For more than a decade, Cambodian health facilities have been supplied with ineffective anti-venoms to treat snakebites, a situation resulting from incorrect advice given by foreign venom experts to the Ministry of Health, according to a recent report by the Australian Venom Research Unit.
Between 1997 and early this year, the Ministry of Health purchased a variety of Indian-made anti-venom products for distribution to hospitals, none of which, researchers said, “are appropriate for use in treatment of snakebite envenoming caused by any of the medically important snake species that occur naturally in Cambodia.”
“The consequence of this error is that the Ministry has wasted hundreds of thousands of US dollars purchasing anti-venoms which not only lack specificity and efficacy, but have poor safety profiles and a well-documented history of high adverse reaction rates,” the report said, adding that the use of these products “should be discontinued immediately.”
The 2009 report, titled “Snakebite management in Cambodia: towards improved prevention, clinical treatment and rehabilitation,” was commissioned by the World Health Organization and forms the basis for a training course for local doctors on snake bite case management and protective measures that started on Friday.
Dr Heng Taykry, secretary of state of the Health Ministry, said he was not sure about the use of the ineffective anti-venom products in the past, but added the WHO was now helping to train medical staff in the treatment of venomous snakebite.
Dr Taykry said that most of the health risks from snakebite stem from the fact that people who get bitten seek advice from traditional doctors.
The report said there are six species of venomous snakes considered Category One by the WHO, such as the Malayan pit viper, the Indo-Chinese Russel’s viper and the Monocellate cobra; snakes in this category are highly venomous and widespread and are responsible for most of the severe and potentially fatal bites.
The venom research unit, which is connected to the University of Melbourne, also recommended that the Health Ministry start buying anti-venom products directly from manufacturers in Thailand.
Until recently the ministry was buying ineffective Indian-made anti-venoms from Cambodian wholesalers at nine to 15 times the Indian retail price of around $8 a unit, researchers found.
The usage of these ineffective anti-venom products started in 1997 when the WHO’s Western Pacific Regional Office passed on advice from the Japanese Snake Institute and Colorado State University in the US, who wrongfully assumed that “Cambodia shared a common snake fauna with India,” the report said. These inappropriate anti-venoms have dominated Health Ministry supplies ever since, according to the report.
The Ministry of Health had sought assistance from the WHO at the time, in the wake of severe flooding along the Mekong River, as it believed the floods would lead to a snakebite emergency.
Other shortcomings the study identified in the healthcare system with regard to snakebites were a lack of knowledge among medical workers to treat bites, absence of formal policy and treatment protocol, deficient data on snakebite incidence, and a lack of training resources.
Dr Khuon Engmony, deputy director of preventive medicine at the Ministry of Health, said 12 doctors had received WHO-supported training in snakebite treatment and prevention at Phnom Penh’s Calmette Hospital last week, while another 27 doctors from all provinces gathered for training in Siem Reap this week.
These doctors, she said, will go on to train medical staff in their respective hospitals and rural health clinics. “In these courses we train the emergency doctors. They have many medical skills but this course will teach them clearly how to treat patients with snakebite,” Dr Engmony said.
She added that the usage of Indian-made anti-venoms was stopped recently, but added that their use was not harmful and that they did work if a very high dosage was administered.
Traditional beliefs and the fact that health facilities are often far from people’s homes means that many Cambodians bitten by snakes rely on traditional medicine, the Australian report said, adding that patients often died in the care of traditional practitioners. It recommended basic community education to teach people in rural areas about treatment and prevention, with a particular focus needed for high-risk groups such as plantation workers.
In 2008, there were 153 reported cases of snakebite, leading to 12 deaths, Dr Engmony said, while in 2009, 150 cases have been reported so far, resulting in four deaths. She added, however, that many cases of snakebite go unreported and the actual number is likely to be many times higher.
The venom research unit found that very little reliable medical data on snakebites was available in Cambodian hospitals.
Based on estimates from medical staff in 16 health facilities in 9 provinces and in Phnom Penh, the report concluded that the annual number of treated cases in these facilities were well above 300, with the number of deaths estimated at more than 20.