Dengue Virus in Bats from Southeastern Mexico

Abstract

Abstract. To identify the relationship between landscape use and dengue virus (DENV) occurrence in bats, we investigated the presence of DENV from anthropogenically changed and unaltered landscapes in two Biosphere Reserves: Calakmul (Campeche) and Montes Azules (Chiapas) in southern Mexico. Spleen samples of 146 bats, belonging to 16 species, were tested for four DENV serotypes with standard reverse transcriptase polymerase chain reaction (RT-PCR) protocols. Six bats (4.1%) tested positive for DENV-2: four bats in Calakmul (two Glossophaga soricina, one Artibeus jamaicensis, and one A. lituratus) and two bats in Montes Azules (both A. lituratus). No effect of anthropogenic disturbance on the occurrence of DENV was detected; however, all three RT-PCR-positive bat species are considered abundant species in the Neotropics and well-adapted to disturbed habitats. To our knowledge, this study is the first study conducted in southeastern Mexico to identify DENV-2 in bats by a widely accepted RT-PCR protocol. The role that bats play on DENV's ecology remains undetermined.Dengue fever is an important public health concern in the tropics, 1-4 and ecological and epidemiological studies are needed to assess the role of bats and other mammals in a possible sylvatic maintenance cycle.5 Dengue viruses (DENVs) comprise four antigenically distinct but genetically related serotypes of the Flavivirus genus (Flaviviridae family). 1DENVs are positive-sense single-stranded RNA viruses that cause one of the most common infectious diseases in humans in tropical regions.2 Their transmission includes an urban endemic/epidemic cycle between Aedes aegypti mosquitoes and humans as the reservoir host and a sylvatic enzootic cycle between non-human primates and arboreal mosquitoes of the genus Aedes.3 The urban cycle is well-documented in the Neotropics, with four serotypes reported in urban areas, 1-4 whereas the sylvatic cycle has been shown in West Africa and peninsular Malaysia.5 Thus far, the sylvatic cycle has not been described in the Neotropics. However, in Bolivia, DENV seroconversions among the indigenous Ayoreo people were found in a remote area where Ae. aegypti, the primary vector, was absent. 6 This finding suggests a possible sylvatic cycle involving a different mosquito species or cross-reaction with antibodies to another flavivirus. In French Guiana, all four DENV serotypes have been identified by molecular methods in 92 wild mammals (bats, rodents, and marsupials) in all settings investigated: periurban, rural, and sparsely populated areas.7 This finding suggests that primarily urban DENV strains could infect wildlife in non-urban forested areas. 7 The role of wildlife in DENV transmission remains unknown.Bats are important reservoirs of many viruses, such as rabies viruses, Nipah viruses, and coronaviruses. [8][9][10][11][12] Flaviviridae are the second most frequently reported viral family in the order Chiroptera (13% frequency; second only to rhabdoviruses) 9 ; however, their role in the dynamics of DENVs remains poorly ...

Experimental Inoculation of Artibeus jamaicensis Bats with Dengue Virus Serotypes 1 or 4 Showed No Evidence of Sustained Replication

“…bats has been reported. 11,13,15 For EI-1, DENV-4, and the subcutaneous route were used in an attempt to generate an initial localized infection of the skin resident cells of the immune system. 2 Skin resident dendritic cells and macrophages are supposed to be first cells encountered by the DENV after a natural infection by a mosquito bite.…”

“…40,41 However, no evidence of viremia, antigenemia or serological immune response was found after EI-1 or EI-2. Analysis of spleen tissue, an organ found to be infected in humans 42 and bats 15 also failed to show evidence of DENV replication. Results obtained with Mock inoculated bats are not present for simplicity.…”

“…[12][13][14] In addition, reverse transcription-polymerase chain reaction (RT-PCR) testing of spleen or heart tissue samples from bats captured in dengue-endemic areas in Mexico, detected the presence of DENV-2 in frugivorous (Artibeus jamaicensis, Artibeus lituratus, Glossophaga soricina) and insectivorous (Myotis nigricans) bats. 13,15 In an elegant study carried out in the French Guiana, RNA corresponding to the 4 DENV serotypes was detected in tissue samples collected from several species of wild mammals. Interestingly, evidence of DENV infection was found in mammals, including several species of Chiroptera, captured in remote sylvatic areas, where no evidence of dengue cycle exists.…”

Analysis of Cathepsin and Furin Proteolytic Enzymes Involved in Viral Fusion Protein Activation in Cells of the Bat Reservoir Host

“…In the past twenty years, bats of different species have been recognized as important hosts of viruses from different families including rhabdoviruses [1][2][3], coronaviruses [4][5][6][7][8][9], filoviruses [10][11][12], flaviviruses [13,14], orthomyxoviruses [15][16][17], paramyxoviruses [18,19] and others [20,21]. Numerous studies have shown that bats not only harbor a large number of viruses, but are also a major source for the emergence and transmission of viruses that cause highly pathogenic infectious diseases in humans, most importantly Severe Acute Respiratory Syndromelike coronavirus (SARS-like CoV) [7], Ebola virus [10,22] and the henipaviruses, Hendra virus [23][24][25][26] and Nipah virus [27][28][29], which are members of the paramyxovirus family.…”

Predicting the Potential Role of Non-human Hosts in Zika Virus Maintenance

“…Genetic evidence was provided that was consistent with the hypotheses that (1) there exist spillover infections from humans to mammals and (2) there exists an enzootic cycle. In Mexico, six bat species have been identified as positives for DENV (Artibeus jamaicensis, Artibeus lituratus, Carollia brevicauda, Myotis nigricans, Pteronotus parnellii and Natalus stramineus) (Aguilar-Setién et al 2008;Machain-Williams et al 2013;Sotomayor-Bonilla et al 2014).…”