Epidemiology and molecular characterization of avian influenza virus in backyard poultry of Chattogram, Bangladesh

Dutta, Pronesh; Islam, Ariful; Sayeed, Md. Abu; Rahman, Md. Ashiqur; Abdullah, Md. Sadeque; Saha, Otun; Rahman, Mohammed Ziaur; Klaassen, Marcel; Hoque, Md. Ahasanul; Hassan, Mohammad Mahmudul

doi:10.1016/j.meegid.2022.105377

Cited by 14 publications

(11 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the flock level, H9N2 AIV prevalence around Chattogram has been estimated at around 0.7% and 1.9% for backyard and broiler chickens, respectively. Another cross-sectional study of household chickens performed in the same area found a household-level prevalence of H9N2 AIV of 3.2% 45 .…”

Section: Discussionmentioning

confidence: 89%

Modelling the transmission dynamics of H9N2 avian influenza viruses in a live bird market

Pinotti,

Kohnle,

Lourenço

et al. 2024

Nat Commun

Self Cite

View full text Add to dashboard Cite

H9N2 avian influenza viruses (AIVs) are a major concern for the poultry sector and human health in countries where this subtype is endemic. By fitting a model simulating H9N2 AIV transmission to data from a field experiment, we characterise the epidemiology of the virus in a live bird market in Bangladesh. Many supplied birds arrive already exposed to H9N2 AIVs, resulting in many broiler chickens entering the market as infected, and many indigenous backyard chickens entering with pre-existing immunity. Most susceptible chickens become infected within one day spent at the market, owing to high levels of viral transmission within market and short latent periods, as brief as 5.3 hours. Although H9N2 AIV transmission can be substantially reduced under moderate levels of cleaning and disinfection, effective risk mitigation also requires a range of additional interventions targeting markets and other nodes along the poultry production and distribution network.

show abstract

Section: Discussionmentioning

confidence: 89%

Modelling the transmission dynamics of H9N2 avian influenza viruses in a live bird market

Pinotti,

Kohnle,

Lourenço

et al. 2024

Nat Commun

Self Cite

View full text Add to dashboard Cite

show abstract

“…23 The prevalence of AIVs in chickens present in farms and rural households (T0) was higher than previously described. 16,24 For broilers, all AIV-positive chickens originated from a single farm, whereas the particularly high proportion of positive backyard chickens (14.1%) may have resulted from selection bias. Refusal rate was high and the willingness of rural households to sell chickens may have been associated with ongoing or recent disease outbreaks in the village or their own flock.…”

Section: Discussionmentioning

confidence: 99%

Amplification of avian influenza viruses along poultry marketing chains in Bangladesh: a controlled field experiment

Kohnle,

Das,

Uddin

et al. 2023

Preprint

Self Cite

View full text Add to dashboard Cite

The prevalence of avian influenza viruses (AIVs) is commonly found to increase dramatically from farms to live bird markets (LBMs). Viral transmission dynamics along marketing chains is, however, poorly understood. To address this gap, we implemented a field experiment altering chicken supply to an LBM in Chattogram, Bangladesh. Chickens traded along altered (intervention) and conventional (control) marketing chains were tested for AIVs. Upon arrival at the LBM, the odds of detecting AIVs did not differ between control and intervention groups. However, 12 hours later, intervention group odds were lower, particularly for broiler chickens, indicating that viral shedding in LBM resulted partly from infections during transport and trade. Curtailing AIV prevalence in LBMs requires mitigating risk in marketing chain nodes preceding chickens’ delivery at LBMs.Article Summary LineThe high prevalence of avian influenza viruses in marketed chickens cannot be solely attributed to viral transmission within live bird markets but is also influenced by infections occurring prior to the chickens’ supply to these markets.

show abstract

“…Nomadic duck farming is a traditional approach to duck production where the ducks are kept in a free-range habitat and are allowed to roam and feed in various regions ( 40 ). In the backyard farming system, household ducks are kept overnight near or within the farmer’s house and travel only over a short distance for scavenging ( 27 ), and in the commercial farming system, ducks are kept in total confinement ( 41 ). Considering the duck farming patterns, we conducted a cross-sectional study and purposive sampling to find out AIV, H5, and H9 subtype prevalence as well as risk factors among ducks in different production systems from 2019 to 2021 in Bangladesh.…”

Section: Methodsmentioning

confidence: 99%

“…The AIV RNA prevalence in domestic ducks in parts of Bangladesh has been previously documented as 0.9–89% ( 23–25 ), whereas the dominant AIV subtypes were H5 and H9 in ducks ( 26 ). Furthermore, since the first detection of HPAI H5N1 viruses, various clades, including 2.2.2, 2.3.2, 2.3.4.2 ( 27 , 28 ), 2.3.2.1a ( 29 , 30 ), and 2.3.4.4 ( 31 ) clade of H5N6, have been identified in Bangladesh. Besides, the novel reassortant H5N1 clade 2.3.2.1a has already been isolated from the LBMs in Bangladesh, having a close relatedness to the virus isolated from birds sampled in one of the four regions of this country ( 32 ).…”

Section: Introductionmentioning

confidence: 99%

Epidemiology and phylodynamics of multiple clades of H5N1 circulating in domestic duck farms in different production systems in Bangladesh

Islam

Hossain

Amin

et al. 2023

Front. Public Health

Self Cite

View full text Add to dashboard Cite

Waterfowl are considered to be natural reservoirs of the avian influenza virus (AIV). However, the dynamics of transmission and evolutionary patterns of AIV and its subtypes within duck farms in Bangladesh remain poorly documented. Hence, a cross-sectional study was conducted in nine districts of Bangladesh between 2019 and 2021, to determine the prevalence of AIV and its subtypes H5 and H9, as well as to identify risk factors and the phylodynamics of H5N1 clades circulating in domestic duck farms. The oropharyngeal and cloacal swab samples were tested for the AIV Matrix gene (M-gene) followed by H5, H7, and H9 subtypes using rRT-PCR. The exploratory analysis was performed to estimate AIV and its subtype prevalence in different production systems, and multivariable logistic regression model was used to identify the risk factors that influence AIV infection in ducks. Bayesian phylogenetic analysis was conducted to generate a maximum clade credibility (MCC) tree and the maximum likelihood method to determine the phylogenetic relationships of the H5N1 viruses isolated from ducks. AIV was detected in 40% (95% CI: 33.0–48.1) of the duck farms. The prevalence of AIV was highest in nomadic ducks (39.8%; 95% CI: 32.9–47.1), followed by commercial ducks (24.6%; 95% CI: 14.5–37.3) and backyard ducks (14.4%; 95% CI: 10.5–19.2). The H5 prevalence was also highest in nomadic ducks (19.4%; 95% CI: 14.0–25.7). The multivariable logistic regression model revealed that ducks from nomadic farms (AOR: 2.4; 95% CI: 1.45–3.93), juvenile (AOR: 2.2; 95% CI: 1.37–3.61), and sick ducks (AOR: 11.59; 95% CI: 4.82–32.44) had a higher risk of AIV. Similarly, the likelihood of H5 detection was higher in sick ducks (AOR: 40.8; 95% CI: 16.3–115.3). Bayesian phylogenetic analysis revealed that H5N1 viruses in ducks belong to two distinct clades, 2.3.2.1a, and 2.3.4.4b. The clade 2.3.2.1a (reassorted) has been evolving silently since 2015 and forming at least nine subgroups based on >90% posterior probability. Notably, clade 2.3.4.4b was introduced in ducks in Bangladesh by the end of the year 2020, which was genetically similar to viruses detected in wild birds in Japan, China, and Africa, indicating migration-associated transmission of an emerging panzootic clade. We recommend continuing AIV surveillance in the duck production system and preventing the intermingling of domestic ducks with migratory waterfowl in wetlands.

show abstract

Epidemiology and molecular characterization of avian influenza virus in backyard poultry of Chattogram, Bangladesh

Cited by 14 publications

References 64 publications

Modelling the transmission dynamics of H9N2 avian influenza viruses in a live bird market

Modelling the transmission dynamics of H9N2 avian influenza viruses in a live bird market

Amplification of avian influenza viruses along poultry marketing chains in Bangladesh: a controlled field experiment

Epidemiology and phylodynamics of multiple clades of H5N1 circulating in domestic duck farms in different production systems in Bangladesh

Contact Info

Product

Resources

About