After government data showed egg prices in December were up 138 percent from a year before, at $4.25 per dozen, some analysts say it could be four to six months before prices ebb

The primary driver has been a devastating outbreak of avian influenza, also called A-I or bird flu.

"One of the worst AI (Avian Influenza, 'Bird Flu') outbreaks that we've ever seen in this country. We've lost right around 43 million egg laying hens."

The disease forced farmers to cull millions of egg-laying hens, decimating supplies, which are now being rebuilt.

Other price drivers are the cost of feed grain, fuel and labor, all boosted by inflation.

If both those input costs and the bird flu abates, prices could follow, says Brian Moscogiuri a global trade strategist egg supplier Eggs Unlimited in Irvine, California.

"The hope is that, you know, as we get into the summer months, we will see, you know, repopulation kind of fully get us back to the levels that, you know, we need to be to balance supply and demand. But there is a lot of uncertainty regarding, again, the spring migration and birds moving back up north and flying over the country and the amount of AI that they've been finding in the wild bird population. But I would say hopefully the consumers have already seen the highest price that they will see at the shelf and we'll potentially see some relief in the future, near future."

The surge in egg prices has led one U.S. farm group to demand a federal probe.

The group Farm Action last week sent a letter to the chair of the Federal Trade Commission asking her to investigate record-high profits at the top U.S. egg company, Cal-Maine Foods.

An attorney for Farm Action said he wanted the FTC to look into whether "consumers are being price-gouged."

The FTC declined to comment.

Cal-Maine, which controls 20% of the retail egg market, reported last month that its most recent quarter saw a 110 percent rise in net sales compared with a year earlier. Gross profits jumped more than 600% over the same period.

In a statement, Cal-Maine said that higher production costs, along with avian flu, were contributing to higher prices.

The CEO boasted in the firm's latest quarterly report about the company's record sales, which it attributed to high prices, avian flu, and strong consumer demand.