Arboviruses causing human disease in the Australasian zoogeographic region

Abstract

Over 65 arboviruses have been reported from countries in the Australasian zoogeographic region, but only a few have been implicated in human disease. These include the flaviviruses Murray Valley encephalitis (MVE), Kunjin (KUN), Kokobera (KOK), and dengue, particularly types 1 and 2; the alphaviruses Ross River (RR), Barmah Forest (BF), and Sindbis (SIN); and the bunyaviruses, Gan Gan and Trubanaman. In this paper recent epidemiological and clinical results pertaining to these viruses are reviewed, with major emphasis on MVE and RR viruses. The extensive early studies of Australian arboviruses have been reviewed by Doherty [49, 50], and their ecology and vectors more recently by Kay and Standfast [87]. In addition, the biology of MVE and KUN [113] and RR [87, 114] viruses have been the subjects of more detailed reviews. The Australasian zoogeographic region is defined as countries east of the Wallace and Weber lines, two hypothetical lines in the Indo-Australian archipelago where the fauna of the Australasian and Oriental regions meet. Seroepidemiological studies of human arboviral infections have suggested that the Japanese encephalitis flavivirus and the chikungunya alphavirus occur only in the Oriental region, whereas the related MVE and RR viruses, respectively, are restricted to the Australasian region [85, 148]. Serological results from Wallacea, the zone between the Wallace and Weber lines, are not so clear-cut [85]. This review is therefore restricted to countries east of Wallacea, specifically New Guinea and Australia.

The Japanese Encephalitis Serological Group of Flaviviruses: a Brief Introduction to the Group

“…annulirostris mosquitoes (MARSHALL 1988). Indeed more than 90% of all MVE isolations have been made from this mosquito species (MACKENZIE et al 1994;RUSSELL 1995). Although serological studies have shown that various mammals can also be infected, they are not believed to playa significant role in natural transmission cycles.…”

“…The virus is believed to be enzootic in the north of Western Australia and the Northern Territory, and possibly in northern Queensland (SPENCER et al 2001). It is also enzootic in Papua New Guinea and parts of the eastern Indonesian archipelago (MACKENZIE et al 1994). Epidemics ofMVE occurred in south-eastern Australia in 1951 and 1974, with a few cases in 1956 and 1971, but all cases since 1974 have been from northern Australia (MARSHALL 1988;MACKENZIE et al 1993MACKENZIE et al , 1998CORDOVA et al 2000).…”

Dengue in Australia

“…The available evidence strongly suggests that dengue is not endemic in Australia, and that epidemics arise from virus introduced by viraemic travellers [24]. Imported cases of dengue in travellers are regularly diagnosed throughout Australia and dengue is the most commonly diagnosed flavivirus infection in the country.…”

Wolbachia enhances insect‐specific flavivirus infection in Aedes aegypti mosquitoes

“…Mosquitoes transmit a wide range of pathogens including viruses deemed arboviruses that cause widespread morbidity and mortality in humans and animals (Mackenzie, Gubler, & Petersen, 2004; Mackenzie et al., 1994). These viruses belong to diverse families including the Flaviviridae (genus: Flavivirus ) that are positive single‐stranded RNA viruses (Fauquet, Mayo, Maniloff, Desselberger, & Ball, 2005; Karabatsos, 1978).…”