Infectivology Xagena

Xagena Mappa
Xagena Newsletter

The Ministry of Health in Indonesia confirmed another fatal human case of H5N1 avian influenza. The patient, a 27-year-old woman from Jakarta, developed symptoms on September 17, was hospitalized on September 19 and died on September 26. Initial investigation has revealed that the woman had direct contact with diseased and dying chickens in her household shortly before the onset of illness.

Human cases of avian influenza A(H5N1) have been reported in Vietnam, Thailand, Cambodia, and Indonesia.

The spread in humans has occurred in three distinct periods or waves of activity, since late-December 2003, when human cases were first reported.

Since mid-December 2003, several Asian countries have reported avian influenza A(H5N1) outbreaks in poultry; the disease has also been reported in wild birds and pigs.

According to the World Organization for Animal Health and based on criteria established in the Terrestrial Animal Health Code ( 2005 ), H5N1 infection in birds continues to persist in Cambodia, China, Indonesia, Thailand, Vietnam, and Laos.
Outbreaks in birds have also recently been confirmed in the previously unaffected countries of Russia and Kazakhstan, and Mongolia.

Avian influenza A ( H5N1 ) is a contagious viral infection that is thought to affect all species of birds; although rare, infection in humans can occur.
The first documented infection of humans with the avian influenza A/H5N1 virus occurred in Hong Kong in 1997, when the strain caused severe respiratory disease in 18 humans, six of whom died. The infection in humans coincided with an epidemic of H5N1 in Hong Kong's domestic poultry population.

Investigation into human cases of H5N1 suggests that direct contact with infected poultry has been the primary, if not the exclusive, means of infection; although, in a small number of instances a link to direct contact with infected poultry was not identifiable. In a few cases it would appear that human-to-human transmission may have occurred. However, such cases involved extended close personal contact with an infected individual ( i.e. providing bedside care for an infected relative ) and no further transmission occurred.

At this time, there is no vaccine that protects against the avian influenza A/H5N1 virus. While the current seasonal flu shot does not protect against the H5N1 virus, immunization with it may be of benefit for travellers to geographic regions where human cases of H5N1 are being reported. Individuals who are immunized with the seasonal influenza vaccine are less likely to contract seasonal influenza; this in turn reduces the likelihood of an immunized individual becoming infected with both human and avian forms of influenza at the same time. Should a person be infected with both viruses at the same time, there is a possibility that the two viruses could “mix” and mutate into a new virus that could spread efficiently and against which humans would have no immunity.

Several anti-viral drugs are available for the prevention and treatment of seasonal influenza in Canada. Although, none of the anti-viral drugs have been shown to prevent H5N1, studies done through the WHO Global Influenza Surveillance Network have shown that the anti-viral Oseltamivir may be effective in the treatment of A ( H5N1 ).

As a precautionary measure, the Public Health Agency of Canada recommends to avoid unnecessary contact with domestic poultry and wild birds. This includes poultry farms as well as markets where live and slaughtered animals such as chickens and ducks are sold, as these animals have been found to be carriers of the avian influenza A (H5N1) virus. Evidence suggests that the risk of infection is greatest in persons having direct contact with live and/or dead poultry including surfaces contaminated with their feces or secretions. Travellers should be aware that it is possible for the avian influenza A ( H5N1 ) virus to stick to hair and clothing, and may be inhaled.

Ensure that poultry prepared for consumption is thoroughly cooked to eliminate the risk of infection. Internal temperatures for whole chicken and parts should reach 82°C-85°C.
While to date there is no evidence that the virus is transmitted through contaminated food, it is always advisable to avoid undercooked or raw poultry dishes, including eggs and egg products.

Follow normal precautions regarding food storage, handling and preparation. Travellers are advised to maintain high standards of hygiene, including thorough hand washing, particularly after having contacted eggs or undercooked fowl and egg products and to avoid cross contamination with other food products. Using hot, soapy water and lathering for at least 20 seconds is the single most important procedure for preventing infections. This is because disease-causing micro-organisms can frequently be found on the hands. Alternatively, travellers can use waterless, alcohol-based antiseptic hand rinses. If there is visible soiling, hands should be washed with soap and water before using waterless antiseptic hand rinses. If soap and water are unavailable, cleanse hands first with detergent-containing towelettes to remove visible soil.

Source: Health Canada, 2005