NEW YORK (NYTIMES) - The reopening and relaxing of social distancing restrictions in some states may be contributing to the first noticeable nationwide increase in coronavirus fatalities since April, when the pandemic initially peaked.

The number of cases in late June surged higher than during the outbreak's first peak. At this same time, daily Covid-19 fatalities decreased slightly, leading President Donald Trump to proclaim that deaths were "way down". But that divergence may have come to an end two weeks ago, when the average number of new deaths per day began steadily rising again.

Public health experts have pointed to a few factors that help explain why the death count was initially flat. Treatment has improved and young people, who are less likely to die from Covid-19, make up a larger share of new cases.

Additionally, more widespread testing means cases are caught sooner, on average. That means that the lag between diagnosis and death would be longer than in March, when tests were in critically short supply.

That lag may have come to an end two weeks ago, as the number of new deaths began to rise. Many of the states that reopened early are the ones seeing the biggest increases, while New York, the country's hardest-hit city, has seen a 64 per cent drop since June 1.

While the growth rate of new deaths has flattened slightly in the past week, data suggest that the recent increase in deaths could continue. Most of the states seeing the sharpest increase in deaths also have some of the country's highest positive test rates, as well as soaring hospitalisation rates, an indicator that many more residents may be gravely ill.

In addition, a high share of positive tests most likely signals that there are a larger number of people whose infections are going undetected in a state's official numbers.