Nanovaccines against Animal Pathogens: The Latest Findings.

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.

A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations.

Analysing pig class II mayor histocompatibility complex (MHC) molecules is mainly related to antigen presentation. Identifying frequently-occurring alleles in pig populations is an important aspect to be considered when developing peptide-based vaccines. Colombian creole pig populations have had to adapt to local conditions since entering Colombia; a recent census has shown low amounts of pigs which is why they are considered protected by the Colombian government. Commercial hybrids are more attractive regarding production. This research has been aimed at describing the allele distribution of Colombian pigs from diverse genetic backgrounds and comparing Colombian SLA-DRB1 locus diversity to that of internationally reported populations. Twenty SLA-DRB1 alleles were identified in the six populations analysed here using sequence-based typing. The amount of alleles ranged from six (Manta and Casco Mula) to nine (San Pedreño). Only one allele (01:02) having > 5% frequency was shared by all three commercial line populations. Allele 02:01:01 was shared by five populations (around > 5% frequency). Global FST indicated that pig populations were clearly structured, as 20.6% of total allele frequency variation was explained by differences between populations (FST = 0.206). This study's results confirmed that the greatest diversity occurred in wild boars, thereby contrasting with low diversity in domestic pig populations.

Behavior and abundance of Anopheles darlingi in communities living in the Colombian Amazon riverside.

In the past few years, relative frequencies of malaria parasite species in communities living in the Colombian Amazon riverside have changed, being Plasmodium vivax (61.4%) and Plasmodium malariae (43.8%) the most frequent. Given this epidemiological scenario, it is important to determine the species of anophelines involved in these parasites' transmission. This study was carried out in June 2016 in two indigenous communities living close to the tributaries of the Amazon River using protected human bait. The results of this study showed a total abundance of 1,085 mosquitos, of which 99.2% corresponded to Anopheles darlingi. Additionally, only two anopheline species were found, showing low diversity in the study areas. Molecular confirmation of some individuals was then followed by evolutionary analysis by using the COI gene. Nested PCR was used for identifying the three Plasmodium species circulating in the study areas. Of the two species collected in this study, 21.0% of the An. darlingi mosquitoes were infected with P. malariae, 21.9% with P. vivax and 10.3% with Plasmodium falciparum. It exhibited exophilic and exophagic behavior in both study areas, having marked differences regarding its abundance in each community (Tipisca first sampling 49.4%, Tipisca second sampling 39.6% and Doce de Octubre 10.9%). Interestingly, An. mattogrossensis infected by P. vivax was found for the first time in Colombia (in 50% of the four females collected). Analysis of An. darlingi COI gene diversity indicated a single population maintaining a high gene flow between the study areas. The An. darlingi behavior pattern found in both communities represents a risk factor for the region's inhabitants living/working near these sites. This highlights the need for vector control efforts such as the use of personal repellents and insecticides for use on cattle, which must be made available in order to reduce this Anopheline's abundance.