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Bird flu: Are we ready?
By Kumudini Hettiarachchi
The warnings are coming fast and furious. It is red alert time - not just about an epidemic but a pandemic that could leave millions dead.
The culprit is a strain of the bird or avian flu - H5N1 - that has been around since 1997 in Asia and proved to be deadly for men, women and children who have caught it. Many countries have been affected so far, with the infection spreading in July this year to Russia and Kazakhstan and in August to Mongolia.

"The bird flu viruses are not easily picked up by human beings but this could change due to either a mutation or genetic reassortment," says Epidemiologist Dr. Nihal Abeysinghe explaining that reassortment means the mixing of human and animal influenza genes.

The World Health Organization (WHO) has warned that continuous transmission of avian influenza in poultry and human exposure in many countries increase the possibility of a pandemic virus emerging in the near future. Pigs infected with the avian, human or swine viruses could serve as the mixing vessels for the genetic material.

Experts agree that another influenza pandemic is inevitable and possibly imminent, according to the WHO. An epidemic is an outbreak of disease that affects a large number of people while an epidemic that goes global is dubbed a pandemic.

Historical patterns suggest that such pandemics can be expected to occur, on average, three to four times each century when new virus sub-types emerge and are easily transmitted from person to person.

The 20th century saw three influenza pandemics, with the 1918-1919 Spanish Flu affecting 25% of the total population and causing around 40-50 million deaths worldwide. The other two were in 1957-58 (Asian Flu) and 1968-69 (Hong Kong Flu).

Now that the warnings have come, is Sri Lanka ready for a pandemic that is seen as an unprecedented challenge for Asia?

"Yes," stresses Dr. Abeysinghe. "Contingency plans have been prepared in advance. A draft National Plan has been drawn up and is being fine-tuned. The National Plan will be finalized in three weeks." At a meeting on Thursday with the WHO, the plan was endorsed, The Sunday Times learns.

Sri Lanka is in the planning and preparedness phase in a major attempt to prevent the disease from hitting our shores. "We are also setting up the structures for the emergency and pre-emptive phase and in the worst-case scenario the pandemic phase," says Dr. Abeysinghe. "We have taken up the challenge. Surveillance of the virus and respiratory illness among humans is crucial."

The management structure to face a possible pandemic is being put in place.
A National Steering Committee, a Technical Committee and a National Focal Point have been identified and a programme secretariat is being set up to meet such an exigency.

The Advisory Committee on Communicable Diseases is the Steering Committee, with relevant experts being invited to join as and when necessary. The Technical Committee comprises 14 members from all the relevant disciplines. The National Focal Point is the Health Ministry's Epidemiology Unit and will deal with human infections.

The Agriculture Department and the Department of Animal Production and Health have also set up a similar three-tier structure with the National Focal Point dealing with animal infections being the latter.

"While keeping our eyes and ears open for any signs of the virus, we are also carrying out awareness programmes among different professionals and people, not only on prevention but also on the need for the flow of information,” says Dr. Abeysinghe seeking the support of public interest groups, especially the media. "An early warning system is essential."

With regard to the measures taken, he explains that orders have been placed for the import of a stock of anti-viral drugs just in case of an outbreak while the Epid. Unit and the Medical Research Institute are in touch with the Thai and Hong Kong laboratories — particularly Dr. Malik Peiris, the Sri Lankan based in Hong Kong who was part of a team that isolated the SARS virus -- that are engaged in research on this disease.

The Department of Animal Production and Health is also actively involved in the campaign. Says Additional Director-General Dr. A.P. Sritharan that currently the import of live poultry, poultry products and poultry by-products are allowed only from countries not affected by avian influenza.

"The import of parent stock is not allowed from disease-hit nations and the import of pet birds has also been restricted since January 2004 due to the bird flu. Each import consignment even from other countries of live poultry, poultry products and by-products such as feathers and skin which are used for sofas and jackets is subjected to quarantine inspection at the port of entry while samples are taken for laboratory investigation. The Customs Department is giving its fullest cooperation."

Explaining that all veterinary surgeons and also Agricultural Department personnel are being briefed on the need to be vigilant for even a minor indication of the bird flu, Dr. Sritharan says migratory birds could pose a danger. "October-November is the season when migratory birds come here. They leave in March-April. We know the areas where they congregate and have told our vets and farmers to be extra vigilant about dead birds and inform us immediately. We are carrying out random blood tests and also informing poultry farmers on the need to maintain a clean environment."

The Kelaniya University has already begun the screening of blood samples of animals including birds collected from different points, for the avian flu virus. "The university is in touch with us," said Dr. Abeysinghe. With these measures in place, hopefully, Sri Lanka may be able to ward off a flu pandemic.

What is influenza?
It is a very infectious, airborne respiratory disease that spreads from one person to another through sneezing and coughing. The symptoms include fever, cough, sore throat and muscle aches that can lead to pneumonia and acute respiratory distress.

Influenza viruses are of three types - A, B and C. While all affect humans, the viruses of the A type primarily infect lower animals and birds. All 16 H subtypes of influenza A can infect birds. All outbreaks of the highly pathogenic avian flu have been caused by the sub-types H5 and H7.
How does the bird flu virus spread?

The avian flu can affect domestic, wild and migratory birds. In chickens the symptoms are oral and nasal discharges, facial oedema with swollen and syanotic combs and wattles and conjunctivitis. There is a very high death rate among the flock.

Within a country the disease spreads when large amounts of virus are secreted in bird droppings, contaminating dust and soil. Equipment, vehicles, feed, cages or clothing, especially shoes, could get contaminated by the virus and spread from farm to farm or area to area. The virus can also be carried on the feet and bodies of animals such as rodents that act as 'mechanical vectors'. Limited evidence suggests that flies can also act as mechanical vectors. Markets where live birds are sold under crowded and unsanitary conditions can also be another source of infection. The airborne virus can also spread infection by being inhaled.

Droppings from infected wild birds can introduce the virus into both commercial and backyard poultry flocks. The risk that infection will be transmitted from wild birds to domestic poultry is greatest where domestic birds roam freely, share a water supply with wild birds or use a water supply that might become contaminated by droppings from infected wild-bird carriers. In Thailand, scavenger ducks have been identified as spreading the infection.
The virus can spread from one country to another due to trade in birds or through infected migratory birds which may not be sick or have only mild illness. Migratory water fowl - wild ducks - carry the virus but do not suffer from the disease.

Is there a vaccination?
Although vaccinations before and antiviral drugs during a pandemic are vital interventions to cut the morbidity and death rates among humans, the WHO warns that on present trends neither of these will be available in adequate quantities or would be equally distributed.

The global seasonal influenza vaccine production capacity is limited to 300 million doses annually and is concentrated mainly in Europe, North America, Australia and Japan. Most drug companies are reluctant to produce a vaccine for illnesses such as the flu because the viruses take on a different biological structure and millions of doses go waste. Even if all drug producers begin production of a pandemic influenza vaccine it would hardly be sufficient to cover 10% of the world's population, is the shocking disclosure by the WHO.
Sadly, there isn't a single influenza vaccine producer in the Southeast Asian region, says the WHO also lamenting the fact that none of the countries in this region includes this vaccination as part of the routine immunization programme.

- WHO information

Make farmers and public aware: Poultry Association
Stressing that Sri Lanka needs to "heed very seriously" the statement by the Food and Agriculture Organization that it is not a question whether the avian flu will come but when it will, the All-Island Poultry Association urged the authorities to make people, both the farmers and the public aware of what needs to be done if the disease hits the country.

"We know the Department of Animal Production and Health is drawing up a Preparedness Plan but we are a little concerned about the delay," said Dr. D.D. Wanasinghe, the association's President adding that there have been about 25 queries from them on what should done.

"How should they react? We have information that the carcass of a suspected bird flu victim should not be handled," he said. "That's why we need the department to notify us about the plan."

The association has on its roll 1,500 members but deals with all poultry farmers. According to Dr. Wanasinghe there are 75,000 farmer families directly involved in poultry production. "Six million kilos of chicken are produced per year in Sri Lanka," he said.

At a preliminary discussion with the department the association was informed that in the case of suspected avian flu, the farmers should immediately inform the veterinary surgeon in the area, who would then come in protective gear to take the dead birds to the testing centres.

"Our farmers are not that knowledgeable and we need to carry out awareness programmes. We are happy that the department has a surveillance programme in areas like Hambantota frequented by migratory birds," he said.
Dr. Sritharan of the department pointed out that since 2003 the vets, around 235, spread out across the country have been conscious of the avian flu threat.

“A detailed booklet in Sinhala on the disease is available for farmers. Once again the vets have been made aware of the persistent danger from avian flu and what action needs to be taken immediately. They are in the process of educating the farmers,” he said.

"The vet teams which would respond in the unfortunate event of an outbreak have been identified and protective clothing made ready. Our six Veterinary Investigation Centres are geared to meet emergencies.

“We have also got a stock of disinfectants ready. In the event of a culling campaign being necessary, the department is looking into the possibility of compensating the farmers," he added.

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