JACKSON, Miss. — New COVID-19 cases are declining in much of the country, even as some states have vaccine-hesitant populations. But vaccination rates driving that trend are lower than average in nearly all states, and experts warn that relief from the pandemic could be fleeting in areas where few people get vaccinated.
Case totals nationally have fallen from a seven-day average of nearly 21,000 on May 29 to 14,315 on Saturday, according to data from Johns Hopkins University. For weeks, states and cities have been dropping virus restrictions and mask mandates even indoors.
Experts said some states are seeing increased immunity because of high rates of natural spread of the disease, which has killed nearly 600,000 Americans so far.
“We’re certainly getting some population benefit from our past cases, but we paid for it,” said Mississippi state health official Dr. Thomas Dobbs. “We paid for it with deaths.”
More than 7,300 Mississippi people have died in the pandemic, and the state has the sixth-highest per capita death rate.
Dobbs estimated that about 60% of the state’s residents have “some built-in immunity.”
“So now we’re seeing that effect, most likely, because we have a combination of natural and vaccine-induced immunity,” Dobbs said.
According to data compiled by Johns Hopkins University, just eight states – Alabama, Arkansas, Hawaii, Missouri, Nevada, Texas, Utah and Wyoming – have seen their seven-day rolling averages rise in infection rates two weeks ago. According to the US Centers for Disease Control and Prevention, all of them except Hawaii have recorded vaccination rates that are lower than the US average of 39.7% for fully vaccinated.
The 10 states with the fewest new cases per capita in that time frame have outright vaccination rates above the national average. This includes the three most vaccinated states in the country: Vermont, Massachusetts, and Connecticut.
“Just because we’re lucky in June doesn’t mean we’ll be lucky in late fall and winter as well,” said Wayne, a former Baltimore city health commissioner. “We may have variants that are more transmissible, more virulent, and those who don’t have immunity or have low immunity may be susceptible once again.”
In Mississippi, approximately 835,000 people have been fully vaccinated, or 28% of the population, compared to the national average of 43%. But despite the lagging vaccination rate, the state’s rolling average of daily new cases has decreased by about 18% over the past two weeks, according to Johns Hopkins.
Dr. Albert Ko, who chairs the epidemiology department of microbial diseases at Yale, said there is no accurate data to show what percentage of the population was exposed to the virus in “high-burden” states such as Alabama or Texas. but he said estimates put it up to 50%.
“I think this doesn’t deny the importance of vaccination, especially because the levels of antibodies that you get from a natural infection are lower than with our best vaccines,” Ko said.
Ko said it is important that even those exposed to the disease are vaccinated because natural immunity does not last until vaccine immunity and antibody levels are low.
Wayne said the research strongly suggests that vaccination offers benefits to people who already have certain antibodies to the infection causing it.
“I think it’s a fallacy that a lot of people who have recovery means they no longer need vaccinations,” she said.
Pat Eaton-Robb contributed to this Connecticut report.