Vaccines

An outbreak of H5N1 avian influenza that started in 2021 has become the largest bird flu outbreak in history, both in the U.S. and worldwide. In the U.S. the virus has led to the destruction of millions of commercially raised chickens, turkeys, ducks and geese, and has killed thousands of wild birds. Many virologists are concerned that this virus could spill over to humans and cause a new human pandemic. University of Colorado Boulder virologists Sara Sawyer, Emma Worden-Sapper and Sharon Wu summarize the compelling story of H5N1 and why scientists are closely watching the outbreak. 1. Is this virus a serious threat to humans? H5N1 is a specific type of influenza virus, predominantly harbored by birds, that was first detected on a goose farm in China in 1996. Recently it has begun infecting an exploding diversity of bird and mammalian species around the globe. The virus is highly pathogenic to birds, meaning that infections often cause extreme symptoms, including death. But...

Honeybees, which pollinate one-third of the crops Americans eat, face many threats, including infectious diseases. On Jan. 4, 2023, a Georgia biotechnology company called Dalan Animal Health announced that it had received a conditional license from the U.S. Department of Agriculture for a vaccine designed to protect honeybees against American foulbrood, a highly destructive infection. To receive a conditional license, which usually lasts for one year and is subject to further evaluation by the USDA, veterinary biological products must be shown to be pure, safe and reasonably likely to be effective. Dr. Jennie Durant, an agriculture researcher at the University of California, Davis, who specializes in honeybee health, explains why this vaccine is potentially an important step in ongoing efforts to protect pollinators. 1. What threat does this vaccine address? The new bee vaccine, Paenibacillus Larvae Bacterin, aims to protect honeybees from American foulbrood. This highly destr...

At TED2015, Seth Berkley showed two Ebola vaccines under review at the time. One of these vaccines is now being deployed in the current Ebola outbreak in the DRC. Photo: Bret Hartman/TED

When the COVID-19 pandemic first emerged, many wildlife disease researchers like me were not too surprised. Some were intrigued it hadn’t happened sooner; after all, it is our job to observe, describe and study pandemic dynamics in animals. Amphibians, for example, have been undergoing a global panzootic – the animal version of a pandemic – for decades. In the late 1990s, researchers identified the amphibian chytrid fungus, which causes the often-lethal disease chytridiomycosis, as the probable culprit behind frog and salamander declines and extinctions from Australia to Central America and elsewhere that began 10, 20 or even 30 years before. Scientists have found this pathogen on every continent that amphibians inhabit, and the extensive global amphibian trade has likely spread highly lethal strains around the world. The amphibian chytrid fungus is widespread in some geographic regions, and, like the virus that causes COVID-19, it can mutate rapidly and take n...