KHV Outbreak Affecting Pelian Fish, Government Takes Firm Action

6 April 2026

KOTA KINABALU: The State Government is taking firm and comprehensive action to address the outbreak of pelian fish deaths confirmed to be caused by Koi Herpesvirus (KHV), following incidents reported since 1 August 2025.

Minister of Agriculture, Fisheries and Food Industry, Datuk Jamawi Jaafar, said the large-scale fish deaths have affected several major rivers in the districts of Keningau, Tambunan, Tenom, Penampang, Tuaran, Ranau and Sipitang.

He said laboratory analysis conducted by the Biosecurity Laboratory of the Sabah Fisheries Department at the Likas Fisheries Complex confirmed KHV as the primary cause of the incident.

According to him, KHV is a dangerous pathogenic virus that infects fish from the Cyprinidae family and is classified as a high-impact aquaculture disease with a very high mortality rate.

“Scientific data indicate that mortality rates can reach between 80 and 100 per cent in infected populations. The virus is active in water temperatures of around 18 to 28 degrees Celsius and becomes more aggressive when there are sudden temperature fluctuations.

“It is also capable of remaining latent before reactivating under environmental stress such as drought conditions, and can spread through water, direct contact, contaminated equipment and the transfer of live fish,” he said in a statement today in response to issues circulating on social media regarding the pelian fish deaths, while providing an official explanation of the actual cause and the control measures being implemented by the State Government.

Jamawi said field investigations found that the main cause of the outbreak was the release of non-native fish, particularly koi and other species from the Cyprinidae family not endemic to Sabah, into public waters without control.

He said such irresponsible actions violate biosecurity principles and have led to serious infections among local species, including the pelian fish.

He added that the current dry season has also increased water temperatures, creating conditions conducive to viral activation and heightening the risk of further mass fish deaths in the near term.

In response, he announced several firm measures, including instructing the Sabah Fisheries Department to issue a special circular to all districts for the immediate implementation of control actions.

“All Tagal Committee Chairmen are instructed to identify, capture and remove all koi fish and non-endemic Cyprinidae species from tagal areas and rivers."

“These fish must be destroyed immediately in accordance with the prescribed biosecurity disposal standard operating procedures (SOPs), and any release is strictly prohibited,” he said.

Meanwhile, Jamawi said the ministry has also imposed a temporary ban on all import and export activities involving fish from the Cyprinidae family into and out of Sabah.

He said the ban covers live fish, fry, broodstock and any form of biological transfer that poses a risk of spreading the KHV virus, and takes immediate effect until a biosecurity risk assessment is completed.

He also stressed that enforcement under the Sabah Inland Fisheries Enactment will be strengthened without compromise.

“Any party found releasing non-native fish into public waters, failing to comply with destruction orders or violating the import and export ban will face strict legal action,” he said.

Jamawi also issued a stern warning to aquaculture operators, ornamental fish breeders and the public not to introduce or release non-native fish species into public waters and to fully comply with all biosecurity requirements.

He said all parties must also extend full cooperation to the authorities in efforts to curb the spread of the outbreak.

“This incident poses a serious threat to Sabah’s inland aquatic biodiversity and could result in the permanent loss of endemic fish species such as the pelian if not addressed in an aggressive and integrated manner.

“There will be no compromise on biosecurity threats, firm action will be taken without exception,” he said.