Co-infection of Dengue, Zika and Chikungunya in a group of pregnant women from Tuxtla Gutiérrez, Chiapas: Preliminary data. 2019.

INTRODUCTION: Dengue, Zika and Chikungunya are RNA Arboviruses present in some areas of Mexico, mainly in the endemic state of Chiapas that is characterized by presence of the vector that transmit them and an ecology that favors high transmission. According to the national epidemiological surveillance system, Dengue has intensified since 2018 and outbreaks continue in various states while for Zika and Chikungunya a decrease in cases has been reported in recent years. The main objective of this study was to determine the incidence of Dengue, Zika and Chikungunya infections during pregnancy in the state of Chiapas. PRINCIPAL FINDINGS: The presence of previous and current infections and coinfections diagnosed by molecular (RT-PCR) and immunological (ELISA for IgG determination) techniques indicates a wide circulation of viruses in asymptomatic people, specifically in pregnant women showing that silent infections in dry season contributes to the preservation of viruses. CONCLUSIONS: From 136 studied samples, 27.7% tested positive for DENV, 8% for ZIKV and 24.1% for CHIKV by RTPCR and the values of IgG in sera show that 83.9% were positive for IgG antibodies against DENV, 65% against ZIKV and 59.1% against CHIKV. Results demonstrated presence of ZIKV and CHIKV, not detected by the epidemiological surveillance system, so the importance of establishing proactive epidemiological systems more strict, especially because these infections in pregnant women can cause severe health problems for newborn children.

Molecular similarities and differences between Trichinella spp., isolated from canine skeletal muscle in Zacatecas, Mexico.

Four different isolates of Trichinella spp. (Z1, Z2, Z3, and Z4) obtained from the skeletal muscle of street dogs in the state of Zacatecas, Mexico were serial passaged in Wistar rats; infective larvae from the skeletal muscle of the rats were collected and frozen in liquid nitrogen. After centrifugation, DNA was extracted and the 5SRNAr and IsRNAr genes were amplified. The isolates were identified by the size of the amplified products from the 5SRNAr and IsRNAr genes (750 and 290 bp, respectively). The amplicons obtained by PCR were sequenced, aligned, and compared to the reference strain Trichinella spiralis MSUS/MEX/91//EM isolated from pigs. Based on our results, we determined that the Trichinella isolates from canine (Z1-Z4) belonged to the T. spiralis species and had 83% identity with the reference strain. The phylogenetic tree constructed from the sequences showed differences between the isolates from pig and dog. These genetic differences may be related to the immune response of the host or the pathogenicity of the isolates. Therefore, these findings have important epidemiological and public health implications.

Protein profile analysis from advanced third-stage larvae (AdvL3) and adult worms of Gnathostoma binucleatum (Nematoda: Spirurida).

Proteins from crude extracts of advanced third-stage larvae and adult Gnathostoma binucleatum nematode worms showed protein profiles in SDS-PAGE analysis similar to Echinococcus granulosus, Trichinella spiralis, Dipylidium caninum, Ancylostoma caninum, Ascaris lumbricoides and Toxocara canis. The immunoblot analysis of the human serum infected or suspected to be infected with G. binucleatum using the total larvae extract recognized the 40, 60, 80 and 115 kDa proteins and using the total adult worm extract recognized only the 80 and 115 kDa proteins. However, the 115 kDa protein showed cross-reactions with A. caninum, A. lumbricoides, T. canis and D. caninum with human serum positive to gnathostomosis, while the 40 kDa protein was only recognized with the G. binucleatum total larvae extract. The results obtained suggest that the use of antigens from the advanced third-stage larvae of the parasite were best recognized for immunodiagnosis of gnathostomosis.

Gnathostoma binucleatum: excretion-secretion antigen analysis obtained from advanced third-stage larvae in in vitro culture.

The paper describes an introductory characterization of antigenic stimulation of excretion-secretion products (ESP) of Gnathostoma binucleatum advanced third-stage larvae cultured in vitro and proteinases present in this products. Excretory and secretory proteins were obtained after 10 larvae were maintained in 5% CO(2) RPMI medium. The supernatant was collected each week for two months. The proteins were dialyzed, concentrated, and separated in 10% SDS-PAGE gels under reducing conditions and transferred to nitrocellulose paper for immunoblot analyses. G. binucleatum immunized mice serum was used to determine protein antigenicity. Four proteins of 40, 80, 120, and 208 kDa persisted for two months and three proteins, 80, 120, and 208 kDa were recognized for antibodies of mice. In SDS-PAGE gelatin substrate gels ESP resolved as two proteins with molecular weight of 80 and 208 kDa that were sensitive to a metalloproteinase inhibitor, and thus it may be inferred that they might be used for diagnosis of gnathostomiasis.