The initial objective of ZIKV-001 was to determine if macaques could be infected with Asian-lineage Zika virus. We quickly learned that they could. A secondary objective was to learn whether immune responses elicited by primary infection protect against subsequent reinfection. This asks the question - once you've been infected with Zika virus, can you be infected again? So if a woman is infected as a child, can she be reinfected during pregnancy?
Last week we rechallenged all three ZIKV-001 macaques to ask this question. None of the animals have had detectable plasma viremia in the four days since rechallenge. This indicates that immunity to primary Zika virus infection protects from reinfection.
We do not know yet how long it takes for a protective immune response to develop or whether this happens in every case. But at least in the three animals tested here, there is apparent sterilizing immunity from reinfection.
I'm now following Dr. O'Connor, and the Zika Open-Research Portal is going in the Chikungunya, Dengue, Zika Resources list.