scholarly journals Identification of High-Risk Areas for the Spread of Highly Pathogenic Avian Influenza in Central Luzon, Philippines

2020 ◽  
Vol 7 (3) ◽  
pp. 107
Author(s):  
Roderick Salvador ◽  
Neil Tanquilut ◽  
Kannika Na Lampang ◽  
Warangkhana Chaisowwong ◽  
Dirk Pfeiffer ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Highly Pathogenic Avian Influenza ◽  
Early Stage ◽  
Disease Outbreaks ◽  
The Philippines ◽  
Infectious Period ◽  
Reproductive Number ◽  
Highly Pathogenic ◽  
Outbreak Management ◽  
Pathogenic Avian Influenza

Highly pathogenic avian influenza virus (HPAIV) is a major problem in the poultry industry. It is highly contagious and is associated with a high mortality rate. The Philippines experienced an outbreak of avian influenza (AI) in 2017. As there is always a risk of re-emergence, efforts to manage disease outbreaks should be optimal. Linked to this is the need for an effective surveillance procedure to capture disease outbreaks at their early stage. Risk-based surveillance is the most effective and economical approach to outbreak management. This study evaluated the potential of commercial poultry farms in Central Luzon to transmit HPAI by calculating their respective reproductive ratios (R0). The reproductive number for each farm is based on the spatial kernel and the infectious period. A risk map has been created based on the calculated R0. There were 882 (76.63%) farms with R0 < 1. Farms with R0 ≥ 1 were all located in Pampanga Province. These farms were concentrated in the towns of San Luis (n = 12) and Candaba (n = 257). This study demonstrates the utility of mapping farm-level R0 estimates for informing HPAI risk management activities.

Estimation of the basic reproductive number (R0) for epidemic, highly pathogenic avian influenza subtype H5N1 spread

2008 ◽  
Vol 137 (2) ◽  
pp. 219-226 ◽  
Author(s):  
M. P. WARD ◽  
D. MAFTEI ◽  
C. APOSTU ◽  
A. SURU
Keyword(s):  
Avian Influenza ◽  
Highly Pathogenic Avian Influenza ◽  
Control Strategies ◽  
Basic Reproductive Number ◽  
Infectious Period ◽  
Reproductive Number ◽  
Highly Pathogenic ◽  
Pathogenic Avian Influenza ◽  
True Basic ◽  
Road Distance

SUMMARYThree different methods were used for estimating the basic reproductive number (R0) from data on 110 outbreaks of highly pathogenic avian influenza (HPAI) subtype H5N1 that occurred in village poultry in Romania, 12 May to 6 June 2006. We assumed a village-level infectious period of 7 days. The methods applied were GIS-based identification of nearest infectious neighbour (based on either Euclidean or road distance), the method of epidemic doubling time, and a susceptible–infectious (SI) modelling approach. In general, the estimated basic reproductive numbers were consistent: 2·14, 1·95, 2·68 and 2·21, respectively. Although the true basic reproductive number in this epidemic is unknown, results suggest that the use of a range of methods might be useful for characterizing epidemics of infectious diseases. Once the basic reproductive number has been estimated, better control strategies and targeted surveillance programmes can be designed.

scholarly journals Outbreak of highly pathogenic avian influenza in Ghana, 2015: degree of losses and outcomes of time-course outbreak management

2020 ◽  
Vol 148 ◽  
Author(s):  
W. Tasiame ◽  
S. Johnson ◽  
V. Burimuah ◽  
E. Akyereko ◽  
P. El-Duah ◽  
...  
Keyword(s):  
Public Health ◽  
Retrospective Study ◽  
Avian Influenza ◽  
Time Course ◽  
Highly Pathogenic Avian Influenza ◽  
Highly Pathogenic ◽  
Outbreak Management ◽  
Pathogenic Avian Influenza ◽  
Laboratory Confirmation ◽  
Greater Accra Region

Abstract This retrospective study highlights the degree of losses and time-course through which the 2015 highly pathogenic avian influenza (HPAI) outbreaks in Ghana were managed. A total of 102 760 birds from 35 farms across five regions in Ghana included in this study were affected. Out of this, 89.3% was from the Greater Accra region. Majority of the birds were culled (94.2%). Adult layers were most affected and destroyed (64.0%), followed by broilers (13.7%). Event initiation to reporting averaged 7.7 ± 1.3 days (range: 1–30 days). Laboratory confirmation to depopulation of birds averaged 2.2 ± 0.5 (0–15) days while depopulation to disinfection took 2.2 ± 0.7 (0–20) days. Overall, some farms took as long as 30 days to report the outbreak to the authorities, 15 days from confirmation to depopulation and 20 days from depopulation to disinfection. On average, outbreak management lasted 12.3 (2–43) days from event initiation to depopulation. The study reveals a significant number of avian losses and delays in HPAI reporting and management by the authorities in Ghana during the 2015 outbreak. This poses a high risk of spread to other farms and a threat to public health. Awareness creation for poultry farmers is necessary for early reporting, while further study is required to set thresholds for the management of such outbreaks by veterinary departments.

scholarly journals First detection of highly pathogenic avian influenza virus in Norway

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Knut Madslien ◽  
Torfinn Moldal ◽  
Britt Gjerset ◽  
Sveinn Gudmundsson ◽  
Arne Follestad ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Influenza A ◽  
Highly Pathogenic Avian Influenza ◽  
Wild Birds ◽  
Zoonotic Potential ◽  
Active Monitoring ◽  
Main Hypothesis ◽  
Highly Pathogenic ◽  
Pathogenic Avian Influenza ◽  
Poultry Farms

Abstract Background Several outbreaks of highly pathogenic avian influenza (HPAI) caused by influenza A virus of subtype H5N8 have been reported in wild birds and poultry in Europe during autumn 2020. Norway is one of the few countries in Europe that had not previously detected HPAI virus, despite widespread active monitoring of both domestic and wild birds since 2005. Results We report detection of HPAI virus subtype H5N8 in a wild pink-footed goose (Anser brachyrhynchus), and several other geese, ducks and a gull, from south-western Norway in November and December 2020. Despite previous reports of low pathogenic avian influenza (LPAI), this constitutes the first detections of HPAI in Norway. Conclusions The mode of introduction is unclear, but a northward migration of infected geese or gulls from Denmark or the Netherlands during the autumn of 2020 is currently our main hypothesis for the introduction of HPAI to Norway. The presence of HPAI in wild birds constitutes a new, and ongoing, threat to the Norwegian poultry industry, and compliance with the improved biosecurity measures on poultry farms should therefore be ensured. [MK1]Finally, although HPAI of subtype H5N8 has been reported to have very low zoonotic potential, this is a reminder that HPAI with greater zoonotic potential in wild birds may pose a threat in the future. [MK1]Updated with a sentence emphasizing the risk HPAI pose to poultry farms, both in the Abstract and in the Conclusion-section in main text, as suggested by Reviewer 1 (#7).

scholarly journals Differential Diagnosis for Highly Pathogenic Avian Influenza Virus Using Nanoparticles Expressing Chemiluminescence

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1274
Author(s):  
Jihee Kim ◽  
Jae-Yeon Park ◽  
Jihoon Ryu ◽  
Hyun-Jin Shin ◽  
Jung-Eun Park
Keyword(s):  
Avian Influenza ◽  
Fluorescent Protein ◽  
Highly Pathogenic Avian Influenza ◽  
Systemic Disease ◽  
Renilla Luciferase ◽  
Highly Pathogenic ◽  
Pathogenic Avian Influenza ◽  
Pathogenic Avian Influenza Virus ◽  
Green Fluorescent ◽  
Transmembrane Serine Protease

Highly pathogenic avian influenza (HPAI) virus is a causative agent of systemic disease in poultry, characterized by high mortality. Rapid diagnosis is crucial for the control of HPAI. In this study, we aimed to develop a differential diagnostic method that can distinguish HPAI from low pathogenic avian influenza (LPAI) viruses using dual split proteins (DSPs). DSPs are chimeras of an enzymatic split, Renilla luciferase (RL), and a non-enzymatic split green fluorescent protein (GFP). Nanoparticles expressing DSPs, sialic acid, and/or transmembrane serine protease 2 (TMPRSS2) were generated, and RL activity was determined in the presence of HPAI or LPAI pseudotyped viruses. The RL activity of nanoparticles containing both DSPs was approximately 2 × 106 RLU, indicating that DSPs can be successfully incorporated into nanoparticles. The RL activity of nanoparticles containing half of the DSPs was around 5 × 101 RLU. When nanoparticles containing half of the DSPs were incubated with HPAI pseudotyped viruses at low pH, RL activity was increased up to 1 × 103 RLU. However, LPAI pseudotyped viruses produced RL activity only in the presence of proteases (trypsin or TMPRSS2), and the average RL activity was around 7 × 102 RLU. We confirmed that nanoparticle fusion assay also diagnoses authentic viruses with specificity of 100% and sensitivity of 91.67%. The data indicated that the developed method distinguished HPAI and LPAI, and suggested that the diagnosis using DSPs could be used for the development of differential diagnostic kits for HPAI after further optimization.

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