Why a Common Cold Vaccine Remains Elusive Despite Decades of Research

For many in the Northern Hemisphere, the change in season brings with it the annual onslaught of colds. While flu vaccines are common, the development of a vaccine against the common cold has proven to be remarkably difficult. The challenge lies in the vast number of viruses and variants that cause colds, including rhinoviruses, adenoviruses, and various coronaviruses. With approximately 280 different variants identified, creating a single vaccine that offers broad protection is a significant hurdle. Traditional vaccine strategies, like those used for the flu, rely on targeting the dominant circulating strains. However, this approach is less effective for the common cold, as numerous variants circulate simultaneously. Initial efforts in the 1960s and 70s to develop a cold vaccine were unsuccessful, and progress has been slow since then. Some experts question whether the effort is worthwhile, given the relatively mild and short-lived nature of most colds. Despite these challenges, some scientists are making progress. Researchers are exploring ways to prepare immune systems against cold viruses, and a team at Emory University has developed a vaccine that protects monkeys from about a third of rhinoviruses. While a widely available cold vaccine is unlikely in the next five years, researchers remain hopeful that a solution can be found. Gary McLean, a molecular immunologist at Imperial College London, is even running a trial of a potential new vaccine in people.