JUST AS the United States fell into a patchwork of pandemic responses last year, the lifesaving vaccine drive has encountered troublesome zones of indifference and resistance. President Biden’s goal of at least partial vaccination for 70 percent of Americans by July Fourth now looks to be slipping away. Even more worrisome are persistent islands of vaccine hesitancy in some states and communities that could face renewed illness in the autumn.

On Monday, Republican Gov. Phil Scott announced Vermont had become the first state to vaccinate 80 percent of those eligible with at least one dose. Vermont has given out 131,473 doses per 100,000 population. By contrast, in Mississippi only 35 percent of the overall population has received at least one dose. The Centers for Disease Control and Prevention puts the Mississippi vaccination rate at less than half that of Vermont, or 61,278 administered per 100,000.

Where vaccine coverage is strong, the pandemic is receding. In the latest seven-day rolling averages, the Associated Press notes that 10 states with the fewest new infections have all fully vaccinated above the national average of 43 percent. But eight states — Alabama, Arkansas, Hawaii, Missouri, Nevada, Texas, Utah and Wyoming — have seen infections rise from two weeks earlier, and seven of them (all but Hawaii) have vaccination rates lower than the national average. Mississippi’s rate of new infections has declined, perhaps due to natural immunity, but experts point out that antibodies from previous infections may not protect as long as vaccines.

The summer months, with more fresh air and time outdoors, also may keep infections lower. But more than a third of the U.S. population older than 12 is unvaccinated, and those people are sitting ducks for infection. The new delta variant is significantly more contagious and may lead to more severe disease than the earlier variants. The average number of people each infected person passes a virus to, if nobody were immune and no one took precautions, is known as the R-naught number. For the original virus that broke out in Wuhan, China, it was 2.4 to 2.6. According to disease modelers at Imperial College, London, the figure for the delta variant is 5 to 8. While delta currently makes up only 6 percent of U.S. infections, that proportion will certainly grow. Delta already has caused Britain to delay its reopening.

The worry is that those who are hesitating to get vaccinated now will be sickened in the fall. Unbelievably, Virginia officials say fewer than half of state troopers are vaccinated — far too few. Also, according to tracking by the Kaiser Family Foundation, although racial disparities have narrowed since March, Black and Hispanic people have received smaller shares of vaccinations compared with their number of cases and their share of total population, and for Blacks, with their share of deaths. These are islands of vulnerability that no one should be willing to tolerate.

The announcement that a new two-dose vaccine in the United States, developed by Novavax, is 90 percent effective in a large-scale clinical trial is a reason for hope. But to get from hope to results requires getting doses from vials into arms.

Read more: