According to American Shipper:
Chinese authorities have said that containers from certain countries shall be subject to effective anti-mosquito treatment in order to prevent the virus from spreading, which has left many shippers concerned.
U.S. shippers are expressing concern and confusion about a Chinese regulation calling for treatment of containers or fumigation in order to prevent the spread of the Zika virus. Ocean carrier Mediterranean Shipping Co. (MSC) issued a trade advisory to customers Wednesday noting that Chinese authorities have said, “In order to prevent the spread of the Zika virus, containers from all the involved countries shall be subject to effective anti-mosquito treatment." MSC's notice continued, “With immediate effect, it means that there is a need to provide a certificate of extermination of mosquito. If no certificate is provided, the buyer must fumigate the cargo at arrival at the port of destination.”
Source: American Shipper