Bird Flu Fatigue Looming, warns WHO

MANILA, Oct 8 (IPS) - So where is the pandemic? This is a question most often asked of health experts years after they warned about a pandemic influenza that could infect up to 35 percent of the world's population.

The experts had say that pandemics are recurring events and that one was due any time.

They said a pandemic today, given the large volume of international travel, could reach all continents in less than three months and that the world's medical facilities will have difficulty coping with the huge number of sick people. They also pinpointed avian flu as the possible cause of the next pandemic.

However, there has been little news about avian influenza lately, compared to the highly publicised cases just a year ago. This development might be considered by some as a good thing, but it could also lull the public into a false sense of security, something that has left the Geneva-based World Health Organisation (WHO) worried.

An official of the WHO's Western Pacific Regional Office headquartered in Manila said people may be growing apathetic to the avian flu problem and could be letting their guard down in protecting themselves against the disease.

"I have observed 'avian influenza fatigue' or apathy among the people," said Dr Takeshi Kasai, regional adviser on communicable disease surveillance and response. "They think they have already done enough, and that is our worry in the WHO," he told IPS.

The first known case of avian influenza infection among humans was reported in 1997. The virus, the H5N1 strain in particular, crossed the species barrier and was transmitted from birds to humans through direct contact with infected poultry or surfaces contaminated by droppings.

According to the WHO, there have been a total of 387 avian flu cases among humans, with 245 fatalities. Most of the cases occurred in rural areas where poultry roam freely in homes and backyards. Countries with the most cases are Indonesia, Vietnam, Thailand, Egypt and China.

The most recent case was confirmed in September -- a man in Indonesia who had developed avian flu symptoms in July.

Health experts have been closely monitoring the H5N1 strain because it has already met two of three conditions that could spark an influenza pandemic (global epidemic). It is a new influenza virus subtype and it infects humans, causing serious illness. The third condition is that the virus spreads easily on a sustained basis among humans. If the H5N1 evolves into a form that is as contagious as normal influenza, it could start a pandemic.

"The risk that avian influenza could cause the next pandemic remains the same. It has not changed at all since 2003," Kasai said.

He said the avian flu virus continues to mutate. "In 1997 there was only one strain, now there are more than 10 groups," he said. "We have already seen changes in the virus."

As long as opportunities for human infections occur, the risk that the H5N1 virus will acquire the ability to cause an influenza pandemic will persist, the WHO said. And these opportunities will remain as long as the virus circulates in birds.

WHO is concerned that the H5N1 virus is now entrenched in many Asian countries, bringing with it the risk that more human cases will occur. Moreover, each new case gives the virus the opportunity to become more transmissible in humans.

Although the outbreak of avian flu in birds continues, the number of cases is still limited in humans, a development that Kasai sees as "good news." He said health education and information programmes could have contributed to the low infection rate among humans.

Delegates at a WHO regional meeting in Manila late September noted the considerable progress already made to improve "country-level" readiness for avian flu. Because of their strengthened capacity for surveillance and response, countries affected by the disease have been rapidly responding to human infections of the virus and gained the confidence of the public, the delegates noted.

The WHO has assisted countries in testing and validating their pandemic preparedness plans. Laos conducted rapid containment exercises in November 2007, followed by the Philippines in March 2008. Lessons learnt from these exercises will help develop programmes for pandemic influenza containment operations.

Several countries have also strengthened their infection control, laboratory bio-safety and field epidemiology training.

Acknowledging the WHO's contributions in containing avian flu in his country, Vietnamese Health Minister Nguyen Quoc Trieu pledged increased international cooperation in the public health sector.

Bird flu has infected 105 people in Vietnam and killed at least 51 of them since it first appeared in the country in late 2003. This year, bird-flu outbreaks were detected in 26 Vietnamese provinces, killing five people and forcing authorities to cull more than 60,000 ducks.

Although it is not known what H5N1 strain will cause the next pandemic or if it would be caused by the H5N1 virus at all, an H5N1 pandemic is still an important possibility. As such, the development of an avian flu vaccine remains a crucial part of the global strategy for pandemic preparedness.

At present, the available vaccines act only against a single strain of the virus. Large-scale commercial production of a vaccine against a pandemic virus can only start until the new virus has emerged and a pandemic declared.

According to Kasai, a number of countries have already stockpiled vaccines against the prevalent strain in their areas. But because the virus mutates quickly, it is important to further develop the vaccines.

Kasai said there are ongoing trials to determine whether receiving a vaccine against a single strain would increase one's chances of protection against other strains. "There is a theory that once your body has a memory against (one strain), it could boost your immunity against the other [strains]," he explained.

Kasai said countries must prepare for a pandemic because it will surely develop. "We think we've been very lucky" so far, "but we have a responsibility to tell the public that they should not stop preparing for it". (END/IPSAP/SG/JS/08)