Our Expert Voices conversation on emerging diseases.

New technologies allow us to observe cross-species transmission in ways we could not before, but we lack the fundamental understanding of the relationship between virus genetics and transmission in humans to distinguish the next Ebola or HIV from viruses that pose no threat.

Influenza viruses are a microcosm of this process. There are thousands of confirmed instances of humans being infected, sometimes fatally, with non-human flu strains; but only a handful of strains have adapted to cause human epidemics. However, those that do adapt can be devastating, as was the 'Great Influenza' of 1918, which killed 20-100 million people in only a few years. The 1918 flu pandemic and others were likely preceded by multiple instances of animal-to-human transmission of related viruses.

Bottom line: We are the first generation with the tools to observe this pre-pandemic 'viral chatter' between species, but we will be unable to develop any sort of pandemic early warning system until we better understand how the genetics of viruses relate to their ability to transmit in humans. Doing this for influenza could establish the fundamental biological theory needed to identify, and perhaps stop the next HIV or Ebola before it happens.

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Updated 27 mins ago - Politics & Policy

Voters in Wisconsin, Michigan urged to return absentee ballots to drop boxes

Signs for Joe Biden are seen outside a home in Coon Valle, Wisconsin, on Oct. 3. Photo by KEREM YUCEL via Getty

Wisconsin Democrats and the Democratic attorney general of Michigan are urging voters to return absentee ballots to election clerks’ offices or drop boxes, warning that the USPS may not be able to deliver ballots by the Election Day deadline.

Driving the news: The Supreme Court rejected an effort by Wisconsin Democrats and civil rights groups to extend the state's deadline for counting absentee ballots to six days after Election Day, as long as they were postmarked by Nov. 3. In Michigan, absentee ballots must also be received by 8 p.m. on Election Day in order to be counted.

35 mins ago - Technology

Facebook warns of "perception hacks" undermining trust in democracy

Photo Illustration: Sarah Grillo/Axios. Photo by Jamie Squire/Getty Images

Facebook warned Tuesday that bad actors are increasingly taking to social media to create the false perception that they’ve pulled off major hacks of electoral systems or have otherwise seriously disrupted elections.

Why it matters: "Perception hacking," as Facebook calls it, can have dire consequences on people's faith in democracy, sowing distrust, division and confusion among the voters it targets.

Obama: Trump is "jealous of COVID's media coverage"

Former President Barack Obama launched a blistering attack on President Trump while campaigning for Joe Biden in Orlando on Tuesday, criticizing Trump for complaining about the pandemic as cases soar and joking that he's "jealous of COVID's media coverage."

Driving the news: Trump has baselessly accused the news media of only focusing on covering the coronavirus pandemic — which has killed over 226,000 Americans so far and is surging across the country once again — as a way to deter people from voting on Election Day and distract from other issues.