Host selection and parasite infection in Aedes taeniorhynchus,endemic disease vector in the Galápagos Islands

Host selection in blood-sucking arthropods has important evolutionary and ecological implications for the transmission dynamics, distribution and host-specificity of the parasites they transmit. The black salt-marsh mosquito (Aedes taeniorhynchus Wiedemann) is distributed throughout tropical to temperate coastal zones in the Americas, and continental populations are primarily mammalphilic. It is the only indigenous mosquito in the Galápagos Islands, having colonised the archipelago around 200,000 years ago, potentially adapting its host selection, and in the process, altering the dynamics of vector mediated pathogen interactions in the archipelago. Here, we use blood–meal analysis and PCR-based parasite screening approach to determine the blood-feeding patterns of A. taeniorhynchus in the Galápagos Islands and identify potential parasite transmission with which this mosquito could be involved. Our results show that A. taeniorhynchus feeds equally on mammals and reptiles, and only one avian sample was observed in 190 successful PCR amplifications from blood meals. However, we detected endemic filarial worms and Haemoproteus parasites known to infect various Galápagos bird species in mosquito thoraces, suggesting that feeding on birds must occur at low frequency, and that A. taeniorhynchus may play a role in maintaining some avian vector-borne pathogens, although more work is needed to explore this possibility. We also isolated three different DNA sequences corresponding to hemogregarine parasites of the genus Hepatozoon from mosquito and iguana blood samples, suggesting that more than one species of Hepatozoon parasites are present in Galápagos. Phylogenetic analysis of Hepatozoon 18sRNA sequences indicates that A. taeniorhynchus may have facilitated a recent breakdown in host–species association of formerly isolated Hepatozoon spp. infecting the reptile populations in the Galápagos Islands.     

Factors Associated with Vaccination Status of Children Aged 12–48 Months in India, 2012–2013

Objectives India has more unvaccinated children than any other country despite provision of free vaccines through the government’s Universal Immunization Program. In this study, we calculated the proportion of children aged 12–48 months who were fully vaccinated, under-vaccinated, or who had not received any vaccines. Childhood, household, and sociocultural factors associated with under-vaccination and non-vaccination were evaluated. Methods Using data from India’s 4th District-level Health and Facility Survey, 2012–2013 (DLHS-4) and the 2012–2013 Annual Health Survey (AHS), we calculated the proportion of children who were non-vaccinated, under-vaccinated, or fully vaccinated with 1 dose of Bacillus Calmette–Guérin, 3 doses of oral polio vaccine, 3 doses of diphtheria–pertussis–tetanus, and 1 dose of measles-containing vaccine. The odds of full vaccination compared to non-vaccination and under-vaccination relative to various factors was assessed using a multivariable, multinomial logistic regression which accounted for survey design. Results Of 1,929,580 children aged 12–48 months, 59% were fully vaccinated, 34% were under-vaccinated, and 7% were non-vaccinated. Compared to children born in government institutions, children delivered in non-institutional settings with a skilled birth attendant present had higher odds of non-vaccination (OR 1.66) and those without a skilled attendant present had still greater odds of non-vaccination (OR 2.39) and under-vaccination (OR 1.11). Conclusions for Practice India’s vaccination rates among children aged 12–48 months remains unacceptably low. The Indian government should encourage institutional delivery or birthing with a skilled attendant to ensure women receive adequate health education through antenatal care that includes the importance of childhood vaccination.     

Bordetella pertussis infection in children with severe pneumonia,Philippines, 2012–2015

A case-comparison study was conducted based on an observational study of severe pneumonia among hospitalized children in the Philippines. The children, from 8 days to 13 years old and hospitalized with clinical diagnosis of severe or very severe pneumonia from August 2012 to February 2015, were recruited. Nasopharyngeal swabs were collected from 1152 cases and B. pertussis were detected from 34 cases by PCR. Pertussis-positive cases were more likely to have no fever, more than one week of coughing and breathing difficulty, decreased breathing sounds, and central cyanosis than pertussis- negative cases. The percentage of underweight was significantly higher in pertussis-positive cases than pertussis-negative cases. Pertussis-positive cases showed remarkably higher fatality rate than pertussis-negative cases. All of the fatal cases among pertussis-positive cases were less than 6 months old. More attention should be given to protect young infants from pertussis.     

Parent–child mealtime interactions in racially/ethnically diverse families with preschool-age children

Family meals may improve diet and weight outcomes in children; however, results from nationally representative samples suggest that these relationships vary by race/ethnicity. Observing parent–child mealtime interactions may lend insight to why racial/ethnic differences exist. In this pilot study, a multi-ethnic sample of low-income families (n = 30) with a preschool-age child was videotaped during a dinner in their home. A global coding scheme was used to assess the following: ‘Action’ (behaviors that divert attention from eating), ‘Behavior Control’ (behaviors intended to modify another person’s behavior), and ‘Communication’ (i.e., meal-oriented, interpersonal, and critical). All families spent a significant amount of time in ‘action’ oriented behaviors that diverted their attention from eating. We also observed racial/ethnic differences in communication (i.e. critical) and behavior patterns (i.e. behavior control). This study demonstrated that this approach for observing parent–child mealtime interactions in a naturalistic setting among a diverse study sample was feasible; however, future studies should address how these patterns relate to dietary intake and weight status.     

Dietary supplementation of lutein reduces colon carcinogenesis in DMH-treated rats by modulating K-ras, PKB, and β-catenin proteins

In colon cancer, disturbances have been detected in genes coding for proteins involved in cellular proliferation, such as K-ras, β-catenin, extracellular signal-regulated kinases (ERKs), and the protein kinase B (PKB). Although carotenoids such as lutein have an important role to prevent and treat some types of cancer, there are very few studies about the effect of lutein against colon cancer and its activity at the molecular level. Therefore, the aim of this study was to evaluate the chemoprotective activity of lutein against colon cancer induced by dimethylhydrazine (DMH). The results showed a significant increase in protein expression for K-ras and β-catenin in tumors of DMH-treated rats. Simultaneously, we detected changes in the phosphorylation state of ERK1/2 and PKB in DMH-treated animals. Lutein given in the diet (0.002%), before (prevention) and after (treatment) DMH administration, diminished the number of tumors by 55% and 32%, respectively. Moreover, lutein significantly decreased in tumors the expression of K-ras (25%) and β-catenin (28%) and the amount of pPKB (32%), during the prevention, and 39%, 26%, and 26% during the treatment stage, respectively. This study demonstrates the chemoprotective effect of lutein against colon cancer by modulating the proliferative activity of K-ras, PKB, and β-catenin proteins.     

Is bioelectrical impedance vector analysis of value in the elderly with malnutrition and impaired functionality?

OBJECTIVE: The calculation of body composition using bioelectrical impedance analysis is difficult in the elderly because most equations have been found to be inadequate, especially in the malnourished elderly. We therefore evaluated the use of bioelectrical impedance vector analysis in elderly nursing home residents. METHODS: One hundred twelve nursing home residents were included in the study (34 men, 78 women, age 85.1 y, age range 79.1-91.4 y). Nutritional status was determined by the Mini Nutritional Assessment (MNA), functional status was assessed by handgrip strength, knee extension strength, and Barthel's index, and bioelectrical impedance analysis was performed using Nutriguard M (Data Input, Darmstadt, Germany). RESULTS: Twenty-two nursing home residents were classified as well nourished (MNA I), 80 were considered to be at nutritional risk (MNA II), and 10 were classified as malnourished (MNA III). Handgrip strength, knee extension strength, and Barthel's index were lower in MNA II and MNA III than in MNA I. Phase angle also decreased significantly with the MNA (4.0, 3.8-4.7 degrees; 3.7, 3.3-4.3 degrees; and 2.9, 2.6-3.5 degrees). There was a significant displacement of the mean vector in MNA II and MNA III compared with MNA I. CONCLUSION: The bioelectrical impedance vector analysis resistance/reactance graph could represent a valuable tool to assess changes in body cell mass and hydration status in elderly nursing home residents.     

Vaccination with recombinant Clostridium perfringens toxoids α and β promotes elevated antepartum and passive humoral immunity in swine

Due to the increasingly restricted use of antimicrobials in animal production systems, the prevention and control of Clostridium perfringens type A- and C-induced diarrhea in piglets should be based on passive immunization via the prepartum vaccination of sows. Given the current obstacles in the production of conventional clostridial vaccines, the use of recombinant proteins has been considered to represent a promising alternative. In the present study, the neutralizing antibody response of immunized sows and their litters to a bivalent vaccine containing the C. perfringens recombinant toxoids alpha (rTA) and beta (rTB) produced in Escherichia coli was assessed. Rabbits (n = 8) and pregnant sows (n = 7) were immunized with 200 μg of each recombinant antigen using Al(OH)₃ as adjuvant. The alpha and beta antitoxin titer detected in the rabbits’ serum pool was 9.6 and 20.4 IU/mL, respectively. The mean alpha and beta antitoxin titers in the sows’ sera were 6.0 ± 0.9 IU/mL and 14.5 ± 2.2 IU/mL, and the corresponding individual coefficients of variation (CV) were 16.04% and 14.91%, respectively. The mean alpha and beta antitoxin titers in the litters’ serum pools were 4.2 ± 0.4 IU/mL and 10.9 ± 1.7 IU/mL, and the CV between litters was 9.23% and 9.85%, respectively. The results showed that the rTA and rTB proteins produced and tested in the present study induced an immune response and can be regarded as candidates for the development of a commercial vaccine against C. perfringens type A- and C-induced diarrhea in pigs.     

Urban–Rural Differentials in Overweight and Obese Individuals with Diarrhea in Bangladesh

Objective: The study aimed to determine urban and rural differences in overweight and obesity (OO) with diarrhea regarding subjects’ sociodemographic, clinical characteristics, etiology, and antimicrobial susceptibility.

Methods: Relevant information from 2000 to 2011 were extracted from the data archive of the Diarrheal Disease Surveillance System of urban Dhaka (1248, 4.5%) and rural Matlab (615, 3.4%) hospitals of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b).

Results: The proportion of OO significantly increased in both urban (3–7%; chi-square for trend p < 0.001) and rural (1–6%; p < 0.001) areas over the study period. In multivariate modeling, monthly income more than US$100 (odds ratio [OR] = 54.44, 95% confidence interval [CI], 25.37–116.82, p < 0.001), high wealth quintile (OR = 18.23, 95% CI, 8.63–38.49, p < 0.001), access to sanitary toilet (OR = 3.07. 95% CI. 1.76–5.26. p < 0.001), boiled drinking water (OR = 2.77, 95% CI, 1.09–7.05, p = 0.032), antimicrobial use before hospitalization (OR = 4.99, 95% CI, 2.85–8.74, p < 0.001), fever (OR = 0.14, 95% CI, 0.37, 0.50, p < 0.001), watery stools (OR = 5.59, 95% CI, 2.11–14.80, p < 0.001), dehydrating diarrhea (OR = 5.17, 95% CI, 2.54–10.52, p < 0.001), intravenous saline infusion after hospitalization (OR = 2.65, 95% CI, 1.28–5.49, p = 0.009), and Salmonella infection (OR = 0.20, 95% CI, 0.50–0.83, p = 0.027) remained significantly associated with urban OO individuals. At least 88% of Shigella isolates were susceptible to ciprofloxacin in both urban and rural areas; for mecillinum it was 90%. Ciprofloxacin had the least detected resistance for Vibrio cholerae (0%) and trimethoprim-sulfamethoxazole (TMP-SMX) showed the greatest resistance (Dhaka 86%; Matlab 98%). Susceptibility for Salmonella showed ampicillin (95%), chloramphenecol (100%), ciprofloxacin (95%), ceftraxone (93%), TMP-SMX (95%) at both sites.

Conclusion: Urban OO with diarrheal illnesses was significantly different from that in rural areas, including antimicrobial susceptibility.     

A simple approximation to the bias of gene–environment interactions in case–control studies with silent disease

One of the most important research areas in case–control Genome-Wide Association Studies is to determine how the effect of a genotype varies across the environment or to measure the gene–environment interaction (G × E). We consider the scenario when some of the “healthy” controls actually have the disease and when the frequency of these latent cases varies by the environmental variable of interest. In this scenario, performing logistic regression with the clinically diagnosed disease status as an outcome variable and will result in biased estimates of G × E interaction. Here, we derive a general theoretical approximation to the bias in the estimates of the G × E interaction and show, through extensive simulation, that this approximation is accurate in finite samples. Moreover, we apply this approximation to evaluate the bias in the effect estimates of the genetic variants related to mitochondrial proteins a large-scale prostate cancer study.     

Vaccination status of children aged 1–4 years in Afghanistan and associated factors, 2015

BackgroundChildhood mortality in Afghanistan fell by half between 1990 and 2015, due in part to the government’s commitment to improving pediatric immunization services. Although progress has been made, immunization coverage has nonetheless remained low with only 65% of children receiving the third dose of Diphtheria-Pertussis-Tetanus (DPT3) based on WHO estimates. This study aims to calculate the proportion of Afghan children aged 1–4 years who were fully vaccinated, under-vaccinated, or non-vaccinated with government-recommended Expanded Program on Immunization vaccines and identify predictors related to the family’s sociodemographic status and maternal autonomy.MethodsData from the 2015 Afghanistan Demographic and Health Survey was used to calculate the proportion of children who were fully vaccinated (i.e. received all recommended vaccines), under-vaccinated (i.e. received some, but not all), and non-vaccinated (i.e. did not receive any vaccines) according to WHO guidelines. A multivariable multinomial logistic regression model generated odds ratios for under-vaccination and non-vaccination versus full vaccination, and examined associations between independent factors and full vaccination status.ResultsWe found 40.6% of Afghan children age 1–4 were fully vaccinated, 42.4% under-vaccinated, and 17% non-vaccinated. Large disparities characterized immunization coverage among provinces and between urban and rural regions. Birthing in a government institution (vs. non-institutional setting), a higher number of antenatal care visits, and a visit to a health facility in the past 12 months were all associated with increased odds of full immunization. Factors related to maternal autonomy including maternal decision-making and maternal attitudes towards beating were also significantly associated with vaccination status.ConclusionApproximately 60% of children in Afghanistan are under-vaccinated or non-vaccinated, leaving millions of children unnecessarily at risk for vaccine-preventable diseases. Engagement with community and religious leaders to create programs that increase women’s autonomy and expand access to institutional delivery could lead to downstream increases in childhood vaccination coverage.     

Measles infection in persons with secondary vaccine failure,New York City, 2018–19

A large measles outbreak in New York City, which included cases among vaccinated persons and adults presumed to be immune, provided the opportunity to better understand vaccine failure and the potential impact on measles transmission. Immunoglobulin G (IgG) avidity can distinguish primary (low avidity IgG, indicating no evidence of prior immunity) versus secondary vaccine failure (high avidity IgG, indicating prior immune response and waning antibody). Measles IgG avidity was measured on samples from 62 persons: avidity was high in 53 (16 vaccinated and 37 with unknown vaccination history) and low in 9 (1 recently vaccinated and 8 with unknown vaccination history). Secondary transmission from 2 persons with high-avidity IgG results occurred. These findings illustrate that in settings of sustained measles elimination, measles infection and transmission can occur in persons with secondary vaccine failure, underscoring the need to maintain a high index of suspicion for measles during an outbreak despite prior or presumed prior vaccination.     

Children with breakthrough varicella infection requiring hospitalization in Turkey (VARICOMP Study 2008–2013)

IntroductionVaricella in previously immunized individuals, known as “breakthrough varicella”. While the majority of breakthrough cases are mild, some may be severe, requiring hospitalization in previously healthy children or children with an underlying condition.MethodsThis report, as a part of the prospective national pediatric varicella hospitalizations study (including 29 centers, represent 50% of pediatric population) in Turkey, is aimed to evaluate breakthrough varicella infection requiring hospitalization before the routine use of single-dose live varicella vaccine in national program from 2008 to 2013 (<10% of the pediatric age group received a single-dose vaccine).ResultsIn the time period, 1939 children were hospitalized due to varicella infection in Turkey; 36 children (20 boys, 16 girls, mean age 68.0 + 37.6 months, all received single dose live varicella vaccine) with breakthrough varicella infection. Breakthrough varicella infection might be severe in previously healthy children (61.1%) and children with immune-compromising conditions (38.9%). The time elapsed between vaccination and hospitalization was approximately 5 years, and neurological complications, mainly encephalitis and meningitis, were the most common reason for hospitalization in previously healthy children.ConclusionPediatric breakthrough varicella requiring hospitalization have been seen in Turkey, is mainly observed in previously healthy children at 5 years after a single-dose varicella vaccine. The varicella vaccine has been implemented as part of the National Immunization Program in Turkey in 2013 (a single dose at age 12 months). Further surveillance in the same settings could evaluate the effectiveness of national immunization with single-dose varicella vaccine at 12 months of age and potential need for second dose of vaccine.     

Araçatuba virus: a vaccinialike virus associated with infection in humans and cattle

We describe a vaccinialike virus, Araçatuba virus, associated with a cowpoxlike outbreak in a dairy herd and a related case of human infection. Diagnosis was based on virus growth characteristics, electron microscopy, and molecular biology techniques. Molecular characterization of the virus was done by using polymerase chain reaction amplification, cloning, and DNA sequencing of conserved orthopoxvirus genes such as the vaccinia growth factor (VGF), thymidine kinase (TK), and hemagglutinin. We used VGF-homologous and TK gene nucleotide sequences to construct a phylogenetic tree for comparison with other poxviruses. Gene sequences showed 99% homology with vaccinia virus genes and were clustered together with the isolated virus in the phylogenetic tree. Araçatuba virus is very similar to Cantagalo virus, showing the same signature deletion in the gene. Araçatuba virus could be a novel vaccinialike virus or could represent the spread of Cantagalo virus.     

Increasing sexually transmitted infection rates in young men having sex with men in the Netherlands, 2006–2012

Background

Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.

Methods

Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.

Results

In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.

Conclusions

MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.

     

Behavior associated with HIV and HCV infection in female prison inmates in São Paulo, Brazil

An increase has been observed in AIDS and hepatitis C cases in women, including female prison inmates. This study focused on inmates' behavioral factors associated with risk of HIV and HCV transmission in a women's detention facility in S?o Paulo, Brazil. Behavioral questionnaires were applied and HIV and HCV serology were performed. The selected measure of association was odds ratio for both the bi and multivariate logistic regression analyses. 290 inmates participated in the study. HIV and HCV prevalence rates were 13.9% and 16.2%, respectively. Statistically significant associations were observed (p < 0.05) between HIV and the following variables: partner with AIDS OR = 6.9 (2.7-35.2); injection drug users (IDU) OR = 3.3 (1.6-14.7); regular partner OR = 3.7 (1.5-8.3), and between HCV and: IDU OR = 13.7 (4.4-42.7); IDU partner OR = 4.9 (1.9-12.2); previous arrest OR = 2.8 (1.2-6.5) adjusted for: partner with AIDS, IDU, IDU partner, drug user, and previous arrest. In conclusion, parenteral risk was associated with HIV and HCV infection and sexual risk with HIV. Appropriate and continuous preventive programs are recommended in the prison.