World is ill-prepared for "inevitable" flu pandemic
The recent avian influenza outbreaks in Asia serve as stark reminders that another influenza pandemic is inevitable and possibly imminent, said WHO Director-General, Dr LEE Jong-wook, during a conference on influenza preparedness hosted by WHO on 16-18 March 2004.
"We know another pandemic is inevitable," said LEE. "It is coming. And when this happens, we also know that we are unlikely to have enough drugs, vaccines, health-care workers and hospital capacity to cope in an ideal way."
Poultry culling and other measures may have reduced the likelihood of a human pandemic influenza strain emerging soon from Asia as a consequence of avian flu. However, experts believe that because these outbreaks come in cycles, a human influenza pandemic must be expected at some time in the future. (See related editorial, Avian flu and pandemic influenza, on p. 242 in this month's issue of the Bulletin.)
The three-day global consultation on priority public health interventions before and during an influenza pandemic brought together experts from all regions on influenza, public health, health economics, health policy, drugs and pharmaceuticals, infection control measures, disease surveillance, modelling and risk communication.
Objectives of the meeting included the identification of practical measures and feasible interventions aimed at increasing access and use of vaccine and antivirals, sound public health measures that may slow down the initial spread of a pandemic virus and reduce its impact on the population, and surveillance strategies that would rapidly detect a new pandemic virus and monitor its spread.
Epidemiological models indicate that an influenza pandemic will pose a major disease and economic burden both in developed and developing countries. "Once a pandemic has begun, we must be ready to implement without delays the key activities required to minimize its impact. Therefore the planning and implementation of preparatory activities must start well in advance," said Dr Marja Esveld from WHO's department of Communicable Disease Surveillance and Response. "Few countries have so far developed and approved influenza pandemic preparedness plans."
Participants heard that whilst vaccines remain the most important public health intervention, they will not be available in the initial stages of a pandemic since it takes at least four to six months just to begin vaccine production once a new strain of the virus has been identified. Another problem could be inequitable access, with vaccines being used first in the few countries that have production capabilities.
"Antivirals, combined with public health measures, could help buy time for vaccine development," said Esveld.
The consultation called for the establishment of a task force to explore the possibility of a global stockpile of antiviral drugs for use in the early phases of a pandemic. Since antirvirals are in short supply, particularly in developing countries, their use would have a minimal impact later in the pandemic.
All participants agreed on the need to strengthen both human and animal influenza surveillance systems including laboratory facilities, in close collaboration with the agricultural sector.
Whilst the annual occurrence of seasonal influenza epidemics represents a major health and economic burden for developed countries, little is known about the impact of influenza in developing countries. However, influenza outbreaks in the tropics where viral transmission normally continues year-round tend to have high attack and case-fatality rates. For example, during an outbreak in Madagascar in 2002, more than 27 000 cases were reported within three months resulting in 800 deaths despite rapid intervention.
"More information on the burden of disease could help improve political commitment to invest in influenza control and pandemic preparedness," said Esveld.
Slowing the spread of a pandemic and reducing its impact will require planning, preparation and global coordination. "When the next pandemic emerges, we will be able to respond properly only if we prepare properly," said LEE.
For the latest updates on the human and avian influenza situation, visit: http://www.who.int/csr/don/en/