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Identification of Zika virus vectors and implications for control
Const?ncia F J Ayresemail
Published Online: 04 February 2016
Article has an altmetric score of 79
DOI: http://dx.doi.org/10.1016/S1473-3099(16)00073-6
showArticle Info
Summary
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Surprisingly, previous studies that have investigated the vector competence for Zika virus have neglected other mosquito species,7, 8, 9 such as Culex species, which are very abundant in the tropical areas where Zika virus has spread and have also transmitted arboviruses that are closely related to Zika virus, such as West Nile virus. Faye and colleagues10 reported a long list of mosquito species from which Zika virus strains were isolated, including several species of Aedes and Anopheles coustani. Diallo and colleagues11 surveyed mosquitoes from different environments from Senegal and detected by RT-PCR the presence of Zika virus in ten species from the genus Aedes, and Mansonia uniformis, Anopheles coustani, and Culex perfuscus. These mosquito species probably contribute to the zoonotic cycle of Zika virus transmission. However, the simple detection of a virus in a mosquito sample does not incriminate it as a vector. It is important to prove in laboratory conditions that an organism is able to acquire the pathogen and maintain and transmit it to other hosts. Additionally, even if the ability of a given species to transmit a pathogen is proven in laboratory conditions, that species is not necessarily the primary vector. A good example involves Aedes aegypti and Aedes albopictus in Brazil. Both species are known as good dengue vectors; however, A aegypti plays a major part in dengue transmission in the country due to its vectorial capacity, whereas A albopictus does not because its level of infestation is low and it prefers sylvatic environments.
In this respect, the urban transmission of Zika virus could involve other mosquito species, especially considering the adaptability of this virus,12 and this issue deserves urgent attention. Vector control strategies must be directed at all potential vectors. To assume that the main vector is A aegypti in areas in which other mosquito species coexist is naive, and could be catastrophic if other species are found to have important roles in Zika virus transmission. Therefore, researchers from different institutions who are working on vector?pathogen interactions must attempt to answer this important question as soon as possible, to direct control actions towards the correct target and to help to minimise the drastic effects of Zika virus disease outbreaks.
...
http://thelancet.com/journals/laninf/article/PIIS1473-3099(16)00073-6/fulltext
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Zika, a Mosquito-Transmitted Virus1
L. P. Lounibos, B. W. Alto, N. D. Burkett-Cadena, C. C. Lord, C. T. Smartt, C. R. Connelly, and J. R. Rey2
...
Mosquito Vectors of Zika Virus
Forest-dwelling species of the genus Aedes, especially Aedes africanus in Uganda (Haddow et al. 1964), and Aedes furcifer, Aedes luteocephalus, and Aedes africanus in Senegal (Diallo et al. 2014), maintain the African Zika cycle between mosquitoes and arboreal primates. Males of Aedes furcifer caught infected in the wild provide evidence that Zika can be transmitted from an infected female vector to her offspring through the egg stage (Diallo et al. 2014).
Serological investigations showed that human infections with Zika can be common. For example, 40% of an urban population in Nigeria had antibodies to the virus (Fagbami 1979). During spillovers from the forest cycle into domestic or cleared habitats, other Aedes species have been found infected with Zika, such as Aedes metallicus and Aedes vittatus in SE Senegal (Diallo et al. 2014). The epidemiological importance of Zika isolations in Senegal from mosquitoes of other genera, notably species of Mansonia, Culex, and Anopheles, remains unclear (Diallo et al. 2014).
In the invasive range of the virus outside of Africa, the most likely vector of Zika is Aedes aegypti, first recognized as infected in nature in Malaysia (Marchette et al.1969). The preference of domestic Aedes aegypti for feeding on human hosts in tropical cities overrides its inefficiency in developing the ZIKV (Diagne et al. 2015). Aedes albopictus has been implicated as a Zika vector in Gabon (Grard et al. 2014) and has expanded its invasive range worldwide. This finding assumes greater importance because both the mosquito and Zika virus are extending their range and thus it is possible that human-feeding populations of this vector species may co-occur with the emergent virus. In Micronesia, the endemic Aedes hensilli was the probable vector of Zika during the 2007 epidemic of the disease on Yap Island (Duffy et al. 2009).
Which mosquito species native to the Americas might become vectors of Zika remains to be determined by future research. Concern is justified that Zika could become endemic in tropical New World forests, in transmission cycles between arboreal treehole mosquitoes, such as species of Haemagogus and Sabethes, and Neotropical non-human primates, just as occurred in South and Central America for yellow fever virus centuries earlier after its introduction and spread from Africa (Barrett and Higgs 2007). The relative importance of different vector species in the current epidemics in the Americas is unknown, but Aedes aegypti and Aedes albopictus are the most probable transmitters. If confirmed, their capacity to transmit the virus would increase concern in other areas where these species are present.
...
http://edis.ifas.ufl.edu/in1120
--------------------------------------------------------------------------------------------------------------------------
See also:
Canadian mosquito spread of Zika untested
https://flutrackers.com/forum/forum...092-canadian-mosquito-spread-of-zika-untested
Brazilian experts investigate if 'common mosquito' (Culex) is transmitting zika virus
https://flutrackers.com/forum/forum...mon-mosquito-culex-is-transmitting-zika-virus
Const?ncia F J Ayresemail
Published Online: 04 February 2016
Article has an altmetric score of 79
DOI: http://dx.doi.org/10.1016/S1473-3099(16)00073-6
showArticle Info
Summary
Full Text
References
...
Surprisingly, previous studies that have investigated the vector competence for Zika virus have neglected other mosquito species,7, 8, 9 such as Culex species, which are very abundant in the tropical areas where Zika virus has spread and have also transmitted arboviruses that are closely related to Zika virus, such as West Nile virus. Faye and colleagues10 reported a long list of mosquito species from which Zika virus strains were isolated, including several species of Aedes and Anopheles coustani. Diallo and colleagues11 surveyed mosquitoes from different environments from Senegal and detected by RT-PCR the presence of Zika virus in ten species from the genus Aedes, and Mansonia uniformis, Anopheles coustani, and Culex perfuscus. These mosquito species probably contribute to the zoonotic cycle of Zika virus transmission. However, the simple detection of a virus in a mosquito sample does not incriminate it as a vector. It is important to prove in laboratory conditions that an organism is able to acquire the pathogen and maintain and transmit it to other hosts. Additionally, even if the ability of a given species to transmit a pathogen is proven in laboratory conditions, that species is not necessarily the primary vector. A good example involves Aedes aegypti and Aedes albopictus in Brazil. Both species are known as good dengue vectors; however, A aegypti plays a major part in dengue transmission in the country due to its vectorial capacity, whereas A albopictus does not because its level of infestation is low and it prefers sylvatic environments.
In this respect, the urban transmission of Zika virus could involve other mosquito species, especially considering the adaptability of this virus,12 and this issue deserves urgent attention. Vector control strategies must be directed at all potential vectors. To assume that the main vector is A aegypti in areas in which other mosquito species coexist is naive, and could be catastrophic if other species are found to have important roles in Zika virus transmission. Therefore, researchers from different institutions who are working on vector?pathogen interactions must attempt to answer this important question as soon as possible, to direct control actions towards the correct target and to help to minimise the drastic effects of Zika virus disease outbreaks.
...
http://thelancet.com/journals/laninf/article/PIIS1473-3099(16)00073-6/fulltext
------------------------------------------------------------------------------------------------------------------------------------------
Zika, a Mosquito-Transmitted Virus1
L. P. Lounibos, B. W. Alto, N. D. Burkett-Cadena, C. C. Lord, C. T. Smartt, C. R. Connelly, and J. R. Rey2
...
Mosquito Vectors of Zika Virus
Forest-dwelling species of the genus Aedes, especially Aedes africanus in Uganda (Haddow et al. 1964), and Aedes furcifer, Aedes luteocephalus, and Aedes africanus in Senegal (Diallo et al. 2014), maintain the African Zika cycle between mosquitoes and arboreal primates. Males of Aedes furcifer caught infected in the wild provide evidence that Zika can be transmitted from an infected female vector to her offspring through the egg stage (Diallo et al. 2014).
Serological investigations showed that human infections with Zika can be common. For example, 40% of an urban population in Nigeria had antibodies to the virus (Fagbami 1979). During spillovers from the forest cycle into domestic or cleared habitats, other Aedes species have been found infected with Zika, such as Aedes metallicus and Aedes vittatus in SE Senegal (Diallo et al. 2014). The epidemiological importance of Zika isolations in Senegal from mosquitoes of other genera, notably species of Mansonia, Culex, and Anopheles, remains unclear (Diallo et al. 2014).
In the invasive range of the virus outside of Africa, the most likely vector of Zika is Aedes aegypti, first recognized as infected in nature in Malaysia (Marchette et al.1969). The preference of domestic Aedes aegypti for feeding on human hosts in tropical cities overrides its inefficiency in developing the ZIKV (Diagne et al. 2015). Aedes albopictus has been implicated as a Zika vector in Gabon (Grard et al. 2014) and has expanded its invasive range worldwide. This finding assumes greater importance because both the mosquito and Zika virus are extending their range and thus it is possible that human-feeding populations of this vector species may co-occur with the emergent virus. In Micronesia, the endemic Aedes hensilli was the probable vector of Zika during the 2007 epidemic of the disease on Yap Island (Duffy et al. 2009).
Which mosquito species native to the Americas might become vectors of Zika remains to be determined by future research. Concern is justified that Zika could become endemic in tropical New World forests, in transmission cycles between arboreal treehole mosquitoes, such as species of Haemagogus and Sabethes, and Neotropical non-human primates, just as occurred in South and Central America for yellow fever virus centuries earlier after its introduction and spread from Africa (Barrett and Higgs 2007). The relative importance of different vector species in the current epidemics in the Americas is unknown, but Aedes aegypti and Aedes albopictus are the most probable transmitters. If confirmed, their capacity to transmit the virus would increase concern in other areas where these species are present.
...
http://edis.ifas.ufl.edu/in1120
--------------------------------------------------------------------------------------------------------------------------
See also:
Canadian mosquito spread of Zika untested
https://flutrackers.com/forum/forum...092-canadian-mosquito-spread-of-zika-untested
Brazilian experts investigate if 'common mosquito' (Culex) is transmitting zika virus
https://flutrackers.com/forum/forum...mon-mosquito-culex-is-transmitting-zika-virus