The complex interplay of climate, TBEV vector dynamics and TBEV infection rates in ticks-Monitoring a natural TBEV focus in Germany, 2009-2018

被引：19

作者：

Borde, Johannes P. ^{[1
,2
,3
]}

Kaier, Klaus ^{[4
,5
]}

Hehn, Philip ^{[4
,5
]}

Matzarakis, Andreas ^{[6
]}

Frey, Stefan ^{[7
]}

Bestehorn, Malena ^{[8
]}

Dobler, Gerhard ^{[7
,8
]}

Chitimia-Dobler, Lidia ^{[7
,8
]}

机构：

[1] Univ Freiburg, Div Infect Dis, Dept Med 2, Med Ctr, Freiburg, Germany

[2] Fac Med, Freiburg, Germany

[3] Praxis Dr J Borde Gesundheitszentrum Oberkirch, Oberkirch, Germany

[4] Univ Freiburg, Inst Med Biometry & Stat, Fac Med, Freiburg, Germany

[5] Univ Freiburg, Med Ctr, Freiburg, Germany

[6] Res Ctr Human Biometeorol, German Meteorol Serv, Freiburg, Germany

[7] German Natl Reference Lab TBEV, Bundeswehr Inst Microbiol, Munich, Germany

[8] Univ Hohenheim, Parasitol Unit, Stuttgart, Germany

来源：

PLOS ONE | 2021年 / 16卷 / 01期

关键词：

BORNE ENCEPHALITIS-VIRUS; IXODES-RICINUS TICKS; SOUTHERN GERMANY; RODENTS; PREVALENCE; PATHOGENS; EPIDEMIOLOGY; TRANSMISSION; HUMANS;

D O I：

10.1371/journal.pone.0244668

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Background Tick-borne encephalitis (TBE) is the most important tick-borne viral disease in Eurasia and causes disease in humans and in a number of animals, among them dogs and horses. There is still no good correlation between tick numbers, weather conditions and human cases. There is the hypothesis that co-feeding due to simultaneous occurrence of larvae and nymphs may be a factor for the increased transmission of the virus in nature and for human disease. Based on long-term data from a natural TBEV focus, phylogenetic results and meteorological data we sought to challenge this hypothesis. Methods Ticks from an identified TBE natural focus were sampled monthly from 04/2009 to 12/2018. Ticks were identified and pooled. Pools were tested by RT-qPCR. Positive pools were confirmed by virus isolation and/or sequencing of additional genes (E gene, NS2 gene). Temperature data such as the decadal (10-day) mean daily maximum air temperature (DMDMAT) were obtained from a nearby weather station and statistical correlations between tick occurrence and minimal infection rates (MIR) were calculated. Results In the study period from 04/2009 to 12/2018 a total of 15,530 ticks (2,226 females, 2,268 males, 11,036 nymphs) were collected. The overall MIR in nymphs over the whole period was 77/15,530 (0.49%), ranging from 0.09% (2009) to 1.36% (2015). The overall MIR of female ticks was 0.76% (17/2,226 ticks), range 0.14% (2013) to 3.59% (2016). The overall MIR of males was 0.57% (13/2,268 ticks), range from 0.26% (2009) to 0.97% (2015). The number of nymphs was statistically associated with a later start of spring/vegetation period, indicated by the onset of forsythia flowering. Conclusion There was no particular correlation between DMDMAT dynamics in spring and/or autumn and the MIR of nymphs or adult ticks detected. However, there was a positive correlation between the number of nymphs and the number of reported human TBE cases in the following months, but not in the following year. The hypothesis of the importance of co-feeding of larvae and nymphs for the maintenance of transmission cycle of TBEV in nature is not supported by our findings.

引用

页数：16