Introduction

Bird flu (also known as avian influenza) is a viral infection that primarily affects birds but can sometimes infect humans. There are multiple strains of the virus that can be transmitted. In recent years, certain strains (H5N1, H7N9, H5N6 and H5N8) have posed a threat to public health. In particular, H5N1 has been implicated as the most harmful to poultry and humans, resulting in a high mortality rate across both species.¹ 

Knowing which groups are more at risk of contracting the disease can help to control future outbreaks.

Transmission of bird flu to humans

The primary method of transmission involves contact with infected birds, regardless of whether they are dead or alive. Three types of exposure can cause an infection:

• Touching contaminated droppings or bedding
• Droplets which come into contact with the eyes or nasal cavity
• Airborne particles from infected chicken coops or slaughterhouses²

Though rare, it is possible for bird flu to be spread from humans to other humans through close contact – this is the case with the H5N1 strain.³ It is also important to know that you cannot catch bird flu from eating fully cooked eggs or poultry. 

Symptoms of bird flu

The onset of bird flu tends to occur rapidly and can manifest 3-5 days post-infection with:

• Fever (high temperature) 
• Shivers
• Muscle aches and headaches
• Coughing
• Shortness of breath
• Diarrhoea
• Nausea
• Stomach pains
• Bleeding nose and gums
• Pink eye (conjunctivitis): red, swollen and itchy eyes

If you suspect a bird flu infection, it is important to seek medical advice from a healthcare professional. In some cases, bird flu can progress into more severe conditions, such as acute respiratory distress syndrome (ARDS) and pneumonia. 

Because antibiotics only work in treating bacterial infections, using the correct antiviral medication is essential.

The NHS 111 helpline can be contacted online at 111.nhs.uk if you think you have contracted bird flu within the past 10 days. They can evaluate your symptoms over the phone and decide whether any further tests are necessary.

Bird flu is uncommon but, if you have the disease, self-isolation will be encouraged in order to protect others from contracting it. 

High-risk groups for contracting bird flu

Poultry workers and farmers

People who work on farms with infected poultry have a higher risk of infection due to increased exposure to birds through handling, slaughtering and defeathering.⁴

Workers in live bird markets

Unsanitary conditions in live bird markets can raise the risk of coming into contact with the virus. Poor ventilation and hygiene practices can promote the survival of the virus in the air and on surfaces. 

Veterinarians and animal handlers

During the diagnosis or treatment of infected birds, protective gear (like gloves) should be used in order to avoid the risk of contamination and infection.

Consumers in regions with bird flu outbreaks

There is a small risk that bird flu can be spread through the consumption of undercooked poultry and eggs. People who handle contaminated meat can be infected through contact or droplets on unclean surfaces.⁵

Travellers to affected areas

People who visit places with ongoing outbreaks face the risk of exposure through markets, farms or infected environments. Though bird flu affects people globally, endemic regions with high populations of wild birds can be a source of disease.⁶

Individuals with compromised immune systems

Those with pre-existing health conditions or suppressed immune systems are more vulnerable to infection. It is thought that the elderly may have some immunity from previous flu encounters, however, this might not be enough to fight off the disease as viruses can mutate quickly.⁷ 

Geographic and environmental factors

The environment has been shown to influence the spread of bird flu:⁸ 

• Rural areas, near poultry farms, can harbour a higher risk of exposure to infected birds
• Regions where H5N1 bird flu outbreaks are more common, such as southeast Asia and parts of Africa, are at a higher risk of disease transmission⁹
• Seasonal migration can spread the virus across different regions¹⁰

Understanding the factors that contribute to bird flu infections globally allows us to get a better idea of how we can protect ourselves and avoid contamination.

Preventive measures for high-risk groups

The UK Government has set guidelines on what to do in designated bird flu control zones. There are extra precautions that must be exercised for poultry keepers, such as:

• Fencing free-range birds to reduce the risk of contact between wild birds
• Separating ducks, geese and chickens
• Keeping enclosures free of faeces, feathers and carcasses
• Cleaning regularly
• Using effective pest control
• Netting bodies of water
• Maintaining records of poultry and eggs¹¹

People who work with poultry are encouraged to:

• Take seasonal flu vaccines
• Wear the correct personal protective equipment (PPE)
• Wash all wounds and cover them with a waterproof dressing
• Maintain good hygiene practices, like disinfecting surfaces and handwashing¹²

Outside of poultry workers, people are generally not at risk of contracting bird flu provided all poultry is adequately prepared for eating. A food thermometer can be used to check if meat is fully cooked.

Summary

The people at highest risk of contracting bird flu are poultry workers and people who sell birds at markets. This is because they are directly in contact with birds that may harbour the virus. To lower the risk of infection, these groups are encouraged to promote good hygiene in the workplace.

By encouraging awareness of bird flu and its preventive measures, such as vaccination and food hygiene, we can reduce the risk of avian to human transmission. This is beneficial as it will discourage new viral strains forming.

If you are concerned about bird flu in poultry in the UK, there are multiple lines you can call:

• 03000 200 301 (England)
• 03003 038 268 (Wales)
• APHA Field Services (Scotland)