Department of Health Social Services & Public Safety (DHSSPS) advice on Pandemic flu.

What is pandemic flu?

It is flu that spreads rapidly to affect almost all countries and regions around the world. A flu pandemic occurs when a new strain of the influenza virus appears.

As most people will have no immunity to a new strain of the flu virus it will generally affect more people, cause more severe illness and result in much more serious disruption to society than the ‘ordinary’ flu we see each winter.

What happened in the previous pandemics?

There were three flu pandemics in the last century. ‘Spanish’ flu occurred just after the First World War and caused 50 million deaths worldwide. ‘Asian’ flu in the late 1950s and ‘Hong Kong’ flu in the late 1960s were less severe, but had serious consequences globally.

When is the next pandemic due?

No one knows for sure. Intervals between previous pandemics have varied with no recognisable pattern. A pandemic may not follow the usual seasonal pattern of ‘ordinary’ flu and could occur at any time of the year.

What is the difference between ‘ordinary’ flu and pandemic flu?

‘Ordinary’ flu is the flu that circulates most of the time and produces the winter flu we see every year. For most people ‘Ordinary flu’ whilst unpleasant is not life-threatening. The strains of virus causing this type of flu change from year to year but can be fairly reliably predicted and an appropriate vaccine can be prepared each year.

‘Pandemic flu’ is caused when a new strain of influenza virus emerges which is markedly different from recently circulating strains. These changes cannot be predicted in the same way as the changes in ‘ordinary’ flu viruses, so a vaccine specifically against the new strain cannot be developed in advance.

Will the ordinary flu jab protect me against pandemic flu?

Anyone who has been advised to have flu vaccination, should make sure they have made an appointment with a GP practice. This vaccine will not prevent someone from getting pandemic flu or avian flu, but it will protect them from the seasonal flu that will be circulating this winter.

Who will be at risk during a flu pandemic?

Everyone is potentially at risk of catching flu during a flu pandemic, as few people, if anyone, will have immunity to the virus. Certain groups or age groups may be at greater risk than others; we will not know for certain who they will be until the virus starts circulating. From past experience, around a quarter of the population is likely to develop flu, although it could be more.

Are many people likely to die?

This will depend on several factors such as how virulent the virus proves to be, which age groups are mainly affected, how soon vaccine is available and in what quantity and how effective antiviral drugs are in treating people. It is estimated that a pandemic could lead to several million deaths worldwide. With an attack rate of 25% and a fatality rate of 0.37% over 50,000 deaths could occur in the UK - about 1500 in Northern Ireland.

What contingency plans does the UK have for a flu pandemic?

The UK was one of the first countries to have a flu pandemic contingency plan in place. The 1997 plan was revised in March 2005 and again in October 2005. The plan provides the overall framework for an integrated UK-wide response, escalating as a pandemic threat increases and then as the pandemic evolves. The Northern Ireland plan seeks to reduce the negative health impact of a pandemic and the possible disruption it may cause to essential services and people’s daily lives.

What preparations are being made?

The Department is working with Boards, Trusts and others to advance contingency planning. In addition the Department is stockpiling enough treatment courses of antiviral drugs to treat those who may become ill in a pandemic.

What are antiviral drugs?

Antiviral drugs are special medicines for the treatment of certain viral infections and are likely to play an important role in treating pandemic flu. Treatment with antiviral drugs can be expected to shorten the duration of the disease, alleviate symptoms and reduce complications and serious illness.

Why don’t we make a vaccine against pandemic flu now?

Because the virus will be new and not predictable in the way that ‘ordinary’ flu viruses are. The UK Government is working with the World Health Organization, international partners, industry and others to develop a pandemic flu vaccine should the need arise. Preparatory work is being undertaken to be in the best possible position to produce vaccine against a pandemic strain as quickly as possible when the need arises, but development of a vaccine will take time (at least four to six months) and a vaccine will not be available in the early stages of a pandemic.