Table 2 Results from vaccinations of two varieties of commercial chickens with inactivated vaccines against homologous and heterologous HPAI.

From: Protection of layers and breeders against homologous or heterologous HPAIv by vaccines from Korean national antigen bank

Chicken species (age)

Vaccine strain (antigen dosea)

Challenge Strainb

Survival (%) (MDT)c

Peak shedding (3 dpi)d

HI titer (log2)e

OP

CL

Pre-challenge

Post-challenge

Layer chickens (35w)

rgKA435/2.3.2.1c (one dose)

KA435

100 (−)

3/10 (0.4)

2/10 (0.4)

10/10(7.0)

10/10(9.5)

ES2

70 (6.3)

4/10 (0.7)

1/10 (0.4)

10/10(2.4)

7/7(5.9)

Sham

KA435

0 (3.2)

5/6 (3.2)

3/6 (2.5)

0/10(−)

0/0(−)

rgES2/2.3.4.4c (one dose)

ES2

100 (−)

1/10 (0.2)

1/10 (0.1)

10/10(7.2)

10/10(8.7)

KA435

80 (8.5)

2/10 (0.3)

0/10 (−)

10/10(2.3)

8/8(5.6)

Sham

ES2

0 (4.0)

3/4 (1.4)

3/4 (2.7)

0/10(−)

0/0(−)

Breeder chickens (35w)

rgKA435/2.3.2.1c (one dose)

KA435

100 (−)

1/8 (0.2)

0/8 (−)

8/8(7.1)

8/8(8.6)

ES2

62.5 (4.7)

7/8 (1.3)

3/8 (0.7)

8/8(3.4)

5/5(6.4)

Sham

KA435

0 (3.4)

3/3 (3.7)

3/3 (3.3)

0/8(−)

0/0(−)

rgES2/2.3.4.4c (one dose)

ES2

100 (−)

2/8 (0.3)

0/8 (−)

8/8(7.3)

8/8(8.6)

KA435

75 (7.0)

7/8 (1.5)

1/8 (0.2)

8/8(3.1)

6/6(7.3)

Sham

ES2

100

3/4 (2.9)

3/4 (1.4)

0/8(−)

0/0(−)

  1. aOne dose (1) contained 512 HAU (hemagglutination units).
  2. bHomologous: same as vaccine strain; heterologous: different from vaccine strain.
  3. cMDT = mean death time (days).
  4. dNo. virus positive/total in group (mean shed-virus titer).
  5. eNo. serology positive/total survived in group (mean HI titer).
  6. No. of commercial chickens: 10 layer chickens per group; 8 breeder chickens per group
  7. Abbreviations: EID50, 50% egg infectious dose; HA, hemagglutination activity; NT, not tested; dpi, days post-infection; OP, oropharyngeal; CL, cloacal; HI, hemagglutination inhibition; PD50, 50% protective dose.
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