LONDON (AP) — GlaxoSmithKline says one of its swine flu vaccines has been certified by the World Health Organization, making it available for donors to buy for developing countries. In a statement issued Tuesday, GlaxoSmithKline PLC said WHO had approved its Canadian vaccine after examining its quality and safety data. The vaccine contains an adjuvant, a chemical compound to boost the immune system. Last month, Glaxo advised health authorities not to use one batch of its Canadian-manufactured swine flu vaccine in case it triggered life-threatening side effects like anaphylactic shock. Several vaccine makers have promised WHO 156 million doses of swine flu vaccine, which it hopes to start shipping to 95 poor countries this month.