Photo by: SEBASTIAN STRANGIOCambodian microbiologists handle live H5N1 virus cultures at the Pasteur Institute's new BSL3 lab. Built with a grant from the French government, the high-containment facility has allowed local scientists to conduct in-country experiments and contribute to global efforts to combat the disease.
IN FOCUS Bird flu
Toll 254 people have died of bird flu globally since 2003, including 115 in Indonesia and 54 in Vietnam. Eight cases have been recorded in Cambodia since 2005, seven of them fatal.
Source The virus is said to originate from wild birds, but only when the virus infects domestic poultry does it become lethal. Human infection usually follows contact with the blood, nasal secretions, saliva or faeces of an infected animal.
Symptoms Fever, coughing, muscle aches, respiratory distress and pneumonia.
The Phnom Penh Post
Written by Sebastian Strangio
Wednesday, 11 February 2009
Outbreaks of avian influenza have the potential to kill thousands in Cambodia, but a coalition of health officials and international experts say they are holding the lines against the virus.
IN the midst of a string of Asian bird flu outbreaks, public health specialists say Cambodia is relatively well-placed to fight local infections, but warn that a recent scare in Kandal province is a timely reminder of the challenges that remain.
In December, 19-year-old Teng Sopheak was hospitalised after eating chicken from his village in the province's Kandal Stung district - a sickness later diagnosed as the lethal H5N1 strain of avian influenza.
As of February 2, some 254 people had died from bird flu in 12 countries, according to World Health Organisation statistics, and although the Kingdom has experienced just eight of those cases since 2005 - except for Teng Sopheak, all have been fatal - health workers fear mutations of the bird virus could lead to increasing adaptation and trigger vicious outbreaks among humans.
Nima Asgari, a public health specialist at the WHO, said that in the 18 months between Cambodia's last two bird flu cases, the country's capacity to fight the disease has grown significantly, but warned against complacency.
"Everything is relative. What you have to look at is what the situation is like now compared to three or four years ago.... The Kingdom has done an awful lot in trying to improve its response," he said.
But he added that pandemics were a feature of human history and that there was an added threat - at least potentially - from globalisation and the increased movement of people.
"One issue is: Can it happen? And the answer is yes," he said. "The other issue is: What can we do about it? And that comes about through creating capacity and response."
Asgari added that H5N1 preparedness was "a cross-government concept" involving "almost every single ministry" as well as vital linkages at the regional and global levels.
From the bottom up
But with each local hospital and poultry market a potential front line in the fight to contain the virus, successful disease surveillance relies on the awareness of grassroots medical practitioners and animal handlers, he said.
Paul Katsutani, a specialist at the US government's Centres for Disease Control and Prevention, agreed that the biggest challenge was local education, but said that the disease's relative rarity masked its potential danger, making sustained awareness challenging.
"It is still a relatively uncommon disease in this country, and awareness of a disease is really proportional to its occurrence," he said, adding that many local medical practitioners would probably misdiagnose bird flu as tuberculosis or some sort of bacterial infection.
Sok Touch, director of the Ministry of Health's Department of Communicable Disease Control, said that poultry deaths - a warning sign of bird flu infection - were "common" in Cambodia and that the Ministry of Agriculture, Forestry and Fisheries had held nationwide workshops with bird handlers, advising them how to distinguish the disease from more common avian ailments.
In the event of a suspect case of H5N1, he said, the ministry's Rapid Response Teams, specially trained in the "technicalities" of the virus, are dispatched to retrieve specimens and bring them back to Phnom Penh for confirmation and testing.
"We now have 26 teams based at the Ministry of Health and one based at each provincial town," he told the Post, adding that international partners were currently helping to extend rapid response capabilities down to the district level.
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WHEN YOU STRENGTHEN CAPACITY ... IT WOULD BE A WASTE JUST TO LIMIT IT TO TWO OR THREE DISEASES.
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While admitting that "no surveillance system is perfect", Katsutani said that the Rapid Response Teams are capable of getting to most areas in the country within six hours - an invaluable resource in the event of a serious outbreak.
And the top down
If local hospitals and pharmacists are the front line in the fight against avian influenza, Phnom Penh's Pasteur Institute is something akin to the centre of intelligence-gathering operations.
As the WHO's only designated Cambodian National Influenza Centre, the institute has tested thousands of specimens for H5N1 and is the only body with the authority to issue an official confirmation of a local outbreak, according to Philippe Buchy, head of the Institute's Virology Unit.
As well as having the ability to perform rapid diagnoses, Buchy said the Pasteur Institute also conducts research that acts as a link between national and global bird flu prevention efforts.
In March last year, the Institute opened the country's first bio-safety level 3 (BSL3) laboratory, a high-containment facility suitable for the culturing of live viruses and other hazardous tests.
Built with assistance from the French Ministry of Health, the €1 million (US$1.29 million) facility comes equipped with multiple airlocks and a ventilation system that can replace the laboratory's air with purified air 25 times an hour.
"Culturing a virus like H5N1 is extremely dangerous, and it is not possible to do it outside a BSL3 facility," said Buchy.
Although an H5N1 diagnosis can be confirmed in "around four hours" by performing a polymerase chain reaction (PCR) test with a dead specimen of the virus, Buchy said that only live culturing allows scientists to fully characterise each new strain and ensure there are no mutations in the direction of greater human adaptability.
"The advantage is that we can get greater sensitivity because before, we had to work directly on the human specimen," he said.
"This is something very specialised, which you can only do in a lab with well-trained staff [and] equipment."
Once the Institute's Cambodian lab staff make a full analysis of each strain, the samples are forwarded to the WHO, which incorporates the strain into its latest bird flu vaccines.
Aside from the potential global value of the research, Buchy said the Pasteur Institute's self-sufficiency was a crucial defence against a future pandemic.
"The day there is a pandemic, don't expect that the government will keep its borders open. That's one of our motivations: [to] try as far as possible to be totally independent from anybody else," he said.
Katsutani said the CDC was also working closely with the Health Ministry to upgrade the lab facilities of the National Institute of Public Health (NIPH), and said he hoped it would start receiving its first influenza samples for PCR analysis within "the next few months", with the eventual goal of being recognised as another National Influenza Centre by the WHO.
"We have provided training to some of the molecular technologists who will be working in this lab, and we will continue to provide training and support," he said.
"This is very important. In order to be able to do good surveillance, to respond to outbreaks of influenza, one needs to be able to do good lab testing."
But in a country where other diseases - including malaria and dengue fever - are already killing hundreds each year, Katsutani hopes that infrastructure improvements will help improve the effectiveness of disease response across the board.
"When you strengthen capacity ... it would be a waste just to limit it to two or three diseases. We hope that this strengthening of capacity and infrastructure can also help Cambodia respond to other emerging diseases that are anot influenza," he said.
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