The invention relates to a unit dose of a dengue vaccine composition and methods and uses for preventing dengue disease and methods for stimulating an immune response to all four dengue virus serotypes in a subject or subject population. The unit dose of a dengue vaccine composition includes constructs of each dengue serotype, such as TDV-1, TDV-2, TDV-3 and TDV-4, at various concentrations in order to improve protection from dengue infection.

The present invention is directed to a method of booster vaccination and to a vaccine composition for use in such a method, for inducing in a human subject a neutralizing antibody response, wherein said subject has previously received a primary vaccination against each of serotypes 1 to 4 of dengue virus and was dengue naïve before said primary vaccination, said composition comprising a dengue antigen of at least one of serotypes 1 to 4 or a nucleic acid construct capable of expressing said antigens in the subject, wherein said booster vaccination results in a 2-fold increase in the neutralizing antibody titre against each of serotypes 1 to 4. The invention is also directed to a method of inducing in a human subject a neutralizing antibody response comprising the administration of a vaccine composition, or to a vaccine composition for use in such a method, said composition comprising a dengue antigen of each of serotypes 1 to 4, or a nucleic acid construct capable of expressing in said subject a dengue antigen of each of serotypes 1 to 4; wherein said composition is administered as a primary vaccination, followed by a booster vaccination, and wherein the human subject is initially dengue naïve.

Chimeric flaviviruses engineered to contain a reporter gene and chimeric nucleic acid molecules encoding the chimeric flaviviruses are described. The chimeric flaviviruses further include genomic non-coding regions, non-structural proteins, and at least a portion of a capsid (C) protein from West Nile virus (WNV), and premembrane (prM) and envelope (E) proteins from dengue virus (DENV). Diagnostic assays that utilize chimeric West Nile/dengue viruses are further described.

The invention relates to a unit dose of a dengue vaccine composition and methods and uses for preventing dengue disease and methods for stimulating an immune response to all four dengue virus serotypes in a subject or subject population. The unit dose of a dengue vaccine composition includes constructs of each dengue serotype, such as TDV-1, TDV-2, TDV-3 and TDV-4, at various concentrations in order to improve protection from dengue infection.

The present invention relates to vaccine compositions that are useful in a method of protecting a human subject against dengue disease.

Chimeric flaviviruses that include non-coding regions, non-structural proteins, a capsid (C) protein and a portion of a premembrane (prM) signal sequence from an attenuated or wild-type dengue serotype 2 virus (DENV-2), and a portion of a prM signal sequence, a prM protein and at least a portion of an envelope (E) protein from a Zika virus (ZIKV) are described. Also described are immunogenic compositions and methods for eliciting an immune response in a subject, such as an immune response directed against ZIKV.

Compositions for protecting subjects from diseases caused by (+) SS RNA virus are described herein. The compositions include (i) a vector containing a DNA encoding a RNA molecule of an infectious (+) SS RNA virus operably linked to a eukaryotic RNA polymerase promoter and a carrier; or (ii) (+) SS RNA viruses obtained from eukaryotic cells transfected with the vector of (i) and a carrier.

Chimeric flaviviruses that include non-coding regions, non-structural proteins, a capsid (C) protein and a portion of a premembrane (prM) signal sequence from an attenuated or wild-type dengue serotype 2 virus (DENV-2), and a portion of a prM signal sequence, a prM protein and at least a portion of an envelope (E) protein from a Zika virus (ZIKV) are described. Also described are immunogenic compositions and methods for eliciting an immune response in a subject, such as an immune response directed against ZIKV.

Embodiments herein concern compositions, methods, and uses for inducing an immune response to all four dengue virus serotypes in a child or young adult from about 1 year to about 20 years of age. Some embodiments concern compositions that can include dengue virus chimeras that, either alone or in combination with other constructs, can be used in vaccine compositions against all four dengue virus serotypes. Compositions can include constructs of more than one serotypes of dengue virus, such as dengue-1 (DEN-1) virus, dengue-2 (DEN-2) virus, dengue-3 (DEN-3) virus and/or dengue-4 (DEN-4) virus, at various concentrations or ratios to improve protection from infection in children and young adults. In certain embodiments, viruses of the formulations are limited to dengue virus serotypes. Other embodiments concern methods of administering immunogenic compositions against dengue virus that can include chimeric dengue constructs and live, attenuated dengue viruses using single, dual or other regimens.

Compositions for protecting subjects from diseases caused by (+) SS RNA virus are described herein. The compositions include (i) a vector containing a DNA encoding a RNA molecule of an infectious (+) SS RNA virus operably linked to a eukaryotic RNA polymerase promoter and a carrier; or (ii) (+) SS RNA viruses obtained from eukaryotic cells transfected with the vector of (i) and a carrier.