Coronaviruses are viruses that circulate among animals. Some coronaviruses can infect humans. Many human coronaviruses come from bats which are considered natural hosts of these viruses.
A pandemic is the rapid spread of a new human influenza around the world. Influenza pandemics happen when a new strain of a flu virus appears which can infect humans, to which most people have no immunity and which can transmit efficiently from human to human.
Swine influenza is a respiratory disease of pigs caused by type A influenza viruses that regularly cause outbreaks of influenza in pigs. Influenza viruses that commonly circulate in swine are called “swine influenza viruses” or “swine flu viruses.” Like human influenza viruses, there are different subtypes and strains of swine influenza viruses.
The Middle East respiratory syndrome coronavirus (MERS-CoV) is a new beta virus strain of an animal coronavirus that was first identified in Saudi Arabia in September 2012. This novel coronavirus differs from the previously identified coronaviruses such as the SARS coronavirus (SARS-CoV), which caused the 2003 SARS outbreaks.
Avian influenza is an infectious viral disease mainly found in birds, but under certain circumstances infections can also occur in humans even though the risk is generally very low.
Cholera is an acute diarrhoeal infection caused by the bacterium Vibrio cholera of serogroups O1 or O139. Humans are the only relevant reservoir, even though Vibrios can survive for a long time in coastal waters contaminated by human excreta.
Pertussis, also known as whooping cough, is a highly contagious acute respiratory infection, caused by the bacterium Bordetella pertussis. The disease is characterised by a severe cough, which can last two months or even longer.