Assessing the role of two populations of Aedes japonicus japonicus for Zika virus transmission under a constant and a fluctuating temperature regime.

doi:10.21203/rs.3.rs-17049/v1

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Assessing the role of two populations of Aedes japonicus japonicus for Zika virus transmission under a constant and a fluctuating temperature regime.

https://doi.org/10.21203/rs.3.rs-17049/v1

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published 18 Sep, 2020

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Background Since the huge epidemic of Zika virus (ZIKV) in Brazil in 2015, questions were raised to understand which mosquito species could transmit the virus. Although Aedes aegypti has been described as the main vector, other Aedes species (e.g. Ae. albopictus and Ae. japonicus) which can potentially transmit viruses from the same family (Flavivirus) such as West Nile, dengue and yellow fever, at least under laboratory conditions, have been incriminated as potential vector for ZIKV. Among these, the Asian bush mosquito Ae. japonicus is widely spread with high abundances in Central-Western Europe. In the present study, infection, dissemination and transmission rates of ZIKV (Dak84 strain) in two populations of Ae. japonicus from Switzerland (Zürich) and France (Steinbach, Haut-Rhin) were investigated under constant (27 °C) and fluctuating (14-27 °C, mean 23 °C) temperature regimes.

Results Both populations were positive for ZIKV transmission. Infectious virus particles were present already 7 days post exposure to infectious rabbit blood. The highest amount of Plaque Forming Unit (PFU) (400/female) were recorded 14 days post oral infection in the Swiss population incubated at constant temperature. No difference in term of infection, dissemination and transmission rate were found according to the mosquito population.

Temperature had no effect on infection rate but the fluctuating temperature regime resulted in higher dissemination rates comparing to constant temperature, regardless of the population. Finally, transmission efficiency ranged between 7-23% and 7-10% for the constant temperature and 0-10% and 3-27% under fluctuating temperatures for the Swiss and the French populations, respectively.

Conclusions This is the first work confirming vector competence for ZIKV of Ae. japonicus originating from Switzerland and France under realistic summer temperatures. Considering the continuous spread of this species in the northern part of Europe and its adaptation at cooler temperatures, preventative control measures should be adopted to prevent possible ZIKV epidemics.

Parasitology

Aedes japonicus

fluctuating temperature

vector competence

Zika virus

The invasive bush mosquito Aedes (Hulecoeteomyia) japonicus japonicus (Diptera: Culicidae) (Theobald 1901) first appeared in Europe in 2000 [1] in France. In 2008, Ae. japonicus was first detected in Switzerland [2], in the north-west part of the country from where it spread and became widely established with locally high abundances. Few years later, the species established in other European countries [2] such as Austria, Croatia, Germany, Hungary, Italy, Liechtenstein, the Netherland, Slovenia and Spain [3–8].

According to genetic studies of the populations collected in Europe, it has been postulated that two separate introductions of Ae. japonicus took place with the separation of two clusters (genotype I and II) [9, 10]. The first genotype includes populations from Belgium and southwestern Germany/Switzerland, eastern Austria/Slovenia and southeastern Germany/northwestern Austria whereas genotype II includes specimens from western and northern Germany only [10, 11].

The role of this species as putative vector of arboviruses such as Eastern equine encephalitis virus (EEEV) [12], La Crosse encephalitis virus (LACV) [13], West Nile virus (WNV) [14, 15], dengue virus (DENV), chikungunya virus (CHIKV) [16] and filarial parasites [17] has been well described. Since the large outbreak of Zika virus (ZIKV) in South America [18] in 2015, huge attention was given to investigate which mosquitoes species could be involved in its transmission [19] and how this can vary according to vector populations and virus strains [20–23]. Several Aedes species have been proven to be capable to transmit ZIKV [24] including autochthonous and invasive European species [25–28]. Although Ae. aegypti has been described as the main vector species for ZIKV transmission [24], recent studies have also shown the potential role of an Ae. japonicus population from southwestern Germany in the transmission of a ZIKV strain from Guatemala (Central America) [29].

Since our recent findings have confirmed the potential role of a population of Ae. japonicus from Switzerland for the transmission of Flaviviruses such as WNV, CHIKV and DENV [14, 15], it was urgent to investigate whether ZIKV, which belongs to the same family as WNV and DENV, could also be transmitted by this species and whether this can vary according to mosquito populations and temperatures.

In our study, we have tested one strain of ZIKV from Dakar (DAK84 Senegal, Africa) [30] with populations of Ae. japonicus from Switzerland (Zürich) and from France (Steinbach, Haut-Rhin). Several vector competence indices from orally infected Ae. japonicus females were here investigated: infection (virus presence in abdomen-thorax), dissemination (virus presence in head), transmission (virus presence in saliva) and transmission efficiency (females with positive saliva among tested ones). Two major questions were addressed: i) susceptibility to oral infection with ZIKV of two field-collected Ae. japonicus populations; ii) effect of temperature on ZIKV infection, dissemination and transmission among these Ae. japonicus populations.

Mosquito rearing

Field collected Ae. japonicus were used for this study. Eggs were collected with standard ovitraps baited with germination paper as oviposition substrate [31]. Two different locations were chosen for collection. The first was located in Zürich, Switzerland, with two collection sites, the Schwamendingen cemetery (47°24'5"N 8°34'28"E) and a private garden close to the University of Zürich - Irchel Campus (47°23'45.3"N 8°33'04.6"E). The second location was a private garden (47°49'16.02"N 7°8'59.20"E) in Steinbach (Haut-Rhin, France). Overall, 30 ovitraps were placed in Zürich (10 in the private garden and 20 in the cemetery) and 20 in Steinbach during June-August 2017. Germination papers were changed weekly, stored semi-dry in plastic zip bags for 7 days at room temperature and then placed in plastic trays with 2 liters of deionized water. One day post immersion, hatched larvae were counted, split (400 larvae/tray) and supplemented with yeast tablets (Gayelord Hauser Superlevure, Gayelord Hauser, France) as larval food (2 tablets/tray). If necessary, half a tablet was added few days later. Larvae were incubated at 27 °C with 85% relative humidity (RH) and the adults obtained were kept into polyester cubic netted cages (32.5 × 32.5 × 32.5 cm) (Bugdorm 43030F, MegaViewScienceCo. Ltd., Taichung, Taiwan) under long daylight conditions (16L:8D) including 1 h dusk and 1 h dawn. A 10% sucrose solution was provided daily to the adults as carbohydrate source.

Mosquito infection

Lyophilized ZIKA virus Dak84 strain, isolated in Dakar (GenBank KU955592 [30]) (7.57 log₁₀ TCID₅₀/ml) and provided by Dr. Failloux, Institute Pasteur, Paris (France), was re-suspended into 400 µl of distilled water, then mixed (1:2) with washed heparinized rabbit blood (not older than 24 h) obtained from the slaughterhouse of a private company (H.R. Kyburz AG, Dorfstrasse 32, Lupfig, Switzerland) to obtain a final a titer of 7 log₁₀ TCID₅₀/ml. Finally, phagostimulant (ATP at 5 × 10⁻³ M) was added to each blood meal. Seven to 9 days old females were deprived of sugar 24 h before their exposure to virus-spiked blood as previously described [14]. Briefly, immediately after the preparation of the infectious blood mixture, 3 ml were transferred into a Hemotek feeder (Hemotek Ltd., Lancashire, UK) covered with a pork intestine membrane fixed with a rubber ring. Mosquitoes were aspirated from the rearing cages and transferred into 500 ml plastic bottles (approx. 60 females/bottle) with the top side covered with a fine net through which the mosquitoes were exposed to the Hemotek feeder. After 20 min of exposure to the infectious blood, mosquitoes were anesthetized by placing the bottles at -20 °C for about 4-5 minutes and then transferred onto a petri dish previously layered with a filter paper. The petri dish was kept on an ice pack the whole time to keep the mosquitoes anesthetized. Fully engorged females were collected and placed into a cardboard box cylinder (12 cm diameter and 15 cm length) covered with nets at both sides which in turn was allocated into a bugdorm cage. Freshly engorged mosquitoes (two females/experiment) were collected immediately after blood feeding (Day 0) as well as a small aliquot of the infectious inoculum for further analysis. All the orally fed mosquitoes were incubated under two different climatic conditions: I) constant temperature (27 °C and relative humidity 85%); II) fluctuating temperature (21±7 °C [average 23 °C] with 45–90% relative humidity), reflecting a typical day in northern Switzerland in mid-summer (www.meteoswiss.admin.ch). The photoperiod for both temperatures was the same as above described. Accordingly, there were four different groups of engorged mosquitoes: Steinbach i) at constant and ii) fluctuating temperature; Zürich iii) at constant and iv) fluctuating temperature. At different time points (day 7, 14 and 21 post oral feeding), 30 females from each infection group were collected. Cardboard boxes were placed at -20 °C for 4-5 minutes to anesthetize the survived mosquitoes after which they were transferred onto a petri dish with ice pack as above described and processed for virus detection. From each time point collection we investigated the rate of infection (IR, proportion of females with infected abdomen among tested ones), dissemination (DR, proportion of females with infected heads among infected ones), transmission (TR, proportion of females with infected saliva among the ones with disseminated infection) and transmission efficiency (TE, proportion of females with infectious saliva among all tested ones). All the feeding, manipulation and incubation of ZIKV infected mosquitoes were done in biosafety containment level 3 (BSL3).

Virus detection in abdomen (infection) and head (dissemination)

Survived engorged females were dissected for removal of wings and legs with sterile forceps and the rest of the body (head and abdomen&thorax) stored dry in 1.5 ml Eppendorf tubes at -80 °C until further investigation. Infection and virus dissemination, confirmed by the presence of virus particles in the tissues of abdomen&thorax (body) and heads respectively, was determined from body parts’ homogenates. A Tissue Lyser® II instrument (Qiagen, Hilden, Germany) was used for homogenization, at 25 Hz for 1 minute, followed by 5 min centrifugation at 13,000g at 4 °C as described [14]. Briefly, 300 µl of Eagle’s Minimum Essential Medium (EMEM) (LGC Standard, GmbH, Wesel, Germany) supplemented with 1% antibiotics and fungizone (1000 IU/ml penicillin/streptomycin; 4 µg/ml amphotericin) (Gibco, Thermo Fisher Scientific, Reinach, Switzerland) (EMEM complete), 2% fetal bovine serum [FBS], and one stainless steel bead (3 mm diameter) were added to each tube containing either the head or the body of the individual mosquitoes. 96-well plates layered with VERO cells (30 000 cells/100µl/well) and EMEM complete supplemented with 10% FCS were prepared 1 day prior to cells infection, and incubated at 37 °C with 5% CO_2.When cells were 75-80% confluent, media was removed and 100 µl of serial dilutions of body part homogenates (neat, 1:10, 1:100) was inoculated into the monolayer of VERO cells and incubated for seven days at the same conditions above described. After the incubation period, cells were stained with a crystal violet solution (0.2% of crystal violet in 10% formaldehyde). Briefly, two ml of the crystal violet solution were added to each well followed by 30 minutes incubation at room temperature after which the wells were washed two times with deionized water and the presence of viral particle assessed by detection of cytopathic effects (CPE) under a microscope.

Virus detection and quantification in saliva (transmission)

For saliva collection, after the removal of wings and legs from each survived individual, females’ proboscises were inserted into 20 µl pipette tips filled with five µl of FBS. After 30 minutes salivation, the five µl of FBS with collected saliva were transferred into 1.5 ml Eppendorf tubes containing 45 µl of EMEM complete and hold on ice until all the samples were collected and then frozen at -80 °C.

The presence of infectious virus particles was determined by plaque assay. Briefly, six-well plates layered with 75-80% confluent Vero cells (800‘000 cells/2ml/well) were inoculated with EMEM complete supplemented with 10% FBS 24 hours before incubation with saliva. For the infection, the media was removed from each well and 265 µl of EMEM complete supplemented with 2% FCS were added to each well, followed by 35 µl of the saliva sample giving a total volume of 300 µl/well. The remaining 15 µl of the saliva samples were kept at -80 °C as back up. After one hour incubation at 37 °C, four ml of a 0.5% agarose solution (UltraPure™ Agarose, Invitrogen Life Technologies, UK) in EMEM complete were added to each well without the removal of the inoculum, and all plates incubated at 37 °C with 5% CO₂. At day seven post incubation, the agarose gel was removed and cells were stained by adding two ml of crystal violet solution per well. After 30 min incubation at room temperature, cells were rinsed with water and plaques enumerated.

Statistical analysis

Differences in the rates of infection, dissemination, and transmission between the two temperature conditions (fluctuating 21±7 °C and constant 27 °C) and the two populations of Ae. japonicus were analysed according to logistic regression, whereas the correlation of viral growth (copy number) with time or temperature was analysed according to negative binomial Generalized Linear Model (GLM).

Mosquito infection

Overall, 2,460 Ae. japonicus females were exposed to blood spiked with the ZIKV Dak84 strain, with a final titer of 7.0 PFU/ml, and a total of 739 individuals (450 from Zürich and 289 from Steinbach) were successfully engorged (feeding rates 8-33%).

Virus detection in abdomen (infection) and head (dissemination)

Infection rates (IR) (Table 1), based on the cytopathic effect (CPE) on VERO cells, for the Zürich population of Ae. japonicus incubated at constant temperature, ranged between 83-93% whereas the ones incubated at fluctuating temperatures were 17-77%. Similar was the Steinbach population with a range of 67-100% at constant temperature, and 47-73% at fluctuating temperature. However, logistic regression analyses showed that there were no significant differences neither in the rates of infection between the two populations of Ae. japonicus nor in the infection rate according to the incubation temperature (fluctuating vs constant temperature) and the length of incubation post oral infection (day 7, 14 or 21).

Dissemination rate (DR) among the Zürich population was higher (P=0.019) when females were incubated at fluctuating temperature comparing to constant temperature, ranging between 26-71% and 12-40%, respectively, whereas DR decreased over time (length of incubation 7, 14 and 21 days) (p=0.00006) regardless of the incubation temperature regimes. Fluctuating temperature increased the dissemination rate over time (p=0.009) also for the Steinbach population of Ae. japonicus (32-64%) but not if incubated at constant temperature (20-40%).

Virus detection and quantification in the saliva (transmission)

Infectious virus particles, based on formation of plaque forming unit (PFU) on VERO cells inoculated with saliva, were observed in females from both populations incubated at either constant or fluctuating temperature regimes. No statistical differences were found in the transmission rate between the two populations and between the two temperature regimes. However, a significant difference in transmission rates, according to the length of incubation post blood feeding, was observed for mosquitoes originated from Steinbach (p=0.015) incubated at fluctuating temperature for 21 days.

The peaks of transmission rate (TR) varied between 67-70% and 30-50% in the Zürich population and 25-50% and 11-73% rate for the Steinbach one at constant and fluctuating temperature, respectively (Table 1). Positive saliva samples were observed already at day 7 post oral infection regardless of incubating conditions and origin of the population.

No significant differences were observed for the saliva viral load (number of infectious virus particles/female) according to incubation temperature regime and time in both populations (Fig. 1). Transmission efficiency (TE) (Table 1) was higher among the Zürich population (7-23%) incubated at constant temperature (27 °C) comparing to the Steinbach population (7-10%) when incubated at same temperature. However, at fluctuating temperature (21±7 °C) the Steinbach population was more efficient (3-27%) than the one from Zürich (0-10%). The highest transmission efficiency was already observed 7 days post blood feeding in the Zürich population incubated at constant temperature (23%) and fluctuating temperature (10%) whereas in the Steinbach population the peaks of transmission efficiency was reached 14 days post oral infection at constant (10%) and fluctuating (27%) temperature conditions (Table 1). As shown in Fig.1, saliva titres from disseminated females ranged from 1.4 to 440 PFU/saliva, with the maximum titre recorded for one Ae. japonicus female originated from Zürich and incubated for 14 days at constant temperature (Fig. 1).

To the best of our knowledge, this is the first paper exploring the vector competence of Ae. japonicus for ZIKV under a fluctuating temperature regime [24]. Our results confirm the potential role of Ae. japonicus for ZIKV transmission under laboratory conditions.

Most of the works investigating mosquito vector competence for several pathogens have been carried out under constant temperature regimes, testing several temperature sets to understand the lower degree threshold for virus infections, dissemination and transmission [29, 32–37]. The main concern of running vector competence studies using constant temperature for incubation of infected arthropods is that this not mimicking the real situation in the field where mosquitoes are constantly exposed to fluctuating temperatures. Since arthropods cannot thermoregulate, environmental temperatures play a crucial role on both the ecology and the vectorial capacity of arthropod vectors such as mortality rate, length of the gonotrophic cycle, biting rate, etc.

Temperature has also a large impact on the amplification of pathogens inside the arthropod body. The length of time required for a pathogen to reach the salivary gland after the intake of an infectious blood meal, the so-called extrinsic incubation period (EIP), is indeed largely regulated by temperature [38, 39]. A linear correlation between the EIP and temperature is described, with higher temperatures increasing the speed of viral replication, infection and transmission (shorter EIP). Lower temperatures increase the length of the EIP, with an implication on the efficiency of being a vector [36, 40]. However, most of the time this has been demonstrated under laboratory conditions where commonly constant temperatures were applied and not fluctuating ones. Some studies on Culex species infected with WNV have shown that fluctuating temperature regime have no impact on the rate of the EIP comparing to constant mean daily temperature [40, 41]. However, recent papers have actually demonstrated that even under a fluctuating temperature regime, there is an important difference when the diurnal temperature range (DTR) is large (20 °C) or moderate (10 °C) [42] and that this can also affect the EIP. The authors describe a lower midgut infection at large DTR comparing to midgut infection observed under moderate DTR for Ae. aegypti infected with two DENV serotypes, despite average temperatures were the same (26 °C).

In our study, a fluctuating temperature regime with a DTR of 14 °C and a mean of 23 °C has shown to increase virus dissemination rate comparing to a constant temperature of 27 °C among ZIKV infected Ae. japonicus regardless of the population used. Transmission efficiency was also higher at these settings but only for the French population whereas the Swiss one had higher transmission efficiency when incubated at constant temperature. Overall, no significant differences for infection, transmission and dissemination were observed between the two populations, and they both show to be potentially capable to transmit the ZIKV strain here tested. These results are in contrast with a recent study investigating ZIKV transmission for a population of Ae. japonicus from Germany, where three temperatures were tested (constant 21, 24 and 27 °C) for an incubation period of 14 days. In this work [29], transmission was observed only at 27 °C. Dissemination was detected at 24 and 27 °C with the highest rate at 24 °C but higher virus titer at 27° C. Midgut infection was recorded at all the three temperatures with the lowest rate at 21 °C.

Despite in our study we have recorded transmission of ZIKV at a mean temperature of 23 °C, we can infer that in the German population other parameters must have been involved on preventing dissemination of the virus within the mosquito’s body parts. Indeed, it is not the first time that the Swiss population (Zürich) of Ae. japonicus is more competent than a population from Germany (Stuttgart) [11] when exposed to the same virus (WNV) [14, 15, 43]. In this previous study [43], the population from Germany was totally negative for WNV infection after 14 days post oral exposure to infectious blood. On the other hand, another population of the same species originating from the United States [44] was found capable of WNV transmission under laboratory conditions when incubated at 26 °C. The authors have speculated that differences in genetic background between Ae. japonicus populations from Germany and North America are most likely responsible for the differences in vector competence for WNV [43]. Indeed, vector competence is very much controlled by several factors including the genetic background of the mosquito species which can vary between different populations and the pathogen strain used [45]. We can consider that the Swiss, the French and the German populations of Ae. japonicus were derived from the same introduction since they were collected from a continuous colonized area, probably originating from Switzerland [2]. Genetic analyses of German and Swiss populations of Ae. japonicus have described the Swiss one as more closely related to the one from southern Germany (Waldshut-Tiengen, Baden-Württemberg) rather than the northern one from Bonn [43]. Thus, the different susceptibility to virus transmission between the Swiss and the Southern Germany (Stuttgart) populations might no be a genetically driven effect. Clearly, more investigations are required to assess the influence of the type of assay used, general methodologies applied during the experiments and the strain of ZIKV used for oral infection. In our work we have used a highly virulent ZIKV strain (DAK84 GenBank accession number KU955592) [30, 46] from Senegal, very closely related to another strain (GenBank accession number KU955591) originated from the same area (Dakar, Senegal) [47, 48] that has previously demonstrated to be successfully transmitted by Ae. aegypti under laboratory conditions [50]. The work from Jansen et al. [29] was carried out using a strain from Guatemala (Mexico) (GenBank accession number KU870645) [50] closed related to another ZIKV strain (GenBank accession number KX247632) (Barrows unpublished) [51] which already showed to be not very infectious for mosquitoes since Ae. aegypti originated from Brazil and USA orally exposed to this strain were negative in the saliva [24, 49]. However, a very recent paper has shown efficient transmission among Ae. aegypti infected with another strain of ZIKV isolated from field infected mosquitoes originating from Mexico although no sequencing of this strain was given [52].

As we have here demonstrated, the pathogen-vector interaction and consequences on virus transmission is a very complex aspect that needs to be taken in high consideration when assessing vector competence of a mosquito species.

With our work, we have shown that two populations of Ae. japonicus from the western part of Europe (Switzerland and France) are potentially capable to transmit ZIKV at realistic fluctuating temperatures between 14 and 27 °C with a mean of 23 °C suggesting that there is a risk for ZIKV transmission in these areas and that preventative measures to control the spread and suppress populations of the invasive Ae. japonicus should be envisaged.

Our study confirms that both investigated populations of Ae. japonicus potentially transmit Zika virus under Central European summer conditions. Despite no differences were detected in term of infection, dissemination and transmission rates among the two populations for the two temperature regimes, we proved that dissemination increases when mosquitoes are incubated under fluctuating temperature compared to constant one. More attention should be given to the strain of virus used and the population of mosquitoes exposed to these strains in order to evaluate the impact that the genetic make-up of both the virus and the vectors can have on assessing the role of a vector and possible implications on the onset of ZIKV epidemics in Europe.

WNV – West Nile virus; EEEV – Eastern Equine Encephalitis virus; LCV – La Cross virus; DENV – Dengue virus; CHIKV – Chikungunya virus; ZIKV – Zika virus; VERO – Vero cells, African green monkey kidney cells; EMEM – Eagle’s Minimum Essential Medium; FCS – Foetal calf serum; CPE – Cytopathic effect; TCID₅₀/ml – 50% Tissue culture infectious dose; IR – Infection Rate; DR – Dissemination Rate; TR – Transmission Rate; dpi – days post infection; BSL3 – Biosafety Security Level 3; LASC – Laboratory Animal Service Centre; PFU- Plaque-forming unit; GLM – Generalized Linear Model; GenBank – Open access sequence database.

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. All data generated or analysed during this study are included in this published articles and its additional files.

Competing interests

The authors declare that they have no competing interests.

Funding

The study was funded by the Staatssekretariat für Bildung Forschung und Innovation (SBFI, CH) Vertragsnummer 17.0009-1 as a contribution to the participation of the research project ZIKAlliance in the frame of the European Union’s Horizon 2020 Research and Innovation Programme (ZIKAlliance 734548).

Authors’ contribution

EV conceived and designed the study. UG, JV collected mosquitoes in the field in Zürich, performed laboratory rearing of mosquitoes, oral infection and processed samples. AP was involved in mosquito’s oral infection, saliva collection and dissection. JH processed samples and carried out mosquito rearing. PT carried out the statistical analyses. FS provided eggs from Steinbach. EV and UG analysed the results and drafted the manuscript. All authors edited, read and approved the final manuscript.

We kindly thank Alexander Mathis (Institute of Parasitology, Zürich, Switzerland) for valuable comments on the manuscript, Anna-Bella Failloux (Institut Pasteur, Paris, France) for providing the Zika virus in the frame of the European Union’s Horizon 2020 Research and Innovation Programme under ZIKAlliance Grant Agreement no. 734548. The authors are very grateful to the Animal Laboratory Service Centre (LASC) at Irchel, University of Zürich, to make available the BSL3 facility. We highly acknowledge the Bundesamt für Lebensmittelsicherheit und Veterinärwesen (Switzerland) for financial support of the National Centre for Vector Entomology.

Schaffner F, Chouin S, Guilloteau J: First record of Ochlerotatus (Finlaya) japonicus japonicus (Theobald, 1901) in metropolitan France. Journal of the American Mosquito Control Association 2003, 19(1):1-5.
Schaffner F, Kaufmann C, Hegglin D, Mathis A: The invasive mosquito Aedes japonicus in Central Europe. Med Vet Entomol 2009, 23(4):448-451.
Seidel B, Nowotny N, Bakonyi T, Allerberger F, Schaffner F: Spread of Aedes japonicus japonicus (Theobald, 1901) in Austria, 2011-2015, and first records of the subspecies for Hungary, 2012, and the principality of Liechtenstein, 2015. Parasit Vectors 2016, 9(1):356.
Ibáñez-Justicia A, Kampen H, Braks M, Schaffner F, Steeghs M, Werner D, Zielke DE, Den Hartog W, Brooks MB, Dik M et al: First report of established population of Aedes japonicus japonicus (Theobald, 1901) (Diptera, Culicidae) in the Netherlands. Journal of the European Mosquito Control Association 2014, 32:9-13.
Klobucar A, Lipovac I, Zagar N, Mitrovic-Hamzic S, Tesic V, Vilibic-Cavlek T, Merdic E: First record and spreading of the invasive mosquito Aedes japonicus japonicus (Theobald, 1901) in Croatia. Med Vet Entomol 2019, 33(1):171-176.
Versteirt V, Schaffner F, Garros C, Dekoninck W, Coosemans M, Van Bortel W: Introduction and establishment of the exotic mosquito species Aedes japonicus japonicus (Diptera: Culicidae) in Belgium. Journal of Medical Entomology 2009, 46(6):1464-1467.
Scholte EJ, Schaffner F: Waiting for the tiger: Establishment and spread of the Aedes albopictus mosquito in Europe. In: Emerging pests and vector-borne diseases in Europe Edited by Takken W, Knols BGJ, vol. 1: Wageningen Academic Publishers; 2007: 241-260.
Dalla Pozza G, Majori G: First record of Aedes albopictus establishment in Italy. Journal of the American Mosquito Control Association 1992, 8(3):318-320.
Koban MB, Kampen H, Scheuch DE, Frueh L, Kuhlisch C, Janssen N, Steidle JLM, Schaub GA, Werner D: The Asian bush mosquito Aedes japonicus japonicus (Diptera: Culicidae) in Europe, 17 years after its first detection, with a focus on monitoring methods. Parasit Vectors 2019, 12(1):109.
Zielke DE, Werner D, Schaffner F, Kampen H, Fonseca DM: Unexpected patterns of admixture in German populations of Aedes japonicus japonicus (Diptera: Culicidae) underscore the importance of human intervention. PLoS One 2014, 9(7):e99093.
Zielke DE, Ibanez-Justicia A, Kalan K, Merdic E, Kampen H, Werner D: Recently discovered Aedes japonicus japonicus (Diptera: Culicidae) populations in The Netherlands and northern Germany resulted from a new introduction event and from a split from an existing population. Parasit Vectors 2015, 8:40.
Sardelis MR, Dohm DJ, Pagac B, Andre RG, Turell MJ: Experimental transmission of eastern equine encephalitis virus by Ochlerotatus j. japonicus (Diptera: Culicidae). Journal of Medical Entomology 2002, 39(3):480-484.
Sardelis MR, Turell MJ, Andre RG: Laboratory transmission of La Crosse virus by Ochlerotatus j. japonicus (Diptera: Culicidae). Journal of Medical Entomology 2002, 39(4):635-639.
Veronesi E, Paslaru A, Silaghi C, Tobler K, Glavinic U, Torgerson P, Mathis A: Experimental evaluation of infection, dissemination, and transmission rates for two West Nile virus strains in European Aedes japonicus under a fluctuating temperature regime. Parasitol Res 2018, 117(6):1925-1932.
Wagner S, Mathis A, Schonenberger AC, Becker S, Schmidt-Chanasit J, Silaghi C, Veronesi E: Vector competence of field populations of the mosquito species Aedes japonicus japonicus and Culex pipiens from Switzerland for two West Nile virus strains. Med Vet Entomol 2018, 32(1):121-124.
Schaffner F, Vazeille M, Kaufmann C, Failloux AB, Mathis A: Vector competence of Aedes japonicus for chikungunya and dengue viruses. European Mosquito Bullettin 2011, 29:141-142.
Silaghi C, Beck R, Capelli G, Montarsi F, Mathis A: Development of Dirofilaria immitis and Dirofilaria repens in Aedes japonicus and Aedes geniculatus. Parasit Vectors 2017, 10(1):94.
Zanluca C, Melo VC, Mosimann AL, Santos GI, Santos CN, Luz K: First report of autochthonous transmission of Zika virus in Brazil. Mem Inst Oswaldo Cruz 2015, 110(4):569-572.
Boyer S, Calvez E, Chouin-Carneiro T, Diallo D, Failloux AB: An overview of mosquito vectors of Zika virus. Microbes Infect 2018, 20(11-12):646-660.
Pompon J, Morales-Vargas R, Manuel M, Huat Tan C, Vial T, Hao Tan J, Sessions OM, Vasconcelos PDC, Ng LC, Misse D: A Zika virus from America is more efficiently transmitted than an Asian virus by Aedes aegypti mosquitoes from Asia. Sci Rep 2017, 7(1):1215.
Ciota AT, Bialosuknia SM, Zink SD, Brecher M, Ehrbar DJ, Morrissette MN, Kramer LD: Effects of Zika virus strain and Aedes mosquito species on vector competence. Emerg Infect Dis 2017, 23(7):1110-1117.
Hery L, Boullis A, Delannay C, Vega-Rua A: Transmission potential of African, Asian and American Zika virus strains by Aedes aegypti and Culex quinquefasciatus from Guadeloupe (French West Indies). Emerg Microbes Infect 2019, 8(1):699-706.
Chouin-Carneiro T, Vega-Rua A, Vazeille M, Yebakima A, Girod R, Goindin D, Dupont-Rouzeyrol M, Lourenco-de-Oliveira R, Failloux AB: Differential dusceptibilities of Aedes aegypti and Aedes albopictus from the Americas to Zika virus. PLoS Negl Trop Dis 2016, 10(3):e0004543.
Epelboin Y, Talaga S, Epelboin L, Dusfour I: Zika virus: An updated review of competent or naturally infected mosquitoes. PLoS Negl Trop Dis 2017, 11(11):e0005933.
Boccolini D, Toma L, Di Luca M, Severini F, Romi R, Remoli ME, Sabbatucci M, Venturi G, Rezza G, Fortuna C: Experimental investigation of the susceptibility of Italian Culex pipiens mosquitoes to Zika virus infection. Euro Surveill 2016, 21(35).
Di Luca M, Severini F, Toma L, Boccolini D, Romi R, Remoli ME, Sabbatucci M, Rizzo C, Venturi G, Rezza G et al: Experimental studies of susceptibility of Italian Aedes albopictus to Zika virus. Euro Surveill 2016, 21(18).
Nunez AI, Talavera S, Aranda C, Birnberg L, Rivas R, Pujol N, Verdun M, Failloux AB, Busquets N: European Aedes caspius mosquitoes are experimentally unable to transmit Zika virus. Parasit Vectors 2019, 12(1):363.
Heitmann A, Jansen S, Luhken R, Leggewie M, Badusche M, Pluskota B, Becker N, Vapalahti O, Schmidt-Chanasit J, Tannich E: Experimental transmission of Zika virus by mosquitoes from central Europe. Euro Surveill 2017, 22(2).
Jansen S, Heitmann A, Luhken R, Jost H, Helms M, Vapalahti O, Schmidt-Chanasit J, Tannich E: Experimental transmission of Zika virus by Aedes japonicus japonicus from southwestern Germany. Emerg Microbes Infect 2018, 7(1):192.
Atieh T, Baronti C, de Lamballerie X, Nougairede A: Simple reverse genetics systems for Asian and African Zika viruses. Sci Rep 2016, 6:39384.
Balestrino F, Schaffner F, Forgia DL, Paslaru AI, Torgerson PR, Mathis A, Veronesi E: Field evaluation of baited traps for surveillance of Aedes japonicus japonicus in Switzerland. Med Vet Entomol 2016, 30(1):64-72.
Tesla B, Demakovsky LR, Mordecai EA, Ryan SJ, Bonds MH, Ngonghala CN, Brindley MA, Murdock CC: Temperature drives Zika virus transmission: Evidence from empirical and mathematical models. Proc Biol Sci 2018, 285(1884).
Vogels CBF, Goertz GP, Pijlman GP, Koenraadt CJM: Vector competence of northern and southern European Culex pipiens pipiens mosquitoes for West Nile virus across a gradient of temperatures. Med Vet Entomol 2017, 31(4):358-364.
Vogels CB, Fros JJ, Goertz GP, Pijlman GP, Koenraadt CJ: Vector competence of northern European Culex pipiens biotypes and hybrids for West Nile virus is differentially affected by temperature. Parasit Vectors 2016, 9(1):393.
Leggewie M, Badusche M, Rudolf M, Jansen S, Borstler J, Krumkamp R, Huber K, Kruger A, Schmidt-Chanasit J, Tannich E et al: Culex pipiens and Culex torrentium populations from Central Europe are susceptible to West Nile virus infection. One Health 2016, 2:88-94.
Kilpatrick AM, Meola MA, Moudy RM, Kramer LD: Temperature, viral genetics, and the transmission of West Nile virus by Culex pipiens mosquitoes. PLoS Pathog 2008, 4(6):e1000092.
Reisen WK, Fang Y, Martinez VM: Effects of temperature on the transmission of West Nile virus by Culex tarsalis (Diptera: Culicidae). Journal of Medical Entomology 2006, 43(2):309-317.
Chamberlain RW, Sudia WD: Mechanism of transmission of viruses by mosquitoes. Annual Review of Entomology 1961, 6:371-390.
Hardy JL, Houk EJ, Kramer LD, Reeves WC: Intrinsic factors affecting vector competence of mosquitoes for arboviruses. Annual Review of Entomology 1983, 28:229-262.
Danforth ME, Reisen WK, Barker CM: The impact of cycling temperature on the transmission of West Nile virus. Journal of Medical Entomology 2016, 53(3):681-686.
Cornel AJ, Jupp PG, Blackburn NK: Environmental temperature on the vector competence of Culex univittatus (Diptera: Culicidae) for West Nile virus. Journal of Medical Entomology 1993, 30(2):449-456.
Lambrechts L, Paaijmans KP, Fansiri T, Carrington LB, Kramer LD, Thomas MB, Scott TW: Impact of daily temperature fluctuations on dengue virus transmission by Aedes aegypti. Proc Natl Acad Sci U S A 2011, 108(18):7460-7465.
Huber K, Jansen S, Leggewie M, Badusche M, Schmidt-Chanasit J, Becker N, Tannich E, Becker SC: Aedes japonicus japonicus (Diptera: Culicidae) from Germany have vector competence for Japan encephalitis virus but are refractory to infection with West Nile virus. Parasitol Res 2014, 113(9):3195-3199.
Turell MJ, O'Guinn ML, Dohm DJ, Jones JW: Vector competence of North American mosquitoes (Diptera: Culicidae) for West Nile virus. Journal of Medical Entomology 2001, 38(2):130-134.
Vazeille M, Zouache K, Vega-Rua A, Thiberge JM, Caro V, Yebakima A, Mousson L, Piorkowski G, Dauga C, Vaney MC et al: Importance of mosquito "quasispecies" in selecting an epidemic arthropod-borne virus. Sci Rep 2016, 6.
Ladner JT, Wiley MR, Prieto K, Yasuda CY, Nagle E, Kasper MR, Reyes D, Vasilakis N, Heang V, Weaver SC et al: Complete genome sequences of five Zika virus isolates. Genome Announc 2016, 4(3).
Gong Z, Xu X, Han GZ: The Diversification of Zika Virus: Are there two distinct lineages? Genome Biol Evol 2017, 9(11):2940-2945.
Gorman MJ, Caine EA, Zaitsev K, Begley MC, Weger-Lucarelli J, Uccellini MB, Tripathi S, Morrison J, Yount BL, Dinnon KH, 3rd et al: An immunocompetent mouse model of Zika virus infection. Cell Host Microbe 2018, 23(5):672-685 e676.
Roundy CM, Azar SR, Rossi SL, Huang JH, Leal G, Yun R, Fernandez-Salas I, Vitek CJ, Paploski IA, Kitron U et al: Variation in Aedes aegypti mosquito competence for Zika virus transmission. Emerg Infect Dis 2017, 23(4):625-632.
Driggers RW, Ho CY, Korhonen EM, Kuivanen S, Jaaskelainen AJ, Smura T, Rosenberg A, Hill DA, DeBiasi RL, Vezina G et al: Zika virus infection with prolonged maternal viremia and fetal brain abnormalities. N Engl J Med 2016, 374(22):2142-2151.
Dupont-Rouzeyrol M, Diancourt L, Calvez E, Vandenbogaert M, O'Connor O, Teissier A, Pol M, Aubry M, Faye O, Tou D et al: Zika virus evolution on the edges of the Pacific ocean. Emerg Microbes Infect 2017, 6(12):e111.
Elizondo-Quiroga D, Ramirez-Medina M, Gutierrez-Ortega A, Elizondo-Quiroga A, Munoz-Medina JE, Sanchez-Tejeda G, Gonzalez-Acosta C, Correa-Morales F: Vector competence of Aedes aegypti and Culex quinquefasciatus from the metropolitan area of Guadalajara, Jalisco, Mexico for Zika virus. Sci Rep 2019, 9(1):16955.

Table 1. Proportion (rates) of Aedes japonicus females from Zürich (Switzerland), positive to ZIKV in the abdomen (infection), head (dissemination) and saliva (transmission) after feeding on ZIKV-spiked blood.

Dpi¹

IR²

(%)

DR³

(%)

TR⁴

(%)

TE⁵

(%)

95% CI⁶

95% CI

25/30

(83)

65-94%

14/30

(47)

28-66%

10/25

(40)

21-61%

10/14

(71)

42-92%

7/10

(70)

35-93%

3/10

(30)

7-65%

7/30

(23)

1-42%

3/30

(10)

2-26%

28/30

(93)

78-99%

5/30

(17)

6-35%

9/28

(32)

16-52%

3/5

(60)

15-95%

6/9

(67)

30-92%

0/3

(0)

0-7%

6/30

(20)

8-38%

0/30

(0)

0-11%

26/30

(87)

69-96%

23/30

(77)

58-90%

3/26

(12)

2-30%

6/23

(26)

10-48%

2/3

(67)

9-99%

3/6

(50)

12-88%

2/30

(7)

0.8-22%

3/30

(10)

2-26%

¹Dpi: days post oral feeding; C: constant temperature (27 °C); F: fluctuating temperature (21±7 °C)

²IR: (infection rate): proportion of survived mosquitoes containing infectious virus particles in the abdomen

³DR: (dissemination rate): proportion of survived mosquitoes containing infectious virus particles in the head among infected ones

⁴TR: (transmission rate): proportion of survived mosquitoes containing infectious virus particles in the saliva among those with disseminated infection

⁵TE: (transmission efficiency): proportion of females with positive saliva among all tested ones

⁶95%CI: confidence interval

Table 2. Proportion (rates) of Aedes japonicus females from Steinbach (France) positive to ZIKV in the abdomen (infection), head (dissemination) and saliva (transmission) after feeding on ZIKV-spiked blood.

Dpi¹

IR²

(%)

DR³

(%)

TR⁴

(%)

TE⁵

(%)

95% CI

20/30

(67)

47-83%

22/30

(73)

54-88%

8/2

(40)

19-64%

7/22

(32)

14-55%

2/8

(25)

3-65%

3/7

(43)

10-81%

2/30

(7)

0.8-22%

3/30

(10)

2-26%

30/30

(100)

88-100%

18/30

(60)

40-77%

6/60

(20)

8-38%

11/18

(61)

36-83%

3/6

(50)

12-88%

8/11

(73)

40-94%

3/30

(10)

2-26%

8/30

(27)

12-46%

20/30

(67)

47-83%

14/30

(47)

28-66%

5/20

(25)

9-49%

9/14

(64)

35-87%

2/5

(40)

5-85%

1/9

(11)

0.2-48%

2/30

(7)

0.8-22%

1/30

(3)

0.08-17%

¹Dpi: days post oral feeding; C: constant temperature (27 °C); F: fluctuating temperature (21±7 °C)

²IR: (infection rate): proportion of survived mosquitoes containing infectious virus particles in the abdomen

³DR: (dissemination rate): proportion of survived mosquitoes containing infectious virus particles in the head among infected ones

⁴TR: (transmission rate): proportion of survived mosquitoes containing infectious virus particles in the saliva among those with disseminated infection

⁵TE: (transmission efficiency): proportion of females with positive saliva among all tested ones

⁶95%CI: confidence interval

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Assessing the role of two populations of Aedes japonicus japonicus for Zika virus transmission under a constant and a fluctuating temperature regime.

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