High demand for the shingles vaccine means Pennsylvanians wanting to protect themselves against the painful, blister-causing virus might have to wait. “The demand has been unprecedented,” said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security and a Pittsburgh-based infectious disease physician. “We want to have demand like this for every vaccine.” Shingles is caused by the same virus that causes chickenpox. Anyone who’s had chickenpox may develop shingles, which causes a stripe of blisters on the torso. Of the two vaccines on the market, Shingrix, which was approved in 2017, is deemed most protective. Manufactured by GlaxoSmithKline, or GSK, it is a two-dose series recommended for people 50 and above. The other vaccine, produced by Merck, is recommended for those aged 60 and older. With a shingles vaccine now recommended for a greater number of Americans, more, apparently, are looking for protection against the virus, Adalja said. Roughly one in three Americans will develop shingles their lifetime, according to the Centers for Disease Control and Prevention. An estimated 1 million people get shingles every year. About 1% to 4% of those who get shingles are hospitalized for complications. In the months after contracting shingles, patients are at a greater risk for heart attack and stroke. “It is difficult to quantify the shortage, or how long people will have to wait,” said Nate Wardle, a Pennsylvania Department of Health spokesman. “For some, there may not be any wait at all.” Consumer Reports reported earlier this year that GlaxoSmithKline delivered 8.3 million doses of Shingrix in 2018. Sean Clements, a GSK spokesman, could not be immediately reached for comment. The health department recommends that people use the online vaccine locator — see Shingrix.com — or call their family doctor or pharmacy to see if the vaccine is in stock. Email Newsletters TribLIVE's Daily and Weekly email newsletters deliver the news you want and information you need, right to your inbox.