When is a rat not a rat? When it's a mouse, except in China and Japan where the word for rat and mouse is identical. Laoshu in Chinese and nezumi in Japanese are all-purpose words for the little furry creature known to scurry about kitchens and granaries since time immemorial.

Rat is the first animal in the Chinese zodiac, by dint not of size or power but resourcefulness, hitching a legendary ride on an ox to win a race against 12 awesome contenders. It's got a generally positive image, as a symbol of fertility, and even its negative connotations of cunning, stealth and self-preservation have a positive side.

In the West, the linguistic split into mouse and rat has tended to cast the smaller of the two in more favorable light. Rats are the first off a sinking ship, but a cheery, chirpy mouse is the titular mascot of Disneyland. Rats are associated with filth and infestation, but mice are cute and kept as pets. (Actually, rats make nice pets, too, but they've got an image problem.)

Ahead of Spring Festival this year, the pneumonia outbreak in Wuhan, Hubei province, has cast a shadow over the holiday mood nationwide. And health experts indicate the new strain of coronavirus may come from wild animals, for instance, bamboo rats. This may tarnish "rats' image" as the black death still haunts people's minds.

Nowhere is the image of rats darker than in the dark ages. They are blamed for the Black Death. But is this historically accurate? National Geographic telecast a program in 2018 suggesting that fleas and lice, not rats, were a more likely vector of the epidemic, at least according to computer models.
Even today, a random search of "rats versus mice" on Google brings up a long list of exterminators and pest control technique. A search on Baidu, in contrast, brings up mostly cultural references, explaining how the two differ in appearance, in keeping with English language usage.

As if association with the plague for centuries isn't enough, the outspoken US leader has revived the use of rat in political attacks, castigating Baltimore, a city in Maryland, the district of African-American Elijah Cummings, as a "disgusting, rat and rodent infested mess".

And there has been a disturbing upswing intolerant political talk, from the separatist agitators to reactionary politicians, denigrating certain groups by using words with troubled history such as "rat-infested" and "vermin."

Last year a cartoon in the United Kingdom-based Daily Mail depicted gun-carrying Muslim "terrorists and rats" sneaking across a border, immediately provoking controversy.

Rats get a bad rap. Even as portrayed by a ballet dancer, a Rat King is a scary thing, as children know from watching Tchaikovsky's Nutcracker. The villainous ruler battling a righteous prince was called "Mausekonig" or "Mouse King" in the German original.

To the English speaker's ear, of course, Mouse King sounds nicer.

Consider E.B. White's Stuart Little, the 1945 story about a privileged white mouse adopted into a loving family in Manhattan, New York. Variations of "town mouse and country mouse" pop up all across Europe, and not surprisingly, the popular pairing goes all the way back to Aesop, who also famously wrote The Lion and the Mouse.

There are courtly mice, such as Reepicheep the courteous, a swashbuckling talking mouse in The Chronicles of Narnia series by C.S. Lewis, and there's the tidy Mrs Tittlemouse, a clean, cuddly creation of Beatrix Potter. And the March sisters in Louisa May Alcott's Little Women have a pet mouse named Scrabble.

Needless to say, Hollywood is in on the game. There's American Tail, a pun-packed parable about Mousekewitzes, a Russian-Jewish family of mice who seek a new life on shores of the United States, and there's animation film Ratatoille which features Remy, an idealistic rat (a rat!) who wants to be a chef.

Geronimo Stilton is a children's books character with a cheesy surname. John Steinbeck's Of Mice and Men is entirely about men, not mice, but the title was inspired by a Robert Burn's poem, To a Mouse, which speaks to the folly of creatures that scheme.

Flowers for Algernon by Daniel Keyes is a dark 1959 tale in which the death of an experimental mouse presages the demise of the human drug-trial patient. Mrs. Frisby and the Rats of NIMH, a trilogy by Robert O'Brien and later his daughter Jane Leslie Conly, explores the world of experimental animals that gain intelligence.

When the space race got underway, all kinds of animals were put on top of rockets to see how they would fare in space; most of them never returned. In 1972, NASA sent mice along on the final Apollo mission. Named Fe, Fi, Fo, Fum and Phooey, they completed a staggering 75 orbits of the moon. All but one of the mice made it back to the home planet safely, after which the rest were promptly dissected.

Male rats are "bucks", female rats "does", pregnant rats "dams" and the offspring "pups".

The mouse/rat has long been a companion of human habitation, so much so that it is considered a commensal species, living more or less in harmony with humans. That's not to say they don't cause trouble. A clue to rat nature can be found in the traditional terminology.

A group of rats is called "a mischief".

The author is a media researcher covering Asian issues.

The views don't necessarily represent those of China Daily.