut this polyprotein into seven nonstructural proteins including a vital NS3 protein. The present study aims to identify the most effective inhibitor against the helicase (NS3) using different advanced ligand and structure-based computational studies. A set of 300 ligands was selected against helicase by chemical structural similarity model, which are similar to S-adenosyl-l-cysteine using infiniSee. This tool screens billions of compounds through a similarity search from in-built chemical sp…

Specialized cis-Acting RNA Elements Balance Genome Cyclization to Ensure Efficient Replication of Yellow Fever Virus.

Genome cyclization is essential for viral RNA (vRNA) replication of the vertebrate-infecting flaviviruses, and yet its regulatory mechanisms are not fully understood. Yellow fever virus (YFV) is a notorious pathogenic flavivirus. Here, we demonstrated that a group of cis-acting RNA elements in YFV balance genome cyclization to govern efficient vRNA replication. It was shown that the downstream of the 5'-cyclization sequence hairpin (DCS-HP) is conserved in the YFV clade and is important for efficient YFV propagation. By using two different replicon systems, we found that the function of the DC…

Количественное обнаружение вируса Сабойи в режиме реального времени: Флавирусный член генетики желтой лихорадки.

В роде Флавивирус во Флавириде есть родившиеся артропод вирусы, связанные с большим бременем для здоровья населения, такими как Зика, Денге или Желтая лихорадка. Вирус Сабойи (SABV) — неизученный флавивирус в той же генетической подгруппе, что и вирус Желтой лихорадки (YFV) вместе с вирусом Сепика (SEPV) и вирусом Вессельброна (WSLV). Инфекции флавивируса характеризуются неспециальными клиническими представлениями, что ведет к высокому риску неправильной диагностики. Было продемонстрировано, что вирус SABV циркулирует в Сахелианской зоне и в Центральной Африке. Для изучения этого вируса была р

Совпадение в аннотации оригинала
The genus Flavivirus in the Flaviridae contains arthropod born viruses associated with high public health burdens like Zika, Dengue or Yellow fever. Saboya virus (SABV) is an understudied flavivirus grouping in the same genetic sub-group as Yellow Fever Virus (YFV) together with Sepik virus (SEPV) and Wesselbron virus (WSLV). Flavivirus infections are charac…

Leveraging Lessons Learned from Yellow Fever and Polio Immunization Campaigns during COVID-19 Pandemic, Ghana, 2021.

Ghana is a yellow fever-endemic country and experienced a vaccine-derived polio outbreak in July 2019. A reactive polio vaccination campaign was conducted in September 2019 and preventive yellow fever campaign in November 2020. On March 12, 2020, Ghana confirmed its first COVID-19 cases. During February-August 2021, Ghana received 1,515,450 COVID-19 vaccines through the COVID-19 Vaccines Global Access initiative and other donor agencies. We describe how systems and infrastructure used for polio and yellow fever vaccine deployment and the lessons learned in those campaigns were used to deploy C…

Testing the genomic stability of the Brazilian yellow fever vaccine strain using next-generation sequencing data.

The live attenuated yellow fever (YF) vaccine was developed in the 1930s. Currently, the 17D and 17DD attenuated substrains are used for vaccine production. The 17D strain is used for vaccine production by several countries, while the 17DD strain is used exclusively in Brazil. The cell passages carried out through the seed-lot system of vaccine production influence the presence of quasispecies causing changes in the stability and immunogenicity of attenuated genotypes by increasing attenuation or virulence. Using next-generation sequencing, we carried out genomic characterization and genetic d…

Persistence of Neutralizing Antibody Responses Among Yellow Fever Virus 17D Vaccinees Living in a Nonendemic Setting.

BACKGROUND: The once-in-a-lifetime recommendation for vaccination against yellow fever virus (YFV) has been controversial, leading to increased scrutiny of the durability of immunity after 17D vaccination. METHODS: This is a cross-sectional analysis of 17D vaccinees living in nonendemic Portland, Oregon. Neutralization assays were used to determine YFV immunity. The relationships between 17D immunity and vaccination history, demographics, and travel were evaluated using nominal logistic regression. RESULTS: Seventy-one of 92 (77.2%) subjects were YFV seropositive (90 percent plaque reduction…

CREB-binding protein regulates metamorphosis and compound eye development in the yellow fever mosquito, Aedes aegypti.

Juvenile hormones (JH) and ecdysone coordinately regulate metamorphosis in Aedes aegypti. We studied the function of an epigenetic regulator and multifunctional transactivator, CREB binding protein (CBP) in A. aegypti. RNAi-mediated knockdown of CBP in Ae. aegypti larvae resulted in suppression of JH primary response gene, Krüppel-homolog 1 (Kr-h1), and induction of primary ecdysone response gene, E93, resulting in multiple effects including early metamorphosis, larval-pupal intermediate formation, mortality and inhibition of compound eye development. RNA sequencing identified hundreds of gene

Post-Vaccination Yellow Fever Antiserum Reduces Zika Virus in Embryoid Bodies When Placental Cells are Present.

Zika virus (ZIKV) is a flavivirus that originated in Africa but emerged in Latin America in 2015. In this region, other flaviviruses such as Dengue (DENV), West Nile, and Yellow Fever virus (YFV) also circulate, allowing for possible antigenic cross-reactivity to impact viral infections and immune responses. Studies have found antibody-mediated enhancement between DENV and ZIKV, but the impact of YFV antibodies on ZIKV infection has not been fully explored. ZIKV infections cause congenital syndromes, such as microcephaly, necessitating further research into ZIKV vertical transmission through t…

A Chimeric Japanese Encephalitis Vaccine Protects against Lethal Yellow Fever Virus Infection without Inducing Neutralizing Antibodies.

Recent outbreaks of yellow fever virus (YFV) in West Africa and Brazil resulted in rapid depletion of global vaccine emergency stockpiles and raised concerns about being unprepared against future YFV epidemics. Here we report that a live attenuated virus similar to the Japanese encephalitis virus (JEV) vaccine JE-CVax/Imojev that consists of YFV-17D vaccine from which the structural (prM/E) genes have been replaced with those of the JEV SA14-14-2 vaccine strain confers full protection in mice against lethal YFV challenge. In contrast to the YFV-17D-mediated protection against YFV, this protect…