Fill in the blank with a word chosen from the below in its proper form.pathogen pneumonia complication contagiousvaccine pandemic ultraviolet antiviral1. The 1918 influenza_______was the most severeonein recent history.2. Many people are wondering when we'll finally get to a coronavirus __________.3. Sunscreens play an important role in blocking _________ radiationfrom being absorbed by the skin.4. Most types of _________ cause fever, cough with sputum, shortness of breath and fatigue.5. By far, we know that coronavirus is a highly________ infection of the respiratory tract.6. If you get the flu this winter, you may be prescribed an__________medication.7. These serious _________ of COVID-19 are most likely to develop in elderly people, as well as those who have weakened immune systems.8. Infection with a____________does not necessarily lead to disease.