EINet Alert ~ Sep 30, 2005

*****A free service of the APEC Emerging Infections Network*****
APEC EINet News Briefs offers the latest news, journal articles, and notifications for emerging infections affecting the APEC member economies. It was created to foster transparency, communication, and collaboration in emerging infectious diseases among health professionals, international business and commerce leaders, and policy makers in the Asia-Pacific region.
In this edition:
- Global: WHO expert to work with the UN system on avian and human influenza
- Global: Global strategy to fight bird flu in animals faces serious funding gap
- South East Asia: Cumulative number of human cases of avian influenza A/(H5N1)
- Indonesia: Tourism industry asking for more transparency
- Indonesia: Difficulties in culling of animals
- Indonesia: Foreign assistance for avian influenza
- Indonesia: At least 54 people being treated for avian flu; additional fatal case
- Cambodia: Mystery illness in ducks; reportedly not avian influenza
- Russia: OIE Seminar and Avian influenza report
- Japan (Ibaraki): H5N2 Avian influenza outbreak
- USA: NIAID, MedImmune team up to develop pandemic flu vaccines

1. Articles
- CDC EID Journal, Volume 11, Number 10-Oct 2005
- Avian Influenza A (H5N1) Infection in Humans
- Efficacy and effectiveness of influenza vaccines in elderly people: a systematic review.

Global: WHO expert to work with the UN system on avian and human influenza
The UN Secretary General appointed Dr. David Nabarro, one of the most senior public health experts at the WHO, to lead coordination of the UN response to avian influenza and a possible human influenza pandemic. The appointment is critical as the world is fast recognizing the risk of a human influenza pandemic, and is taking steps to reduce the risk and to get prepared. Nabarro said he was nearly certain that a pandemic will erupt soon and predicted it could kill anywhere from 5 million to 150 million people. Nabarro warned that the world will have only "a matter of weeks" to respond after a pandemic begins and before it gets out of control. He said health agencies will have to fight the virus with oseltamivir and the most potent vaccines available. He also expressed concern about the possibility that migratory birds will spread avian flu to the Middle East and Africa. An outbreak in poor, war-torn parts of Africa, could lead to "a nightmare scenario," he said. WHO has sent all countries detailed guidance on actions they need to take. Implementing these actions requires coordination across UN agencies, countries, civil society, across sectors within countries and the private sector. Implementation also requires funding.

As Senior UN system Co-ordinator for Avian and Human Influenza, Dr. Nabarro will be responsible for ensuring an effective and coordinated contribution by the UN system to controlling the current epidemic of avian influenza that is particularly affecting countries in Asia. He will also ensure that the UN system supports effective local, national, regional and global preparations for a potential human influenza pandemic - so as to reduce the human toll, as well as the economic and social disruption, that this pandemic could cause. Dr. Nabarro has held several leadership positions in WHO, including on malaria, environmental health, food safety and most recently in crisis operations. His 30 years experience includes work in community-level and government health programmes, particularly in Asia, in the administration of development assistance, as well as the management of scientific research, the building of development partnerships and engagement with non-governmental organizations.

Several countries have joined forces to coordinate preparation. The US announced a new International Partnership on Avian and Pandemic Influenza at the World Summit. The initiative is moving forward with several countries, with a planning meeting 7-8 Oct 2005. Canada is also hosting a ministerial meeting October 25 and 26, 2005, to discuss a range of policy issues to support the work. On 7-8 Nov 2005 WHO is hosting a meeting of all partners to coordinate the funding needed. All of these efforts aim to ensure countries are equipped with national influenza pandemic preparation plans, that efforts to stop the outbreaks of avian influenza are accelerated, and that health tools, such as a vaccine are available as quickly as possible. (WHO 9/29/05 http://www.who.int/mediacentre/news/releases/2005/pr45/en/index.html and CIDRAP 9/29/05)


Global: Global strategy to fight bird flu in animals faces serious funding gap
The global strategy for the control of avian influenza in animals remains largely under-funded despite important contributions pledged by some donors. "It makes sense to stockpile antiviral drugs to protect humans against a potential avian influenza pandemic, but at the same time we have to contain the virus at source, in animals, to reduce the risk to people," said FAO's Chief Veterinary Officer Joseph Domenech. "Strong national veterinary services are essential to improve the early detection of avian influenza. The rapid exchange and analysis of virus samples require additional resources to immediately respond to avian influenza outbreaks," he said. The “Global Strategy for the Progressive Control of Highly Pathogenic Avian Influenza” launched by FAO, the World Animal Health Organization (OIE) and in collaboration with the WHO in May 2005, for control programmes in Southeast Asia, has called for over $100 million for the next three years. To date, donors such as Germany ($6 million), Switzerland ($4 million), the US ($6 million) and Japan ($0.5 million) have pledged around $16.5 million. FAO will provide another $2 million. The World Bank and the European Commission are also planning to heavily invest in controlling bird flu. "This support is excellent, but it marks only a starting point and unless it translates into further financial funding to support affected countries, the cycle of bird flu infection that will occur in poultry this winter will not be stopped," Domenech said.

There is still a small window of opportunity before winter to reduce the levels of infection through vaccination of poultry. In countries like Viet Nam it is the only way that the levels of infection can be dampened down in the short time available. It involves mass vaccination of poultry, especially in the smallholder sector. Thailand has successfully managed to control the avian flu virus and no additional human cases have been reported recently. Viet Nam has already embarked on an ambitious program to vaccinate all poultry in provinces at risk. The country will need an additional $10 million to implement its vaccination programme, upgrade laboratory facilities and ensure post vaccination surveillance programmes. Indonesia also needs strong financial support to improve the efficiency of ongoing vaccination campaigns.

FAO called again upon countries along the pathways of wild birds to set up early warning and surveillance programmes. India and Bangladesh, Central Europe, the Middle East and parts of Africa should develop national prevention, early detection and rapid response plans. "These national activities will require additional donor support of around $50 million for the next three years," Domenech said. The major part of these funds should be used for awareness building, training, protective equipment, the upgrading of laboratories and the surveillance of wildlife and poultry farms. National resources by countries at risk will not be sufficient to finance their control strategies. On the global level, monitoring, coordination and the work of reference laboratories should be supported. Investing today in the control of the bird flu virus in animals is cheap compared to the costs of a global pandemic that could occur tomorrow. (FAO 9/26/05 http://www.fao.org/newsroom/en/news/2005/107804/index.html)


South East Asia: Cumulative number of human cases of avian influenza A/(H5N1)
Cumulative number of confirmed human cases of avian influenza A/(H5N1), 16 Dec 2004 to present:

Economy / Unofficial (Official) Cases / Unofficial (Official) Deaths
Indonesia / 7 (4) / 5 (3)
Cambodia / 4 (4) / 4 (4)
Thailand / 0 (0) / 0 (0)
Viet Nam / 68 (64) / 23 (21)
Total / 78 (71) / 31 (27)

Cumulative number of confirmed human cases of avian influenza A/(H5N1), 3 Dec 2003 to present:
123 (116) / 64 (60)
(CIDRAP 9/29/05 http://www.cidrap.umn.edu/cidrap/content/influenza/avianflu/case-count/avflucount.html)


Indonesia: Tourism industry asking for more transparency
Tourism industry players have called on the government to be more transparent in informing the public about the bird flu outbreak to avoid confusion that could be harmful to the industry. Although the country's tourism sector is yet to experience a significant impact from the outbreak, Indonesian Hotel and Restaurants Association (PHRI) chairwoman Yanti Sukamdani Hardjoparkoso said the industry could face another downturn as it did in 2003 -- when SARS swept across Asia -- if the government failed to seriously handle the situation. "Look at what happened to Ragunan Zoo," Yanti said. "People may never want to visit the zoo again after the government was so wishy-washy about whether the place was safe from bird flu or not." Although tests had shown 19 birds carried the bird flu virus, Jakarta's Ragunan Zoo was kept open on Sunday for thousands of visitors. Several of those since taken to hospital were zoo visitors. The government closed down the zoo for 21 days starting 19 Sep 2005.

Yanti said the government needed to assess the situation and take preventive measures -- including specifying tourist destinations that should be avoided for the meantime -- rather than waiting for a tourist to fall ill, which would only do the tourism industry more harm. "Tourists are actually more afraid of -- and more likely to be traumatized -- by the outbreak of a disease than a terror attack; it is always more difficult and costly to restore the good image of a tourist destination afterward, than (to take measures) before it is tarnished," she said. The Association of Indonesian Tour and Travel Agencies (ASITA) chairwoman Meity Robot said, "The government must, most importantly, provide clearer and more complete information on the situation to the public and be resolute in taking preventive measures against the outbreak," she said.

The government has been hoping to attract 6 million foreign tourists this year, which would generate USD 5.8 billion in foreign exchange from the industry -- higher than last year's 5.3 million tourists and USD 5 billion in revenues. The number of foreign arrivals during the year's first 7 months was 2.45 million, according to the Central Statistics Agency, down 4.08 per cent from the same period in 2004. Indonesia's tourism sector has been in the doldrums since the Bali bombings in 2002 and terror attacks the following years. At the same time, a series of SARS and influenza epidemics in the region, as well as the Dec 2005 tsunami, made things worse. The occupancy rates of hotels in the country dropped from an average of 55 percent to 30 percent during the SARS outbreak, PHRI said.

Despite the government's earlier warning that the outbreak could turn into an epidemic, several foreign embassies are yet to issue travel advisories to their citizens concerning the bird flu. The Japanese Embassy has notified Japanese citizens of the bird flu outbreak, but it has not issued an advisory suggesting they defer travel to the country. The Australian government has asked Australians residing in avian-flu-affected areas not to panic and to take precautionary measures. There are more Japanese and Australian tourists here than visitors of any other nationality. (Promed 9/24/05)


Indonesia: Difficulties in culling of animals
The lure of free entertainment on Sunday drew hundreds to a field near the village of Babat to witness the first mass cull of pigs infected with bird flu virus. Adults and children milled around, watching animals being slaughtered, thrown into a pit and burnt with no sign of public safety precautions. The Indonesian Agriculture Minister, Anton Apriantono, shouted to staff to find if it was safe to remove his mask to answer questions. "Don't blame me if you get bird flu because you don't wear a mask. This is very dangerous, you know, as the virus can be transmitted through the air," he warned reporters. Only 31 pigs and 40 ducks from Tangerang region were being culled, instead of the promised hundreds of infected pigs and thousands of chickens. "We only culled the infected animals as we do not have the money to carry out a mass culling," he said.

The UN FAO demanded Indonesia improve its virus control and immediately start culling in infected areas. In April tests at pig farms uncovered bird flu infections, but no cull was ordered. The WHO's regional spokesman, Peter Cordingley, believes Indonesia is now the "hot spot" for bird flu, and the WHO's country representative, Georg Peterson, describes it as the "weak link" in global efforts to avert a pandemic. Mr Cordingley said the WHO has known "for some time the H5N1 virus is entrenched in Indonesian poultry populations". The health minister, Siti Fadilah Supari, at first denied the possibility of human transmission, then stated it was inevitable and Indonesia was in the grip of an epidemic. She later reversed her position, saying the outbreak could possibly become an epidemic and called on the nation to increase "alertness". But Mrs Supari's flu alert was attacked by other cabinet ministers on the grounds it could harm tourism and investment. This week culls in "highly infected" areas were finally announced—only if more than 20 per cent of stock were infected. President Susilo Bambang Yudhoyono urged the culling of birds in infected areas but warned against overstating the threat. Mr Cordingley said, "There is no incentive for somebody who raises chickens to report infected chickens if he is not going to be compensated for the day government authorities come in and kill all his chickens," he said. (Promed 9/24/05)


Indonesia: Foreign assistance for avian influenza
Health Minister Siti Fadillah Supari said 20 000 doses of the anti-viral drug Tamiflu were expected to arrive in Indonesia soon and a further 20 000 would come by the end of this week. Australian Foreign Minister Alexander Downer said Canberra will pay for a further 40 000 doses of the anti-viral drug Tamiflu for Indonesia, on top of an initial 10 000 doses that Canberra said it would fund. Tamiflu will be sold commercially at pharmacies. So far, it has only been available in hospitals. The Japanese government will send a team of experts to Indonesia to help it find appropriate measures to combat avian influenza. The team comprising 5 experts are expected to work for around one week, said Deputy Japanese Ambassador to Indonesia, Masafumi Kuroki. Kuroki said the Japanese government's decision to send experts to Indonesia was made at the request of the Indonesian government. "The team will gather information about bird flu outbreak and give input to the Indonesian government about how to handle the disease," he said.

The Indonesian government plans to enhance hospitals across the world's fourth most populous country to cope in the event the number of bird flu patients rises. Despite a growing number of patients being treated for suspicious respiratory illnesses in a Jakarta hospital, WHO said, "Current investigations in Indonesia have produced no evidence that the H5N1 virus is spreading easily from person to person." Consequently WHO has not raised its level of pandemic alert. WHO has said that tests on samples from the 37 year old Indonesian woman who died of avian flu earlier this month showed that the virus had not mutated. Indonesia's recent cases have heightened global concerns. The US military was planning for a possible bird flu pandemic to ensure its forces could respond quickly, Admiral William Fallon, the US Pacific military commander, said. He had discussed bird flu with military chiefs throughout the region, and said the issue would be high on the agenda at a meeting of US defense chiefs in Hawaii next month. (Promed 9/24/05, 9/27/05, 9/28/05)


Indonesia: At least 54 people being treated for avian flu; additional fatal case
At least 54 (57 according to another source) people were being treated 28 Sep 2005 for suspected avian influenza in Indonesia, where the disease had already claimed 6 lives (unofficially). Deputy director of Jakarta's Sulianto Saroso hospital, Sardikin Giriputro, said they would soon discharge 3 of 20 suspected bird flu patients, after tests gave them a clean bill of health (2 adult men and one 2-year-old infant). The latest suspected case, a 23-year-old man from the capital, was admitted to the hospital 27 Sep 2005. Blood and mucus samples from the patients were being tested locally, and any results indicating bird flu would be sent to WHO laboratories for confirmation.

The Ministry of Health in Indonesia has confirmed 29 Sep 2005 another fatal human case of H5N1 avian influenza. The patient, a 27-year-old woman from Jakarta, developed symptoms on 17 Sep 2005, was hospitalized 19 Sep 2005, and died 26 Sep 2005. Confirmatory testing was conducted at a WHO reference laboratory. Initial investigation has revealed that the woman had direct contact with diseased and dying chickens in her household shortly before the onset of illness. The woman is the fourth laboratory-confirmed case of H5N1 infection in Indonesia. As a result of intensified surveillance and heightened public concern, growing numbers of people with respiratory symptoms or possible exposure to the virus are being admitted to hospital. Until a conclusive diagnosis is made, these patients are classified by the Ministry of Health as suspect cases. While many do not have symptoms compatible with a diagnosis of H5N1 infection, screening of patient samples is being undertaken in national laboratories as part of efforts to ensure that no new cases are missed.

Lab testing to confirm human infection with H5N1 avian influenza is technically difficult; some tests produce inconclusive or unreliable results. To ensure a reliable assessment of the situation in Indonesia, authorities are, after initial screening, continuing to send samples from people considered likely to have H5N1 infection to WHO reference laboratories. Highly pathogenic H5N1 avian influenza is now endemic in poultry in many parts of Indonesia. As influenza virus activity in Indonesia may increase during the wet season, from November to April, human exposure to animal virus could be greater during the coming months. The deceased patient now confirmed by WHO as the fourth death from avian influenza virus in Indonesia is the patient whose samples had given inconsistent test results when tested in Jakarta. The status of the 2 additional fatal cases identified by the Indonesia authorities is still unclear. (Promed 9/28/05, 9/29/05)


Cambodia: Mystery illness in ducks; reportedly not avian influenza
In Cambodia, authorities sprayed vaccine at 7 north western farms containing nearly 16 000 ducks as a precaution after a mystery illness decimated the flocks, even though tests so far had proved negative for bird flu. A senior official from the agriculture ministry's department of animal health confirmed that concerned duck farmers had first reported mass deaths and illness in the flocks at farms just outside the north western city of Battambang 11 Sep 2005. He said despite initial tests proving negative for the H5N1, the birds were continuing to die in large numbers and no cause had as yet been identified. "We are spraying the farms as a precaution because the results returned on 13 Sep from initial tests were negative for H5N1, as were tests results returned to us from the lab yesterday, but ducks there are still dying," the official said, adding that the 7 farms under observation supported around 15 480 ducks, and Battambang, which lies just 20 km to the south of the affected farms, is a major transport hub for livestock and goods arriving from the nearby border with Thailand. At least 1000 ducks had succumbed to the mystery illness. (Promed 9/23/05)


Russia: OIE Seminar and Avian influenza report
The World Organisation for Animal Health (OIE) welcomes the world partnership against bird flu as an important step in dealing with a potential human pandemic, while recalling the importance of controlling the disease at its animal source. Returning from Russia where he participated in the OIE Seminar on the "Structure of national Veterinary Services of OIE Member Countries in Europe", the OIE Director General, Dr Bernard Vallat, said, ". . . The public is becoming increasingly aware of the global benefit of the work done by Veterinary Services in the field of prevention of zoonoses. The present concern about the spread of avian influenza is a very good example of how important it is to make relevant public resources available for efficient national veterinary services which are crucial not only to agricultural economies, public health including food safety, but also to the prevention of potential human pandemics." Furthermore, Dr Vallat accepted that an international assessment of the epidemiological situation of wild birds coordinated by the OIE be urgently carried out in Siberia prior to their migration.

Bird flu virus has been officially confirmed in 49 Russian settlements, and bird flu is suspected in another 81 settlements. Quarantine measures have been lifted in 24 Russian settlements. Russia has been given permission to resume poultry exports to the EU, the head of the Federal Veterinary and Phytosanitary Control Service Sergei Dankvert said. The European Commission banned poultry exports from Russia 17 Aug 2005. Dankvert said that representatives of EU veterinary services 20 Sep 2005 voted in favor of introducing a system in which poultry exports would not be banned from the country as a whole, but just from the regions where bird flu was registered. The decision of the EU to allow resumed imports of poultry from unaffected regions in Russia is based upon the principle of Zoning (or regionalization). According to article 1.3.5 of the International Animal Health Code, Member Countries may establish and maintain a subpopulation with a different animal health status within national boundaries. (Promed 9/24/05)


Japan (Ibaraki): H5N2 Avian influenza outbreak
Information received from OIE, from the Ministry of Agriculture, Forestry and Fisheries, Tokyo:
Precise identification of agent: low pathogenic avian influenza virus subtype H5N2. Since 23 Aug 2005, 21 additional outbreaks have been detected and now the number of infected farms is 31 in total. Surveillance conducted at the national level, targeting commercial poultry farms in each prefecture, is due to be completed 22 Sep 2005. None of the affected chickens showed clinical signs of the disease. The source of outbreaks or origin of infection is unknown. Epidemiological investigations to elucidate the cause of these outbreaks are continuing. Control measures undertaken include: partial stamping out; quarantine; movement control inside the country; screening; zoning; disinfection of infected premises/establishment(s); vaccination was prohibited.

The detection of H5N2 seropositivity in 31 farms without even a single clinical case strengthens the previously raised suspicions that this event is related to the illegal use of an H5N2 vaccine. The source of such a vaccine could be local (produced without authorization) or external (smuggled). There are several countries where such vaccines are known to be produced, including Mexico and China. The Japanese government decided to ask Mexico to provide information of unauthorized vaccine. There was unconfirmed information of usage of unauthorized vaccine in Mexico. A Mexican farm official denied 27 Sep 2005 Japan's suspicion that illegal bird flu vaccines from Mexico may have been linked to recent outbreaks of avian influenza in Japan. "No one has virus to produce vaccine besides those we preserve in this office," Jose del Valle, general director in charge of animal health at the Agriculture and Fisheries Ministry, said. He indicated the ministry has strict control over production of vaccines.

Control of production, testing, and distribution of animal vaccines is an essential part of animal disease control programmes; governments are responsible for their approval and certification. Chapter 1.5.2. of OIE's Terrestrial Animal Health Code deals with risk analysis for veterinary vaccines. A new version of chapter 2.7.12 thereof, dealing with avian influenza, was adopted by the General Session in May 2005; see <http://oie.int/eng/normes/mmanual/A_00037.htm>. Japan experienced a similar situation in August 2004, when they discovered that an outbreak of classical swine fever in Kagoshima had been caused by an unauthorized vaccine. In view of the vital role vaccines play in disease control and the risks related to the use of unauthorized vaccines, intensification of law enforcement, coordinated internationally, deserves prioritization. (Promed 9/25/05, 9/29/05)


USA: NIAID, MedImmune team up to develop pandemic flu vaccines
The US government and MedImmune Inc. will collaborate to develop vaccines for potential pandemic strains of influenza, using the technology that was used to create the company's nasal-spray flu vaccine, FluMist. The company said, "MedImmune scientists will work together with leading researchers of the NIAID Laboratory of Infectious Diseases to produce and test versions of MedImmune's attenuated, live intranasal influenza vaccine for use against different types of potential pandemic influenza strains, including one based on H5N1". The plan calls for inserting "selected genes from avian flu viruses with pandemic potential into a weakened human flu virus" to create several live virus vaccine candidates. The NIAID part of the effort will be led by Kanta Subbarao, MD, MPH, and Brian Murphy, MD. HHS Secretary Mike Leavitt said the partnership "will help speed the process of developing vaccines we will need to fight an outbreak if the avian flu starts to spread rapidly through the human population." NIAID Director Anthony S. Fauci, MD, said he couldn't predict how long it might take to ready the first candidate vaccines for clinical trials. "But given the fact that these are things we do regularly, I wouldn't be surprised if the first one went into clinical trials in a year or two," he said.

NIAID and MedImmune will develop at least one vaccine for each of the 16 different forms of hemagglutinin. The partners "will develop vaccines for the highest priority hemagglutinin subtypes first," HHS said. ". . . Having effective vaccines against all subtypes will help us prepare for influenza pandemics in the future, explains Dr. Subbarao." Fauci said there is no preset time frame for the collaboration. HHS and MedImmune officials wouldn't say how the partnership will work financially. The company said live attenuated vaccines may generate a broader immune response than injected vaccines. "One of the unique attributes of FluMist is that it provides both local and systemic immunity," said Stephen. Fauci added, ". . . Virus drifts from the original vaccine, so you want a vaccine that covers that drift. Live vaccines do that better than killed vaccines." The plan calls for the partners to use reverse genetics and "classical reassortment" to insert hemagglutinin genes into a weakened human flu virus. Reverse genetics is the use of lab methods to "custom make" a vaccine by assembling genes that code for desired features. Reassortment is the exchange of gene segments between two different viral strains inside a host cell to create a new strain. The government is already building a supply of an experimental vaccine for the H5N1 virus. The first clinical trial results were announced in August, and HHS announced Sep 15, 2005 the award of a $100 million contract to Sanofi Pasteur. (CIDRAP 9/28/05 http://www.cidrap.umn.edu/cidrap/content/influenza/panflu/news/sep2805medimmune.html)


1. Articles
CDC EID Journal, Volume 11, Number 10-Oct 2005
CDC Emerging Infectious Diseases Journal, Volume 11, Number 10-Oct 2005 issue is now available at: http://www.cdc.gov/ncidod/EID/index.htm. The following new expedited article is available: Highly Pathogenic Avian Influenza H5N1, Thailand, 2004, T. Tiensin et al. (CDC EID October 2005)


Avian Influenza A (H5N1) Infection in Humans
The Writing Committee of the World Health Organization (WHO) Consultation on Human Influenza A/H5
“An unprecedented epizootic avian influenza a (h5n1) virus that is highly pathogenic has crossed the species barrier in Asia to cause many human fatalities and poses an increasing pandemic threat. This summary describes the features of human infection with influenza A (H5N1) and WHO Meeting on Case Management and Research on Human Influenza A/H5, which was held in Hanoi, May 10 through 12, 2005. Because many critical questions remain, modifications of these recommendations are likely. . .” (CIDRAP; NEJM 9/29/05 http://content.nejm.org/cgi/content/full/353/13/1374)


Efficacy and effectiveness of influenza vaccines in elderly people: a systematic review.
Jefferson T, Rivetti D, Rivetti A, et al. Lancet 2005;Sep 22 (early online pubication)
Researchers who reviewed 64 studies report that influenza vaccination is only modestly beneficial for elderly people overall, with nursing home residents benefiting more than people living on their own. "Our findings show that, according to reliable evidence, the effectiveness of trivalent inactivated influenza vaccines in elderly individuals is modest, irrespective of setting, outcome, population, and study design," says the report by Tom Jefferson et al., of the Cochrane Vaccines Field. The researchers found that flu vaccines, when well matched to circulating flu strains, reduced the risk of hospitalization for flu or pneumonia by 45% for elderly (65 or older) nursing home residents. For people living at home, flu vaccines were 26% effective in preventing hospitalization for flu or pneumonia. However, vaccination didn't significantly lower the risk of laboratory-confirmed influenza in either group.

The team searched five databases for studies of the effectiveness of flu vaccine in preventing influenza, flu-like illnesses, and related hospital admissions, complications, and death. They found 64 studies from the past four decades, including five randomized trials, 49 cohort studies, and 10 case-control studies, that met their criteria. For elderly residents of nursing homes who received vaccines well matched to circulating flu strains, the vaccines yielded risk reductions of 23% for flu-like illness, 46% for pneumonia, 45% for hospitalization for flu or pneumonia, 42% for death from flu or pneumonia, and 60% for death from any cause. However, vaccination yielded no significant benefit when the match with circulating flu strains was poor or unknown.

The benefits were smaller for elderly people living in the community. Vaccines didn't significantly reduce the participants' risk for flu, flu-like illness, or pneumonia. With well-matched vaccines, risk reductions were 26% for hospitalization for flu or pneumonia and 42% for all-cause mortality. Vaccines did not reduce the risk of hospitalization for heart disease or the risk of death from respiratory disease. However, vaccination looked somewhat more beneficial for community dwellers when the authors adjusted for confounding variables, including sex, age, smoking, and other illnesses. The authors write that no firm conclusions could be drawn from the five randomized controlled trials they analyzed.

The study's main findings show somewhat smaller benefits than those cited by CDC. CDC continues to emphasize that vaccination remains the best way to protect older people from flu and its complications. The agency acknowledged that flu vaccines are not 100% effective and that older people and those with chronic diseases may develop less immunity than healthy young adults. The study authors write, "We believe efforts should be concentrated on achieving high vaccination coverage in long-term care facilities coupled with a systematic assessment of the effect of such a policy. One possible way to improve this strategy might involve the vaccination of carers [caregivers] in an effort to reduce transmission." The federal government took steps in that direction last month, announcing that nursing homes that serve Medicare recipients would be required to offer flu shots to residents. The government also wants to increase vaccination coverage for nursing home staff members, but there are no plans to require vaccination for them. CDC has recommended that flu shots be reserved for the high-risk groups until Oct 24. (CIDRAP 9/23/05 http://www.cidrap.umn.edu/cidrap/content/influenza/general/news/sep2305vaccine.html)