Outbreaks of bird flu have occurred in Asia, Africa, North America and parts of Europe Most people who have developed symptoms of bird flu have had
close contact
with sick birds. In a few cases, bird flu has passed from one person to another. Only
sporadic human cases
have been reported since 2015.
Why does avian influenza occur?
Human infections with bird flu viruses have occurred most often after unprotected contact with
infected birds
or surfaces contaminated with bird flu viruses However, some infections have been identified where direct contact with infected birds or their environment was not known to have occurred.
What is the most common form of avian influenza?
Avian Influenza A(H7) Viruses The most frequently identified A(H7) viruses associated with human infections are avian influenza A(H7N9) viruses, which were first detected in China in 2013.
What’s an avian influenza virus?
Avian influenza is a virus that causes disease in birds Poultry, pigeons and wild or migratory birds, such as ducks, can become infected with the virus. There are two forms of the virus: high pathogenicity (HPAI) and low pathogenicity (LPAI).
How did avian flu spread?
Avian influenza is mainly spread by direct contact between infected birds and healthy birds It can also be transmitted when birds come in contact with equipment or materials (including water and feed) that have been contaminated with feces or secretions from the nose or mouth of infected birds.
What elements are needed for an avian influenza pandemic to occur?
There are a number of requirements for a new pandemic to begin: i) emergence of a new viral strain to which general populations lack sufficient immunity, ii) ability of this new strain to infect humans and to cause severe disease, and, iii) capability to transmit efficiently among humans, i.e., be highly contagious.
What are the viral diseases of poultry?
- Avian Encephalomyelitis. Avian encephalomyelitis (AE) is seen in chickens, turkeys, pheasants, and quail
- Fowlpox. Fowlpox virus causes crusty and nodular lesions primarily on the unfeathered portions of the bird
- Infectious Bronchitis
- Newcastle Disease.
What type of virus is influenza?
Influenza viruses are members of the
family orthomyxoviridae
This family represents enveloped viruses the genome of which consists of
segmented negative-sense single-strand rna segments
.
Is avian influenza A RNA virus?
Avian influenza is caused by influenza A virus, which has 8 RNA segments Avian influenza is a potential and unpredictable threat to humans because of the segmented nature of the genome.
Is avian influenza A respiratory disease?
Avian influenza affects mainly birds, but several strains of avian influenza virus have caused severe respiratory illness and death in humans.
Is avian flu a coronavirus?
Abstract. Avian influenza A (H5N1) and severe acute respiratory syndrome (SARS) coronavirus are infections that cause a severe viral pneumonia leading to acute respiratory dysfunction syndrome and carry a high case-fatality rate.
Which of the following is a viral disease of poultry birds?
New castle disease is a highly contagious r zoonoic bird disease affecting many domestic and wild avian species. Its effects are most notable in domestic poultry due to their high susceptibility and the potential for severe impacts of an epidemic on the poultry industries. It is endemic to many countries.
How do disease occur in poultry?
Disease can be spread by new infectious agents entering your flock or by the spread of established infectious agents that are already in the flock Disease can be spread by: people – including through clothing, hands and footwear.
Which are the viral diseases?
- Chickenpox.
- Herpes.
- Influenza.
- AIDS.
- Mumps.
- Measles.
- Viral Hepatitis.
How many types of influenza virus are found in nature?
There are four types of influenza viruses: A, B, C and D. Human influenza A and B viruses cause seasonal epidemics of disease (known as flu season) almost every winter in the United States.
What is the influenza virus made of?
All influenza viruses consist of single-stranded RNA as opposed to dual-stranded DNA. The RNA genes of influenza viruses are made up of chains of nucleotides that are bonded together and coded by the letters A, C, G and U, which stand for adenine, cytosine, guanine, and uracil, respectively.
What is the organism that causes influenza?
Influenza is caused by infection of the respiratory tract with influenza viruses , RNA viruses of the Orthomyxovirus genus. Influenza viruses are classified into 4 types: A, B, C, and D. Only virus types A and B commonly cause illness in humans.
What is the structure of avian influenza virus?
Influenza A viruses are roughly spherical (120 nM) with glycoprotein spikes on the surface and genome consisting of eight RNA fragments that encode 10 proteins The haemagglutinin (HA), neuraminidase (NA) and matrix (M2) proteins are embedded in the envelope lipid bilayer derived from the host cell [1] (Figure 1).
Sources
https://www.mayoclinic.org/diseases-conditions/bird-flu/symptoms-causes/syc-20368455
https://cwhl.vet.cornell.edu/disease/avian-influenza
https://www.who.int/news-room/fact-sheets/detail/influenza-(avian-and-other-zoonotic)