Read Hugh Pennington's analysis of the diseases we should really be worrying about

E.coli O104:H4

A toxic new strain of the Escherichia coli bacterium. An outbreak in Germany in May 2011 infected over 4,000 people and killed 50. Primarily food-borne, the bacteria causes haemolytic uremic syndrome, which destroys red blood cells and causes vomiting and diarrhoea, at far greater rates than other strains of E.coli.

West Nile virus

Part of the same family of viruses as yellow fever and dengue, West Nile virus can cause meningitis as well as damage to the brain and spinal cord. Only 1 in 100 cases are serious but it tends to be more severe in the elderly. Previously seen sporadically in Africa and the Middle East, an outbreak occurred in New York in August 1999. It has since spread throughout North America.

Chikungunya

The most common symptoms of the chikungunya virus, transmitted by mosquitoes, are fever and joint pain. Symptoms may also include headache, muscle pain, joint swelling, or rash. Outbreaks have occurred in Africa, Asia and the Indian and Pacific Oceans. In late 2013, chikungunya was found for the first time in the Americas, on islands in the Caribbean. In 2014, 758 cases have been reported in the United States. There is currently no vaccine or effective medical treatment.

Syphilis

Syphilis is a bacterial infection that is usually transmitted sexually. Between 2003 and 2012, diagnoses of infectious syphilis at clinics in England increased by 61 per cent in men, and diagnosis rates are now at their highest since the 1950s. Syphilis symptoms can take years to manifest themselves. Influenza In 1918-19, a global flu pandemic killed around 40m people. Pandemics occur when new influenza viruses emerge. By March 2010, nearly a year after the emergence of the swine flu virus, it had claimed 457 lives.