. Author manuscript; available in PMC: 2020 Apr 6.

Published in final edited form as: J Travel Med. 2018 Jan 1;25(1):10.1093/jtm/tay108. doi: 10.1093/jtm/tay108

Table 2.

Yellow fever neutralization titers among US travellers with one reported dose of vaccine by years post-vaccination

Years post-vaccination	Seropositive^a/tested	(%)	Geometric mean titer of reactive sera
0–4	128/136	94	298
5–9	18/19	95	84
10 −19	34/42	81	62
20–29	13/16	81	58
>30^b	7/8	88	24

Titers ≥1:10 are considered positive using plaque reduction neutralization test with 90% cutoff.

Maximum years post-vaccination was 53 years.