Pilchard herpesvirus detected in dead sardines along South Africa's West Coast, further investigation underway
Pilchard herpesvirus PHV, a virus previously unrecorded in South African sardines, has been identified in fish linked to recent mass mortalities along the West Coast. The Department of Forestry, Fisheries and the Environment DFFE confirmed the presence of PHV genetic material in dead sardines and, at lower levels, in some apparently healthy fish. However, the DFFE stated that the virus alone might not be sufficient to explain the mass deaths, prompting scientists to investigate potential environmental stressors such as harmful algae, low oxygen, or unusual oceanographic conditions. Tests for paralytic toxins from harmful algal blooms in areas like Saldanha Bay yielded no detection, and while low levels of domoic acid and yessotoxin were found, they were highest in healthy samples, suggesting these toxins were unlikely to be the primary cause. A task team involving the DFFE, the fishing industry, and other stakeholders will be established to formulate a coordinated response plan. Disease surveillance is being expanded across the West, South, and East coasts. PHV has been associated with sardine mortality events in Australasia in the 1990s but was also found in healthy populations without continuous mortality. The DFFE emphasized that the detection of PHV does not indicate that commercially caught healthy sardines or canned products are unsafe, and a general suspension of fishing or canning is not currently justified. The public is advised not to collect or consume dead or dyin