Cambodia's health ministry on Monday expressed concern about the latest strain of avian influenza, urging the public to take precautions and maintain good hygiene when handling poultry.

The current strain of bird flu known as Asian H7N9, is a subgroup of the previous H5N1 strain and was first detected in China in 2013. It can infect both humans and live birds.

"H7N9 is a subtype that we may not be able to contain," said Doctor Ly Sovann, director of the health ministry's Communicable Disease Control Department, at a press conference in the capital Phnom Penh.

"We have been able to contain H5N1 so far, but H7N9 is difficult [to contain]," he said.

When the H1N1 virus affects poultry, the birds die immediately, so the disease can be prevented from spreading, Ly Sovann said, adding that the H5N1 strain is still being found in birds in Asia, Europe, and Africa.

But when H7N9 infects poultry, the virus does not kill the infected birds, and it can be passed on to humans, he said.

The number of infections caused by the newer H7N9 virus are on the rise and are difficult to treat, he said.

Since 2013, there have been more than 1,500 human infections by the H7N9 virus in China, according to a World Health Organization (WHO) report issued on June 8.

The virus has forced farmers to cull millions of chickens and other poultry in China, Japan, and South Korea to try to contain the disease over the last few years.

A few cases of the H7N9 virus that occurred in China then spread to Laos and northern Vietnam, but Cambodia has been free of the bird flu since 2014, according to the WHO.

Though no recent cases of H7N9 infections in humans have been detected in Cambodia, authorities continue to take preventive measures against the virus by operating thermal scanners at Phnom Penh International Airport, seaports, and border crossings to detect travelers with high body temperatures who may be infected, Ly Sovann said.

Teng Srey, deputy director of the Communicable Disease Control Department, said Cambodians should not eat sick chickens or those found dead because they could contract the H7N9 virus if the birds are infected, the Khmer Times reported.

"It is likely to happen because the virus is still circulating in poultry," she was quoted as saying. ""H7N9 has infected poultry in Laos as well as in Vietnam. Although it has not been transmitted to humans yet, we must remain vigilant in Cambodia because we import meat from Vietnam."

The early symptoms of both strains of avian influenza, which occur after exposure to infected poultry, include a high fever and cough that in some cases can progress to very serious illness, including severe pneumonia, acute respiratory distress, septic shock, and multi-organ failure leading to death, according to the U.S. Centers for Disease Control and Prevention.

There is currently no publicly available vaccine to protect against H7N9 virus infection.

Reported by Maly Leng for RFA's Khmer Service. Translated by Nareth Muong. Written in English by Roseanne Gerin.

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