The Centers for Disease Control and Prevention says it's using whole genome testing and on-the-ground investigation to try to determine why the current E. coli outbreak from romaine lettuce is more virulent than normal — about half of all people affected have been hospitalized .

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Data: Centers for Disease Control; Cartogram: Lazaro Gamio/Axios

What's new: The E. coli outbreak stemming from romaine lettuce grown in Yuma, Ariz., has spread to 19 states and infected at least 84 people, of whom 42 have been hospitalized with 9 suffering from the dangerous hemolytic uremic syndrome, according to a CDC update today.

Threat level: Matthew Wise, deputy branch chief of CDC's Outbreak Response, tells Axios the CDC has confirmed the pathogen is E. coli 157:H7, which is part of the Shiga toxin-producing strain, but they don't know why so many patients need to be hospitalized.

"157:H7 can be a very severe illness, but [50%] is a much higher hospitalization [rate] than we expect," Wise says. "We're doing whole genome sequencing to see if there's anything unique or unusual in this particular strain."

Benjamin Chapman, food safety specialist and associate professor of North Carolina State University, tells Axios that normally the 157:H7 has about a 25%–30% hospitalization rate. He says the higher rate now could be because the strain "picked up genes from other bacteria which cause toxins [in] us," during its normal evolutionary process.

The big question: This episode of E. coli 157:H7 is one of 7 main multistate foodborne outbreaks of E. coli and salmonella that CDC has investigated in 2018. While this appears high compared with 2017 (which had a total of 8 including listeria and cyclospora), it's too early to tell if this is a new trend for the year, Wise and Chapman both say.

  • Chapman says one reason it appears higher is that "we are getting better at connecting the dots, nationally." He says with new safety standards and systems to identify outbreaks, "food is probably safer now than it was for the last 50 years."

Looking ahead: Wise says the CDC is focused on improving via 2 programs:

  1. An increase of funds to the state health departments so they can better track, report and halt outbreaks.
  2. A transition to whole genome sequencing during outbreaks, which should enable officials to see which illness is spreading where. They've completed a similar program for listeria, and the program for salmonella and E. coli should be finished by late 2018–early 2019.

Some challenges facing the CDC:

  • New lack of cultures: Chapman says the state public health system encourages new testing called culture independent diagnostic tests (CIDTs), which can quickly identify pathogen DNA shards but uses up the stool sample that the federal investigators need to be cultured. "It's a challenge," Wise says, because clinicians want the faster CIDT results but "the whole system relies upon the health care facilities to culture the bacteria."
  • IG report: While not directly part of the CDC, the Food and Drug Administration was checked out by the Inspector General's office and its food recall program was found inefficient and ineffective.

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Natural gas pipeline project cancelled after Supreme Court victory

Photo: Rafael Henrique/SOPA Images/LightRocket via Getty Images

Dominion Energy announced Sunday it has agreed to sell its natural gas transmission and storage network to Warren Buffett's Berkshire Hathaway in a deal valued at $10 billion, including the assumption of debt.

Why it matters: The deal comes as Duke Energy Corp. and Dominion Energy announced they are canceling their plans for the $8 billion Atlantic Coast Pipeline following a Supreme Court ruling. The ruling removed major hurdles for the companies, but "recent developments have created an unacceptable layer of uncertainty and anticipated" for the project.

Trump campaign "strongly" encourages face masks at outdoor rally

Photo: Jabin Botsford/The Washington Post via Getty Images

The Trump campaign will be providing face masks and hand sanitizer for all attendees at an upcoming rally Saturday in Portsmouth, New Hampshire.

  • The campaign said in an email on Sunday that attendees are "strongly encouraged" to wear the masks.

Why it matters: The campaign's first coronavirus-era rally in Tulsa, Oklahoma, was notable for its lack of masks.

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 2 p.m. ET: 11,317,637 — Total deaths: 531,729 — Total recoveries — 6,111,910Map.
  2. U.S.: Total confirmed cases as of 2 p.m. ET: 2,852,807 — Total deaths: 129,718 — Total recoveries: 894,325 — Total tested: 34,858,427Map.
  3. States: Photos of America's pandemic July 4 ICU beds in Arizona hot spot near capacity — Houston mayor warns about hospitals
  4. Public health: U.S. coronavirus infections hit record highs for 3 straight days.
  5. Politics: Former Trump official Tom Bossert says face masks “are not enough”
  6. World: Mexican leaders call for tighter border control as infections rise in U.S.
  7. Sports: Sports return stalked by coronavirus
  8. 1 📽 thing: Drive-in movie theaters are making a comeback.