The Respiratory Syncytial Virus (RSV) is a globally distributed respiratory pathogen. In the winter season it causes epidemic respiratory infections in all age groups. Among healthy adults, RSV infections are generally mild with common cold-like symptoms. However, primary RSV infections among infants can take a severe course. In fact, RSV is the most frequent cause of lower respiratory tract infections among infants and it causes significant morbidity and mortality in this age group. The course and outcome of primary RSV infection are highly variable. While some children have only mild symptoms such as during a common cold, others are severely ill and need hospitalization. Pre-term birth is one important known risk factor for severe RSV infection. However, most cases of a severe primary RSV infection occur among infants that do not have any known risk factors. Globally the most severe cases are responsible for more than 3 million hospital admissions and 59.600 in hospital deaths every year.
To the pictures: Figure 1 shows uninfected cells (purple nuclei). Figures 2, 3 and 4 show progressive RSV infection; the cells were infected with a virus (green) and a viral protein was stained (orange/red); in the superposition of both colours they appear yellow; as the infection progresses neighbouring cells fuse. Source: Svenja Sake/Twincore