(Replaces earlier version that contained factual errors)Canadian health officials are continuing investigations into a type of swine flu vaccine that has been linked to possible allergic reactions. But they stress the number of adverse reactions from the batch concerned is only slightly higher than normal. GlaxoSmithKline alerted Canadian authorities to a batch of the vaccine feared to have potential side effects. Dr. Joel Kettner, the Chief Medical Officer of Manitoba, said: “We’ve been asked by the manufacturer GSK not to use this vaccine at this time pending further investigation.” Of the millions of doses administered in Canada so far, a small number of adverse reactions have been reported. Dr. Neil Rau, an infectious disease specialist said: “It is a serious thing that has the potential to kill – but fortunately seems to be relatively rare.” The recall affects 172,000 doses. But health officials have said there is no cause for alarm. Canada has been particularly badly hit by the H1N1 flu virus.