China issued new rules on Wednesday to tighten notification of cases of African swine fever (ASF), including possible incentives for whistleblowers, amid concerns that outbreaks of the highly contagious disease are being under-reported, according to a Reuters report.

China is currently struggling to contain ASF, with more than 60 outbreaks in 18 provinces since early August, leading to the culling of hundreds of thousands of pigs, Reuters said.

Under the new rules from the agriculture ministry, it is forbidden to delay or obstruct the reporting of new outbreaks, to issue false test reports or illegal health certificates and to illegally dispose of infected animals, the report said.

Many experts suspect that the number of outbreaks in China is much higher than reported, given the fragmented nature of the country’s farming sector.

“I think the reporting is not complete,” Qin Yinglin, chairman at major pig farming firm Muyuan Foods Co. Ltd., told Reuters at a conference last month.

“The sites that have reported outbreaks are not in succession. They just abruptly emerge,” he said.

China has already banned the transport of live hogs from infected provinces and neighboring regions to prevent the spread of ASF and requires trucks carrying live animals to be registered and to use location-tracking systems.

China has also banned the practice of feeding food scraps and swill to swine.

However, the rules have been flouted, with some cases reported of illegal sales and transportation of pigs, Reuters reported.