Bird Flu

There has been a lot of publicity recently about bird flu, especially over the past year with the outbreak that occurred in Turkey. De Faye’s chemists pharmacist Richard Lyness, gives us the low down on avian flu and the risk it may pose to humans.

WHAT IS BIRD FLU?

Avian (a general term which refers to birds) infects wild birds such as ducks and domestic birds such as chickens. There are 15 subtypes of bird flu and the strain causing this current outbreak is known as H5N1 which usually proves fatal in birds. This strain has affected poultry in several countries since 2003.

WHY SHOULD HUMANS BE CONCERNED ABOUT BIRD FLU?

The bird flu virus can occasionally jump between species and infect people who have been in close contact with infected birds. The first human case was seen in Hong Kong in 1997 and to date 146 people have caught the infection resulting in 76 deaths.

HOW IS BIRD FLU PASSED FROM BIRDS TO PEOPLE?

The virus can infect people who are in close contact with infected birds e.g. by people inhaling dried faeces that have become trampled into dust or stuck to feathers or another body part of the infected bird.

CAN BIRD FLU BE PASSED FROM PERSON TO PERSON?

At the moment it is thought that the virus can jump the species barrier (from birds to humans) but it cannot pass easily from person to person. However, there is the possibility that a bird flu virus could merge with a human flu virus to create a new virus. This new virus could then be passed between humans which may result in a large outbreak, or pandemic, of a highly contagious flu.

HOW CAN A BIRD FLU VIRUS MIX WITH A HUMAN FLU VIRUS?

There are 2 possibilities:

In humans- if a person who already has flu comes into close contact with birds who have highly contagious strain of bird flu, there is a tiny chance that the person could become infected with the bird flu virus. If this happens, the person would now be carrying both the human and the bird flu virus. The two viruses could then swap genes with each other.
In pigs- pigs are susceptible to both human and bird flu viruses. If a pig became infected with both viruses at the same time, it could act as a ‘mixing vessel’, allowing the two viruses to merge and form a new virus.

HAVE THERE BEEN CASES OF SPREAD OF BIRD FLU IN HUMANS?

There have been a few instances in Thailand and Vietnam but so far there has been no wide spread transmission between humans. The route of transmission in these cases remains unconfirmed bit is most likely to be due to very close contact with very sick birds.

WHAT ARE THE SYMPTOMS OF BIRD FLU?

Symptoms tend to be similar to other types of flu- fever, sore throat, cough- and people can also develop eye infections. More serious cases can lead to pneumonia and breathing problems.

ARE THERE ANY TREATMENTS AVAILABLE FOR BIRD FLU?

There is not currently a vaccine to protect against bird flu although several prototypes are being developed. Producing a vaccine is difficult as the virus frequently changes.

There is some evidence that antiviral drugs may help limit symptoms and reduce the chances of further spread of the virus. The UK government has stockpiled supplies of oseltamivir (Tamiflu) which can reduce the severity of ordinary flu. There is evidence to suggest that the H5N1 bird flu virus does respond to this treatment bit there have also been sporadic reports of partial resistance to Tamiflu.

CAN I STILL EAT CHICKEN?

Yes. Experts say avian flu is not a food-borne virus so eating chicken is safe and the only people thought to be at risk are those involved in the slaughter and preparation of potentially infected meat. The World Health Organisation has issued advice recommending, that to be absolutely safe, all meat should be cooked to a temperature of at least 70 degrees centigrade. Eggs should also be thoroughly cooked.

WHAT CAN BE DONE TO CONTAIN THE SPREAD OF BIRD FLU?

Millions of birds have been culled in the countries affected by the current outbreak in an attempt to remove the potential for the virus to spread through the chicken population. Both the UK and the EU have placed bans on imports of live chickens, poultry meat products and eggs from infected countries

WHAT IS THE ADVICE ABOUT TRAVELLING TO AFFECTED COUNTRIES?

At present there are no recommended restrictions on travel to any country currently experiencing outbreaks of bird flu in poultry flocks, including countries which have also reported cases in humans. However, it is recommended, that if you are travelling to an affected country you:

Avoid visiting live animal markets and poultry farms
Avoid contact with surfaces contaminated with animal faeces
Do not attempt to bring any live poultry products back to this country