...issues and antiviral issues. It's entitled "WHO Guidelines on the Use of Vaccines and Antivirals During Influenza Pandemics." In addition to the report and recommendations, it contains very nice summaries of the present problems in vaccine production. I've seen a lot of misinformation and misunderstanding here lately about pandemic influenza (e.g. "it's propaganda," "no worries-- it's just the flu," "you can prevent it by eating/drinking/sleeping/thinking right," "why can't we just get vaccinated now?")-- hopefully this will clear some of that up.
www.who.int/entity/csr/resources/publications/influenza/11_29_01_A.pdf
Here are a couple of excerpts that I snipped-- most these were not contiguous in the original text (emphasis is mine). Mods, I included a few more than four paragraphs because this is a public document):
Conditions surrounding the 1997 Hong Kong outbreak of “chicken influenza” highlight the need for advance planning to ensure an adequate response to a health emergency that is certain to be unpredictable, complex, rapidly evolving and accompanied by considerable public alarm. Once a pandemic begins it will be too late to accomplish the many key activities required to minimize the impact. Therefore, planning and implementation of preparatory activities must start well in advance. Planning for pandemics will also enhance the capacity to respond to other large-scale health emergencies, including bioterrorist threats, that require mass access to prophylactic and therapeutic interventions and strong national plans which include a risk communication component to help calm public fears. The impact of pandemic influenza is likely to be far greater, by orders of magnitude, than most bioterrorism scenarios. Unlike most other health emergencies, pandemics occur in several waves and last one to two years. Response efforts will, therefore, need to be sustained for a prolonged period. In addition, preparation for an influenza pandemic will enhance the response to influenza epidemics, which occur each year and are thought to kill every year from 500 000 to 1 million people worldwide. Investment in pandemic preparedness thus has direct and immediate utility as a measure for reducing the impact of a certain and recurring event
<snip>
Influenza vaccines have been available for over 60 years. Extensive experience during this long period has demonstrated their safety and efficacy. In populations at risk of severe complications, vaccination is known to reduce hospital admissions and deaths. Vaccination is thus the cornerstone of influenza prevention. As influenza viruses are constantly evolving, vaccine is produced each year with a composition based on the most relevant strains of virus identified through a global surveillance system. Stockpiling of vaccine in preparation for a pandemic is not an option, as vaccine composition depends on the responsible virus and must await its appearance and identification at the start of the pandemic. Vaccine will thus be in limited supply during the first part of the pandemic, and may not be available at all in some parts of the world.
<snip>
Two doses of vaccine per person will likely be necessary for adequate protection in a pandemic situation. The implication for planning is that countries may need twice the amount of vaccine.
<snip>
Vaccination is the primary means of preventing influenza. At the beginning of a pandemic, vaccine supplies will be limited or non-existent. This is because the emergence of a pandemic is unpredictable, vaccine cannot be stockpiled and vaccine production can only start once the pandemic virus has been recognized. With current technology, the first doses of vaccine are unlikely to become available within the early months of the pandemic. A country not currently producing vaccine is unlikely to secure supplies. (Note: this refers to producing interpandemic flu vaccine, not the pandemic strain.--mike_c) Forward planning will be necessary to increase the likelihood that vaccine will progressively become available as the pandemic unfolds. Therefore, national or regional priorities need to be defined for the rational use of existing supplies according to predetermined objectives. These may differ from interpandemic priorities.
<snip>
With present technology, the current worldwide production capacity for influenza vaccine is able to cover less than 5% of the world’s population. It is recognized that there could be tremendous disparities in vaccine supply, especially in countries with no manufacturing capacity, for which there is no easy solution.
<snip>
The H1N1 pandemic of 1918-1919 was the most devastating in history with a total mortality of 40–50 million. In the United States, it killed 550 000 people, representing approximately 0.5% of the population. In Scotland, 1 in 200 to 1 in 300 of the population died. In England and Wales there were 200 000 deaths, and by December 1918, an estimated 4.9 million excess deaths (about 2% of the whole population) occurred in British India, the vast majority occurring within the space of two months. The mortality during the ‘Asian’ H2N2 influenza pandemic in 1957 was moderate in comparison. In England and Wales, mortality was estimated at 33 000 deaths. In the US, 80 000 deaths were attributed to influenza during the 1957-1958 and 1960 epidemics, with nearly half occurring in the first three months of the 1957-58 epidemic. During the ‘Hong Kong’ H3N2 pandemic of 1968, the mortality in the USA was estimated at around 30 000 deaths. In Britain, mortality was estimated at around 30 000 deaths as well. The pandemics in 1957 and 1968 affected all ages, with the greatest excess mortality occurring in the elderly and in people of all ages with underlying medical conditions. The re- emergence of H1N1 virus in 1977 affected young people mostly and the outbreak was benign in comparison with the episodes in 1957 and 1968. The mortality from pandemic influenza in many countries is unknown, but as the outbreak of influenza A/Panama/2007/97–like (H3N2) virus in Madagascar in August 2002 shows, it may be higher in societies with overcrowding, malnutrition, and poor access to health care.
The rate of spread of pandemics can be alarming. During the Asian and Hong Kong pandemics of 1957 and 1968, seeding of virus in Europe and North America occurred within three to four months of the first virus isolations in south-east Asia. The intercontinental spread of SARS in 2003 was more rapid. The opening up of tourism globally, and the recent vast increase in air passenger transport and land-based communications in most parts of the world, may hasten the spread of pandemic influenza. A common characteristic of pandemics is the increasing severity of successive waves of infection. If vaccines are not available for the first wave of a full-blown pandemic, their availability for subsequent waves should still be greatly beneficial.
Besides pandemics, there have been a number of ‘false pandemics’ and ‘pandemic scares’. Occasionally, the genetic mutations associated with antigenic drift can be so profound, as in 1947, that an established subtype causes a severe worldwide ‘false pandemic’. The inactivated vaccines that had recently been introduced were no longer protective. During the winter of 1950-1951, epidemics of H1N1 virus reached major proportions throughout Europe, causing 50 000 deaths in the United Kingdom alone.
A ‘pandemic scare’ or ‘false alarm’ occurs when a novel virus is isolated from human beings, but it fails to spread and does not cause widespread illness. The public health response to a false alarm can have major societal costs. For example in 1976, the outbreak of H1N1 swine influenza in military trainees at Fort Dix, New Jersey, USA, led to the production of 150 million doses of vaccine and the vaccination of 45 million people. In December 1997, all chickens in Hong Kong (approximately 1.5 million) were slaughtered, first to prevent the transmission of avian H5N1 influenza to humans, and second to prevent genetic reassortment in human beings into a more transmissible strain. The territory’s entire poultry population was once again slaughtered when highly pathogenic A/Hong Kong/97 (H5N1) virus re-emerged in flocks in May 2001. Subsequently, a further 900 000 birds were killed in February 2002, and another 30 000 were killed in April 2002.
The events in history show that the recovery of a novel influenza subtype from man has the potential to become a public health emergency, even if the ensuing pandemics resemble the 1957 and 1968 episodes than the calamity of 1918. Past pandemics have occurred unpredictably and with little warning, emphasising the need for ongoing, intensive, worldwide surveillance, and flexible contingency plans that are capable of responding efficiently to a pandemic threat.
I've got to run to work-- my students are insisting on a lab cleanup day and I'm gonna be late-- but I'll check back into this thread in a few hours.
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