Puerto Rico under hurricane watch as Tropical Storm Dorian nears

• The emergency declaration will allow for the activation of Puerto Rico's National Guard, while an order freezing prices, including fuel, which Garced signed to "prevent profiteering," Deibert reports.

The big picture: Dorian became on Saturday the 4th tropical storm to form during this year’s Atlantic hurricane season. The storm has already caused power outages and brought down trees in Barbados and St. Lucia, per AP.

• The National Weather Service tweeted on Wednesday morning that hurrican watches had also been issued for Vieques, Culebra and the U. S. Virgin Islands.
• Authorities in Puerto Rico have closed schools early and prepared emergency shelter for tens of thousands of people ahead of Dorian's arrival, the New York Times reports.

What they're saying: Garced told a news conference she's "confident that the people of Puerto Rico are prepared," per the NYT.

• San Juan Mayor Carmen Yulín Cruz told CNN that Puerto Rico's capital was much better prepared than when Maria struck in 2017.

Editor's note: This article has been updated with the latest on Dorian.

Go deeper: The Atlantic Basin's tropical storms and hurricanes in 2019

Yes, but: Spacewalks are notorious for their complexity, so it's still possible that Koch and Meir's walk could change or be cancelled if something unexpected happens between now and October 21.

Details: The spacewalk is 1 of 5 planned to swap out batteries, with 5 others planned for later in the year to repair an astrophysics instrument on the outside of the station.

• The first spacewalk in the series is scheduled for Sunday. Koch and NASA astronaut Andrew Morgan are expected to start the walk at 7:50 a.m. ET.

Background: The spacewalk comes after NASA canceled an all-female spacewalk in March due to spacesuit availability.

• That particular issue shouldn't be a problem this time, however, with two spacesuits configured for use by the women.

The latest: New York's health commissioner announced Thursday morning that "there are no longer any active cases in New York State associated with the initial measles outbreak from October 2018."

• But the commissioner added that New York health officials remain "vigilant" and are currently investigating several other new cases that are unrelated to the outbreak that just ended.
• 1 of the new cases is a person who just returned from overseas to Rockland County, which had declared in September that its initial outbreak had officially ended. Because this new case was "imported" from someone traveling in another country, this is not considered to be part of the same outbreak.
• Several other New York cases were reported in Nassau (2), Monroe (2) and Putnam (1) counties, according to the health commissioner.
• Meanwhile, the CDC says 31 states reported 1,243 individual patients, 131 of whom were hospitalized and 65 of whom suffered complications, including pneumonia and encephalitis. No one died in the U.S.

"The end of the New York state measles outbreak is a credit to the great work by local and state health departments, community and religious leaders, and other partners. However, this outbreak is a grave reminder that we need heightened vigilance around measles as well as other vaccine preventable diseases, and we continue to address the myths and misinformation driving these outbreaks."

What they're saying: Peter Hotez, professor of pediatrics and dean of the National School of Tropical Medicine at Baylor College of Medicine, tells Axios that America's measles elimination status isn't as important as "the fact that we remain highly vulnerable" for 2 reasons.

1. There are "at least 100 geographic pockets in the U.S. where a high percentage of kids are not being vaccinated, together with measles cases now regularly imported from Europe where measles is even more widespread," Hotez says.
2. During the first and second quarter of next year, "we’ll again hit peak measles transmission season. [The] bottom line [is] nothing has really been done to combat the anti-vaccine movement in America, and we’re just as vulnerable to measles epidemics as we were this time last year."

What's next: The CDC and the Department of Health and Human Services are expected to have further information on the measles outbreak on Friday.

• The Pan American Health Organization’s regional verification commission will meet in the coming months to look over the U.S. data from this year and likely 2018 to make the final determination on the U.S.' elimination status, the CDC spokesperson said.
• PAHO declared recently that the U.K., Albania, the Czech Republic and Greece had lost their measles-free status.

Go deeper:

• Anti-vax movement targets Maine law on vaccine exemptions
• New measles cases decline in U.S., but the outbreak isn't over yet
• Measles in U.S. creeps back toward endemic status

Details: In the letter published Oct. 2 in the New England Journal of Medicine, researchers reviewed lung biopsies from 17 patients, "all of whom had vaped and were suspected to have vaping-associated lung injury," the Mayo Clinic said.

• Lipids, fatty substances found in mineral oils were suspected as a possible cause of the lung injuries associated with vaping, but the researchers in this study found no evidence of this causing the tissue injury.

"While we can't discount the potential role of lipids, we have not seen anything to suggest this is a problem caused by lipid accumulation in the lungs. Instead, it seems to be some kind of direct chemical injury, similar to what one might see with exposures to toxic chemical fumes, poisonous gases and toxic agent."

Go deeper: U.S. investigates fatality from vaping as lung-related illnesses rise