Has the Johnson & Johnson vaccine missed a critical moment?
 Watch Video: FDA extends Johnson & Johnson COVID vaccine expiration date  Amid a months-long decline in daily vaccinations across the U.S., pitfalls in the rollout of Johnson & Johnsons one-dose vaccine have resulted in millions of unused doses, public skepticism and a diminished role in the nations vaccine rollout. Johnson & Johnson had aimed to deliver 100 million doses of vaccine to states by the end of May, but fewer than 22 million have been shipped to states so far, according to data from the CDC. The shot currently makes up less than 4% of doses administered nationwide. In Washington state, the lack of supply has diminished plans to target harder-to-reach communities with the shot and incorporate the vaccine in the states larger rollout, said Dr. Umair Shah, the states Secretary of Health. There have been interruptions, there have been concerns, and theres even been the pause, he said. And because of that, it has at times really not lived up to that promise that we all would have liked here for the J&J vaccine.  The shortage is due at least in part to the major setback the company faced at the end of March when it disclosed that a batch of materials for its vaccine had to be discarded. Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases, told CBS This Morning that human error had contaminated and ruined 15 million doses at the Emergent BioSolutions plant in Maryland, forcing regulators to halt the production process. On Friday, the FDA authorized the use of two batches of vaccine drug substances manufactured at the Emergent plant. A source told CBS News that the authorization would free up approximately 10 million doses for use in the U.S. and abroad. The East Baltimore facility is one of three sites worldwide being used by Johnson & Johnson for the first step of its vaccine production. The exterior view of the Emergent BioSolutions plant on April 01, 2021 in Baltimore, Maryland. Tasos Katopodis / Getty Images  State and federal health officials have also had to confront public hesitancy on two fronts: effectiveness and safety. The company posted lower overall efficacy rates compared to the two mRNA candidates, Pfizer and Moderna, even though all three vaccines successfully protect against severe illness and death. It was set back further after the CDC and FDA paused use of the vaccine while a federal advisory board investigated cases of rare blood clots that occurred primarily among women under 50. Ultimately, after 10 days, the panel reaffirmed its recommendation for use by anyone 18 or older, with a warning added to the vaccines label. Despite health officials backing the safety and efficacy of the vaccine, polling suggests the message may not have resonated, especially among those who were already hesitant about the vaccines. Polling from the Kaiser Family Foundation in March found more than 50% of unvaccinated Americans who said they would prefer to wait and see how others reacted to the vaccine before getting one said they would definitely or probably get the Johnson and Johnson vaccine. But in April, following the pause, only 28% of people in that category said they were very or somewhat confident in the vaccines safety. Dr. Grace Lee, who is both a member of the CDC advisory panel that assessed the safety of the vaccine as well as chair of a workgroup within the federal advisory board, acknowledged that any pause on a vaccine will likely raise questions about its safety. But she echoed a response repeated by health officials nationwide: that diligent oversight should engender trust. Its less about the information of any particular vaccine, its really how we handle the decision-making around it, she said. Over the last few weeks, representatives of the Association of State and Territorial Health Officials (ASTHO) have been in discussions with the CDC and the White House after learning member states had shelved vaccine doses, particularly Johnson & Johnson doses, that were nearing expiration, Dr. Nirav Shah, the organizations president and director of the Maine Centers for Disease Control and Prevention told CBS News. The organization sent a list of policy considerations for the administration to consider, including sending those doses abroad and working with the FDA to extend the expiration date of the vaccine. On Thursday, Johnson & Johnson announced that it had extended the shelf-life of the vaccine by 50%, from three months to four and a half. A source familiar with the matter told CBS News before the decision that hundreds of thousands of doses were nearing expiration. While other states consider their options with J&J doses they dont expect to use, Dr. Umair Shah expressed both optimism and hesitancy at future use. What I worry about is, has the time that really could have helped us with the J&J vaccine already somewhat passed? he said. In a statement, the company said it remained committed to helping end this deadly pandemic as quickly as possible.  We continue to work with the U.S. government and health authorities to support the use of our vaccine, which continues to play an important role, including among those who wish to be fully vaccinated with one shot.  Boxes of the Covid-19 Johnson & Johnson Janssen vaccine are ready to be distributed as part of a collaborative effort from the West Virginia National Guard, FamilyCare Health Centers and Toyota to vaccinate Toyota employees on March 26, 2021 on the grounds of the Toyota plant in Buffalo, West Virginia. STEPHEN ZENNER / Getty Images  Although the time for the vaccine to make its largest dent may have come and gone, it remains crucial in some circumstances, including in settings where it would be difficult to schedule a second dose. One CDC poll conducted in April during the pause found that more than 50% of U.S. states and territories were using the J&J vaccine to inoculate individuals experiencing homelessness, people behind bars and those who are unable to leave their homes. Dr. Nirav Shah says his state continues to see strong demand for the shots via mobile vaccination units. His strategy to maintain its use has been to maximize convenience and provide an on-site doctor to answer patients questions. Of course that is more intensive, its not 1,000 or 3,000 people a day, thats okay, it doesnt need to be, he said during an interview last month. But I think that is the key for those folks who are either motivated by convenience.or have earnest questions.  Elsewhere around the country, convenience is being prioritized, including in northwestern Indiana, where Beth Wrobel, CEO of HealthLinc, a local community health center, says her team has used the J&J vaccine at vaccine events with about 10 different manufacturing sites in the area. Tom Dermody, Mayor of La Porte, Indiana, who partnered with the clinic to administer vaccines in the town, said for some, the one-dose vaccine remains ideal. But both officials made it clear that demand has undeniably decreased. Dr. Umair Shah stressed that as the pool of unvaccinated individuals eager to get the shot continues to dwindle, J&Js vaccine remains an attractive option for those who face more barriers to vaccination. This is where a one-shot vaccine is going to be very helpful, it just wouldve been more helpful if we couldve had it all along, he said. Alexander Tin contributed reporting.