Influenza, also known as "the flu”, is an infectious disease caused by a highly contagious respiratory virus, influenza virus. It is most common during the fall and winter months. Generally, there are four different types of influenza viruses: influenza A, B, C, and D.
Respiratory syncytial virus (RSV) causes infections of the lungs and respiratory tract. It's so common that most children have been infected with the virus by age 2. Respiratory syncytial (sin-SISH-ul) virus can also infect adults.
In adults and older, healthy children,
RSV symptoms are mild and typically mimic the common cold. Self-care measures are usually all that's needed to relieve any discomfort.
Influenza – or flu – is a respiratory illness that is caused by influenza viruses. Influenza viruses type A and type B cause seasonal epidemics in human beings on an annual basis. Furthermore, influenza A is also responsible for the pandemics that periodically appear, the most recent one being that which was caused by a H1N1 strain in 2009.
The illnesses range from mild to severe. According to WHO, the annual epidemics result in several million cases of severe illnesses and approximately 250,000 to 500,000 deaths per year worldwide. Severe cases and deaths mostly occur among the people in high-risk groups, e.g. young children, pregnant women, people aged over 65 years and those who suffer from certain medical conditions.
Respiratory Syncytal Virus (RSV)