direct physical contact: shaking hands, chicken-pox, air bourne: cough, sneeze, measles, covid 19, indirect physical contact: hepatitis, water borne: cholera, typhoid, food borne: undercooked meat, e.coli, salmonella, vector borne: mosquito, malaria,

transmission of pathogens

排行榜

視覺風格

選項

切換範本

恢復自動保存: ?