Researchers at UPMC Children's Hospital of Pittsburgh are working on a vaccine for the second most common virus caught by children. It's called metapneumovirus (MPV) and it hospitalized tens of thousands of children in the U.S. each year.

Creating a vaccine is a time-intensive process that takes decades on decades of researching, testing and finalizing. Vaccines must be tested in animals first and show evidence that it is safe and effective before moving on to humans. Then, a small group of adult volunteers are given the vaccine to ensure it's safe before allowing human trials for effectiveness.

MPV was only discovered in 2001, but thanks to research done on respiratory syncytial virus (RSV) a vaccine is likely to be ready in the next 10-15 years. The research on RSV shaved off between 35-40 years on developing the MPV vaccine.