By Teh Jen Lee

SO FAR the Influenza A(H1N1) virus has caused mild symptoms in patients here and there have been no deaths.

But people should remain wary because the virus can kill, as it has done so in other countries, said infectious disease experts Dr Lyn James and Dr Lim Poh Lian in a press briefing yesterday.

In Mexico it has claimed 108 lives, while in the United States, 27 people have died, according to the World Health Organisation.

Dr James, director of the Ministry of Health's communicable disease division, said nearly all deaths outside Mexico had pre-existing medical conditions.

That was the case for only half of the deaths in Mexico. The other half involved previously healthy people.

She said it's not known why the situation in Mexico differs from other countries.

As community transmission is expected to take place here at some point in the future, Singapore should be prepared that there may be fatalities, said DrLim Poh Lian, senior consultant in Tan Tock Seng Hospital's department of infectious diseases.

Dr James agreed: 'In Singapore, we have seen only mild cases. Other countries have experienced a lot more cases. The more cases you experience, you will find people with very severe disease and even death.

'It's now a pandemic, so it's a matter of time before it will hit Singapore. We're trying our best to delay it but it's not possible to totally prevent it.

'When it does eventually come into our community, we can expect to see similar pictures of what is happening elsewhere.'

Those who are at higher risk of dying from H1N1 infection include those with asthma, chronic lung disease, heart disease and suppressed immune systems.

Those who died succumbed to conditions such as severe viral pneumonia, acute respiratory distress syndrome (common in viral infections) and bacterial pneumonia as a secondary infection.

So far, so good

Dr Lim said: 'We have been fortunate so far, everyone has done well. No one has needed to be in the ICU or on the ventilator.

'From (cases in) other countries, the high-risk categories are now known. We're being vigilant to try and protect the vulnerable population.'

Of particular concern are pregnant women as there have been five known H1N1 deaths so far involving pregnant women - three occurred in the US, one in Mexico and one in the Dominican Republic.

Unlike seasonal flu, which typically hits the elderly and very young the hardest, H1N1 deaths so far have mainly involved those aged between 15 and 59.

Dr James said: 'In Singapore, most influenza deaths are of the elderly; it's almost unheard of in pregnant women.

'This is something we must be aware of if the (H1N1) virus spreads here.'

The case fatality rate (CFR) of H1N1 virus, which records the number of deaths as a proportion of the number of confirmed infections, in Mexico is 1.7 per cent - higher than the US (0.2per cent) and Canada (0.16 per cent).

This is higher than the CFR of seasonal flu here in Singapore, which is about 0.1 per cent.

Every year about 500 to 600 people here die from seasonal flu.

Those at risk should help themselves by getting flu vaccines and, if they have to travel to flu-affected countries, take precautions such as wearing a surgical mask, avoiding crowded areas and being vigilant about hygiene.

Dr Lim said: 'Even normal people can get sick. The analogy I like to use is that a normally careful driver can still get into a car accident.'

Dr James said the number of confirmed H1N1 infections depends on the testing policy of different countries.

In Singapore, even people with mild symptoms are tested because the country is in the containment phase.

In Canada, Mexico and US, doctors there may only test the more severe cases as they have a lot more cases to deal with.

Similarly, while Singapore hospitalises all confirmed H1N1 cases, only 5 to 7 per cent of confirmed cases are hospitalised in Canada, Mexico and US.

Yesterday, six new cases of H1N1 infection were confirmed here, the highest jump in a day, bringing the total to 27.

Six new cases in S'pore

SIX more people have tested positive for the H1N1 flu.

Five came from Melbourne.

Two are Australians - a boy, 6, and his sister,7. Their family came here for holidays on 11 Jun, were detected by the airport thermal scanner and sent to KKH.

Another is a Singaporean boy, 12, studying in Melbourne. He arrived on 8 Jun and developed symptoms two days later.

Another two cases involve a Singaporean woman, 39, and her son, 3. They went to Melbourne on 3 Jun and returned on 9 Jun.

The mother developed symptoms while on the plane but was not picked up by the scanner as she did not have fever then.

On 11 Jun, her son developed symptoms and the mother took him to a clinic. They were both referred to KKH.

The last case is a Singaporean male, 15, studying in the US. He returned to Singapore from San Francisco on 11 Jun.

This article was first published in The New Paper.