Detection of dengue virus serotype 3 in Cajamarca,Peru:Molecular diagnosis and clinical characteristics

Objective:To describe and molecularly characterize an outbreak of dengue virus(DENV)infection in Cajamarca,an Andean region in Peru.Methods:A total of 359 serum samples from patients with acute febrile illness were assessed for the presence of DENV via RT-PCR,ELISA NS1,Ig M and Ig G in Cajamarca,Peru from January 2017 to June 2017.The evaluation of the different diagnostic tests and their applicability was performed.Results:Dengue virus was detected in 24.7%of samples by RTPCR.Meanwhile,serological analysis detected 30.3%positive cases via ELISA NS1 antigen,16.7%via ELISA Ig G and 9.7%via ELISA Ig M.Most of the cases corresponded to DENV-3(77.5%).The use of RT-PCR performed better in primary infections(P<0.01),while detection of ELISA Ig M performed better in secondary infections(P<0.01).The combination of NS1 and Ig M performed better than the other assays in detecting primary(92.5%)and secondary infections(96.6%).The most frequent symptoms associated with fever were headaches,myalgias,and arthralgias across all groups.Conclusions:We report an important outbreak of dengue infection caused by DENV-3 in Cajamarca,Peru.Our findings encourage the use of NS1 antigen and Ig M co-detection.These findings demonstrate an increasing expansion of DENV-3 in Peru and highlight the importance of molecular diagnosis and serotype characterization among the clinically defined dengue cases to strengthen the Peruvian epidemiological surveillance.

Diversity and host assemblage of avian haemosporidians in different terrestrial ecoregions of Peru

Characterizing the diversity and structure of host–parasite communities is crucial to understandingtheir eco-evolutionary dynamics.Malaria and related haemosporidian parasites are responsible forfitness loss and mortality in bird species worldwide.However,despite exhibiting the greatest ornithologicalbiodiversity,avian haemosporidians from Neotropical regions are quite unexplored.Here,we analyze the genetic diversity of bird haemosporidian parasites(Plasmodium andHaemoproteus)in 1,336 individuals belonging to 206 bird species to explore for differences in diversityof parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions.Wedetected 70 different haemosporidian lineages infecting 74 bird species.We showed that 25 out ofthe 70 haplotypes had not been previously recorded.Moreover,we also identified 81 new host–parasite interactions representing new host records for these haemosporidian parasites.Our outcomesrevealed that the effective diversity(as well as the richness,abundance,and Shannon–Weaver index)for both birds and parasite lineages was higher in Amazon basin ecoregions.Furthermore,we also showed that ecoregions with greater diversity of bird species also had highparasite richness,hence suggesting that host community is crucial in explaining parasite richness.Generalist parasites were found in ecoregions with lower bird diversity,implying that the abundanceand richness of hosts may shape the exploitation strategy followed by haemosporidian parasites.These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidianlineages.Further studies analyzing host distribution and specificity of these parasites inthe tropics will provide important knowledge about phylogenetic relationships,phylogeography,and patterns of evolution and distribution of haemosporidian parasites.