Yes, the pandemic state of emergency is over. But that doesn't mean that SARS-CoV-2 and other threatening viruses have vanished. Our viral coverage this year included a series on "Hidden Viruses" and a surprising theory about the workings of long COVID that was the most popular post of the year for Goats and Soda with over 1 million views. Here are our most read stories of the year with a viral theme.

Long COVID brain fog may originate in a surprising place, say scientists

Scientists studying the causes of long COVID symptoms are proposing a surprising pathway — through the gut. Their research weaves together several prominent lines of evidence on what might be driving the condition with its stubborn neurological symptoms such as brain fog, memory loss and fatigue. Published October 24, 2023.

Another Nipah outbreak in India: What do we know about this virus and how to stop it?

Nipah virus, known to spread from bats to human, has broken out in the state of Kerala. Here's what we know about the current cases and the ongoing efforts to quash this potentially fatal disease. Published September 15, 2023.

9 diseases that keep epidemiologists up at night

The World Health Organization keeps a list of viruses and bacteria with pandemic potential to guide scientists, governments and organizations as they invest energy and funds to study and stop the pathogens most likely to cause the greatest devastation to humans. We take a closer look at the 9 diseases on the current list. Published January 29, 2023.

How do pandemics begin? There's a new theory — and a new strategy to thwart them

Animals carry millions of pathogens, so it's a daunting task to find the one with the greatest potential to spark a pandemic. Now scientists are rethinking the way they hunt for that next new virus. One point is that viral "spillover" from animals to people may be much more common than thought. Published February 15, 2023.

A new flu is spilling over from cows to people in the U.S. How worried should we be?

Pigs and goats likely catch it too. It's been found in humans' noses in the American Southwest — and in the air at airports and at chicken farms in Malaysia. Published March 29, 2023.