|13 December 2005
|Subscribe for free by E-mail or
From an article by Tim Clark, SciDev.net
When people think of bird flu in Asia, Cambodia rarely springs to mind. It is usually either the massive culling of birds in China or new outbreaks in Indonesia or Vietnam that grab the headlines. Yet the H5N1 bird flu virus is widespread in Cambodia's poultry and wild bird populations alike. And with the country's limited health care capacity, inadequate surveillance and poor public health awareness, any investigation into bird flu here is a journey into the unknown.
Unlike previous virus scares in Asia, bird flu is a predominantly rural problem. If H5N1 mutates, as many experts predict it will, an outbreak could occur far from healthcare centres.
It is no coincidence that all of Cambodia's human cases of bird flu to date were in Kampot, a province near the Vietnamese border: it is the Vietnamese health care system that is finding them.
In January this year, Cambodia's first human bird flu fatality, Tit Sokhan, died in Vietnam after seeking medical treatment there.
She sought medical help in Cambodia at first, but the doctor was unable to identify her illness. Later, health workers advised her to perform a traditional ceremony to appease the spirits.
This points to one of the main problems with identifying a bird flu outbreak — rural people are not aware of the virus.
Many villages are used to seeing birds suffer from seasonally high mortality rates. Often, entire populations of chickens are simultaneously wiped out in a village every year.
"The farmers we encountered earlier this year say they accept that chickens die this time of year, and they have always been safe to eat. They ask why there is a problem now," says Megge Miller, an epidemiologist for the World Health Organization.
"We are not asking people to do something simple. We are asking them, in the face of their poverty, not to eat chickens that have died," she says.
"In that respect, it is going to take a long time to really change that behaviour, particularly if chicken is the sole source of protein for the family, or an important source of income," she told SciDev.Net, "It is money they cannot afford to waste."
Photo credit: Gemma Griffiths and Tim Clark
Live and dead chickens at a poultry stall in Phnom Penh
But education is only part of the solution. Cambodia lacks drugs and health care, and has a poor infrastructure, severely limiting its ability to contain an outbreak. The country desperately needs more funds to combat H5N1, and donors are starting to realise the extent of the problem.
The United States recently agreed to give Cambodia nearly US$2 million to fight a potential human flu pandemic. The measures include training rapid response teams, developing Cambodia's capacity to safely and accurately identify bird flu, and creating a national stockpile of medicines.
Ly Sovann, deputy director of Cambodia's Centre for Disease Control, reported that the country's Ministry of Health has just over 100 treatment courses of Tamiflu (oseltamivir) available, as little as one course for each province.
He believes that at least 20 courses are needed in each province to be able to adequately deal with an outbreak, and that even then it will depend on the speed at which an outbreak can be identified.
"We do not know whether we will pick it up early enough to have only a family cluster, or if the system will pick it up too late when the virus has spread to village level," says Sovann. "We have shown with malaria, SARS, and TB that we have experience in combating dangerous diseases. What we need is the support."
Back at the riverfront, work is at hand to prepare for the annual water festival. The celebration marks the end of the rains and will see up to a million people travelling to the capital from the provinces. No one knows how many poultry or wild birds will be brought with them.
"If we can separate different species of poultry from each other, stop them living beside humans, stop humans moving them and stop them mixing with wild birds on rice paddies, then we can solve the problem," says Martin Gilbert of the US-based Wildlife Conservation Society, which is helping assess the extent of H5N1 in wild bird flocks. "We need to break the chain of transmission."
As always, and in Cambodia particularly, this is easier said than done.
Photo credit: Gemma Griffiths and Tim Clark
Duck and ducklings in Pursat, Cambodia
From an article by Paula Leighton, SciDev.net
Insects whose bite can transmit a deadly parasite to people could be eradicated from six South American nations within five years, said scientists recently.
By 2010, Argentina, Brazil, Bolivia, Chile, Paraguay and Uruguay should all be free of the 'assassin bugs', which transmit the parasite that causes Chagas disease, they said.
Photo credit: Marcelo de Campos Pereira
The bite of the assassin bug brings Chagas disease to millions in Latin America.
Chagas disease affects 13 million people in Latin America. Each year, about 21,000 of them die, usually from heart failure caused by the chronic form of the disease.
Scientists from the region reported significant reductions in its impact at a meeting to discuss advances against the disease, held in Santiago, Chile on 6-8 October. The reduction is due in part, they said, to international initiatives launched in the 1990s and coordinated by the Pan American Health Organization and intergovernmental committees.
Techniques included spraying pesticides and making homes less appealing to assassin bugs by replacing mud walls and palm roofs with plastered walls and zinc roofs.
Myriam Lorca of the Chilean Chagas Disease Surveillance Programme says assassin bugs were so abundant in Chile in the 1980s that people used shovels to remove them from their houses. Today, she says, only 300 specimens are caught each year.
In 1999, the WHO said that Chagas disease was no longer being transmitted in Chile by either assassin bugs or by blood transfusions. Uruguay was certified free of transmission two years earlier, and Brazil is likely to be certified free by 2006, says Lorca.
But for the WHO to consider a country totally free of assassin bugs, none must have been found for three years. Lorca says the six 'southern cone' countries should achieve this by 2010, followed shortly by Andean countries and some years later by those in Central America.
A new weapon expected to play a role in this fight was unveiled at the meeting. British and Paraguayan scientists have developed a way to eliminate assassin bugs by luring them to a trap with chemicals the insects use to attract mates.
"This strategy has never been used before, as it would only be useful in areas where the number of assassin bugs has already been greatly reduced," Lorca said. "We plan to start distributing the traps in Chile by November."
From an article on BBC Online
Photo credit: LSU Agricultural Center
Golden rice (right) and white rice (left)
The WHO estimates that vitamin A deficiency annually blinds 500,000 children, mostly in developing countries. A new, genetically modified, 'golden rice' contains beta-carotene, which the body converts to vitamin A, potentially preventing blindness.
|How is Human News different?
|Contact Human News