Why did the Great Flu spread so easily at the beginning of the pandemic?

Influenza, or flu, is a virus that attacks the respiratory system. The flu virus is highly contagious: When an infected person coughs, sneezes or talks, respiratory droplets are generated and transmitted into the air, and can then can be inhaled by anyone nearby

economic impact of malaria is estimated to cost africa $12 billion every year. this figure factors in costs of health care, absenteeism, days lost in education, decreased productivity due to brain damage from cerebral malaria, and loss of investment and tourism.