NEW YORK (NYTIMES) The overall rate of Covid-19 deaths has declined since vaccines became widely available in April, yet nearly a quarter of a million people in the United States have died from the virus in the past eight months. The virus is now responsible for a higher share of deaths from all causes for younger Americans and white Americans than it was before all adults were eligible for vaccines.

Covid-19 accounted for 14 per cent of all deaths in the US from March last year until all adults became eligible for the vaccine in April, compared with 11 per cent of deaths since then.

And while for much of the pandemic, older Americans and people of colour were more likely to die from the virus, the demographics of those dying from Covid-19 have shifted, too, according to data from the Centres for Disease Control and Prevention (CDC).

How the arrival of the highly transmissible Omicron variant will affect these trends remains to be seen, since the current data on deaths is reliable only through late November.

Scientists are still hopeful that vaccines - and especially booster shots - will stave off Omicron's worst effects.

Covid-19 has been particularly deadly for older people, but that group was also among the first to be eligible for vaccines. Now, people 65 and older have the highest vaccination rate, with nearly 90 per cent of them fully vaccinated.

The higher vaccination rate for older people has helped to protect them. Although more older than younger people still die from Covid-19, the virus is now responsible for a smaller share of all deaths among people 65 and older than it was before vaccines became available to all adults.

For those younger than 65, Covid-19 has risen as a cause of death.

The change in death rates among groups is starker by race and ethnicity, and the death rate has risen particularly sharply for middle-aged white people.

Covid-19 now accounts for a much larger share of all deaths for that group than it did before vaccines were widely available.

Some of the shift could be attributed to the lagging vaccination rates among white people overall.

White people were vaccinated at a higher rate than Black and Hispanic people in the early months of the vaccination campaign - in part because people of colour faced more obstacles to vaccine access.

In recent months, however, data from the CDC shows that the vaccination gap has narrowed. White people are now less likely than Asians and Hispanics to be vaccinated, though somewhat more likely than Black people, and their death rates have risen in all but the oldest age groups.

Younger people from all groups likewise have been vaccinated at lower rates, and children five and up have been eligible for vaccines only since early November.

Where people are dying of Covid-19 also has changed since vaccines became widely available. Death rates fell in most counties across the country, and in about one in five counties, the death rate fell by more than half.

But in about one in 10 counties, death rates have more than doubled.

In the early months of the pandemic, deaths were highest in the North-east, including in New York City and in other urban areas.

Now they are spread across the country. Many places that were spared in the first year of the pandemic have not been able to maintain their low death rates.

Places like Mississippi and Alabama saw death rates fall, but their rates remain higher overall than in places like Vermont and Maine, which saw rates increase but remain low.

States with lower vaccination rates tend to have had higher Covid-19 death rates, particularly from the most recent wave of Delta variant infections, which hit the South the hardest.

This all suggests that the change in who is dying from Covid-19 may be tied to which areas experienced the worst outbreaks of the Delta variant and who in those areas remains unvaccinated.

Relaxed precautions in many areas may also play a role.

When vaccination rates and behaviour changes are not enough to stop the virus from spreading, those infections are much more likely to lead to hospitalisation and death for unvaccinated people.

The latest data from the CDC, which is based on data from 25 states and cities, shows that the death rate for unvaccinated people is 14 times as high as that for vaccinated people.

And Omicron is now causing a surge in coronavirus cases, even in highly vaccinated places.

Although preliminary studies abroad suggest that infections from the variant could be milder, scientists caution that it is too soon to tell how deadly it will be or for whom.