About forty different arboviruses have been isolated from ticks associated with marine birds along all the coast of the world. The majority of these viruses belongs to 8 serogroups: Hughes, B, Kemerovo, Quaranfil, Nyamanini, Sakhalin, Unkuniemi and Upolu, while some others are non-grouped arboviruses. Two kinds of specialized ticks chiefly harbour these arboviruses: 1. The ticks of Ornitbodoros capensis complex from tropical, subtropical and temperate zones - 2. The ticks Ixodes uriae (= I. putus) and Ixodes signatus from subpolar, arctic and antarcitc zones and the surrounding temperate areas. All these ticks may attack humans, and severe pruritus and/or undifferenciated febrile illness may result. From a pathological point of view, some of these arboviruses, i.e. Soldado, Aride, Saumarez Reef, act as pathogens for marine birds inducing nest desertion and death or abnormal development of newly batched chicks. On the other hand, antibodies against other viruses, with well known or suspected epidemic potency, such as West Nile, Tyuleniy, Okhotskiy viruses, are currently found in human beings in certain coastal areas. These epidemiological data deserve further attention from concerned Health autorities.