Fermer

Maarten Voordouw

The lab of Ecology and Evolution is currently in a state of transition. I am moving to Saskatoon, Canada to start an assistant professorship in the Department of Veterinary Microbiology at the Western College of Veterinary Medicine, which is part of the University of Saskatchewan. I will start a research lab investigating the ecology of Lyme borreliosis in Canada.

 

Domaines de recherche

General interest: My general interest is in the ecology and evolution of host-parasite interactions. I am particularly interested in vector-borne diseases, which include three actors: the pathogen (or parasite), the vertebrate host, and the arthropod vector. Vector-borne diseases such as malaria, dengue and the Zika virus represent a serious challenge to public health. 

Study system: The research of my group is predominantly focussed on the ecology and evolution of Lyme borreliosis (LB). LB is the most common vector-borne disease in the northern hemisphere (~130,000 human cases per year). In Europe, most cases of human LB are caused by two species of spirochete bacteria: Borrelia afzelii and B. garinii. These two species of tick-borne pathogens are both transmitted by the tick Ixodes ricinus but they are adapted to live in different classes of vertebrate hosts. Borrelia afzelii is associated with rodents whereas B. garinii is found mostly in birds. 

  • Genetically diverse pathogen populations:

    Many pathogen populations consist of genetically diverse strains. Genetic diversity of pathogens can have important implications for public health such as vaccine development. The study of this genetic diversity can help with the development of control strategies. Jonas Durand (PhD) found 21 different strains of B. afzelii and B. garinii in ticks on a 1 ha plot near Neuchâtel [1]. Using data from a long-term study (11 years), we have shown that some strains are 10 times more common than others [1, 2] and we want to understand why. Working together with the research group of Lise Gern, we have recently used experimental infections in laboratory mice to show that there is substantial variation in transmission efficiency between strains of B. afzelii [3]. Interestingly, the strains that had higher fitness in the lab were also those strains that were most common in our wild population of I. ricinus ticks [2, 3]. The strain-specific spirochete load in the tick is another important phenotype (see below).

  • Multiple-strain interactions in the athropod vector:

    Arthropod vectors often carry multiple strains of a vector-borne pathogen. These strains have the opportunity to interact inside the arthropod vector. The outcome of these interactions may influence what strains are transmitted from the vector to the population of vertebrate hosts. Jonas Durand (PhD) showed that multiple-strain infections are common in wild I. ricinus ticks [1, 4]. In its natural life cycle, Borrelia spirochetes can spend 8–10 months in the tick in between blood meals. Thus the different strains in a tick have a lot of time to interact with each other. Dolores Genné (PhD candidate) is testing whether Borrelia strains compete inside the tick vector and whether this competition influences the transmission success to the vertebrate host.

  • OspC and strain-specific immunity:

    Immune responses that protect the host from infection can be highly specific for one particular strain. In vertebrate hosts, strain-specific antibody responses often target surface proteins on the pathogen that are highly variable between strains. Identification of immunodominant antigens that mediate strain-specific protective immunity is therefore important for understanding the epidemiology of multiple-strain pathogens and vaccine development. In LB pathogens, outer surface protein C (OspC) is necessary for establishing infection in the vertebrate host. OspC induces a strong antibody response that induces strain-specific protective immunity. Maxime Jacquet (PhD) conducted a vaccination trial with recombinant OspC proteins to confirm this phenomenon in B. afzelii [5]. Local population of B. afzelii and B. garinii each contain 10–11 different ospC alleles [1]. We want to understand what factors maintain this ospC polymorphism. We believe that the ospC gene facilitates super-infection of previously infected reservoir host and would like to test this hypothesis in the future.

  • Genetic variation in host resistance:

    Genetic differences between host individuals can explain variation in resistance/susceptibility to infectious diseases. There is much interest in identifying the genes that are responsible for variation in host resistance. The toll-like receptors (TLR) are a family of innate immune receptors in vertebrates that were recently discovered. Work by Tschirren and colleagues found that genetic variation in toll-like receptor 2 (TLR2) in a wild population of bank voles was associated with variation in B. afzelii infection [6, 7]. Andrea Gomez (PhD candidate) established a breeding population of bank voles and is currently testing whether the TLR2 polymorphism causes variation in B. afzelii infection.

  • Host-specificity of Borrelia pathogens:

    The host specificity of a parasite is arguably its most important feature. Generalist parasites can jump easily between host species whereas specialist parasites are restricted in their host range. The two most common LB pathogens in Europe, B. afzelii and B. garinii are specialized on rodent and bird reservoir hosts, respectively. This host specificity appears to be mediated by the vertebrate complement system [8, 9]. Experimental infections with B. garinii are rare because there is no reliable avian model. Cindy Bregnard (PhD candidate) is currently trying to develop an in vivo model for testing the complement-based host specificity hypothesis of B. afzelii and B. garinii.

  • Spirochete load in the tick:

    The risk of Lyme disease depends on the density of infected nymphs, which is the second blood-seeking stage in the tick life cycle. The spirochete population (or load) in the nymph can range from 1000 to 10000 bacteria [5]. Maxime Jacquet (PhD) recently showed that the population of B. afzelii spirochetes in the tick can decline by 90% over a period of 6 months [5]. Dolores Genné (PhD candidate) is testing how temperature influences this decline in spirochete load over time. Jonas Durand (PhD) showed that strains with the highest spirochete load in wild ticks are the most common in nature [4]. The tick spirochete load appears to be a critical life history trait for the Borrelia pathogen.

  • Manipulation of host phenotype:

    Vector-borne pathogens can manipulate their vertebrate host or arthropod vector to increase their transmission success. Vector-borne pathogens could benefit from manipulating the host choice behaviour of their arthropod vectors to direct the latter to choose competent rather than incompetent hosts. Jérémy Berret (MSc) tested whether Borrelia influenced the attraction of ticks to host odours but found no evidence for adaptive manipulation [10]. Océane Courbat (MSc candidate) is continuing this work with experimentally infected ticks. Research in the USA found that B. burgdorferi can suppress the immunity of laboratory mice [11]. Inès Ben Messaoud (MSc candidate) is testing this phenomenon in B. afzelii. Yating Li (MSc candidate) is currently testing whether B. afzelii can manipulate the antibody response in bank voles to benefit the tick vector.

  • Borrelia infection and host fitness:

    LB is a serious disease in humans but what is the effect of Borrelia pathogens on the fitness of the reservoir host and tick vector? An experimental infection study found no effect of infection with B. burgdorferi on the running behaviour of the white-footed mouse, Peromyscus leucopus [12]. I analysed a long-term mark-recapture data set but found no effect of Borrelia infection on the survival of P. leucopus [13]. I am very interested to test whether Borrelia pathogens influence the reproductive success of their rodent reservoir hosts. Anouk Sarr (technician) is testing whether B. afzelii influences the fitness of its tick vector.

  • Co-feeding transmission:

    Co-feeding transmission of vector-borne pathogens occurs when the vector is transferred directly between arthropod vectors that feed in close proximity to each other on the same host. This mode of transmission has been demonstrated in a number of vector-borne pathogens such as West Nile virus, tick-borne encephalitis virus, and LB pathogens [14]. Our research group has made a number of contributions to co-feeding transmission of LB pathogens [3, 14, 15]. We have shown that co-feeding transmission can vary among strains of B. afzelii [3, 5] and that this phenotype is associated with strains that have high fitness and that are common in nature [2, 3]. An important remaining question is whether nymphs infected via co-feeding transmission as larval ticks are actually infectious to vertebrate reservoir hosts [14]. Alessandro Belli (MSc candidate) has recently shown that such nymphs are infectious for rodent reservoir hosts.

  • References

    1.Durand J, Jacquet M, Paillard L, Rais O, Gern L, Voordouwa MJ: Cross-Immunity and community structure of a multiple-strain pathogen in the tick vector. Appl Environ Microbiol 2015, 81(22):7740-7752.

    2.Durand J, Jacquet M, Rais O, Gern L, Voordouw MJ: Fitness estimates from experimental infections predict the long-term strain structure of a vector-borne pathogen in the field. Evolution Submitted 26/08/2016.

    3. Tonetti N, Voordouw MJ, Durand J, Monnier S, Gern L: Genetic variation in transmission success of the Lyme borreliosis pathogen Borrelia afzelii. Ticks and Tick-borne Diseases 2015, 6(3):334-343.

    4. Durand J, Herrmann C, Genné D, Sarr A, Gern L, Voordouw MJ: Multi-strain infections of the Lyme borreliosis pathogen in the tick vector. Appl Environ Microbiol Submitted 29/07/2016.

    5. Jacquet M, Durand J, Rais O, Voordouw MJ: Cross-reactive acquired immunity influences transmission success of the Lyme disease pathogen, Borrelia afzelii. Infection, Genetics and Evolution 2015, 36:131-140.

    6. Tschirren B, Andersson M, Scherman K, Westerdahl H, Mittl PRE, Raberg L: Polymorphisms at the innate immune receptor TLR2 are associated with Borrelia infection in a wild rodent population. Proceedings of the Royal Society B-Biological Sciences 2013, 280(1759):20130364.

    7. Tschirren B: Borrelia burgdorferi sensu lato infection pressure shapes innate immune gene evolution in natural rodent populations across Europe. Biology Letters 2015, 11(5).

    8. Kurtenbach K, Sewell HS, Ogden NH, Randolph SE, Nuttall PA: Serum complement sensitivity as a key factor in Lyme disease ecology. Infection and Immunity 1998, 66(3):1248-1251.

    9. Kurtenbach K, De Michelis S, Etti S, Schafer SM, Sewell HS, Brade V, Kraiczy P: Host association of Borrelia burgdorferi sensu lato - the key role of host complement. Trends Microbiol 2002, 10(2):74-79.

    10. Berret J, Voordouw MJ: Lyme disease bacterium does not affect attraction to rodent odour in the tick vector. Parasites & Vectors 2015, 8.

    11. Elsner RA, Hastey CJ, Olsen KJ, Baumgarth N: Suppression of long-lived humoral immunity following Borrelia burgdorferi infection. Plos Pathogens 2015, 11(7).

    12. Schwanz LE, Voordouw MJ, Brisson D, Ostfeld RS: Borrelia burgdorferi has minimal impact on the Lyme Disease reservoir host Peromyscus leucopus. Vector-Borne and Zoonotic Diseases 2011, 11(2):117-124.

    13. Voordouw MJ, Lachish S, Dolan MC: The Lyme disease pathogen has no effect on the survival of its rodent reservoir host. PloS ONE 2015, 10(2).

    14. Voordouw MJ: Co-feeding transmission in Lyme disease pathogens. Parasitology 2015, 142(2):290-302.

    15. Jacquet M, Durand J, Rais O, Voordouw MJ: Strain-specific antibodies reduce co-feeding transmission of the Lyme disease pathogen, Borrelia afzelii. Environmental Microbiology 2016, 18(3):833-845.

Zingg S, Dolle P, Voordouw MJ, Kern M. (2018). The negative effect of wood ant presence on tick abundance. Parasites & Vectors 11: article 164. pdf

Grillon A, Westermann B, Cantero P, Jaulhac B, Voordouw MJ, Kapps D, et al. (2017). Identification of Borrelia protein candidates in mouse skin for potential diagnosis of disseminated Lyme borreliosis. Scientific Reports 7: article 16719. pdf

Rieille N, Klaus C, Hoffmann D, Péter O, Voordouw MJ. (2017). Goats as sentinel hosts for the detection of tick-borne encephalitis risk areas in the Canton of Valais, Switzerland. BMC Veterinary Research 13: article 217. pdf

Geiger CC, Bregnard C, Maluenda E, Voordouw MJ, Schmidt BR. (2017). Antifungal treatment of wild amphibian populations caused a transient reduction in the prevalence of the fungal pathogen, Batrachochytrium dendrobatidis. Scientific Reports 7: article 5956. pdf

Belli A, Sarr A, Rais O, Rego ROM, Voordouw MJ. (2017). Ticks infected via co-feeding transmission can transmit Lyme borreliosis to vertebrate hosts. Scientific Reports 7: article 5006. pdf

Durand J, Jacquet M, Rais O, Gern L, Voordouw MJ. (2017). Fitness estimates from experimental infections predict the long-term strain structure of a vector-borne pathogen in the field. Scientific Reports 7: article 1851 pdf

Jacquet M, Genné D, Belli A, Maluenda E, Sarr A, Voordouw MJ. (2017). The abundance of the Lyme disease pathogen Borrelia afzelii declines over time in the tick vector Ixodes ricinus. Parasites & Vectors 10: article 257 pdf

Margos G, et al. (2017). There is inadequate evidence to support the division of the genus Borrelia. International Journal of Systematic and Evolutionary Microbiology 67:1081-1084

Jacquet M, Margos G, Fingerle V, and Voordouw MJ. (2017). Comparison of the lifetime host-to-tick transmission between two strains of the Lyme disease pathogen Borrelia afzelii. Parasites & Vectors 9: article 645 pdf

Heylen D, Sprong H, Krawczyk A, Van Houtte N, Genné D, Gomez-Chamorro A, van Oers K, and Voordouw MJ. (2017). Inefficient co-feeding transmission of Borrelia afzelii in two common European songbirds. Scientific Reports 7: article number 39596 pdf

Durand J, Herrmann C, Genné D, Sarr A, Gern L, and Voordouw MJ. (2017). Multistrain infections of the Lyme borreliosis pathogen in the tick vector. Applied and Environmental Microbiology 83 pdf

Yersin H, Asiimwe C, Voordouw MJ, Zuberbühler K. (2017). Impact of snare injuries on parasite prevalence in wild chimpanzees (Pan troglodytes). International Journal of Primatology. 38:21-30 pdf

Jacquet M, Durand J, Rais O, Voordouw MJ. (2016). Strain-specific antibodies reduce co-feeding transmission of the Lyme disease pathogen, Borrelia afzelii. Environmental Microbiology 18(3): 833-845 pdf

Jacquet M, Durand J, Rais O, Voordouw MJ. (2015). Cross-reactive acquired immunity influences transmission success of the Lyme disease pathogen, Borrelia afzelii. Infection, Genetics and Evolution 36: 131-140 pdf

Durand J, Jacquet M, Paillard L, Rais O, Gern L, Voordouw MJ. (2015). Cross-immunity and community structure of a multiple-strain pathogen in the tick vector. Applied and Environmental Microbiology 81(22): 7740-7752 pdf

Sapsford SJ, Voordouw MJ, Alford RA, Schwarzkopf L. (2015). Infection dynamics in frog populations with different histories of decline caused by a deadly disease. Oecologia 179(4): 1099-1110 pdf

Paillard L, Jones KL, Evans AL, Berret J, Jacquet M, Lienhard R, Bouzelboudjen M, Arnemo JM, Voordouw MJ. (2015). Seroprevalence of tick-borne pathogens in Scandinavian brown bears over two decades. Parasites & Vectors 8:398 pdf

Berret J, Voordouw MJ. (2015). Lyme disease bacterium does not affect attraction to rodent odour in the tick vector. Parasites & Vectors 8:249 pdf

Tonetti N, Voordouw MJ, Durand J, Monnier S, Gern L. (2015). Genetic variation in transmission success of the Lyme borreliosis pathogen Borrelia afzelii. Ticks and Tick-borne Diseases 6: 334-343 pdf

Voordouw MJ, Lachish S, Dolan MC. (2015). The Lyme disease pathogen has no effect on the survival of its rodent reservoir host. PLOS ONE 10(2): e0118265

Voordouw MJ. (2015). Co-feeding transmission in Lyme disease pathogens. Parasitology 142:290-302 pdf

Rieille N, Bressanelli S, Freire CC, Arcioni S, Gern L, Péter O, Voordouw MJ. (2014). Prevalence and phylogenetic analysis of tick-borne encephalitis virus (TBEV) in field-collected ticks (Ixodes ricinus) in southern Switzerland. Parasites & Vectors 7:443 pdf

Herrmann C, Gern L, Voordouw MJ. (2013). Species co-occurrence patterns among Lyme borreliosis pathogens in the tick vector Ixodes ricinus . Applied and Environmental Microbiology 79:7273-7280 pdf

Herrmann C, Voordouw MJ, Gern L. (2013). Ixodes ricinus ticks infected with the causative agent of Lyme disease, Borrelia burgdorferi sensu lato,have higher energy reserves. International Journal of Parasitology 43(6):477-83 pdf

Voordouw MJ, Tupper H, Önder Ö , Devevey G, Graves CJ, Kemps BD, Brisson D. (2013). Reductions in Human Lyme Disease Risk Due to the Effects of Oral Vaccinatoin on Tick-to-Mouse and Mouse-to-Tick Transmission. Vector-Borne and Zoonotic Diseases 13(4):203-14 pdf

Schwanz LE, Voordouw MJ, Brisson D, Ostelfd RS. (2011) . Borrelia burgdorferi Has Minimal Impact on the Lyme Disease Reservoir Host Peromyscus leucopus. Vector-Borne and Zoonotic Diseases  11(2):117-24    pdf

Voordouw MJ, Adama D, Houston B, Govindarajulu P, Robinson J. (2010) . Prevalence of the pathogenic chytrid fungus, Batrachochytrium dendrobatidis, in an endangered population of northern leopard frogs, Rana pipiens. BioMed Central Ecology 10(1):6  pdf

Voordouw MJ, Anholt BR, Taylor PJ and Hurd H. (2009) . Rodent malaria-resistant strains of the mosquito, Anopheles gambiae, have slower populations growth than -susceptibles strains. BioMed Central Evolutionary Biology 9(1):76  pdf

Voordouw MJ, Koella JC, Hurd H. (2008). Intra-specific variation of sperm length in the malaria vector Anopheles gambiae : males with shorter sperm have higher reproductive success. Malaria Journal 7(1):214  pdf

Voordouw MJ, Stebbins G, Robinson HE, Perrot-Minnot MJ, Rigaud T, Anholt BR. (2008) . Genetic variation in the primary sex ratio in populations of the intertidal copepod, Tigriopus californicus, is widespread on Vancouver Island. Evolutionary Ecology Research 10:1007-1023  pdf

Voordouw, MJ, Lambrechts, L, Koella, J. (2008). No maternal effects after stimulation of the melanization response in the yellow fever mosquito Aedes aegypti. Oikos, 117(8):1269-1279  pdf

Voordouw, MJ, Koella, JC, Hurd, H. (2008). Comparison of male reproductive success in malaria-refractory and susceptible strains of Anopheles gambiae. Malaria Journal 7(1):103  pdf

Voordouw MJ, Koella JC. (2007) . Genetic variation of male reproductive success in a laboratory population of Anopheles gambiae. Malaria Journal 6(1):99  pdf

Voordouw MJ, Robinson HE, Anholt BR. (2005). Paternal inheritance of the primary sex ratio in a copepod. Journal of Evolutionary Biology 18:1304-1314  pdf

Voordouw MJ, Robinson HE, Stebbins G, Albert AY, Anholt BR. (2005). Larval density and the Charnov-Bull model of adaptative environmental sex determination in a copepod. Canadian Journal Zoology 83:943-954  pdf

Voordouw MJ, Anholt BR. (2002). Environmental sex determination in a splash pool copepod. Biological Journal of the Linnean Society 76:511-520  pdf

Voordouw MJ, Anholt BR. (2002). Heritability of sex tendency in a Harpacticoid copepod, Tigriopus californicus. Evolution 56(9):1754-1763  pdf

Voordouw MJ. (2001). Inappropriate application of logarithmic transformations for allometric power functions of morphometric data on acanthocephalan worms. Journal of Zoology (London) 255:279-281  pdf

Maarten Voordouw

Professeur assistant

 

maarten.voordouw@unine.ch

+41 32 718 31 14

Bureau A013