Global Agenda on Influenza

Global Agenda on Influenza

470 News & Comment TRENDS in Microbiology Vol.9 No.10 October 2001 of England having nearly double the rate of the rest of the country. CK http://w...

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News & Comment

TRENDS in Microbiology Vol.9 No.10 October 2001

of England having nearly double the rate of the rest of the country. CK

Hepatitis G virus slows HIV

New clues in old ‘flu mystery

Coinfection with an apparently harmless virus could explain why HIV infection progresses more slowly in some people than in others. Recent clinical trials and cell culture studies support earlier findings suggesting that GBV-C (also known as hepatitis G) retards the progression of HIV infection. Following a 12-year study, researchers from the University of Iowa College of Medicine and the Iowa City Veterans Affairs Medical Center, report that patients infected with HIV alone were 3.68 times more likely to die than those who were also infected with GBV-C. Like HIV, GBV-C infects T helper cells, and in in vitro coinfection, HIV production was reduced by 30–40%. Although the results are promising, the researchers are warning HIV patients not to infect themselves with GBV-C intentionally; the long-term effects of GBV-C infection are unknown. AV category=Canada&story=/news/2001/09/06/ hiv_hepg010906

North–South divide in vCJD cases An important change in the rising trend of vCJD cases in Britain has occurred, moving from a flat-line situation to an upward trend over the past year. A total of 106 cases of the fatal brain disease have now been identified, but the new analysis will raise concerns that the number of new cases is accelerating. Existing predictions for the eventual scale of the tragedy range from a few hundred to 140 000. However, James Ironside, at the vCJD Surveillance Unit in Edinburgh, Scotland, UK, has said that because of the uncertainty about the incubation period and not knowing whether everyone is susceptible, it is impossible to say with any certainty what future numbers will be. Ironside also highlighted a dramatic North–South divide in the incidence of cases in the UK, with Scotland and the north

The 1918 influenza pandemic killed 20 million people, yet the reasons behind the deadly nature of the ‘flu virus have been poorly understood. In 1997, American researchers recovered the first genetic evidence of the virus from old samples and the body of a female disease-victim that had been buried in the Alaskan permafrost. Now, researchers from the Australian National University report that recombination between two influenza strains, one of which was probably a swine strain, took place just before the pandemic: the recombined strain might well have caused the deadly outbreak. Investigators from the University of Wisconsin-Madison propose a different explanation for the virulence of the 1997 Hong Kong chicken-‘flu virus: a single amino acid substitution in this virus is enough to make a nonpathogenic strain highly virulent. Avian cases of the virus continue to resurface at poultry markets in Hong Kong. AV 2001-09/nioa-asg083101.php

Global Agenda on Influenza The WHO is developing a Global Agenda on Influenza, which will help set priorities to reduce the morbidity and mortality caused by annual epidemics. The first stage is a call for all those involved in monitoring, treating or studying outbreaks to identify the biggest problems and to propose possible ways to address them. There is a particularly urgent need to tackle ‘flu in developing countries, where it is often not perceived as a major public health problem. Other priority areas include virological and epidemiological surveillance, epidemic and pandemic preparedness, expansion of vaccine use (particularly in developing countries), accelerating the introduction of new vaccines, and understanding the health and economic burdens of influenza. The WHO expects to publish the Global Agenda on Influenza on the internet later in 2001, so that it can be publicly discussed. The Agenda will then be continuously updated to take account of comments and the most recent research. CK

Tuber power Despite the availability of a safe and effective vaccine, hepatitis B remains at epidemic levels in many poor nations, where the costs of the vaccine are prohibitive. The current subunit vaccine is produced in yeast, but a cheaper, oral vaccine could potentially be produced in plants. A team of American researchers recently demonstrated the success of hepatitis B surface antigen produced in potato plants and fed to mice. However, boiling the potatoes reduced the immunogenicity of the antigen. Reporting in PNAS, the study authors suggest that tomatoes or bananas, which are eaten raw by people, might be better candidates as vehicles for the vaccine. The authors also say that an oral HBV vaccine would be more feasible for wide-scale vaccination programs, as it would be more convenient and would get higher patient compliance. AV http://www.pnas.org兾cgi兾doi兾10.1073兾 pnas.191617598

Tackling tough TB Scientists might have discovered a way to combat the emergence of multi-drug resistant TB. Dr Jim Naismith and colleagues at the University of St Andrews, Scotland, UK have established how the bacteria that cause this type of TB produce two essential sugars. They hope to be able to inhibit bacterial growth by targeting new antibiotics against some of the enzymes involved in the synthesis of these sugars. The work is of major importance because, according to Dr Naismith, ‘in the UK, multidrug resistant TB, which is very hard to treat with current medicines, is emerging as a major health problem, and in many developing countries drug tolerant bacteria are endemic’. CK

In Brief compiled by Cathel Kerr ([email protected]) and Alexandra Venter ([email protected])

0966-842X/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.