Phil Savoie / Mosquito (Culex pipiens) carrier of the West Nile Virus close-up

Nigel Cattlin / Bird cherry-oat aphid (Rhopalosiphum padi) infestation on Wheat (Triticum aestivum) leaf with Barley yellow dwarf virus (BYDV) symptoms present.

Steve O. Taylor (GHF) / Straw-coloured fruit bats (Eidolon helvum), thought to be the natural reservoir of the Ebola virus, for sale in Brazzaville market, Republic of the Congo, 2013.

Mark Bowler / Yellow fever mosquito (Aedes aegypti) a mosquito that can spread dengue fever, chikungunya, and yellow fever viruses, and other diseases.

Pete Oxford / HIV signs awareness sign featuring Ao Naga headhunting tribesman in traditional festival clothing. Nagaland, North East India, October 2014.

Steve O. Taylor (GHF) / Warning notice for Ebola during the 2008 pandemic, northern Republic of the Congo (Congo-Brazzaville), 2008.

Adrian Davies / Bird flu poster telling people not to feed wild birds, Hong Kong, China, 2008

Karl Ammann / Ba'ka pygmy in Cameroon, West Africa being tested for Ebola virus after eating infected gorilla meat. Close genetic correlation between humans and apes means that many of the same viruses and parasite...

Nigel Cattlin / Aphid spread Sugar beet virus yellows through a field of infected Beet (Beta vulgaris), Cambridgeshire, UK.

Nigel Cattlin / Exterior skin of a potato (Solanum tuberosum) tuber showing spraing, a symptom of Tobacco rattle virus (TRV) and Potato mop-top virus (PMTV).

Nigel Cattlin / Cross section of a potato (Solanum tuberosum) tuber showing spraing, a symptom of Tobacco rattle virus (TRV) and Potato mop-top virus (PMTV).

Nigel Cattlin / Grapevine leaf roll virus symptoms on Pinot Noir grape leaves