The news cameras and accompanying journalists were out in force once again last week to cover a swine-flu story, after it emerged that a female student at a primary school in Roxboro, Co Roscommon, was the latest person to contract the virus.

Speaking to the media, school principal Michael Cleary said he had first been informed about the case on Wednesday, and that it was hoped the spread of the virus could be contained.

But following a meeting with parents at the school the following afternoon, it was agreed that each of the girl's fellow first- and second-class pupils should receive antiviral medication as a precautionary measure.

This meant some 28 pupils who had only got their summer holidays on Tuesday had to return to the school two days later to be administered the drugs.

As an insight into the continuing potential for swine flu to cause concern within the wider community, the Roxboro case is instructive.

By yesterday, there were 63 confirmed cases of swine flu in Ireland, representing a continuous increase over the past few months.

As the events of last week indicate, the swine-flu virus remains a potentially serious public health threat here, and one which has by no means gone away.

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Swine flu was big news a few months ago, when it frequently led the main news bulletins and generated acres of coverage in print.

Since then, however, media interest in the topic has waned significantly, due in no small part to the fact that the flu itself has proven to be relatively mild .

Similarly, the number of deaths attributed to the virus in Mexico was also revised downwards, after dozens of test samples came back negative for swine flu last May.

As a result, many people could have been forgiven for wondering what all the fuss was about.

Yet World Health Organisation (WHO) figures show that the H1N1 strain has in fact continued to spread widely since it first emerged in Mexico and the US last April, a development which prompted the WHO last month to declare its first flu pandemic since 1968.

It did this by raising its pandemic flu alert to six on a six-point scale.

According to the WHO, there were 77,201 cases of swine flu around the world by the middle of last week, a figure that has increased further in the few days since then.

By far the largest number of cases – more than 27,700 – have occurred in the USA, followed by neighbouring Mexico (8,680 cases), where the flu was first detected in April.

Both the US and Mexico have also breached the 100 mark when it comes to deaths from swine flu, an analysis of the statistics shows. They are to date the only two countries to have reached this macabre milestone.

By comparison, all of the 51 Irish cases confirmed so far have responded fully to treatment. There have been no deaths in Ireland from the virus. The vast majority of people with H1N1 here contracted it after travelling abroad.

The current rate of infection ranks us next to countries such as Belgium (47 cases) and Cyprus (48 cases) on the WHO scale, and indicates we are still a long way off our UK counterparts.

But the number of confirmed cases of swine flu worldwide is likely to be a serious underestimate of the actual figure for infections.

Just last week, for example, Dr Anne Schuchat of the US's Centre for Disease Control and Prevention told reporters that around a million people there had contracted swine flu, reflecting the fact that many sufferers may have opted to treat themselves rather than seek medical help.

Worryingly for an island country like Ireland, the UK comes fourth (after Canada) on the WHO's list of countries, and has the largest number of confirmed cases in Europe. As of 1 July, it had 6,538 such cases and three deaths.

Of even more potential significance for Ireland is the announcement by the British health secretary, Andy Burnham, late last week that swine flu can no longer be contained there, due to the sheer number of people who now have the virus.

As a result, the UK government's response has shifted from containing the spread of the virus to focusing instead on the treatment of those affected.

"Cases are doubling every week and on this trend we could see over 100,000 cases per day by the end of August," Burnham added ominously.

While not unexpected, the decision prompted our own chief medical officer, Dr Tony Holohan, to comment on Friday that it is now "much more likely that people with unknown and undiagnosed illness will come into this country and will act as a source of further infection for here".

Moreover, he added that it may not be long until we too move from simple containment to treating those affected, with some "worst-case" predictions suggesting that as many as 100,000 people a week here could eventually require medical assistance.

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Dr Patricia Johnson is principal investigator with DCU's viral immunology group, and an expert in the area.

She said the main risk with swine flu is not necessarily the infection itself, but rather the complications that can arise when a patient has it.

"What we're worried about with a flu is people with underlying medical conditions, for example a lung problem, who may be particularly vulnerable," she said.

What should not be underestimated is the potential threat from a new strain of a virus such as swine flu.

It is precisely because it is so new that it has to be taken so seriously, as unlike the common flu, we do not have a historical immunity built up, Johnson explains.

So how well prepared are we for a major swine-flu outbreak here – and what might its likely impact be?

Unsurprisingly, the HSE is keen to stress the extent of planning which the authorities here are undertaking in advance of the autumn/winter flu season, including regular meetings between various experts in the area.

It has also bought additional supplies of the two main drugs for treating swine flu – Relenza and Tamiflu – and says it now has sufficient stocks to cover 54% of the entire population.

The executive has estimated that the medical bill for the swine-flu pandemic will be in the region of €85m, including €80m for the purchase of any potential vaccine.

Swine-flu sufferers will typically be treated at home, with a view to easing the pressure on hospitals and other facilities, a spokeswoman said.

"If required, flu clinics would be set up, mostly in HSE and public buildings, and in some areas community or sports halls may be used," she added. "The flu clinics will be staffed by doctors, nurses, other healthcare professionals and administrative staff."

The effectiveness of our response to a widespread flu pandemic here is dependent upon the virus remaining relatively mild, and patients infected with the virus continuing to respond to treatment.

Dr Johnson pointed out that we have been expecting a worldwide pandemic for a number of years now.

"The problem is if a virus fails to respond to treatment," she explained. "With most human influenza it is the complications of infection that are the most serious concern. A viral infection makes people often more susceptible to bacterial infection, causing pneumonia, for example. If this in turn becomes antibiotic resistant, then it is a major concern."

Friday's revelation that a third case of swine flu showed resistance to Tamiflu will have caused some alarm among health experts.

Dr Kevin Kelleher, head of health protection with the HSE, has previously estimated that up to 50% of the Irish population could be affected by swine flu.

He said that there was some hope of a lull in the number of cases both here and in the UK over the summer months, before the traditional flu season kicks in during the autumn.

Yet rates of infection in the UK, as outlined by Burnham last week, are beginning to suggest otherwise.

Authorities worldwide are also monitoring countries in the southern hemisphere, such as Australia and New Zealand, to see how great an impact swine flu is having there, as this is currently their winter flu season, Kelleher noted.

Interestingly, he added that, if and when a vaccine for the virus becomes available, perhaps as early as next September, the current pandemic plan allows for vaccination "up to and including the whole population".

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In this context, arguably the best-case scenario for Ireland is that the virus remains relatively mild, even if rates of infection here eventually mirror those in the UK.

As a result, the biggest problem posed by swine flu could be simply the additional pressure which so many infected patients, or indeed a mass vaccination programme, might place on an already overburdened health service.

Factor into this the impact of increased sick days on the economic life of the country, should as much as half of the population become ill, and there appears little doubt that swine flu will leave its mark here.

The alternative – a more aggressive strain of the virus which does not respond to treatment and which infects a widespread number of people – would be an altogether more worrying scenario with a potentially enormous impact on our population.

As our own autumn/winter flu season approaches, in truth only time will tell how the virus will develop, and what its true impact here will be.

What is clear however is that when it comes to swine flu, the clock is already ticking.