Eggs are disappearing from store shelves due to shortages caused by the avian flu outbreak, but never fear — the eggs used to ...

疫苗接种在降低病原体感染导致的重症率和死亡率方面取得了不可否认的成功。然而，疫苗接种部位与病原体暴露途径（如呼吸道病原体）之间的脱节意味着许多疫苗仍难以有效预防初始感染。这在已有疫苗中表现得很明显，如无细胞百日咳疫苗不能很好阻止病原体在鼻腔定植，而最 ...