Egg prices are soaring in Japan as the current avian flu season sees a record 16 million birds marked for culling, impacting both the restaurant sector and households already struggling with inflation.

Egg-laying hens make up more than 90 percent of birds in the process of being culled, according to the agriculture ministry, limiting the supply of eggs and pushing prices higher.

File photo taken in November 2022 shows eggs sold at Akidai supermarket in Tokyo's Nerima district. (Kyodo)

The current bird flu outbreak has spread at an unprecedented pace since the season began in October, with at least 80 cases at poultry firms in 26 of the country's 47 prefectures.

As of March 2, the wholesale price per kilogram of medium sized eggs was 335 yen ($2.4) in Tokyo, the highest ever since 1993 when data first became available, according to JA.Z-Tamago Co., the egg seller within the JA agricultural cooperative group.

Concerns about shortages are also growing, with an increasing number of restaurants opting to suspend offering egg-based dishes.

It is expected to take at least six months until egg availability recovers to former levels.

Once an infection is confirmed at a poultry farm, all its birds are culled, after which the facility is sanitized and quarantine measures are put in place. It can take between three and seven months for such farms to return to raising chickens as normal again.

"Work to resume poultry farming is already under way and (production) should be active in early spring," a Ministry of Agriculture, Forestry and Fisheries official said.

"But it will take some time for numbers to recover because farms won't return to 100 percent capacity straight away," the official said.

Related coverage:

Japan Oct.-Dec. GDP growth cut to annualized 0.1% on slower consumption

Japan core consumer prices up 4.2% in Jan., fastest in over 41 yrs