Nature
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The 2002-3 pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV) was one of the most significant public health events in recent history. An ongoing outbreak of Middle East respiratory syndrome coronavirus suggests that this group of viruses remains a key threat and that their distribution is wider than previously recognized. Although bats have been suggested to be the natural reservoirs of both viruses, attempts to isolate the progenitor virus of SARS-CoV from bats have been unsuccessful. ⋯ Preliminary in vitro testing indicates that WIV1 also has a broad species tropism. Our results provide the strongest evidence to date that Chinese horseshoe bats are natural reservoirs of SARS-CoV, and that intermediate hosts may not be necessary for direct human infection by some bat SL-CoVs. They also highlight the importance of pathogen-discovery programs targeting high-risk wildlife groups in emerging disease hotspots as a strategy for pandemic preparedness.
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Neutralizing antibodies can confer immunity to primate lentiviruses by blocking infection in macaque models of AIDS. However, earlier studies of anti-human immunodeficiency virus type 1 (HIV-1) neutralizing antibodies administered to infected individuals or humanized mice reported poor control of virus replication and the rapid emergence of resistant variants. A new generation of anti-HIV-1 monoclonal antibodies, possessing extraordinary potency and breadth of neutralizing activity, has recently been isolated from infected individuals. ⋯ When administered together, a single treatment rapidly suppressed plasma viraemia for 3-5 weeks in some long-term chronically SHIV-infected animals with low CD4(+) T-cell levels. A second cycle of anti-HIV-1 monoclonal antibody therapy, administered to two previously treated animals, successfully controlled virus rebound. These results indicate that immunotherapy or a combination of immunotherapy plus conventional antiretroviral drugs might be useful as a treatment for chronically HIV-1-infected individuals experiencing immune dysfunction.