The United States’ vaccine campaign has plummeted from its previous highs. While more than 3 million people received the shot every day in mid-April, only about 1.2 million do now — a rate that is less than half of what it was at the peak. As a result, the United States may fall short of President Joe Biden’s goal of vaccinating 70% of adults by July 4th: At current rates, approximately 175 million adults will have received their first vaccinations by Independence Day, falling short of the nearly 180 million required.

Some of these people may be persuadable, while others may not be. The most resistant are likely to be the most difficult to persuade at this point, remaining between 15 and 20% of the population from poll to poll. But, in between these hard noes and the already vaccinated, there are a lot of people who have previously shown signs of movement — enough to make a significant dent in the fight against Covid-19.

According to Kaiser Family Foundation polls, about 4% of Americans intend to get the vaccine as soon as possible but haven’t yet, and another 12% are on the fence. Access is still likely to be a major barrier, particularly among these segments of the population. True, access to the vaccine has increased dramatically in recent months, with the federal government now ordering and delivering far more doses than states actually use. A shot that once required an appointment, weeks in advance is now so common that walk-ins are welcome at many pharmacies and other locations.

However, there are still obstacles. People may not be able to get to a pharmacy because they lack transportation. A busy, rigid family or work schedule may prevent them from taking time off work to get the shot and recover from the side effects. Some people mistakenly believe — incorrectly — that getting the vaccine isn’t free for everyone, or they simply aren’t aware that the vaccine is available to them.

Some are concerned about the vaccine itself, particularly the potential side effects. These concerns may be about something the vaccine actually causes, such as aches, fever, and fatigue, or, in extremely rare cases, blood clots. However, they can also be about things that aren’t real or proven, such as other long-term health risks or unproven claims about infertility, for example. But there are also more practical considerations. Some people who are concerned about side effects may worry that a day or two of fatigue and fever will keep them from working, putting their job at risk or, at the very least, costing them money that they need to pay the bills. Fixing this will simply require more employers to provide paid time off or a pay bonus not only for getting the shot but also for the recovery period.

Aside from concerns about side effects, many of those who are hesitant simply do not have faith in vaccines. They may believe that the vaccine production process was too quick — after all, it was a record time from conception to mass production. They should be aware that the vaccines are not even officially approved by the Food and Drug Administration, as the agency has only authorized them for emergency use. Some of those who are hesitant may be concerned not so much about Covid-19 and vaccines as they are about the institutions that surround both. They may not trust the government agencies or corporations that assisted in the development of the vaccines. Alternatively, they may have a general distrust of the health-care system. Restoring trust in institutions is a lengthy and difficult process. In the meantime, approaches such as incentives and education campaigns can persuade people that, regardless of what these organizations do, it is in their best interests to get vaccinated.

According to political science research, the best hope for refuting such misinformation is for public officials and the media to stop spreading it and, when it does appear, to correct it. However, the spread of disinformation is a much more difficult problem that society as a whole is still grappling with, as the internet and social media have made it so easy for people to spread lies and myths — and it will take some time to really get a handle on this.