<p dir="ltr">Outbreaks of viral infections caused by idiopathic or re-emerging viruses pose a threat to human health, and in particular to the elderly. This is usually attributed to the modifications in the genome of the viruses. Many social, economic, and environmental factors are associated with the increase in incidences of outbreaks. These include poverty, overpopulation, malnourishment, globalisation, migration for work opportunities, unplanned urbanisation, deforestation, an increase in diseases affecting the immune system, as well as alterations in farming practices.</p>