Parasites and Viruses in Callithrix in Brazil.

PURPOSE: As a result of environmental imbalances of anthropogenic origin, the potential for transmission of parasites and viruses between different primates, including humans, might increase. Thus, parasitic studies have great relevance to primatology, which motivated us to conduct a literature review to synthesize the information available in American primates of the Callithrix genus. METHODS: We carried out the bibliographic search on the main groups of parasites (protozoa, helminths, arthropods, ectoparasites) and viruses found in Callithrix in Brazil in search platforms and consider all manuscript that appeared in search engines, published between the years 1910 and December 2022. In each selected article, the following information was recorded: the host species; parasite taxa; scientific classification of the parasite; host habitat (free-living, captive); diagnostic technique; state; and bibliographic reference. Data were tabulated and arranged in a parasite-host table. RESULTS: Some endemic genera, such as Callithrix, are widely distributed geographically across Brazil and have characteristics of adaptation to different habitats due to their flexibility in diet and behavior. These factors can make them subject to a greater diversity of parasites and viruses in the country. Here, we identified 68 parasitic taxa, belonging to the clades protozoa (n = 22), helminths (n = 34), ectoparasites (n = 7), and viruses (n = 5). Out of this total, 19 have zoonotic potential. Of the six existing marmoset species, Callithrix jacchus was the most frequent in studies, and Callithrix flaviceps did not have reports. All regions of the country had occurrences, mainly the Southeast, where 54% of the cases were reported. In 46% of the reported parasites and viruses, it was not possible to identify the corresponding species. CONCLUSION: We conclude that in part of the works the identification methods are not being specific, which makes it difficult to identify the species that affects Callithrix spp. Furthermore, the studies present geographic disparities, being concentrated in the southeast of the country, making it impossible to have a more uniform analysis of the findings. Thus, it is observed that information about parasites and viruses is incipient in the genus Callithrix in Brazil.

Why Are We Still a Worm World in the 2020s? An Overview of Risk Factors and Endemicity for Soil-Transmitted Helminthiasis.

PURPOSE: Soil-transmitted helminthiasis (STH) is one of the most common chronic infections in developing countries associated with poor socioeconomic and sanitary conditions. The main objective of this overview was to evaluate the influence of environmental factors, risk factors related to the host, and control strategies on the prevalence of STH in different regions of the world. METHODS: LILACS, PubMed, Web of Knowledge, Embase, the Cochrane Library, and Clinical Trials (gray literature) databases were used to obtain the systematic reviews published until December 2020. The methodological quality of systematic reviews was assessed using the standard criteria recommended by AMSTAR. RESULTS: The initial results of the bibliographic search identified 1448 articles, of which 66 studies were read in full and 16 met the inclusion criteria. All the reviews included in this overview associated variations in the global prevalence of STH with at least one of the factors related to the environment, host, and/or control strategies. Climate, temperature, soil moisture, precipitation, mass drug administration, lack of access to water, sanitation and hygiene (WASH), and non-use of footwear were considered the main factors associated with the prevalence of STH. Socioeconomic factors, low educational level, and wearing shoes were universal factors related to prevalence, regardless of the location studied. CONCLUSION: The combination of environmental factors, with factors associated with hosts that predispose infection and reinfection of helminths, as well as the adoption of control strategies based on the treatment of target populations instead of the entire population, influenced the prevalence of STH in all the continents evaluated.

Gastrointestinal parasites in free-ranging common marmosets (Callithrix jacchus Linnaeus, 1758) in the state of Sergipe, northeastern Brazil.

Ecological interactions resulting from human interference and environmental changes have implications for human health and the host animals involved in the parasite cycles. Considering the scarcity of surveys of the parasitic fauna of non-human primates in northeastern Brazil, the objective of this study was to investigate the infection by gastrointestinal parasites in free-ranging common marmosets (Callithrix jacchus) in the State of Sergipe. Fecal samples were collected from 52 animals captured in three protected areas. Most of the samples consisted of adult females and 57% were infected with at least one of the 12 identified parasite taxa. The most frequent intestinal parasite was Prosthenorchis sp., followed by Spiruridae, Entamoeba spp. and Strongylida order. The presence of gastrointestinal parasites was not dependent on sex, age or weight, although there was an association with the capture biome.

Increased Repellent Effect of DEET on Aedes aegypti (Diptera: Culicidae) Field Population.

Insecticides and repellents are routinely used in Brazil because of the high rates of arbovirus transmission and the nuisance caused by mosquitoes. However, few studies have assessed the effectiveness of repellents against mosquito populations that have been under exposure to xenobiotics, mainly insecticides and repellents. This study investigated the sensitivity of a field population of Aedes aegypti (Linnaeus, 1762) from a dengue-endemic area under high insecticide pressure to N,N-diethylmethylbenzamide (DEET), the active ingredient in common repellent products. The field (Laranjeiras, Sergipe, Brazil) and laboratory (Rockefeller) populations were characterized for the presence of the Val1016Ile kdr mutation, associated with pyrethroid resistance, and locomotor activity. Repellency bioassays were performed to assess the response of the mosquitoes to human odor by exposing them to 10% DEET applied to the skin in ethanol. Samples from the field population showed higher frequency of the kdr mutation, 21.9% homozygous and 21.9% heterozygous, greater locomotor activity and greater sensitivity to DEET than the laboratory population. These results suggest increased sensitivity to DEET in field populations and a possible interaction between insecticide exposure and sensitivity to DEET.

Silent circulation of Zika and dengue virus in Aedes aegypti (Diptera: Culicidae) during a non-epidemic year in the state of Sergipe, northeastern Brazil.

BACKGROUND: Dengue virus (DENV) and Zika virus (ZIKV) have a severe impact on human health worldwide. To understand the dynamics of these viruses in mosquito populations, it is necessary to maintain surveillance during non-epidemic years. METHODS: We aimed to assess the presence of DENV and ZIKV in Aedes aegypti females in the state of Sergipe, northeastern Brazil, during a non-epidemic year. The Ae. aegypti females collected were sectioned, and the heads and thorax were used to analyze the infection rate. Each female was first analyzed to detect Flavivirus using RT-PCR. Flavivirus-positive samples were further screened to detect ZIKV and DENV types 1, 2, 3 and 4. RESULTS: A total of 184 females were collected. ZIKV was identified in 5.4% of the sample and DENV in 7.1%, with the DENV-positive samples belonging to subtypes 2, 3 and 4. The presence of coinfected vectors was also observed. Of the four cities tested, only one was negative for all viruses. CONCLUSIONS: These results show that the maintenance of vigilance during non-epidemic years can provide data on viruses circulating before the onset of outbreaks. This can enable the planning and implementation of local control measures to prevent the appearance of new outbreaks.

Molecular characterization and phylogenetic analysis of Chikungunya virus during the 2016 outbreak in Sergipe, northeastern Brazil.

BACKGROUND: Chikungunya (CHIKV) is an arbovirus transmitted mainly by Aedes aegypti females. CHIKV has been highlighted as the pathogen with the greatest impact due to the high morbidity caused by the infection. In 2016, Brazil experienced an outbreak that affected almost 272 000 people. Here, we performed a molecular characterization and phylogenetic analysis of the CHIKV circulating in 2016 in the state of Sergipe, Brazil. METHODS: A partial region of the E1 gene of 16 CHIKV-positive samples from Sergipe State was amplified and sequenced. RESULTS: All sequences belonged to the East-Central-South-African genotype and three point mutations were verified. Two of them were silent mutations and one was a non-synonymous mutation, which changed lysine to threonine at position 211 in the E1 protein. This mutation was present in 81.2% of the sequences, as well as in other five Brazilian sequences from previous studies. This study found that CHIKV strains circulating in Sergipe during the 2016 outbreak belonged to two different haplotypes. CONCLUSIONS: The strains circulating in Sergipe are phylogenetically close to other Brazilian samples circulating in the northeast and southeast of the country, as well as viruses circulating during the same period in Haiti, indicating the rapid spread of these haplotypes.

Diversity of Mosquitoes (Diptera: Culicidae) in the Caatinga Biome, Brazil, from the Widespread to the Endemic.

Mosquito fauna in the northeast semiarid region of Brazil, Caatinga biome, are poorly known. Studies on the diversity are scarce and the few surveys available focus on local fauna. In order to understand the ecological pattern of mosquito's distribution, information available from studies from 2008 to 2015 were gathered. A partitioning framework of the beta diversity, the turnover (ßJTU) and nestedness (ßJNE) components were used to determine dissimilarity among communities. Eighty-two morphospecies were recorded and 47 of the species were not shared between the areas. The most representative genera were Aedes, Anopheles, Psorophora, Haemagogus, Coquillettidia, and Mansonia, which all include species of medical interest. The communities had high rates of variation, and the mechanism of turnover accounted for the observed diversity pattern. Despite differences in collection methods, the observed dissimilarity may be related to the broad environmental heterogeneity of the biome, the intrinsic relationships of the species with their habitats, and the environmental degradation caused by different types of anthropogenic interference. Considering the mosquito species richness and endemicity, the hypothesis that the Caatinga harbor poor biodiversity is rejected. The spatial variation observed is of particular importance and should be taken into account for the knowledge of Caatinga biodiversity.

Changes in the epidemiological profile of intestinal parasites after a school-based large-scale treatment for soil-transmitted helminths in a community in northeastern Brazil: Epidemiological profile after large-scale school-based treatment for STH.

Intestinal parasites cause a significant public health problem worldwide due to the associated morbidities, mainly in infected school-aged children (SAC). The strategy of large-scale deworming in SAC to control the transmission of soil-transmitted helminths (STH) has been advocated by the World Health Organization and was recently adopted in Brazil; however, the long-term effects of mass deworming on the larger parasitological profile have been less studied. After a five-year period of school-based large-scale treatment for STH using an annual single dose of albendazole in a community of Sergipe state, Brazil, a marked reduction in prevalence was observed (15.4%% vs.7.4% for Ascaris sp., 6.0%%  vs. 0.4% for hookworm, and 12.8%%  vs. 4.5%% for Trichuris trichiura), with the exception of Strongyloides stercoralis, which had no statistically significant change in prevalence. There was, however, an increase in the prevalence of intestinal protozoans, specifically Entamoeba histolytica/E. dispar (0.0%% vs. 36.0%), Blastocystis hominis (0.0%%  vs. 40.1%), and Giardia duodenalis (5.6%% vs. 14.5%). Although the findings showed a dramatic reduction in the prevalence of STH after four rounds of preventive chemotherapy, there was an increase in intestinal protozoan infections, indicating a change in the epidemiological profile.

Lippia gracilis essential oil in ß-cyclodextrin inclusion complexes: an environmentally safe formulation to control Aedes aegypti larvae.

BACKGROUND: One of the most efficient ways to prevent arboviruses, such as dengue fever, yellow fever, chikungunya and Zika, is by controlling their vector, the Aedes aegypti. Because this vector is becoming resistant to most larvicides used, the development of new larvicides should be considered. ß-Cyclodextrin (ß-CD) complexes have been investigated as an interesting way of enabling the use of essential oils in water as larvicides. This study comprised the development of Lippia gracilis essential oil (LGEO) and ß-CD inclusion complexes for control of Ae. aegypti. RESULTS: Thermal analysis clearly showed the formation of complexes using kneading and co-evaporation methods. Gas chromatography analysis showed that kneading without co-solvent (KW) gave the highest content (∼ 15%) of the LGEO major component. Moreover, KW showed that the complex had a 50% lethal concentration (LC50 ; 33 ppm) lower than that of pure LGEO (39 ppm); in other words, complexing LGEO with ß-CD improved the larvicidal activity. In addition, LGEO complexed with ß-CD (KW) was not harmful to non-target organisms at the concentrations needed to control Ae. aegypti larvae. CONCLUSION: The inclusion complex with LGEO was a feasible formulation, being economically viable, easy-to-apply and without impact on non-target organisms and, therefore, is a potential alternative larvicide for Ae. aegypti control. © 2018 Society of Chemical Industry.

Mosquitoes of the Caatinga. III. Larval Habitats, Frequency, and Dynamics of Immature and Adult Stages in a Dry Brazilian Forest.

Even though the seasonally dry tropical Caatinga forest is an historically neglected biome, recent studies have enhanced our knowledge of its biodiversity. We investigated larval habitats as well as the frequency and dynamics of immature and adult Culicidae in a conservation unit within the Caatinga in the Brazilian state of Sergipe. We carried out monthly surveys between July 2011 and October 2012 to count both immature (tree holes, bromeliad tanks, ponds, and rock holes and depressions) and adult individuals (Shannon traps baited with light). In total 8,021 individuals representing 32 taxa, eight of which are currently undescribed, were collected. The majority of the specimens collected came from tree holes followed by bromeliads, ponds, and rock depressions. Ponds had the highest species richness in this survey while the bromeliad fauna exhibited high endemicity. We also reveal a correlation between precipitation during the month prior to collection and the abundance of immature individuals in tree holes. Peaks in Haemagogus sp. near spegazzinii and Aedes terrens abundance were observed soon after rain, whereas Culex conservator was abundant during the rainy season in tree holes evidencing a species rotation within this habitat. Although the results of this study contribute to our knowledge regarding the distribution of mosquitoes in Brazilian semiarid region, further taxonomic studies will be required to fully understand the richness and endemism of the Neotropical Culicidae fauna.

Quiescence in Aedes aegypti: Interpopulation Differences Contribute to Population Dynamics and Vectorial Capacity.

The strategy of Aedes aegypti to prolong embryonic viability by quiescence has severe implications for geographic expansion and maintenance of mosquito populations in areas under control measures. We evaluated the effects of quiescence on biological parameters directly or indirectly associated with population dynamics and vectorial capacity in populations of this mosquito species from two Brazilian municipalities characterized as dengue, chikungunya, and Zika transmission areas. Egg viability, initial hatching time, post-embryonic development time, adult emergence rate, sexual proportion, adult size, fecundity, and fertility were analyzed using eggs stored for 10, 40, 70, 100, 130, and 160 d. Quiescence time reduced overall egg viability and post-embryonic development time in both municipalities but was more costly in Aracaju (100 d, 8 d) than in Recife (130 d, 7.5 d). Emergence rates increased in Recife when the eggs were older, but not in Aracaju. Significant deviations in sexual proportion, with male predominance, were observed in both populations. Initial hatch, fecundity, fertility, and adult size did not significantly influence egg quiescence time. These results indicate intrinsic and differential characteristics for each A. aegypti population, suggesting a differential cost of quiescence for population dynamics parameters that can indirectly affect vectorial capacity and control measures.

Mosquitoes of the Caatinga: 1. Adults stage survey and the emerge of seven news species endemic of a dry tropical forest in Brazil.

The Caatinga is the least known Brazilian biome in terms of the diversity of Culicidae. No systematic study of the diversity or ecology of the mosquitoes of this biome is available, despite the importance of vector diseases in Brazil. The present study addressed the mosquito biodiversity in the Caatinga biome by sampling adult populations. Specimens were sampled monthly from March 2013 to September 2014 in a Caatinga conservation unit located in the Brazilian semiarid zone. Mosquito collections were carried out in Shannon traps from late afternoon to early evening, and manual aspiration was used to capture diurnal species as well. A total of 4,692 mosquitoes were collected. The most dominant and constant species were all undescribed species belonging to the genera Wyeomyia and Runchomyia, which together represented 80% of the specimens. The most abundant species of epidemiological importance was Haemagogus (Con.) leucocelaenus. The abundance of mosquitoes was positively associated with the relative humidity and temperature recorded during the month preceding the collection date. In the Caatinga, the diversity of adult mosquitoes was associated with the availability (quantity and diversity) of natural larval habitats found in the different phytophysiognomies of the biome, which vary according to temperature and humidity. The number of species unknown to science reflects the levels of endemism that exist in the study area, and reinforces the need to further taxonomic investigation in the biome.

Genetic variability and spatial distribution in small geographic scale of Aedes aegypti (Diptera: Culicidae) under different climatic conditions in Northeastern Brazil.

BACKGROUND: The study of the genetic structure of Aedes aegypti is essential to understanding their population dynamics as well as for the analysis of factors responsible for their resistance and ecological adaptation. The use of molecular markers in identifying differences amongst populations of Ae. aegypti in different geographical areas as well as the temporal variation of the vector populations has contributed to the improvement of vector control strategies. The present study aims to determine the genetic variability of Ae. aegypti populations in a small geographical area (state of Sergipe, Northeastern Brazil) by means of inter-simple sequence repeat (ISSR) and single nucleotide polymorphism (SNP) molecular markers. RESULTS: ISSR markers revealed a more heterogeneous pattern of genetic diversity among the populations with an expected heterozygosity (H E) ranging from 0.261 ± 0.03 to 0.120 ± 0.032, while a similar trend was detected through SNPs across populations with an H E between 0.375 ± 0.054 and 0.269 ± 0.042. The population's genetic differentiation assessed with ISSR and SNP markers indicated a very low structuring among the populations with the highest diversity observed within the populations 72 % (ISSR) and 92 % (SNP). Clustering analysis also suggested little variation among populations: the seven populations were grouped into only three ISSR clusters and a single panmictic group based on SNP markers. The present study identified a close relationship between the populations, which probably results mainly from passive gene flow between mosquitoes from distinct geographic regions, influenced by humans commuting along roads. CONCLUSIONS: There was an intense migration of mosquitos across municipalities, leading to a potential increase in risk of arbovirus and insecticide resistance associated-alleles spreading between mosquito populations.