Assessment of climate change impact on the malaria vector Anopheles hyrcanus, West Nile disease, and incidence of melanoma in the Vojvodina Province (Serbia) using data from a regional climate model

concentration pathways without any storyline behind them [19]. Comparing SRES-A1B and RCPs in terms of the greenhouse gases concentrations, at the end of this century SRES-A1B is the closest to RCP6.0, but for the time horizon used in this study, up to 2030, the difference between any SRES or RCPs are relatively small. Study area and climate The VPS is situated in the northern part of Serbia and the southern part of the Pannonian low- land (18˚510–21˚330E, 44˚370–46˚110N and 75–641 m.a.s.l. (with the Frusˇka Gora Mountain in the south) as it is seen in Fig 1A and 1B). This region is the essential food production area in Serbia with a total surface area of 21,500 km2 and a population of about 2 million. This region has a continental climate, with elements of a sub-humid and warm climate (Cfwbx” according to Ko¨ppen classification [20]). Models and formula used The global and regional climate model. For climate simulations in this study, we used results of the EBU-POM model runs for the SRES-A1B scenario integrated over the period 2001–2030 [21]. The EBU-POM is a two-way, coupled RCM. The atmospheric part is the Eta/ National Centres for Environmental Prediction (NCEP) limited area model (resolution 0.25˚ × 0.25˚ on 32 vertical levels; centred at 41.5˚ N, 15˚ E, with boundaries at ±19.9˚ W–E and ±13.0˚ S–N), while the oceanic part is the POM (resolution 0.20˚ × 0.20˚ on 21 vertical levels). The driving global circulation model (GCM) was the ECHAM5 model [22] coupled with the Max Planck Institute Ocean Model (MPI-OM) [23]. More details about model integrations

and performed bias correction for VPS can be found in the paper by Mihailović et al. [2]. The POM model was set over the Mediterranean Sea without the Black Sea; for other open seas, the sea surface temperature from the GCM was used as a bottom boundary condition. Environmental sampling Mosquito vectors. We used standardised protocols to measure mosquito presence/ absence, density, and infestation by WNV. Data were extracted from dry ice-baited trap sam- ples, collected over 31 years at 166 different sites (745 sampled locations, S1 Table) in the VPS, to infer on the trends of local vector status and virus circulation in mosquitoes. In all years, mosquitoes were sampled from May to September, with different spatial intensity and time- frequency governed by the scale and scope of different research projects. For comparison with climate variables, we extracted data obtained in 10 years (1985–6, 2004–5 and 2010–5) for which a standardised surveillance protocol was in place. These periods have the highest num- ber of particular location-year combinations (S1–S3 Tables). Samples were collected by two different types of dry-ice baited suction traps. During 1985 and 1986 [24,25] by the miniature CDC light trap (CDC) and for 2004 and 2015 by the NS2 trap (our design of dry ice-baited suction trap without light). Both traps were operating with- out a light source (incandescent light proved not to be attractive/repellent for most mosquito species inhabiting the VPS [25]). The CDC trap has 3–5 times stronger suction power (oper-

ated by a 9V battery) than NS2 (operated by 3 x 1.2V batteries), meaning that the increase in density of species observed after 1986 could not be attributed to the change of the type of trap. Traps were operated from the afternoon until the morning of the next day (one trap night), with different periodicity. The specific location of the trap at each site was chosen by experi- enced entomologists to stabilise variation of the collected data. We used three parameters to indicate An. hyrcanus spread and population growth in the period 1985–2015: i) the ratio of positive to total mosquito samplings per year; ii) the number Impact of climate change on malaria vector, West Nile disease, and incidence of melanoma PLOS ONE | https://doi.org/10.1371/journal.pone.0227679 January 15, 2020 4 / 17