This 2017 image, depicted the hands of a Centers for Disease Control and Prevention (CDC) scientist, who was unpacking influenza samples that had been sent to CDC for testing. At this point in the process, while wearing pink-colored protective gloves, the scientist was transferring the sample vials from their cold shipping box, into a black plastic vial tray, while inside a negatively-pressurized flow hood. Working within the confines of the flow hood, prevented any pathogens from escaping into the laboratory environment.
Influenza (flu) viruses change constantly. As a WHO Collaborating Center for Influenza (WHO CC) and the U.S. National Influenza Center, CDC monitors flu activity nationally and globally with other labs, looking for changes in circulating viruses. CDC monitors flu viruses because changes can impact the effectiveness of flu vaccine. When circulating viruses are substantially different from those in the vaccine, vaccine effectiveness can be reduced. If it looks like viruses are starting to change in specific ways (which can impact how well the vaccine works), this can trigger health authorities to recommend different viruses for vaccine production.
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