What are the fundamental biological characteristics of influenza viruses that make them prone to causing epidemics and pandemics?

Influenza (flu) is a very contagious viral infection that affects the air passages of the lungs. It causes a high fever, body aches, a cough, and other ... Flu viruses seem to spread most predominantly through aerosol infection where people become infected because of droplets in the air that contain the virus. The ... Symptoms of the common cold caused by the rhinovirus include sore throat, runny nose, coughing, sneezing, watery eyes, headaches, and body aches. Jun 22, 2024 ... Summary. Some sexually transmitted infections can cause flu-like symptoms such as fever, sore throat, and swollen lymph nodes. These include ... Influenza virus infections cause between 291 243 and 645 832 deaths annually, with the highest burden in low-income settings. Research in high-income ... Signs & Symptoms of the Flu · Fever or feeling feverish/chills · Cough · Sore throat · Sneezing · Runny or stuffy nose · Muscle or body aches · Headache ... Feb 10, 2025 ... What causes body aches? ... Viral infections, such as the flu, COVID-19 or common cold, and some bacterial infections can cause widespread body ... Oct 18, 2018 ... What is keto flu? The so-called keto flu is a group of symptoms that may appear two to seven days after starting a ketogenic diet. · What causes ... Viral gastroenteritis is not harmful. However, viral gastroenteritis can become dangerous if it leads to dehydration. Aug 13, 2024 ... Flu is a contagious respiratory illness caused by influenza viruses · Flu can cause mild to severe illness · Most experts believe that flu viruses ...