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AIDS analysts concerned by trends
News & Comment
HIV/AIDS analysts concerned by trends Thanks to new therapies – for those who can afford them – fewer cases of HIV are progressing to AIDS. However, the rate of new HIV infections is increasing in some populations. Studies indicate that in Canada and the United States, the HIV incidence in young gay and bisexual men is once again on the rise. Health Canada reports that the epidemic among heterosexual Canadians has also been creeping upwards. Indigenous Canadians are disproportionately affected; they comprise only 2.8% of the population but accounted for 15% of AIDS cases in Canada in 1999. At the recent United Nations Special Session on HIV/AIDS, UN Secretary General Kofi Annan stated that the AIDS pandemic is ‘a human tragedy of unimaginable proportions’ and that all those affected by the disease deserve humane treatment, regardless of their religious beliefs or orientation. AV http://www.hc-sc.gc.ca/english/magazine/ 2000_11/aids.htm http://www.cdc.gov/od/oc/media/pressrel/ r010601.htm http://www.un.org/ga/aids/press.htm
Fast TB test A quick blood test that can accurately detect tuberculosis infection before symptoms appear has been developed by a British team. The test could be used to screen people during a disease outbreak, allowing drugs to be given to infected individuals as early as possible, says researcher Ajit Lalvani of Oxford University. This would improve the containment of an outbreak. The conventional TB test dates back 100 years and involves injecting a mixture of >200 proteins. However, these proteins are present in Mycobacterium tuberculosis, the anti-TB BCG vaccine as well as other bacteria. This means the test often gives false-positive results for people who have had the BCG vaccination. Lalvani’s test looks for immune system T cells responding to ESAT-6, a protein present in M. tuberculosis, but absent from the BCG vaccine. CK http://www.newscientist.com/news http://tim.trends.com
TRENDS in Microbiology Vol.9 No.8 August 2001
Clues to malaria immunity Malarial immunity shown by Ghanaian children in a recent study could aid researchers in the development of an effective vaccine. In the study published in June in Infection and Immunity, the children were screened for antibodies to Plasmodium falciparum and antigens on infected erythrocytes. Children with higher levels of antibodies directed against antigens on infected cells were less likely to contract malaria during the subsequent malaria season. The WHO estimates that, had malaria been eliminated from Africa years ago, Africa’s GDP would now be increased by $100 billion. AV http://www.who.int/inf-fs/en/back001.html http://www.asmusa.org/pcsrc/tip0601c.htm
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sequenced strain participated in a previous gene transfer that changed the outer macromolecular capsule, disguising the bacterium from the host immune system. The authors also identified >47 whole or fragmented transposases, or genetic elements that can allow the bacterium to reshuffle the DNA within chromosomes. It is thought that these could explain why the genetic and physical map of this strain is so different from other studied laboratory strains. S. pneumoniae is still a major worldwide pathogen, with the estimated deaths from pneumonia totalling 3.5 million in 1998. CK http://www.mediscover.net/brknews2.cfm
Mutual satisfaction
Intradermal hep B vaccine An intradermal hepatitis B vaccine is as effective, and at least 80% less expensive, than the conventional intramuscular vaccine, according to the results of a study conducted in Iran. The team from Shiraz University of Medical Sciences in Teheran studied 165 neonates; 82 were given 2 µg of recombinant hepatitis B vaccine intradermally, and the control group received the recommended 10 µg intramuscularly. The same schedule of 3 doses was followed in both groups. Although the antibody titre was significantly lower at 6 months in the intradermal group, the difference was no longer significant at 18 months, suggesting that the antibody rise might be more gradual with intradermal vaccination. Even at 6 months, 81.7% of the children in the intradermal group had antibody titres that exceeded the minimum effective level. As the intradermal vaccine uses only 20% of the conventional intramuscular dose, it is more economical. CK http://id.medscape.com/38683.rhtml?srcmp =id-060801
S. pneumoniae genome: closure beckons More than 90% of the genome of the macrolide- and tetracycline-resistant Streptococcus pneumoniae type 19F has been sequenced, according to a report in Microbial Drug Resistance. The genetic data give a unique insight into the molecular events responsible for resistance. It is suggested that the
It is hoped that recent studies of prokaryote–eukaryote symbiosis will contribute to medical research. Newly determined evolutionary relationships in fungi indicate that a number of nonlichen-forming fungi, including human pathogens, have lichen-forming ancestors. Comparisons between these and non-lichen formers of separate lineage could shed some light on fungal diseases. Also of interest is the close association between one strain of bacteria and a sea-sponge living in Australia’s Great Barrier Reef. Bioactive compounds derived from sea sponges or associated bacteria are being investigated as potential new drugs. A better understanding of the symbiotic association is considered an important first step in studying these compounds. Researchers from the University of Maryland Biotechnology Institute and Australian Institute of Marine Science say that the presence of the bacteria might indicate the state of health of the Rhopaloeides odorabile sponge: some unhealthy specimens of this sponge did not harbour the bacterial strain. AV http://www.nsf.gov/od/lpa/news/press/01/ pr0152.htm http://www.eurekalert.org/bysubject.php? kw=104
0966-842X/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.
HIV/AIDS analysts concerned by trends Thanks to new therapies – for those who can afford them – fewer cases of HIV are progressing to AIDS. However, the rate of new HIV infections is increasing in some populations. Studies indicate that in Canada and the United States, the HIV incidence in young gay and bisexual men is once again on the rise. Health Canada reports that the epidemic among heterosexual Canadians has also been creeping upwards. Indigenous Canadians are disproportionately affected; they comprise only 2.8% of the population but accounted for 15% of AIDS cases in Canada in 1999. At the recent United Nations Special Session on HIV/AIDS, UN Secretary General Kofi Annan stated that the AIDS pandemic is ‘a human tragedy of unimaginable proportions’ and that all those affected by the disease deserve humane treatment, regardless of their religious beliefs or orientation. AV http://www.hc-sc.gc.ca/english/magazine/ 2000_11/aids.htm http://www.cdc.gov/od/oc/media/pressrel/ r010601.htm http://www.un.org/ga/aids/press.htm
Fast TB test A quick blood test that can accurately detect tuberculosis infection before symptoms appear has been developed by a British team. The test could be used to screen people during a disease outbreak, allowing drugs to be given to infected individuals as early as possible, says researcher Ajit Lalvani of Oxford University. This would improve the containment of an outbreak. The conventional TB test dates back 100 years and involves injecting a mixture of >200 proteins. However, these proteins are present in Mycobacterium tuberculosis, the anti-TB BCG vaccine as well as other bacteria. This means the test often gives false-positive results for people who have had the BCG vaccination. Lalvani’s test looks for immune system T cells responding to ESAT-6, a protein present in M. tuberculosis, but absent from the BCG vaccine. CK http://www.newscientist.com/news http://tim.trends.com
TRENDS in Microbiology Vol.9 No.8 August 2001
Clues to malaria immunity Malarial immunity shown by Ghanaian children in a recent study could aid researchers in the development of an effective vaccine. In the study published in June in Infection and Immunity, the children were screened for antibodies to Plasmodium falciparum and antigens on infected erythrocytes. Children with higher levels of antibodies directed against antigens on infected cells were less likely to contract malaria during the subsequent malaria season. The WHO estimates that, had malaria been eliminated from Africa years ago, Africa’s GDP would now be increased by $100 billion. AV http://www.who.int/inf-fs/en/back001.html http://www.asmusa.org/pcsrc/tip0601c.htm
363
sequenced strain participated in a previous gene transfer that changed the outer macromolecular capsule, disguising the bacterium from the host immune system. The authors also identified >47 whole or fragmented transposases, or genetic elements that can allow the bacterium to reshuffle the DNA within chromosomes. It is thought that these could explain why the genetic and physical map of this strain is so different from other studied laboratory strains. S. pneumoniae is still a major worldwide pathogen, with the estimated deaths from pneumonia totalling 3.5 million in 1998. CK http://www.mediscover.net/brknews2.cfm
Mutual satisfaction
Intradermal hep B vaccine An intradermal hepatitis B vaccine is as effective, and at least 80% less expensive, than the conventional intramuscular vaccine, according to the results of a study conducted in Iran. The team from Shiraz University of Medical Sciences in Teheran studied 165 neonates; 82 were given 2 µg of recombinant hepatitis B vaccine intradermally, and the control group received the recommended 10 µg intramuscularly. The same schedule of 3 doses was followed in both groups. Although the antibody titre was significantly lower at 6 months in the intradermal group, the difference was no longer significant at 18 months, suggesting that the antibody rise might be more gradual with intradermal vaccination. Even at 6 months, 81.7% of the children in the intradermal group had antibody titres that exceeded the minimum effective level. As the intradermal vaccine uses only 20% of the conventional intramuscular dose, it is more economical. CK http://id.medscape.com/38683.rhtml?srcmp =id-060801
S. pneumoniae genome: closure beckons More than 90% of the genome of the macrolide- and tetracycline-resistant Streptococcus pneumoniae type 19F has been sequenced, according to a report in Microbial Drug Resistance. The genetic data give a unique insight into the molecular events responsible for resistance. It is suggested that the
It is hoped that recent studies of prokaryote–eukaryote symbiosis will contribute to medical research. Newly determined evolutionary relationships in fungi indicate that a number of nonlichen-forming fungi, including human pathogens, have lichen-forming ancestors. Comparisons between these and non-lichen formers of separate lineage could shed some light on fungal diseases. Also of interest is the close association between one strain of bacteria and a sea-sponge living in Australia’s Great Barrier Reef. Bioactive compounds derived from sea sponges or associated bacteria are being investigated as potential new drugs. A better understanding of the symbiotic association is considered an important first step in studying these compounds. Researchers from the University of Maryland Biotechnology Institute and Australian Institute of Marine Science say that the presence of the bacteria might indicate the state of health of the Rhopaloeides odorabile sponge: some unhealthy specimens of this sponge did not harbour the bacterial strain. AV http://www.nsf.gov/od/lpa/news/press/01/ pr0152.htm http://www.eurekalert.org/bysubject.php? kw=104
0966-842X/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.