(Reuters) - After crushing their COVID-19 outbreaks in the spring and keeping them in check all summer, states in the U.S. Northeast are now seeing infections accelerate, with New York reporting nearly 10,000 new cases last week.
Compared with the previous seven days, new cases in New York rose 102% in the week ended Oct. 4, while new cases in Connecticut rose 61% to 1,710 and new cases in New Jersey rose 23% to 4,650, according to a Reuters analysis of state and county reports.
Graphic: Where U.S. coronavirus cases are rising and falling tmsnrt.rs/2WTOZDR
Still, the percentage of tests in the Northeast that were coming back positive for the novel coronavirus remains very low, mostly in the 1%-2% range.
The Midwest continues to deal with the highest number of new cases per capita, with North Dakota, South Dakota and Wisconsin reporting the largest number of new cases per 100,000 residents in the past two weeks.
U.S. states with the biggest COVID-19 outbreaks
Health officials have long said they were worried that colder weather -- which is now hitting the Midwest and Northeast -- would increase outbreaks as more activities move indoors.
Nationally, more than 300,000 Americans tested positive for the novel coronavirus last week, down 4% from the prior week, as total cases in the country approach 7.5 million. Some of the national decrease was due to Texas, which two weeks ago reported thousands of backlogged cases.
New cases have risen for at least two weeks in a row in 21 states, though deaths from COVID-19 have generally declined for the past seven weeks. Still, more than 5,000 lives were lost last week, and deaths are a lagging indicator that generally rises weeks after a surge in cases.
For a second week in a row, testing set a record high, with on average 935,000 tests conducted each day last week, according to data from The COVID Tracking Project, a volunteer-run effort to track the outbreak.
For the first time since mid-June, the percentage of tests that came back positive for the virus was under the 5% threshold that the World Health Organization has said is concerning.
Four states had positive rates over 20%: Idaho, Iowa, South Dakota and Wisconsin.
Graphic: Global tracker with country-by-country pages - here
Writing by Lisa Shumaker; Graphic by Chris Canipe; Editing by Tiffany Wu
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