The Department of Health's investigation into the case of suspected unregistered flu vaccines found 20 doses of suspected unregistered flu vaccines were supplied to a private medical practitioner in Yau Ma Tei in November.

This brings to four the total number of medical groups or clinics involved in the incident. 

All 20 doses of the suspected unregistered flu vaccines were used and the department is still tracing the supplier.

The doctor concerned had contacted the clients involved and none of them claimed they felt unwell after their vaccination.

Meanwhile, the department's hotline has received 642 calls from members of the public. Among these callers 353 said that they had approached medical centres which were involved in the incident for flu vaccination.

Eighteen of them claimed there was no severe adverse effect after injection but had minor reactions like low grade fever, redness and swelling at the injection site.