Measles — declared eradicated in the U.S. in 2000 — has roared back at a record pace this year, reaching the highest number in a single year.

And it's only April 25.

Why it matters: Most Americans have no firsthand experience with measles and that lack of familiarity, along with the online success of the anti-vaccine movement, is giving a deadly but easily preventable virus an opening to spread.

So far in 2019, there have been:

• 695 confirmed cases of measles in 22 states.
• More than 71 new confirmed cases reported in just the past week.
• 5 states reporting ongoing outbreaks as of Monday (at least 3 cases in one place counts as an outbreak).

We may be a victim of of own success in squelching what used to be a ubiquitous virus that is extremely contagious.

• According to the CDC, prior to 1963, between 3 and 4 million were infected each year and nearly all children got measles by the time they were 15 years old.
• A CDC spokesperson tells Axios that among reported cases, an estimated 400 to 500 people died annually prior to widespread vaccination, 48,000 were hospitalized, and 1,000 suffered encephalitis (swelling of the brain) from measles.

Now, due in large part to vaccination efforts that began in 1963, most Americans have no experience with the virus.

• Parents may be fooled into thinking that measles is a relatively mild disease, similar to the flu, and think vaccination is optional or not a priority.
• This is not only wrong, but it could have deadly consequences.

"Parents may think that many vaccine-preventable diseases are mild, but there’s no way to tell how serious a disease may be for a child," CDC spokesman Jason McDonald tells Axios via email. Measles can be particularly hazardous for babies and young children, he says.

• From 2001 to 2013, 28% of children younger than 5 years old who had measles had to be treated in the hospital, McDonald said, referring to relatively small outbreaks related to patients who traveled to the U.S. from regions where the disease is still active.
• "Some children develop pneumonia (a serious lung infection) or lifelong brain damage."

Different vaccine hesitant communities added together are causing vaccination rates to fall below effective immunity levels, Anthony Fauci, who leads the National Institutes of Allergy and Infectious Diseases, tells Axios.

The CDC issued a stark warning Wednesday: "The longer these outbreaks continue, the greater the chance measles will again get a sustained foothold in the United States."

What to watch: The widely reported health impacts from the ongoing outbreaks, including children in intensive care units and an El Al Airlines flight attendant in a coma, may spur people to be vaccinated.

“I think unfortunately the best motivation… is that we’re having these outbreaks and people are really getting seriously ill,” Fauci says. “Those are the things that are going to jolt people into reconsidering this.”

Go deeper:

• U.S. measles cases hit highest level since it was declared eradicated in 2000
• U.S. measles cases are "accelerating" amid "global crisis"
• YouTube let extremist content flourish despite warnings
• "This is a very dangerous situation": Experts sound alarm on measles

Scientists have developed a tool that decodes brain signals for speech-related movements of the jaw, larynx, lips and tongue and synthesizes the signals into computerized speech, according to a new study published in Nature, Eileen Drage O'Reilly writes.

Why it matters: This study offers a proof-of-concept on a new and faster way of helping people who've lost their ability to speak, but also comes with its own caveats, like the need to place electrodes directly on the brain.

Background: Humans' natural speech averages around 120–150 words per minute.

• Typing controlled by the eyes or cheek can only translate an average of 10 words per minute.
• Brain-computer interfaces (BCIs) for communications can be non-invasive, often using EEG or MEG imaging devices to measure electrical activity and artificial intelligence to translate them.

Yes, but: Non-invasive tools have captured the imagination, but haven't seen much success. Invasive interfaces, such as those that surgically place recording electrodes or insert tiny electrodes in the cerebral cortex, have shown more promise.

What they did: For the Nature study, the authors selected 5 patients undergoing epilepsy surgery and placed a grid of electrodes on the brain surface.

• They focused on the regions of the brain responsible for vocal tract movement.
• The patients read aloud hundreds of sentences.
• Simultaneously, those brain signals were sent to the AI program that decodes the vocal-tract movements and another that synthesizes speech and "speaks" the words.
• 1,755 English-speaking volunteers listened to blocks of the AI-generated words to get a sense of how well the virtual vocal cord translation went.

What they found:

• For sentences that were vocalized, about 70% of words were correctly transcribed, says study author Josh Chartier, a UC San Francisco bioengineering graduate student.
• Speech synthesis was also possible when volunteers mimed their sentences — but showed less accuracy.

What they're saying: Researchers are making exciting progress but remain in the very early stages, experts say.

• "This algorithm learns to decode by having examples of the person speaking while their brain is recorded. But if a person came into the lab, already paralyzed and unable to speak, there would be nothing for the algorithm to learn from. This is the biggest challenge the field faces," Matt Goldrick of Northwestern University, who was not involved in the new study, says.

A rare, long-term record of Greenland ice melt reveals the world's largest island shed ice nearly 6 times faster in the past decade when compared to the 1980s, an increase that is already contributing to sea level rise and altered ocean currents, a new study finds.

Why it matters: Greenland's fate will help determine the future viability of coastal megacities around the world, from New York to Shanghai, as sea levels rise in response to added freshwater.

What they did: For the study, published in Proceedings of the National Academy of Sciences, researchers compared data on the discharge of glacial ice into the ocean from 260 glaciers with the accumulation of snow in the interior of the island, as gathered from regional climate models.

What they found: The acceleration of Greenland's melt, which is happening due to warming air and ocean temperatures, has contributed nearly 14 millimeters in global sea level rise since 1972.

• Half of this increase has occurred in just the past 8 years.
• The Greenland Ice Sheet shed mass every year since 1998, even when the summer was relatively cool and inland snowfall was above average.
• Relatively cool summers can slow surface melt, but don't stop fast-moving glaciers from flowing into the sea.
• The regions contributing the most to ice loss so far are Northwest and Southeastern Greenland.
• Study co-author Eric Rignot warns future ice loss could come from northern Greenland, which is seeing rapid changes. "We have time to prepare and re-adjust, but time is running out to avoid massive problems near the end of the century," he tells Axios.

What they're saying: Richard Alley, a glacier expert at Penn State University who was not involved in the new study, says the research is especially useful for laying out year-to-year variability in snowfall and mass loss.

"The big picture, from this work and much earlier work, remains clear: with warming, the increase in mass loss from surface melting has exceeded the increase in snowfall, causing net mass loss."

A "catastrophic" breeding failure has devastated the emperor penguin colony at Halley Bay in the Weddell Sea, Antarctica, with no chicks surviving during the past 3 years, scientists said Thursday, Rebecca Falconer and I report.

Why it matters: This particular emperor penguin colony was the world's second largest, with 15,000 to 24,000 breeding couples visiting the site annually.

• But the colony "has now all but disappeared," British Antarctic Survey researchers say in a statement accompanying the publication of their study in the journal Antarctic Science.
• Adult penguins have since fled the island, they say. Since the incident, scientists discovered the nearby Dawson Lambton colony has ballooned in size, indicating many of the adult emperor penguins have moved there.

What they did: The scientists used high resolution satellite data to track the penguin colony, including using markings from penguin guano that's visible from space (it tints brightly colored snow a brownish color) to estimate the colony size.

What they found: The researchers found repeat episodes of early sea-ice breakup in the area is the likely cause of the breeding failure.

• Sea ice broke up in October 2016, for example, "well before any emperor chicks would have fledged," the BAS states. This pattern occurred again in 2017 and 2018, the study finds.
• "What is important about this observation is that Halley Bay is a colony located far south in the Weddell Sea, in a location that we might expect to be a climate refuge for emperors, as the planet continues to warm," study co-author Phil Trathan tells Axios.
• "'Seeing events such as we describe is therefore important, as it means that even in areas previously thought safe, occasional events can have important consequences."

Why you'll hear about this again: Trathan tells Axios it's not clear whether the changes in sea-ice conditions at Halley Bay were specifically related to climate change. However, modeling based on climate change projections show significant declines in emperor penguin populations in Antarctica.

Everything's deadlier in the South (Bob Herman)

Pro Rata Podcast: Measles is back (Dan Primack)

NASA's InSight lander detects its first "Marsquake" (Miriam Kramer)

The science case for returning to the moon (Miriam Kramer)

The biggest nations' climate culpability (Ben Geman)

These Scientists Are Radically Changing How They Live To Cope With Climate Change (Zahra Hirji, Buzzfeed News)

How did crabs evolve 'crabbiness'? It's complicated (Michael Greshko, National Geographic)

The Unexpected Winners from Sea Star Wasting Disease (Larry Pynn, Hakai Magazine)

As patients tell apps they’re feeling suicidal, digital health startups scramble to respond (Rebecca Robbins, Stat News)

Sooner or Later Your Cousin’s DNA Is Going to Solve a Murder (Heather Murphy, New York Times)

Even at a microscopic level, blooming flowers are a sight to behold.

A new video shows a close-up look of baby flowers coming to life on the stem of a mustard plant, according to the National Institutes of Health director's blog.

• The red in the image outlines the green stem cells that are expressing the gene STM, which effectively keeps plant cells young until it’s time to reproduce, according to Collins.
• “As the video pans out, slightly older flowers come into view,” NIH director Francis Collins wrote. “These contain organs called sepals (red, bumpy outer regions) that will grow into leafy support structures for the flower’s petals.”

The video was made using photos taken by a microscope that were then turned into 3D images.