Table 1.
Historical examples of spillover events [a] and species jumps [b]
| Virus (species name) | Animal hosts* | Date | Location | Reference* |
|---|---|---|---|---|
| [a] Spillover events | ||||
| Marburgvirus (Lake Victoria marburgvirus) | Unknown† | 1967 | Marburg and Frankfurt, Germany‡ | Martini, 1969; Towner et al., 2009 |
| Hantavirus (Sin Nombre virus) | Deer mouse | 1993 | Four Corners area, US | Centers for Disease Control, Prevention., 1993 |
| Monkeypox (Monkeypox virus) | Monkey, prairie dog, African rodents, et al. | 1970 | Liberia, Sierra Leone, Democratic Republic of Congo | Anon. 1971 |
| Human-adapted virus | Animal-derived virus | Animals with confirmed infections* | Date of first detected human outbreak/case | Location | Reference* |
|---|---|---|---|---|---|
| [b] Species jumps | |||||
| SARS coronavirus | SARS-like coronavirus | Civet, raccoon dog, bat§ | 2003 | Multicountry (Viet Nam, China, Singapore, Thailand, Canada) | Anon, 2003, Li et al., 2005; Guan et al., 2003 |
| HIV-1 | SIVcpz (simian immunodeficiency virus chimpanzee) | Chimpanzee | Before 1959¶ | Leopoldville, Belgian Congo (now Kinshasa, Democratic Rep of Congo) | Zhu et al., 1998; Korber et al., 2000; Worobey et al., 2008 |
| Influenza A subtype pdmH1N1 | Influenza A subtype H1N1 | Pig | 2009 | Northern Mexico | Anon, 2009 |
The distinction between spillover events and species jumps can be blurry. Spillover events are defined here as incidental human outbreaks without sustained human-human transmission; species jumps are driven by genetic changes that enable sustained human-human transmission. Viruses that have spilled over into human populations may subsequently evolve (i.e. jump) to efficiently transmit among human hosts.
Marburg viral RNA and antiviral serum antibodies were detected in Egyptian fruit bats (Rousettus aegyptiacus) in Uganda (Towner et al., 2009).
While these outbreaks occurred in Germany, both were caused by exposure to the same lot of green monkeys (Chlorocebus sp, formerly genus Cercopithecus) imported from Uganda.
While infected animals have been detected in markets, they have not yet been detected in the wild.
Two more recent studies have narrowed this estimate to 1915–1941 (Korber et al., 2000) and 1884–1923 (Worobey et al., 2008) using phylogenetic analyses.