Arenaviruses are a type of small virus commonly found in rodents. When a person becomes infected with an arenavirus, symptoms usually begin within 10 days.
Varicella is caused by the varicella-zoster virus (VZV), which also causes shingles (herpes zoster). The virus typically affects children aged 2‒8 years.
Rotaviruses are the single most important cause of severe diarrhoeal illness in infants and young children worldwide. By the age of five years most children irrespective of socioeconomic setting will have been infected at least once. While infected, many children will be in need of medical attention due to extensive fluid loss.
Rubella is a mild febrile rash illness caused by rubella virus. It is transmitted from person to person via droplets (the virus is present in throat secretions). It affects mainly, but not only, children and when pregnant women are infected, it may result in malformation of the foetus. Humans are the only reservoir of infection.
Meningococcal disease is caused by Neisseria meningitidis, a bacterium with human carriers as the only reservoir. It is carried in the nose, where it can remain for long periods without producing symptoms.
Mumps is a viral infection first described by Hippocrates that in its classical form causes acute parotitis and, less frequently, orchitis, meningitis and pneumonia.