H1N1 Update: Factors Associated with Deaths and Hospitalizations
Although patients hospitalized for 2009 H1N1 influenza infection are younger on average than those hospitalized for seasonal flu, people aged 50 and older have the highest death rates.
Researchers analyzed some 1100 cases who were hospitalized for, or had died from, pandemic influenza in California in the first 4 months of the outbreak. Among their principal findings, presented in the current JAMA:
The median age of the cases was 27.
Hospitalization rates were highest among infants under age 1 and lowest among the elderly.
Case-fatality rates — at 11% overall — were highest among those 50 and older and lowest in children under 18.
Two thirds had underlying medical conditions associated with severe disease, and over half were obese.
Secondary Bacterial Co-infections cause 29% Deaths in H1N1 Flu in USA
WASHINGTON, Oct 1 — Many people who have died of H1N1 swine flu in the United States have also had bacterial infections, health officials reported yesterday.
A study of 77 patients who died of the new pandemic H1N1 virus showed 29 per cent of them had so called bacterial co-infections, the US Centres for Disease Control and Prevention reported.
About half of these had Streptococcus pneumonia, which can be prevented with a vaccine, the CDC said. It said doctors may be missing these infections in people severely ill with flu.
The CDC has already reported that H1N1, declared a pandemic in June, has become more active as weather cools and schools reopened after summer breaks. Cases are reported in all 50 states and it is still circulating globally.
H1N1 is not any more deadly than seasonal influenza so far but it attacks a younger age group than seasonal flu does and because virtually the entire population lacks immunity, it can infect far more people at once than seasonal flu usually does.
“The findings in this report indicate that, as during previous influenza pandemics, bacterial pneumonia is contributing to deaths associated with pandemic H1N1,” the team of experts at the CDC and state health departments reported.
“Our influenza season is off to a fast start and unfortunately there will be more cases of bacterial infections in people suffering from influenza,” CDC epidemiologist Dr. Matthew Moore, who helped organise the study, added in a statement.
The report noted in previous pandemics — in 1968, 1957 and 1918 — many of the patients who died were also infected with S. pneumoniae, Haemophilus influenzae, Staphylococcus aureus and group A Streptococcus, which causes rheumatic fever and “strep throat”.
The CDC team noted that at first it did not appear that people who were seriously ill with swine flu or who died of it had secondary infections but doctors may have missed them.
“Routine clinical tests used to identify bacterial infections among patients with pneumonia do not detect many of these infections,” the CDC team reported.
Five of the patients who died, including a 9-year-old and an 11-year-old, had infections with the so-called superbug methicillin-resistant S. aureus or MRSA. None of the seven children who died had reported medical conditions that should put them at special risk of flu complications, although one was obese and one had Down syndrome.
The researchers cautioned that the patients whose cases were studied may not represent the nation as a whole. But like most of the victims of swine flu, they were young, with a median age of 31 and ranging from 2 months to 56 years.
Moore said people getting flu vaccinations should also ask about getting a pneumococcal vaccine.
Wyeth’s Prevnar is part of the routine series of immunisations that children should get, and Merck and Co. makes a vaccine against so-called pneumococcal bacteria that is available for adults, mostly those over 65. Merck also makes a Hib vaccine, although there is no vaccine to prevent group A streptococcal infections or MRSA. — Reuters
Health experts are already predicting a flood of problems that will follow the roll-out of the H1N1 vaccine. — Reuters pic
WASHINGTON, Sept 17 — One million heart attacks, 700,000 strokes and 900,000 miscarriages — US public health officials want Americans to know these will happen every single year with or without a swine flu vaccine campaign.
Yet this year, they know a significant number will be blamed on the H1N1 vaccine, which will roll out within weeks, and they are struggling to be ready.
They expect an avalanche of so-called adverse event reports, which are reports of death, illness or other health trauma that occur within two weeks after receiving treatment — in this case, the swine flu vaccine.
“We are going to be overwhelmed with potential events,” said Mike Osterholm, a public health expert at the University of Minnesota.
“Anything that happens to anybody in the period of seven to 14 days after vaccination will be reported.”
And not just to US officials. The World Health Organisation is trying to reassure a global audience that vaccines being made by 25 different companies, with various formulations, are all safe.
“If we have a safety signal in one country it could stop vaccination efforts in others,” WHO’s top flu expert Dr Keiji Fukuda told a meeting of infectious disease specialists organized by the US Institute of Medicine this week.
Flu experts themselves have little doubt the vaccine being made against H1N1 is safe. It is made using precisely the same technology as the annual seasonal flu vaccine, which is given to hundreds of millions of people every year.
But because H1N1 is new, vaccine makers have been testing it to learn what the right dose is.
SPIRIT OF ‘76
Memories linger of the 1976 swine flu debacle, when 43 million Americans were vaccinated against a virus that never spread, and newspapers filled with reports of a rare and crippling neurological disease called Guillain-Barre syndrome.
Guillain-Barre was never definitively linked with the vaccine, but many Americans have viewed immunisations with suspicion ever since.
“We have anticipated that there will be a need for enhanced surveillance for Guillain-Barre as well as other adverse events,” Dr Nancy Cox of the US Centres for Disease Control and Prevention told the meeting.
And there will be more to contend with than critical newspaper and television reports. The Internet did not exist in 1976. Nor did blogs, Facebook, Twitter or dozens of other ways for people to communicate globally and instantly.
“Information is the most globalized product of all,” Fukuda said. “The ability of blog sites to influence countries’ decision-makers and so on — coming to grips with how we deal with this is going to be a priority.”
To address this, CDC and the US Food and Drug Administration are gearing up for one of the biggest surveillance efforts ever. “We know how absolutely essential clear, transparent communications are to the public in order to have a successful vaccination campaign,” Cox said.
CDC’s weapons of choice — Facebook, Twitter, Internet RSS feeds, humorous “viral” videos posted on YouTube, iPhone apps such as the CDC News Reader. Children’s Hospital Boston has an app (short for application) called Outbreaks Near Me that allows people to track the pandemic locally. — Reuters
A doctor vaccinates a patient in a municipal vaccination centre in Nice, southeastern France. — Reuters pic
WASHINGTON, Sept 17 — The death rate from the pandemic H1N1 swine flu is likely lower than earlier estimates, an expert in infectious diseases said yesterday.
New estimates suggest that the death rate compares to a moderate year of seasonal influenza, said Dr Marc Lipsitch of Harvard University.
“It’s mildest in kids. That’s one of the really good pieces of news in this pandemic,” Lipsitch told a meeting of flu experts being held by the US Institute of Medicine.
“Barring any changes in the virus, I think we can say we are in a category 1 pandemic. This has not become clear until fairly recently.”
The Pandemic Severity Index set by the US government has five categories of pandemic, with a category 1 being comparable to a seasonal flu epidemic.
Seasonal flu has a death rate of less than 0.1 per cent — but still manages to kill 250,000 to 500,000 people globally every year.
A category 5 pandemic would compare to the 1918 flu pandemic, which had an estimated death rate of 2 per cent or more, and would kill tens of million of people.
An estimate published in the journal Eurosurveillance last month by the French Institute for Public Health Surveillance put the mortality rate far higher, at 0.4 per cent for all age groups.
Lipsitch took information from around the world on how many people had reported they had influenza-like illness, which may or may not actually be influenza; government reports of actual hospitalizations and confirmed deaths.
He came up with a range of mortality from swine flu ranging from 0.007 per cent to 0.045 per cent.
Either way, having new information about how many people were infected and did not become severely ill or die makes the pandemic look very mild, he said.
“The news is certainly better than it was in May and even better than it was at the beginning of August,” Lipsitch said.
But another expert cautioned this does not mean the pandemic will not have severe effects on people and communities because it will infect more people than seasonal flu usually does in any given year.
“This is not a severe pandemic,” said Dr. Jeffrey Duchin of Seattle & King County Public Health and the University of Washington.
“We are going to see probably twice as many people die from the flu as we do in a typical flu season. That is tens of thousands of people. And many of these people are going to be younger.”
H1N1 swine flu was declared a pandemic in June after flashing around the world in six weeks, in part because most people have virtually no immunity to it. Experts all said a true death rate would not be clear for weeks because it is impossible to test every patient and because people with mild cases may never be diagnosed.
This lack of information made the epidemics in various countries and cities look worse at first than they actually were, Lipsitch said. People sick enough to be hospitalized are almost always tested first. “Yes, there’s been hype, but I don’t think it’s been an outrageous amount of hype,” Lipsitch said.
Seasonal flu is usually far worse among the elderly, who make up 90 per cent of the deaths every year. In contrast, this flu is attacking younger adults and older children, but they are not dying of it at the same rate as the elderly do during seasonal influenza, Lipsitch said. — Reuters
World Health Organisation (WHO) said (September 4, 2009) that thus far the pandemic H1N1 flu virus continues to spread extensively in many parts of the world but has not become more serious.
The WHO said it had counted 2,837 deaths worldwide but noted that not every case was being counted any more.
WHO is closely monitoring the strain, commonly known as swine flu, and has not detected any mutation which might signal that it has become more deadly.
WHO spokesman Gregory Hartl told a news briefing, “We are continuing to see increased number of deaths because we are seeing many, many more cases.” About 250,000 cases have been laboratory-confirmed worldwide, but this is far fewer than the true number according to the WHO which has stopped requiring its 193 member states to report individual cases.
Its previous update of Aug. 28 showed at least 2,185 deaths, meaning an additional 652 deaths were reported in the past week. The virus could eventually infect 2 billion people, or a third of the world’s population, according to WHO estimates.
Every year, seasonal influenza kills between 250,000 and 500,000 people globally, it says. But H1N1 is causing a year-round flu season and may infect more people than a usual seasonal virus, potentially adding up to more deaths.
“In the best case scenario we have today, we will still have a moderate virus that is projected to cause several million deaths,” Dr. Tammam Aloudat, senior health officer at the International Federation of Red Cross and Red Crescent Societies, told a separate news briefing. “Which means that even in the best case scenario, we do have an emergency on our hands, an emergency of a scale different from what we have seen before in the modern era,” he said.
PREDOMINANT VIRUS
Tropical regions of many countries in South and Southeast Asia are reporting “increasing or sustained high levels of respiratory disease”, although Thailand has reported a declining trend, according to the WHO’s latest weekly update.
In Latin America, countries including Ecuador, Venezuela, Peru and Brazil are reporting more respiratory disease, while outbreaks seem to have peaked in Chile and Argentina, it said.
Japan is seeing an early start to its regular flu season. In Canada and the United States, influenza activity remains “low overall”, despite increases in the southeastern US region.
Drugmakers are racing to develop vaccines amid experts’ warnings that a “second wave” of the virus is approaching as weather cools in the northern hemisphere and the traditional flu season starts.
Yesterday, Novartis AG said a single dose of its vaccine might protect against the virus, raising hopes that potentially tight supplies could go further when mass immunisation starts this month.
Hartl has called the preliminary results “encouraging”, noting any vaccine that can be administered in one dose would substantially increase the number of overall doses available. — Reuters
GENEVA, Sept 4 — H1N1 flu has killed at least 2,837 people but is not causing more severe illness than previously and the virus has not mutated, the World Health Organisation (WHO) said today.
The WHO is carefully monitoring the virus to detect any mutation which might signal that it has become more deadly.
“There is no sense that the virus has mutated or changed in any sense,” WHO spokesman Gregory Hartl told a news briefing. “We are continuing to see increased number of deaths because we are seeing many, many more cases.”
About a quarter of a million cases have been laboratory-confirmed worldwide, but this is far fewer than the true number according to the United Nations agency which has stopped requiring countries to report individual cases.
A WHO weekly statement on the latest strain, commonly known as swine flu, is expected later today. The agency’s previous update of Aug. 28 showed at least 2,185 deaths. — Reuters
Thursday's meeting (28 August 2009) with the Minister of Health, Dato' Sri Liow Tiong Lai and the Director General of Health Tan Sri Mohd Ismail Merican, was certainly a high point in timely dialogue between two seemingly disparate and separate sectors of the health service for Malaysia, particularly in the context of the current outbreak of the A(H1N1) influenza.
Among the many doctors (>60) who attended were several enthusiastic representatives from the MMA, PPSMMA, FPMPAM, PCDOM, APHM, AFPM, as well as several other interested medical practitioners from the Klang Valley, and even as far away as from Penang. It underscores the importance of such a meeting to help demystify the approach to the swine flu which has taken Malaysia by storm.
More importantly, the meeting was rather civil and accommodating with both sides cautiously trying to understand some of the undercurrents of unease which has permeated the relationship, especially whenever some untoward event related to the H1N1 occurs. The most recent recriminations took place when a woman teacher died after some supposedly possible delay in her treatment, when she had come down with the flu.
The difficulty in obtaining the antiviral drug (oseltamivir) was once again highlighted, and the restrictions in its use, were exposed, although in theory, the algorithm for managing the flu patient had been disseminated. Clinical judgement regarding moderate or severe symptoms and signs are not as clearcut as many would like to have believed.
The epidemiology of the Flu thus far was given by Dato' Dr Abdul Hassan, Director of Communicable Diseases, MOH. Dr Chris Lee gave a quick but comprehensive summary of the management guidelines as agreed to by the MOH and its task force and experts.
Clarifications were sought, with the plea by most private medical practitioners to further simplify the management of referring patients with suspected more serious complications to hospital sooner. Examples of patients being given the round around when referred for further action at various hospitals were given, which demonstrated that on the ground, practical issues still dominate the actual situation about whether the individual patient gets the treatment without too much delay. Some bureaucratic hiccups still take place, which may make the patient and doctor experiences very frustrating.
There was a further plea by the FPMPAM president, that there should not be too much finger-pointing at the private sector doctors, every time something bad or untoward occurs, because this is felt to undermine the credibility and morale of private doctors, who very often are not really to blame, and where circumstances and actual issues are the bugbears which create an environment of miscommunication and confusion.
However, in the light of the wide community spread of this H1N1 flu, there was a pledge on both sides to work harder to address these problematic areas, and ensure smoother and perhaps more constructive management of very ill patients.
Because, the MOH did not have a system in place to monitor or survey the usual flu like illness, in the country, it was felt that this makes it very hard to know if this current flu outbreak was really out of the ordinary, or perhaps just a little more virulent for some. Thus, it was agreed that GPs will assist the MOH by completing daily update notifications of all ILI, to help us maintain a closer surveillance and scrutiny of the situation on the ground.
Closer collaboration with the district MOH offices was also urged, with the plea for the MOH to circulate to all neighboring doctors any current or changed protocols so that GPs can be alerted to these more timely and accurately--the district MOH offices were felt to be the best community area to disseminate these updates.
Current changes will be notified at the MOH special H1N1 wbsite, and all doctors are urged to keep themselves apprised of changes or modifications regularly.
It was further announced that a National A(H1N1) Pandemic Influenza Conference 2009 would be organised very soon on 12 September 2009 at the Renaissance Hotel KL. This will be jointly organised by the MMA, the MOH and FPMPAM.
Researchers have discovered a possible link between obesity and an increased risk of dying from H1N1. — Reuters pic
PARIS, Aug 30 — Obesity has emerged as a possible contributing factor in fatal swine flu cases, according to ground-breaking research looking at deaths caused by the pandemic in countries around the world.
The claim is made by a team from the French Institute for Public Health Surveillance, which has studied the characteristics of 574 deaths associated with the pandemic H1N1 influenza up until the middle of July. According to the team’s findings, published in medical journal Eurosurveillance, underlying disease was found in at least half of all fatal cases.
Mortality patterns were in many cases similar to those associated with normal, seasonal flu. But the team observed: “Nevertheless two risk factors are noticeable: pregnancy and obesity.”
Pregnancy is already a well-documented risk factor in seasonal influenza and in previous pandemics. The study found that 16 women — representing 10 per cent of all female deaths that were studied — were pregnant or had recently delivered at the time of their death. Half of these also had other health issues. But the conclusion that obesity may be a factor in some swine flu deaths opens up a new line of investigation for epidemiologists. Where an underlying disease was found to be present after someone had died of swine flu, in more than one in four cases the deceased had a metabolic condition — diabetes and/or obesity.
The team, which concluded further research needed to be done to establish the link between obesity, severe influenza and mortality, also found significant demographic variations among those affected by the pandemic.
“Compared to younger age groups, the elderly seem to be protected from infection to some extent, perhaps due to previous exposure to strains akin to the H1N1 virus,” the team claim.
There has been a view that fatal cases involving the pandemic have tended to occur among the young, according to the team. And they found the average age of those who have died was 37. More than half of all deaths occurred among the 20- to 49-year-old age group. Overall, 12 per cent of deaths occurred in cases aged 60 years or more.
According to the latest update from the Health Protection Agency (HPA): “In the last seven days, cases reported globally have increased by 8 per cent and the number of deaths by 21 per cent.” However, the HPA suggested flu rates in England were now coming down.
Concerns remain, however, that infection rates will start to increase again come the autumn.
The French team warns: “The pandemic… is far from over, and deaths will unfortunately continue to occur. As in previous pandemics, available data show that age groups are not equally affected.” — The Observer
PARIS - MORE than half the fatalities from swine flu have been among young adults, according to one of the first surveys to gather mortality data from across the globe for the new A(H1N1) virus.
The analysis of 574 pandemic deaths from 28 countries through mid-July, released this week, also found that being diabetic or obese significantly boosted the risk of dying.
Neither children nor the elderly are as vulnerable as initial reports indicated, found the study, published by Eurosurveillance, the monitoring arm of the European Centre for Disease Prevention and Control.
'Most deaths (51 per cent) occurred in the age group of 20-to-49 year-olds, but there is considerable variation depending on country or continent,' the researchers reported.
Only 12 per cent of those who died were 60 or older.
All of these features - high mortality among young adults and the obese, but not the very young or elderly - are sharply different than for the seasonal flu.
More than 90 per cent of deaths from seasonal flu - which claims 250,000 to 500,000 lives annually according to the WHO - are in people over 65.
By contrast, with the pandemic H1N1, 'the elderly seem to be protected from infection to some extent, perhaps due to previous exposure to similar strains,' the study conjectured.
Persons born before 1957, other studies have suggested, were almost certainly exposed to the milder seasonal A(H1N1) viruses that evolved from the terrible pandemic of 1918, which left some 40 million dead.
With the 2009 strain, 'when infection does occur, however, the percentage of deaths in elderly cases seems to be higher that in others.' One common target across both pandemic and season strains is pregnant women, according to the study, led by Philippe Barboza of the French Institute for Public Health Surveillance. __
FATALITY RATIO
On Tuesday, the European Union said pregnant women should have priority in the distribution of vaccines, along with health workers and people with underlying health problems.
The data underlying the study also suggests that about six people die for every 1,000 infections, two or three times the rate of seasonal flu, but far less than the deadly pandemic of 1918.
The researchers caution, however, that it is far too early to calculate the 'case-fatality ratio' (CFR) with much accuracy.
'Evaluating CFR during a pandemic is a hazardous exercise. Aside from the issue of whether or not a death has been caused by the influenza infection, cases tend to be detected initially among severely ill patients with a higher probability of dying,' they conclude.
This leads to an over estimation of how lethal a virus is, they note.
Swine flu first erupted in Mexico in April, and has since swept across the globe, infecting hundreds of thousands and leaving more than 1,800 dead, according to the World Health Organisation. -- AFP
The World Health Organisation (WHO) has said the swine flu virus is not affected by any variation in the temperature, the Press Trust of India (PTI) reported.
Citing cumulative report of swine flu cases and deaths from different nations around the globe, WHO said the H1N1 virus has infected people from several countries with varying temperatures.
As per a WHO report, nearly 1,800 deaths registered from across 177 countries and territories around the globe.
Dr S J Habayeb, WHO representative in India, said, "H1N1 virus has no relation to weather. Swine flu cases have been heard from countries with cold and hot temperatures."
Citing example, he said, "Swine flu cases have been equally reported from Texas, New York and California, though the temperature varies in all the three places. Texas is warmer than New York."
According to WHO, North and South America reported highest number of A/H1N1 cases, where more than 1,500 deaths have been reported.
This has been followed by European countries with over 32,000 people testing positive for the virus and more than 50 deaths reported from all over the continent.
The third most affected area is the western pacific region with over 27,000 cases already testing positive for H1N1 and 50 deaths reported from there.
It is followed by the South-East Asian region. Nearly 13,000 positive cases and 106 deaths have already been reported from different countries in this region.
Finally, the Mediterranean region has over 2,000 cases and eight deaths have been reported from there so far.
Dr Jai P Narain, Director, Communicable Diseases, WHO, said, "If cases are being reported in hot and humid climate like India, the same is also being heard about in cold country like Australia."
"All depends on the immune capacity of the people. All five continents have been affected equally," he said. - Bernama
WHAT are the current and potential problems doctors might be facing in combating the spread of the swine flu?
It would be good if every doctor kept a constant and close tab on the H1N1 pandemic, and remained fully aware of the developments and changes, which are evolving daily. Logging on to the internet regularly for more updated information would certainly help.
(Pic by Barky / sxc.hu)
Every doctor has to be more proactive and practise more responsible and cautious medical professionalism during this trying period, which is expected to go on for one to two years. Importantly, they must assiduously look out for lung complications, quickly identify high-risk profiles, and refer these patients promptly for further specialised care.
Easier access to antiviral drugs and responsible use and monitoring would help allay public fears of delayed treatment, but this should be with care. There is genuine fear that the precious antiviral drug might be used indiscriminately for prevention; this could inadvertently create the worse outcome of drug-resistant bugs.
However, in light of the very quick deterioration and death of some young patients, it might be prudent to use antiviral treatment earlier and more aggressively.
We look forward to the specific H1N1 vaccine when it does come our way, probably towards the end of the year. In the meantime, encouraging those in the front line, heart or lung patients, and frequent travellers to have the seasonal flu vaccination is a useful adjunct to help stem the usual problems from other flu types
We are facing some problems with health insurance companies. This is especially the case in private hospitals, where many insurance companies are refusing to reimburse for the treatment because it appears that pandemic illness is excluded from the contract for medical insurance. Hence, it is good that Etiqa health insurance has come forward to state publicly that the H1N1 flu is a reimbursable illness.
Is the government's current logistics capable of handling this outbreak, or a second or third wave of the flu as predicted?
It is difficult to say at this time. We certainly hope that this second or third wave will not take place. It is almost a certainty that the community spread of the A(H1N1) flu in Malaysia will escalate, and more and more Malaysians will come down with this flu.
However, the MMA wishes to reiterate that most of these infections would be quite mild and require only symptomatic treatment, bedrest and close watch at home. Only a minority (perhaps 2% to 5%) may require hospital care or more.
If these very severe complications occur in a staggered manner, then we can cope with the problem. But if a huge unprecedented outbreak of very severe complications takes place, this can easily overwhelm the system. That said, contingency plans of equipping general wards with intensive care capacities, or even field hospitals, have been made.
There are also structured plans to increase the country's intensive care bed capacity to at least twice the number available now (which is around 300 beds only). However, training sufficient staff and specialists to provide such care may require more time and expert guidance.
Should all doctors advise their patients to self-quarantine if they display symptoms?
Yes, this is the message that we have been advocating: it is best for all doctors to advise their patients to self-quarantine if they display flu-like symptoms. This is the first and most basic step in curbing the spread of the disease.
Would the MMA describe the current A(H1N1) pandemic as "out of control"?
At this juncture, the MMA does not believe that the situation is out of control and that we need any health curfew. The health minister yesterday announced that the government would only consider declaring a health curfew if the mortality rate due to influenza A(H1N1) outbreak goes above 0.4%. According to their calculations, currently, the country's mortality rate is between 0.1% and 0.4%.
Some have suggested that we shut down the country by imposing a nationwide health emergency lockdown. But this is quite futile as the disease is already in place within the community.
Microscopic view of influenza virus particles (Pic by Dr FA Murphy, Centers for Disease Control and Prevention; source: ah1n1.com)
How long should a shutdown go on for? One week, 10 days, or longer? What about the economic implications and the day-to-day running of the country and businesses? What happens when another surge appears? Do we need to have repeated cycles of national curfew?
It makes no practical sense to even consider this at this time. The actual numbers, while alarming to some, are still manageable.
So why do the growing numbers seem to imply that we are getting more and more infections, with what appears as a disproportionate number of deaths?
There is no clear or adequate answer to this. I do not believe that the Health Ministry is to blame for the forthright transparency, which it has been practising right from the outset.
There is organisational acknowledgement that our viral testing may have been less than adequate, and there have been long queues and frustrations from many worried patients, some of whom were sent home with no tests offered. Thus, there were and are many flu patients in the community who have not had confirmatory tests performed. This under-reporting would add to the lower numbers of laboratory-proven or confirmed A(H1N1) flu infections.
The World Health Organisation has estimated that for every confirmed case, there are at least another 20 patients who would have been infected. This means that most of these are not serious enough to be counted. Many would have had mild or even no symptoms. In this context, the actual numbers would have been grossly underestimated.
So it is unfair to state that the Health Ministry is manipulating the numbers to justify the growing death rate, which we have already predicted would happen simply based on the attack rate of this contagious flu.
We must inform the public that this pandemic will continue for at least another year or two, with the intensity likely to become less serious and less feared with time, unless the dreaded second wave of reassortment into a more virulent form of the H1N1 virus takes place. There is no indication that this second wave has taken place yet, even in Mexico, USA, UK or Australia.
Also, the complication rates appear to have plateaued, and most health authorities have learnt to cope with this and the expected number of deaths. The scenario in Malaysia is probably still evolving, with the peak still to come, but I would predict that the mortality rate would become less frightening as we cope with the complications better.
It is possible that many more Malaysians in the country have come into contact with this flu and are suffering very mildly from it. Most would have got better without much concern. It is those few who seem to get complications so quickly that make us afraid.
As with most communicable diseases, we will overcome this outbreak in time, but we need to be patient, vigilant and socially responsible, and work together.
THERE has been much alarm over the rising number of cases and the fatality rate of the A(H1N1) virus, and rightly so, because the A(H1N1) is infectious.
Unfortunately, 67 have already died in Malaysia. But if you were to be objective, 67 deaths, out of a possible 70,000 to 80,000 cases, amounts to a death rate of 0.08%. This is still a bit higher than the usual seasonal flu death rate of 0.04%, but surely not anywhere near panic-inducing proportions.
But while alarm and widespread panic is unnecessary, there exists the pressing need to restrategise and implement mechanisms and Standard Operating Procedures (SOP) for the prevention of secondary bacterial pneumonia.
A closer look at the deaths reveal that 80% were A(H1N1)-associated, or were incidentally found to have contracted the virus, the virus by no means causing the death.
We can call this A(H1N1)-associated death or death with incidental A(H1N1) infection. So, if the certification of death is proper, it may be that only 15 deaths were actually due to A(H1N1), giving a fatality rate of 0.02%.
The flu itself is usually a mild disease in the majority of cases. From all available clinical epidemiological evidence, the bulk of patients dying in flu pandemics are from secondary bacterial pneumonias. This has been shown to be the case in all flu epidemics and pandemics.
This is why we need to consolidate measures that are already in place. This should include a national level SOP whereby all affected patients with secondary bacterial pneumonias would be immediately triaged for intensive tertiary level care.
Indeed, we should all be vigilant, because there is an infectious disease in our midst. Good personal hygiene is crucial, now and at all times, even after this crisis. If you are not well, as always, seek medical advice.
But there is certainly no need to panic and there is no national emergency here.
There is already too much misinformation and misperception of the situation out in the lay media without having to distract the public with the hype about a national emergency.
Three experts from the World Health Organisation (WHO) are to study the rising mortality rate due to the influenza A(H1N1) in the country as the death toll hit 68 today.
Health Minister Liow Tiong Lai said Malaysia had requested the WHO to send three epidemiologists to look into the H1N1 deaths, especially why some patients developed pneumonia so fast and died in a short period.
"They would study the classification of the death due to H1N1. Some died due to co-morbid (presence of more than one disease or health condition in an individual at a given time) causes and some die from direct infection. We want them to look into the classification of death for H1N1 so that we will not over report or under report.
"This is to ensure that we can set a fair comparison as we have already adopted the WHO's guideline on this matter. The WHO will look into our death cases and observe the situation.
"The epidemiologists arrived here yesterday and have already started their work today," he told Bernama.
Health Ministry statistics showed that of the 68 deaths, 70 percent were due to co-morbid causes, 20 percent due to late treatment and 10 percent, mostly involving children, are direct infections. Study on why the virus spread so fast
Liow said the WHO experts would also study the spread of the H1N1 at the community level to determine why the virus spread so fast in this country compared with others.
According to health experts, the age group most likely to contract A(H1N1) flu is between five and 24.
However, some experts said the number of Influenza A(H1N1) deaths in Malaysia may be higher than that of its neighbours, but the fatality rate of people with confirmed H1N1 is not remarkably high.
Dr Christopher Lee, consultant physician and head of infectious diseases at the Sungai Buloh Hospital, during a recent briefing to the media, said this was especially when one considered WHO estimation that 15-20 cases went unreported for every case of confirmed A(H1N1).
Following this, it is understood that the Health Ministry has requested the WHO's help to study the death rate and come up with a fair comparison to ensure that it does not under-report or over-report cases.
Rates of swine flu are levelling off in the northern hemisphereas summer progresses. The question now is whether we’llhave a second wave this winter, and if so how bad it will be.
Two evolutionary virologists writing in JAMA are cautiouslyreassuring (JAMA 2009;302:679-80). Looking back over the 14or so pandemics since 1510, they say that pandemic flu has neverbeen able to infect the entire population at once, and althoughit tends to recur after a first wave, it eventually adopts thefamiliar seasonal flu pattern.
As for A/H1N1, they say its modest transmission efficiency andits arrival in the northern hemisphere's early summer,as well as the degree of pre-existing population immunity fromprevious flu viruses and vaccines, all give reason to hope fora more indolent pandemic course and fewer deaths than in pastpandemics. They don't think it's inevitable thatthe virus will mutate into a more virulent or contagious strain.
A second wave of A/H1N1 during the northern hemisphere'swinter would coincide with its regular bout of seasonal flu,something the southern hemisphere is experiencing at the moment.
Melissa Sweet asks what lessons we can learn from Australia(doi:10.1136/bmj.b3317), and finds contradictory views amongexperts there. Some think the final death toll of A/H1N1 willbe lower than for seasonal flu, noting that the big differencebetween now and 1918 is the availability of effective antibiotics.But others warn against being too dismissive. They are seeingrespiratory failure of an unprecedented severity in young people,sparking concerns about how well intensive care will cope.
For me the wisest voice is that of Robert Booy. "We had bothmore severe disease and a huge amount of very mild disease,and people either played it one way or the other, and in doingso they either underplayed it or overplayed it, and the truthwas somewhere in the middle." This fits with Heath Kelly'sadvice among a list of top tips for the northern hemisphere:"Be aware of the pandemic paradox: a high proportion of asymptomaticand mild cases but serious disease in the overweight and pregnantwomen."
If swine flu does come back with a vengeance, the UK may alreadyhave shot one of its bolts. Despite WHO advice to the contrary,in England the government opted for relatively indiscriminateuse of antivirals after self diagnosis.
Could the governmentreally not have provided more balanced information on the likelybenefits and harms of antivirals and been more parsimonious?
Matthew Shun-Shin and colleagues updated and expanded an earlierCochrane review on the effectiveness, safety, and tolerabilityof oseltamivir and zanamivir in seasonal influenza in children(doi:10.1136/bmj.b3172), information that must have been availableto ministers when they were making their plans.
The evidencesuggests that these two agents are of limited efficacy in childrenand are associated with a significant risk of side effects,mainly vomiting. Coupled with the risk of resistance and thefinancial cost of widespread use, these findings have led tocalls to cut back the use of antivirals in mild flu and flu-likeillness.
These calls are hard to ignore. Indeed, Hugh Pennington, emeritusprofessor of bacteriology at the University of Aberdeen, hastold the media that Tamiflu may be useless by the autumn becauseof current indiscriminate use (http://tinyurl.com/qnsm4s).
Accordingto news reports, ministers thought it would be publicly unacceptableto withhold antiviral drugs, even after it became clear thatswine flu was generally a mild illness. Yet we know it'spossible to educate patients and the public about the need toavoid unnecessary use of drugs, as last week's BMJ showed(BMJ 2009;339:b2885).
"..Most cases described during the three pandemics of the 20th century and during seasonal influenza involve transient illness not requiring hospitalisation. Most deaths are described in the very young or the elderly or those with underlying disease. The 1918-1919 pandemic, however, was characterised by a high mortality rate in healthy young adults and an estimated CFR of 2-3% [5]. Even with a low CFR, seasonal influenza epidemics cause significant morbidity and mortality with an estimated three to five million cases of severe illness and about 250,000 to 500,000 deaths worldwide [6].
To date, the CFR attributable to the current H1N1 pandemic has been estimated at around 0.4%, based on surveillance data from Mexico and mathematical modelling [7]. This CFR is higher than that of average seasonal influenza but remains of the same order of magnitude. Whether this will change before the expected epidemic peak in the northern hemisphere in the autumn is unknown.
Evaluating CFR during a pandemic is a hazardous exercise. Aside from the issue of whether or not a death has been caused by the influenza infection, cases tend to be detected initially among severely ill patients with a higher probability of dying. This leads to an overestimation of the computed CFR at the beginning of an outbreak. The computed CFR subsequently evolves as the case reporting strategy is adapted to the situation. When the situation no longer requires exhaustive reporting of cases, the computed CFR will inevitably increase and grossly overestimate the true CFR..."
I searched the WHO and CDC websites, but couldn't find A(H1N1) statistics by country. Wikipedia has compiled the figures below, from the European Centre for Disease Prevention and Control website (daily updates, as of Aug 19, 2009) and Pan American Health Organization website, and in some cases from national websites:
1) these figures cannot be used to asess the virulence of the virus circulating in the reporting country (case fatality rate, A(H1N1) deaths divided by laboratory-confirmed cases), since the pandemic has reached the stage where lab confimration of cases would overwhelm testing capacity, and most countries are now reporting only lab confirmed fatalities, i.e. the CFR is inflated to varying degrees in different countries).
2) among Malaysia's 68 reported fatalities (lab confirmed), up to 11 cases remain ambiguous as to A(H1N1) causality, although they were virus positive. perhaps our legislators (and the media) could request clarification from the relevant authorities
3) were there unregistered migrant workers among the Malaysian fatalities? if so, was treatment delayed because they were hesitant to identify themselves to health agencies or healthcare providers?
4) since the case fatality rate is not useful at this point for tracking virulence, surveillance has now shifted to unusual clustering, changes in transmission patterns, in patient profile, in natural history of the disease, etc which might suggest an evolutionary shift. Prof Adeeba's observations of rapid decline in cases with pneumonia complications deserve close attention.
Semi-logarithmic plot of laboratory-confirmed A(H1N1) influenza cases in 2009 according to WHO reports.[102]
‡Qualitative indicators as defined by WHO[103]. Parameter values:
Geographic spread
Trend
Intensity
Impact on health care services
W(idespread)
*** (very high)
sev(ere)
R(egional)
+ (Increasing)
** (high)
L(ocal)
= (Unchanged)
* (low - moderate)
mod(erate)
N(o activity)
- (Decreasing)
(low)
low
‡‡Many countries are not recommending laboratory tests for all suspect cases. As far as known, the affected numbers have been put in brackets. Comparisons in time or between these countries should not be made. The number of confirmed cases is lower than the total number of cases,[104] and may grossly underestimate the true infection rate.[105]
********************* CHAN Chee Khoon, ScD Professor & Convenor Health & Social Policy Research Cluster Women's Development Research Centre (KANITA) Universiti Sains Malaysia 11800 Penang, Malaysia tel : + 60 4 6533437 fax : + 60 4 6566379 mobile: + 60 (0)17 4808317 email : ckchan50@yahoo.com
Health experts are already predicting a flood of problems that will follow the roll-out of the H1N1 vaccine. — Reuters pic
A doctor vaccinates a patient in a municipal vaccination centre in Nice, southeastern France. — Reuters pic
GENEVA, Sept 4 — H1N1 flu has killed at least 2,837 people but is not causing more severe illness than previously and the virus has not mutated, the World Health Organisation (WHO) said today.
