About Yemen
Avian Influenza
Latest Updates:
Avian Influenza Prevention Guide
March 7, 2006
Ministry of Public Health & Population, Yemen
The Ministry released a guide for pilots with instructions to prevent the spread of Avian Influenza.
- Avian Influenza Prevention Guide (English, Arabic - PDF)
WHO Information Bulletin No. 3
October 17, 2005
Communicable Disease Surveillance, Forecasting and Response
WHO Regional Office for the Eastern Mediterranean
Why are we concerned?
The current avian influenza outbreaks are caused by a highly pathogenic influenza virus that may resort or mutate to adapt themselves to human strains. There are three prerequisites to start influenza pandemic: emergence of a novel virus, ability of the new virus to replicate and cause disease in humans and ability of the new virus to spread efficiently from human to human. The first two pre-requisites have already been met. The newly emerging avian influenza virus (H5N1) has already caused disease in about 117 cases; more than half of them (60) have already died. If H5N1 virus swapped some genetic materials from human and the avian H5N1, a reassortment process known as “antigenic shift”, a novel influenza subtype different from both parent viruses that could be able to replicate in humans and be efficiently and rapidly spread from person-to-person, thus, leading to a highly lethal influenza pandemic. The world will have no immunity to the new subtype; and no existing vaccines can confer protection against the novel influenza virus.
Influenza pandemics are known to severely affect and disrupt social and community daily activities, including travel, trade and medical services. This rising concern of having pandemic influenza could be attributed to emergence of unprecedented simultaneous large highly fatal outbreaks of H5N1 in nine neighboring Asian countries, most of which do have strong capacities to eliminate the disease. Prompt culling of Hong Kong’s entire poultry population (1997) probably averted a pandemic. The virus is now considered entrenched in many parts of Viet Nam and Indonesia and in some parts of Cambodia, China, Thailand, and possibly also Laos. During early August 2005, highly pathogenic H5N1 avian influenza was documented among poultry in parts of Siberia, Russia, adjacent parts of Kazakhstan and Mongolia, Turkey and Romania. Direct or indirect contact of domestic flocks with wild migratory waterfowl has been implicated as a frequent cause of epidemics. Domestic poultry, including chickens and turkeys, are particularly susceptible to epidemics of rapidly fatal influenza. However, domestic ducks could serve as carriers for the virus.
Past history:
The past history of the disease is also disquieting. In the last century, influenza pandemics in humans have resulted in 20 - 40 million deaths during the Spanish flu due to H1N1, 1918-19; 1 - 4 million deaths in 1957-58 (Asian flu due to H2N2,), and 1 - 4 million deaths in 1968 (Hong Kong flu due to H3N2). More than 27 years, median duration for inter-pandemic periods, has passed.
Is the Eastern Mediterranean Region at risk?
Yes. Infectious pathogens simply do not respect political borders. The world is becoming a small village and with the global network of airlines, travellers can spread influenza to almost all countries. The Eastern Mediterranean Region (EMR) is not an exception. The daily dynamic interaction with other countries in the world (expatriate workers, trade, religious visitors and tourism) could easily result in the introduction of influenza into the Region and further dissemination of influenza to the whole world. Migratory birds flyways pass through the EMR on their way between Asia, Europe and Africa. The EMR is the nearest region to the current focus of unprecedented outbreaks of avian influenza than any other WHO region outside of Asia.
Strategies of the World Health Organization:
The current WHO strategies are essentially geared towards risk reduction to avoid emergence of a new virus. Coordinated efforts with international organizations such as FAO and OIE are being made to eliminate animal reservoirs, reduce opportunities for human exposure to infected poultry (the largest reservoir of the virus) culling, slaughter and vaccination of birds, strengthening surveillance in animals and humans, and continuously improve pandemic preparedness of countries, among others. WHO will support and coordinate global public health response, support affected countries and will continue strengthening global influenza programme. Should the pandemic emerge, WHO will strive to implement focused and timely public health measures to slow down the national and international spread of the virus. WHO will facilitate vaccine development, access to antiviral drugs and encourage countries to develop national pandemic preparedness plans.
Current Status:
To date no confirmed human-to-human transmission of H5N1 is known to have occurred.
What is expected from countries?
All countries throughout the world need to work together to avert, delay and contain the anticipated pandemic. It would be a major coordinated global effort with full transparency and collaboration. The most important immediate intervention to contain emerging outbreaks of avian influenza is to rapidly and appropriately destroy all infected or exposed birds with proper disposal of carcasses. This is the first line of defence for both the protection of human health and the reduction of further losses in the agricultural sector.
Functional and efficient influenza surveillance hand in hand with focused and timely public health measures would slow down the national and international spread of the virus. All countries need to develop their own detailed (step by step) pandemic preparedness plans and undertake actions that ensure their implementation. The preparedness plans must be tailored to each country’s unique epidemiological situation and unique capacity, with health and agricultural sectors. Workers involved in the culling of poultry flocks must be educated and adequately protected with proper clothing and equipment, against infection should also receive antiviral drugs.
Oseltamivir (Tamiflu), the drug of choice for pandemic influenza, is not only a very expensive drug, but also would take many years to produce the needed amount given the current limited global production capacity of antivirals. As there will be no enough antiviral drugs for all infected person in most countries of the world, including the Eastern Mediterranean region, the preparedness plans should accommodate many non pharmaceutical control measures; e.g., to minimize crowding, control travel among others.
Countries need to have reasonable stockpiles of Tamiflu in place with clear guidelines on how to dispense them. Similarly, countries should have clear plans of actions on how to conduct vaccination against pandemic influenza and identification of the priority sectors of the population that would be vaccinated first.
Countries need to seriously consider the possibility of production of influenza vaccines.
As pandemic of severely disrupt daily life of all people, countries need to prepare plans of action to minimize anticipated chaos and reduce associated panic to minimum possible through an efficient communication system. Countries need to identify all national resources that could be made use of during the anticipated pandemic of influenza. Lines of leadership, coordination, communication and terms of reference of all people working in containment activities need to be well-defined and in place as soon as possible.
What is expected from Individuals?
People need to understand that pandemic influenza is not going to weep the whole world overnight. There will be a series of written, audiovisual messages educating the public on basic personal hygiene and to escape unprotected coughs and sneezes and transmission from hand to mucous membranes.
At this stage the public should avoid touching dead birds, hunting migratory birds and unnecessary visits to wet poultry markets. The public should be encouraged to report unusual deaths of clusters of wild birds or poultry.
Summary:
In summary, WHO considers the present risk of a pandemic great, but unpredictable in terms of its timing and severity. All conditions for the start of a pandemic have been met except one: changes in the virus that would make it contagious among humans, thus allowing easy and sustainable human-to-human transmission. The likelihood that this will happen is a matter of opportunity and probability. There is no need to panic but to be better prepared.