Closer look at bird flu: Part One

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Modern chicken farm, production of white meat

A FEW weeks ago, a friend of mine purchased some roadrunners from Mbare Musika, but they were all dead within a week!
This coincided with my meeting with three gentlemen in town who reported that not only were their cattle dying, but so too were their chickens.
We no doubt all know there are fewer eggs on the local market, with various explanations and rumours doing their rounds – from export incentives to a fire that destroyed the entire chicken stock at Irvine’s Chicken industry.
However, what is bird flu?
Avian influenza, commonly called bird flu, is a viral infection of birds with avian influenza Type A viruses.
These viruses occur naturally among wild aquatic birds worldwide and have been isolated from more than 100 different species of wild birds.
Avian influenza A viruses are classified into the following two categories: low pathogenic avian influenza (LPAI) A viruses, and highly pathogenic avian influenza (HPAI) A viruses.
They are very contagious among birds and some of these viruses can infect, sicken and even kill domesticated poultry species including chickens, ducks, turkeys and animal species.
The categories LPAI and HPAI refer to molecular characteristics of a virus and the virus’ ability to cause disease and mortality in chickens in a laboratory setting.
Both HPAI and LPAI viruses can spread rapidly through poultry flocks; however, some ducks can be infected without any signs of illness.
Some wild aquatic birds can be infected with avian influenza A viruses in their intestines and respiratory tract, but do not usually get sick due to their natural immunity.
Infection of poultry with LPAI viruses may cause no disease or mild illness and may only cause mild signs such as ruffled feathers and a drop in egg production, and may go undetected.
Infection of poultry with HPAI viruses can cause severe disease with high mortality.
Both HPAI and LPAI viruses can spread rapidly through flocks of poultry.
HPAI virus infection in poultry (such as with HPAI H5 or HPAI H7 viruses) can cause disease that affects multiple internal organs with mortality up to 90 to 100 percent, often within 48 hours, such as happened to my friend’s flock.
Most of these viruses have been LPAI viruses.
The majority of the wild birds from which these viruses have been recovered are wild birds such as gulls, terns and shorebirds or waterfowl such as ducks, geese and swans, often viewed as ‘hosts’ for avian influenza A viruses.
Infected birds can spread avian influenza A viruses in their saliva, nasal secretions and faeces.
Susceptible birds become infected when they come into contact with birds infected with the virus.
Fowls can also become infected through contact with contaminated surfaces with the virus from infected birds.
Outbreaks of avian influenza A (H5N2), (H5N8) and (H5N1) have been recorded among birds.
These infect not only birds, but also infect humans and other animals.
Though most forms are restricted to birds – H5N1 is the most common form of bird flu and is deadly to birds and can easily affect humans and other animals that come in contact with a carrier.
According to the World Health Organisation (WHO), H5N1 was first discovered in humans in 1997 and has killed nearly 60 percent of those infected.
When H5 or H7 avian influenza outbreaks occur in poultry, depopulation, or culling, also known as ‘stamping out’ of infected flocks must usually be carried out.
Additionally, strict surveillance of nearby flocks that are linked to the infected area or flocks, is required and quarantine of exposed flocks with necessary culling or ‘stamping out’ if the disease is detected.
The spread of avian influenza A viruses from one ill person to another has been rarely reported and is currently not known to spread via human-to-human contact, however, because of the possibility that avian influenza A viruses could change and gain the ability to spread easily between people, some experts worry that H5N1 could possibly pose a risk of becoming a threat to humans.
Asian lineage H7N9 and HPAI Asian lineage H5N1 viruses have been responsible for most human illness worldwide to date, including most serious illnesses and highest mortality.
Therefore, monitoring for human infection and person-to-person spread is extremely important for public health.
Avian influenza A virus infection in people cannot be diagnosed by clinical signs and symptoms alone.
Laboratory testing is necessary and is typically diagnosed by collecting a swab from the upper respiratory tract (nose or throat), usually during the first few days of illness of the sick person.
I visited the Mbare open-air chicken market for myself.
On arrival, I was informed by the vendors that they were ordered to move by municipal personnel, possibly because of a bird flu alert.
Consequently, the vendors and their scrofulous chicken cages simply moved to an unsanitary space, located near well-known residential flats, themselves, unkempt and overcrowded by tenants.
Pitiably kept, cage upon cage of free-range chickens and other wild birds on the rack, care-worn and wild-eyed stared at me as if I had come to their rescue.
Vendors pushed and jostled for a sale.
I chose three of the prettiest fowls with dashing plumage of patterned brightest oranges, reds and verdant green and dappled black and cream bird I named ‘Thecla’!
The poor hapless birds died within a few days, following a strange sneezing attack.
I then came across news reports that an avian flu pandemic is affecting southern Africa, in particular neighbouring SA and Zimbabwe.
However, this came as no surprise.
Irvines lost close to an estimated 200 000 birds over a year ago and that had national ramifications.
What steps have the authorities taken to alert educate and advise poultry farmers regarding this epidemic?
What did the city fathers hope to achieve by simply moving the birds from one area to another?
How do they hope to contain the virus — if at all — under the current circumstances?
Dr Tony Monda holds a PhD in Art Theory and Philosophy and a DBA (Doctorate in Business Administration) and post-colonial heritage studies. He is a writer, lecturer, musician, art critic, practising artist and corporate image consultant. He is also a specialist art consultant, post-colonial scholar, Zimbabwean socio-economic analyst and researcher.
For views and comments: email: tonym.MONDA@gmail.com

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