PBL 3 CASE 1 by Nur Syazana Mohd Ghani https://padlet.com/syazanaghani25/81grpoinnz5c AVIAN INFLUENZA en-us 2017-12-04 04:20:36 UTC 2024-10-25 17:53:19 UTC hello@padlet.com The best practice strategies in controlling avian influenza virus in chicken are: https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212704815
  1. Farm management
  2. Increase Biosecurity level
  3. Reduce susceptible host by vaccination
  4. Eliminate infected farm/poultry
  5. Education campaign 
]]> 2017-12-04 04:28:21 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212704815 Eliminate affected farmNetherlands:To control the outbreak in poultry, the affected farms and other farms within a one kilometre radius were depopulated. Regulatory measures put in place included the ban on movement of live poultry, used litter and poultry dung within a 10 kilometre radius of an affected farm. syazanaghani25 https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212704945  
 Education campaign
Thailand:
Several measures were taken after the first isolation of highly pathogenic avian influenza virus in January 2004. Initially, all poultry, their products, feed, bedding, waste and manure from infected flocks were destroyed immediately by the authorities.
Meanwhile, restriction on the movement of poultry and  their products within a five kilometre radius around the infected flocks was enforced by veterinary services inspectors in collaboration with local law enforcement officers. Control checkpoints were
temporarily established in these areas. Infected premises and equipment were cleaned and disinfected.

In addition massive education campaigns have been developed and promoted in rural areas to inform populations about the need for broad participation in addressing the highly pathogenic avian influenza outbreaks in animals. Village volunteers were recruited to conduct house-to-house surveillance and early reporting of new outbreaks in animals in an effort to facilitate early detection and prompt response. These campaigns also included raising awareness on the risks associated of close contact with sick and dead poultry.
]]> 2017-12-04 04:29:39 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212704945 3) Vaccination https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212705161 2017-12-04 04:31:29 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212705161 3) Vaccination syarmimimar https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212705510 Vaccination can be a powerful tool to support eradication programs if used in conjunction with other control methods. Vaccination has been shown to increase resistance to field challenge, reduce shedding levels in vaccinated birds, and reduce transmission (9,10). All these effects of vaccination contribute to controlling AI; however, experience has shown that, to be successful in controlling and ultimately in eradicating the infection, vaccination programs must be part of a wider control strategy that includes biosecurity and monitoring the evolution of infection.


]]> 2017-12-04 04:34:50 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212705510 2) Increase biosecurity level syarmimimar https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212706282 AI viruses are introduced to domestic poultry primarily through direct or indirect contact with infected birds. Transmission may occur through movement of infected poultry; movement of contaminated equipment, fomites, or vehicles; and exposure to contaminated infectious organic material. Airborne transmission over long distances between farms has not yet been demonstrated. For these reasons, if biosecurity measures are implemented at the farm level, AI infections can be prevented.


]]> 2017-12-04 04:42:04 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212706282 Background of H5N2 dakshavm https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212776718 H5N2 is a subtype of the species Influenzavirus A (avian influenza virus or bird flu virus). The subtype infects a wide variety of birds, including chickens, ducks, turkeys, falcons, and ostriches. Affected birds usually do not appear ill, and the disease is often mild as avian influenza viral subtypes go. Some variants of the subtype are much more pathogenic than others, and outbreaks of "high-path" H5N2 result in the culling of thousands of birds in poultry farms from time to time]]> 2017-12-04 10:41:38 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212776718 Origin of the vaccine dakshavm https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212776894 The generation of H5N2 vaccine strain was based on the H5 from an Egyptian H5N1 virus and the N2 from an Egyptian H9N2 virus on a PR8 backbone. This strain had better replication rates than an H5N2 reassortant strain on an H9N2 backbone and an H5N1 reassortant on a PR8 backbone. This virus was then used to develop a killed, oil-emulsion vaccine and tested for efficacy against H5N1 and H9N2 viruses in chickens. Results showed that this vaccine was immunogenic and reduced mortality and shedding.


https://www.ncbi.nlm.nih.gov/pubmed/26620838]]> 2017-12-04 10:42:11 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212776894 NI test dakshavm https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212777259 The use of specific neuraminidase inhibition tests allowed identification of infected chickens within the vaccinated groups. These data indicate that the currently available H5 vaccines of European and North American lineages will protect chickens against the Asian H5N1 HPAI virus and reduce environmental contamination by the H5N1 HPAI virus. They will be an adjunct to biosecurity measures to reduce virus transmission.

NA positive: virus infection
NA negative: vaccinated]]> 2017-12-04 10:43:33 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212777259 Disease immunity dakshavm https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212778011 he North American and European vaccine viruses had 84 and 91% deduced amino acid sequence similarity to the HA1 segment of haemagglutinin protein of Indonesia H5N1 HPAI challenge virus, respectively. Both vaccine strains provided complete protection from clinical signs and death. The vaccines reduced the number of chickens infected and shedding virus from the respiratory and intestinal tracts at the peak of virus replication.

what do you guys think does this also mean blocking immunity? How about sterilizing immunity?]]> 2017-12-04 10:45:44 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212778011 Surveillance and response https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212797908 The participatory disease surveillance and response (PDSR) approach to highly pathogenic avian influenza (HPAI) in Indonesia has evolved significantly from the participatory disease surveillance (PDS) system developed for rinderpest eradication in Africa and Pakistan. The first phase of the PDSR project emphasized the detection and control of HPAI by separate PDS and participatory disease response teams primarily in sector 4 poultry at the household level. Lessons learned during the first phase were taken into account in the design of the second phase of the project, which has sought to further strengthen management of disease prevention and control activities by improving technical approaches, increasing active participation of key stakeholders, including local and central governments, and focusing on the village level. The ongoing evolution of the PDSR program aims to establish a sustainable community-based program within provincial and district livestock services that enhances the prevention and control of not only HPAI, but also other zoonotic and priority animal diseases.


]]> 2017-12-04 12:01:43 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212797908 Prevention and control Avian Influenza https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212798282 2017-12-04 12:03:10 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212798282 https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212799594 2017-12-04 12:08:06 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212799594 Recombinant M2E Protein based Elisa https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212823583 As the title suggests, using the M2E protein as a marker for differentiating vaccinated versus infected birds is very much possible. The concept is known as DIVA (Differentiating Infected and Vaccinated Animals).

Additional info on this serological method can be found here]]> 2017-12-04 13:20:28 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212823583 Additional Tests https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212844700 There are other additional tests that can be done in order to determine the serotype of Avian Influenza, but they aren't necessarily used for a DIVA technique. OIE mentions these techniques, kindly refer to page 9 onwards. ]]> 2017-12-04 14:01:54 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212844700 Testing Vaccines https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212845899 Vaccine effectiveness, in terms of challenging a vaccinated animal versus a naive animal can be further investigated here. ]]> 2017-12-04 14:03:48 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212845899 Efficacy of H5N2 vaccine https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212924719 H5N2 vaccinated chickens developed substantial HI and NI antibody titers directed against the virus upon vaccination with a heterologous H5N2 vaccine, and this provides a level of protection that is generally sufficient to prevent H5N1 infections.

]]> 2017-12-04 16:07:43 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/212924719 The prime correlate ofprotection against influenza virus infection is antibodies directedto the HA https://padlet.com/syazanaghani25/81grpoinnz5c/wish/213108786 file:///C:/Users/ASUS/Downloads/1-s2.0-S0264410X08009882-main.pdf]]> 2017-12-04 23:12:49 UTC https://padlet.com/syazanaghani25/81grpoinnz5c/wish/213108786 ELISA https://padlet.com/syazanaghani25/81grpoinnz5c/wish/213118689
Antibodies againt AIV were not detected by ELISA in bird vaccinated with the inactivated AI-H5 vaccine.
This chicken became positive by ELISA after challenge with HPAIV.
 
Result = inactivated confers protection against AIV, while still allowing differentiation of infected from vaccinated animals (DIVA) by ELISA test.
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