ZAMBOANGA CITY: A lethal and contagious virus has killed shrimps and crabs in many fishponds in a village in Zamboanga City and even infected humans.
Local officials are investigating whether a mining company conducting exploration in the area may be dumping toxic chemicals into streams.
Government experts blamed white spot syndrome for the infection that is creeping in Vitali village and has affected fishpond owners, but local legislators called for more studies and tests after some villagers living near the river developed skin rashes.
But Atro Mining said it has not started operation in Vitali and denied allegations of pollution. It said it was still in the exploration stage of its iron ore project in Vitali and has not used chemicals.
According to the Journal of Virology of the American Society for Microbiology, White spot syndrome virus occurs worldwide and causes high mortality and considerable economic damage to the shrimp farming industry but no adequate treatments against this virus are available.
The Department of Agriculture, Fisheries and Forestry of Australia said the virus is known to occur in fresh, brackish and marine water and rapid mortalities have been reported in many countries of up to 80 percent or more within three to 10 days.
It said viral multiplication and disease appears to be induced by eye-stalk ablation, spawning, moulting and changes in salinity, temperature and pH and during plankton blooms.
It added that all life stages are potentially susceptible, from eggs to broodstock and that the virus transmission occurs from infected broodstock via cannibalism of sick or dying prawns, or directly through contaminated water. Birds can also transmit the disease from pond to pond by releasing caught prawns over neighboring ponds.