An isolated polynucleotide comprising: a first nucleotide sequence encoding a first antigenic polypeptide, wherein the first antigenic polypeptide: a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 29; b. is capable of initiating an immune response to the first oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; and a second nucleotide sequence encoding a second antigenic polypeptide, wherein the second antigenic polypeptide: a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 30; b. is capable of initiating an immune response to the second oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; wherein the first antigenic polypeptide has the following mutations relative to SEQ ID NO: 2: a. a point mutation or deletion at L50; b. a point mutation or deletion at E148; c. a point mutation or deletion at T149; d. a point mutation or deletion at Q150; and e. a point mutation or deletion at L151; and wherein the second antigenic polypeptide has the following mutations relative to SEQ ID NO: 4: a. a point mutation or deletion at H2; b. a point mutation or deletion at C24; c. a point mutation or deletion at E46; and d. a point mutation or deletion at L67. a first nucleotide sequence encoding a first antigenic polypeptide, wherein the first antigenic polypeptide: a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 29; b. is capable of initiating an immune response to the first oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; and a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 29; b. is capable of initiating an immune response to the first oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; a second nucleotide sequence encoding a second antigenic polypeptide, wherein the second antigenic polypeptide: a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 30; b. is capable of initiating an immune response to the second oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; a. comprises an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 30; b. is capable of initiating an immune response to the second oncogenic viral polypeptide in an immune-competent host; and c. is non-oncogenic in the immune-competent host; wherein the first antigenic polypeptide has the following mutations relative to SEQ ID NO: 2: a. a point mutation or deletion at L50; b. a point mutation or deletion at E148; c. a point mutation or deletion at T149; d. a point mutation or deletion at Q150; and e. a point mutation or deletion at L151; a. a point mutation or deletion at L50; b. a point mutation or deletion at E148; c. a point mutation or deletion at T149; d. a point mutation or deletion at Q150; and e. a point mutation or deletion at L151; and wherein the second antigenic polypeptide has the following mutations relative to SEQ ID NO: 4: a. a point mutation or deletion at H2; b. a point mutation or deletion at C24; c. a point mutation or deletion at E46; and d. a point mutation or deletion at L67. a. a point mutation or deletion at H2; b. a point mutation or deletion at C24; c. a point mutation or deletion at E46; and d. a point mutation or deletion at L67.