Cross-clade vaccination to overcome sarbecovirus or merbecovirus neutralization gaps.

The coronavirus disease 2019 (COVID-19) pandemic highlights the importance of identifying high risk pathogens, defining the immunity gaps and developing preemptive vaccination strategies. Here, we establish a high-resolution surrogate virus neutralization test detecting neutralizing antibodies against multiple virus families simultaneously, demonstrating good concordance with traditional assays. Extensive serosurveillance of pre-pandemic sera from different continents reveals low prevalence human exposures to different beta-coronaviruses, and identifies individuals with prior exposure to ACE2-binding MERS-like viruses. Furthermore, COVID-19 vaccination induces significant cross-neutralizing antibodies against clade 1b, 1c, and 3 but not clade 1a sarbecoviruses. Similarly, MERS and Nipah convalescent sera neutralize cognate viruses but have limited cross-neutralization against other related merbecoviruses and henipaviruses that utilize DPP4 and ephrin B2 receptors. Finally, a cross-clade prime-and-boost vaccination strategy using antigenically distinct antigens could induce broadly neutralizing antibodies against related viruses beyond vaccine antigens, supporting broad-spectrum beta coronavirus vaccine development.