eBay is banning the sale of a number of items related to the novel coronavirus outbreak after rising prices raised concerns about price gouging.

The online auction giant says that "effective immediately" it will "block new listings and start to remove listings" that offer "masks including N95/N100 and surgical masks." Hand sanitizers and disinfecting wipes will also be banned.

eBay says these listings "may violate applicable US laws or regulations, eBay policies, and exhibit unfair pricing behavior for our buyers." Several states have anti-gouging laws prohibiting big price increases in a time of emergency.

In recent days, social media users have shared many screenshots of coronavirus-related items being offered at astronomical prices on eBay. One listing showed a package of 10 masks being sold for $200. Another showed a bottle of hand sanitizer being sold for $34.95—plus $8.70 for shipping.

Rival sites, including Amazon, have also struggled with sky-high prices for coronavirus-related items. So far, however, they haven't gone as far as banning the items outright.

Beyond concerns about price gouging, there's another problem with consumers stockpiling masks: it can lead to shortages for people who actually need them. Health care professionals need masks to avoid infecting patients during surgery and to prevent infected patients from infecting those around them. Some construction workers also need masks to protect themselves from fumes and dust.

At the same time, experts say that wearing a mask provides little benefit to a healthy person hoping to avoid infections. A mask can prevent an infected person from passing on a virus to others via coughs or sneezes. But experts say that wearing a mask doesn't do much to prevent viruses from being transmitted in the other direction.

"Seriously people- STOP BUYING MASKS!" tweeted US Surgeon General Jerome Adams late last month. "They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!"