scholarly journals Avian influenza transmission risk along live poultry trading networks in Bangladesh

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Natalie Moyen ◽  
Md. Ahasanul Hoque ◽  
Rashed Mahmud ◽  
Mahmudul Hasan ◽  
Sudipta Sarkar ◽  
...  

AbstractLive animal markets are known hotspots of zoonotic disease emergence. To mitigate those risks, we need to understand how networks shaped by trading practices influence disease spread. Yet, those practices are rarely recorded in high-risk settings. Through a large cross-sectional study, we assessed the potential impact of live poultry trading networks’ structures on avian influenza transmission dynamics in Bangladesh. Networks promoted mixing between chickens sourced from different farming systems and geographical locations, fostering co-circulation of viral strains of diverse origins in markets. Viral transmission models suggested that the observed rise in viral prevalence from farms to markets was unlikely explained by intra-market transmission alone, but substantially influenced by transmission occurring in upstream network nodes. Disease control interventions should therefore alter the entire network structures. However, as networks differed between chicken types and city supplied, standardised interventions are unlikely to be effective, and should be tailored to local structural characteristics.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Isha Berry ◽  
Mahbubur Rahman ◽  
Meerjady Sabrina Flora ◽  
Amy L. Greer ◽  
Shaun K. Morris ◽  
...  

AbstractAvian influenza is endemic in Bangladesh, where greater than 90% of poultry are marketed through live poultry markets (LPMs). We conducted a population-based cross-sectional mobile telephone survey in urban Dhaka, Bangladesh to investigate the frequency and patterns of human exposure to live poultry in LPMs and at home. Among 1047 urban residents surveyed, 74.2% (95% CI 70.9–77.2) reported exposure to live poultry in the past year, with the majority of exposure occurring on a weekly basis. While visiting LPMs was less common amongst females (40.3%, 95% CI 35.0–45.8) than males (58.9%, 95% CI 54.0–63.5), females reported greater poultry exposure through food preparation, including defeathering (13.2%, 95% CI 9.5–17.9) and eviscerating (14.8%, 95% CI 11.2–19.4) (p < 0.001). A large proportion of the urban population is frequently exposed to live poultry in a setting where avian influenza viruses are endemic in LPMs. There is thus not only ample opportunity for spillover of avian influenza infections into humans in Dhaka, Bangladesh, but also greater potential for viral reassortment which could generate novel strains with pandemic potential.


Author(s):  
Jeffery D. Sullivan ◽  
John Y. Takekawa ◽  
Kyle A. Spragens ◽  
Scott H. Newman ◽  
Xiangming Xiao ◽  
...  

2013 ◽  
Vol 1 ◽  
Author(s):  
Diann J. Prosser ◽  
Laura L. Hungerford ◽  
R. Michael Erwin ◽  
Mary Ann Ottinger ◽  
John Y. Takekawa ◽  
...  

TAPPI Journal ◽  
2013 ◽  
Vol 12 (3) ◽  
pp. 17-23 ◽  
Author(s):  
WANHEE IM ◽  
HAK LAE LEE ◽  
HYE JUNG YOUN ◽  
DONGIL SEO

Preflocculation of filler particles before their addition to pulp stock provides the most viable and practical solution to increase filler content while minimizing strength loss. The characteristics of filler flocs, such as floc size and structure, have a strong influence on preflocculation efficiency. The influence of flocculant systems on the structural characteristics of filler flocs was examined using a mass fractal analysis method. Mass fractal dimensions of filler flocs under high shear conditions were obtained using light diffraction spectroscopy for three different flocculants. A single polymer (C-PAM), a dual cationic polymer (p-DADMAC/C-PAM) and a C-PAM/micropolymer system were used as flocculants, and their effects on handsheet properties were investigated. The C-PAM/micropolymer system gave the greatest improvement in tensile index. The mass fractal analysis showed that this can be attributed to the formation of highly dense and spherical flocs by this flocculant. A cross-sectional analysis of the handsheets showed that filler flocs with more uniform size were formed when a C-PAM/micropolymer was used. The results suggest that a better understanding of the characteristics of preflocculated fillers and their influence on the properties of paper can be gained based on a fractal analysis.


2021 ◽  
Vol 13 (9) ◽  
pp. 1724
Author(s):  
Vojislav Mitić ◽  
Cristina Serpa ◽  
Ivana Ilić ◽  
Markus Mohr ◽  
Hans-Jörg Fecht

Materials science is highly significant in space program investigation, energy production and others. Therefore, designing, improving and predicting advanced material properties is a crucial necessity. The high temperature creep and corrosion resistance of Ni-based superalloys makes them important materials for turbine blades in aircraft engines and land-based power plants. The investment casting process of turbine blades is costly and time consuming, which makes process simulations a necessity. These simulations require fundamental models for the microstructure formation. In this paper, we present advanced analytical techniques in describing the microstructures obtained experimentally and analyzed on different sample’s cross-sectional images. The samples have been processed on board the International Space Station using the MSL-EML device based on electromagnetic levitation principles. We applied several aspects of fractal analysis and obtained important results regarding fractals and Hausdorff dimensions related to the surface and structural characteristics of CMSX-10 samples. Using scanning electron microscopy (SEM), Zeiss LEO 1550, we analyzed the microstructure of samples solidified in space and successfully performed the fractal reconstruction of the sample’s morphology. We extended the fractal analysis on the microscopic images based on samples solidified on earth and established new frontiers on the advanced structures prediction.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Divine Ekwem ◽  
Thomas A. Morrison ◽  
Richard Reeve ◽  
Jessica Enright ◽  
Joram Buza ◽  
...  

AbstractIn Africa, livestock are important to local and national economies, but their productivity is constrained by infectious diseases. Comprehensive information on livestock movements and contacts is required to devise appropriate disease control strategies; yet, understanding contact risk in systems where herds mix extensively, and where different pathogens can be transmitted at different spatial and temporal scales, remains a major challenge. We deployed Global Positioning System collars on cattle in 52 herds in a traditional agropastoral system in western Serengeti, Tanzania, to understand fine-scale movements and between-herd contacts, and to identify locations of greatest interaction between herds. We examined contact across spatiotemporal scales relevant to different disease transmission scenarios. Daily cattle movements increased with herd size and rainfall. Generally, contact between herds was greatest away from households, during periods with low rainfall and in locations close to dipping points. We demonstrate how movements and contacts affect the risk of disease spread. For example, transmission risk is relatively sensitive to the survival time of different pathogens in the environment, and less sensitive to transmission distance, at least over the range of the spatiotemporal definitions of contacts that we explored. We identify times and locations of greatest disease transmission potential and that could be targeted through tailored control strategies.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S501-S502
Author(s):  
Humberto R Jimenez ◽  
Naana Boachie ◽  
Sangwon Park ◽  
Jin Suh

Abstract Background As people with HIV (PWH) have experienced reductions in antiretroviral pill burden, there has been an increase in medications to manage non-AIDS-related co-morbidities. Previous studies have linked virologic failure to an increased pill burden. This study assessed whether polypharmacy and other variables affect success of HIV management in our population. Methods A retrospective, cross-sectional analysis of PWH receiving care at a Ryan White-funded clinic in New Jersey was performed. Eligible patients were ≥18 years old, had ≥2 visits in 2019 and were receiving antiretroviral therapy (ART). The primary endpoints were to determine the effect polypharmacy (defined as 5 or more non-ART pills per day) on virologic response rates (HIV RNA &lt; 200 copies/mL). Secondary endpoints accounted for the impact of age, gender, race/ethnicity, HIV transmission risk factor, and AIDS diagnosis on virologic response. A descriptive analysis of comorbidities and medication classes was also completed. Logistic regression, chi square and student’s t test were used for statistical analysis. Results 964 patients were included in the analysis, with 355 (37%) meeting the criteria for polypharmacy. Most patients were male (60%) and the mean age was 49 years of age. The racial/ethnic breakdown was 46% Hispanic, 45% Black and 8% White. Polypharmacy was associated with higher rates of virologic success compared to those with a lower pill burden: 94% vs 86% had an HIV RNA &lt; 200 copies/mL (P=0.0003), respectively. ART pill burden was statistically, but not clinically higher among those with polypharmacy (1.34 vs 1.45, P=0.025). Virologic response was found to be higher among Hispanics and Whites in comparison to Black patients (OR 2.2, CI 1.4-3.5 and 3.0, CI 1.1-8.2). Patients with an AIDS diagnosis were less likely to achieve virologic response (OR 0.64, CI 0.42-0.99). Conclusion Patients with polypharmacy were more likely to achieve virologic success than paitents with a low pill burden in our population. Disclosures Humberto R. Jimenez, PharmD, BCPS, AAHIVP, Gilead (Speaker’s Bureau)


2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Julia Rose Dahm ◽  
Jordana Burdon Bailey ◽  
Robert F. Kelly ◽  
Patrick Chikungwa ◽  
Julius Chulu ◽  
...  

AbstractGoats are critical in mixed smallholder agricultural systems in lower and middle-income countries, while fleas are important human and animal health concerns around the world. Convenience sampling was used to describe and consider risk factors for flea infestations of peri-urban goats, with the aim of informing the iterative development of animal husbandry and management based control strategies. Seven hundred and ninety-two goats were examined in 228 households across 10 peri-urban communities surrounding Blantyre in southern Malawi. The prevalence of Ctenocephalides felis fleas was 18.3, 37.1 and 100% at the levels of individual goats, households and communities, respectively, highlighting a neglected human and animal health concern. Constant introduction of new livestock coupled to a lack of biosecurity within communities, the ubiquitous presence of dog and cat hosts for C. felis, the frequency and thoroughness of cleaning overnight goat accommodation, and goat age less than 12 months old were identified as risk factors for flea infestation. This focal cross-sectional study highlights the significance of fleas in peri-urban communities and uncovers trends and commonalities that are needed to inform sustainable disease management. The majority of the peri-urban goat keepers were female, had resided in the same community throughout their whole life and had primary level education. Advice on the planned management of fleas in livestock needs to be tailored towards this demographic group. This approach affords an opportunity to promote public health measures to address household flea infestations and zoonotic disease spread.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 691
Author(s):  
Dae-Sung Yoo ◽  
Byungchul Chun ◽  
Kyung-Duk Min ◽  
Jun-Sik Lim ◽  
Oun-Kyoung Moon ◽  
...  

Highly pathogenic avian influenza (HPAI) virus is one of the most virulent and infectious pathogens of poultry. As a response to HPAI epidemics, veterinary authorities implement preemptive depopulation as a controlling strategy. However, mass culling within a uniform radius of the infection site can result in unnecessary depopulation. Therefore, it is useful to quantify the transmission distance from infected premises (IPs) before determining the optimal area for preemptive depopulation. Accordingly, we analyzed the transmission risk within spatiotemporal clusters of IPs using transmission kernel estimates derived from phylogenetic clustering information on 311 HPAI H5N6 IPs identified during the 2016–2017 epidemic, Republic of Korea. Subsequently, we explored the impact of varying the culling radius on the local transmission of HPAI given the transmission risk estimates. The domestic duck farm density was positively associated with higher transmissibility. Ring culling over a radius of 3 km may be effective for areas with high dense duck holdings, but this approach does not appear to significantly reduce the risk for local transmission in areas with chicken farms. This study provides the first estimation of the local transmission dynamics of HPAI in the Republic of Korea as well as insight into determining an effective ring culling radius.


Sign in / Sign up

Export Citation Format

Share Document