BEIJING - A surge in African swine fever infections in China is set to reduce hog output later in 2023, farm managers and analysts said this week.

It will push up prices in the world’s top pork consumer as demand recovers.

The incurable disease has plagued China for years.

An initial wave during 2018 and 2019 killed millions of pigs and led to a dramatic decline in meat output that roiled global markets.

Chinese farms have significantly improved hygiene and procedures since then to reduce the impact of the virus.

However, it still circulates constantly, often spiking in winter.

Infections in 2023 began to surge relatively late in the season, around the Chinese New Year holiday in January, when millions of people travelled after China had relaxed its Covid-19 curbs, said three managers at pig farming companies and analysts.

“Data from swine fever virus testing companies show that the number of positive detections exploded after the new year holiday. The order of magnitude in a single month has reached the level of the whole year of 2022,” said analysts at Huachuang Securities in a March 13 report.

“We guess that the current swine fever infection area in northern production areas may be reaching 50 per cent,” it added.

Northern provinces such as Shandong and Hebei are among the top producers of hogs.

A senior manager at one of the country’s top hog producers agreed with the estimate.

“We do see quite many new infections in March. We feel it hasn’t ended yet, that’s the problem,” he said, declining to be identified due to the sensitivity of disease outbreaks in China.

Chinese farms typically do not report disease outbreaks to the government.

The Ministry of Agriculture and Rural Affairs did not immediately respond to a request for comment.

The impact of the outbreaks depends on how early they are detected and how they are managed, said the pig company manager.

A milder form of the virus that has few clinical symptoms is common, making it challenging to detect, he added.

Chinese hog prices have hovered around 15 yuan (S$2.90) per kilo since late 2022, pressured by weak demand and excess supply.

Large losses in 2022 encouraged many farmers to downsize herds in the winter, which has pushed up slaughter volumes.

Infected pigs sent to slaughter could also be weighing on the price, said Mr Jim Long, chief executive of Canadian genetics company Genesus, which sells breeding pigs in China.

“We continue to believe the low China hog price is due to many pigs going to slaughter at any weight due to ASF (African swine fever) breaks,” he wrote in a report this week.

The disease outbreaks, as well as the prior herd reductions, will lead to fewer hogs reaching the market when demand improves in the second half of 2023, said the Huachuang report. REUTERS