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Hantavirus disease emerging
and with antisense oligonucleotides to lysis in MI), hirudin produced better inhibit cell proliferation. coronary patency rates, significantly Research into the management of reduced deaths, and led to fewer patients with heart failure has moved revascularisation procedures, comaway from optimising haemodynamic ‘ pared with heparin. In addition, data variables-contractility, preload, and from TIMI-7 show that hirulog is effective in the treatment of unstable after-load-to modification of factors that might initiate failure. There is evangina. The UK Oxford Clinical Trialists idence suggesting that the activation for stents was also significantly of the sympathetic nervous system Group will shortly start to compare smaller at one year. The need for and the renin-angiotensin system the effect on cholesterol of simvastatin and a combination of antiintensive heparinisation limits wider causes heart failure. Treatments to attenuate this neuroendocrine drive are oxidants (vitamins C and E, betaapplication of this technique. Another approach is to target the now receiving substantial attention. carotene) with placebo. 20 000 final common pathway of thrombosuch as For example, beta-blockers patients at high risk of heart disease sis-platelet activation-with glyco- carvedilol, which has beta-blocker or who have already had an MI will be enrolled. One-third of patients will and vasodilator activity, reverse symprotein IIa/IIIb inhibitors. Activation and of platelet IIa/IIIb receptors causes parasympathetic changes be women and one-third will be pathetic found in heart failure and improve elderly, permitting multiple comparbinding of platelet to circulating fibleft ventricular function. isons of treatment efficacy. The prorinogen and platelet aggregation. The future? Studies of all trial data on two Early receptor antagcoronary tocol for ISIS-5 has yet to be written are to onists are encouraging. The third apfocus on two but may include a thrombin inhibitor, syndromes likely new groups of agents: thrombin ina beta blocker, or a new plasminogen proach is to reduce the intimal hibitors and glycoprotein IIa/IIIb activator. proliferation that forms part of the healing response in angioplasty-eg, antagonists. Hirudin and hirulog are with fusion toxins directed against specific antithrombins which, unlike growth factor receptors expressed on heparin, do not require antithrombin III. In the TIMI-5 trial (thromboRichard Horton the vascular smooth muscle cell wall,
However, in 30-50% of angioplasty1 patients restenosis occurs. ; One approach to avoiding this complication is the use of coronary endovascular stents. In the stent restenosis (STRESS) trial and the Benestent study lumen diameter was significantly greater with a stent than with angioplasty; the restenosis rate
Hantavirus disease
emerging
The idea that infectious disease is in decline is having to be abandoned as unprecedented social and ecological changes increase the likelihood of previously unidentified diseases appearing and of old ones in resurgence. An international multidisciplinary conference at Woods Hole, v Massachusetts, last week, organised by the Harvard School of Public Health’s Working Group on New and Resurgent Disease, saw the beginnings of a new conceptual framework and a comparative approach to research and surveillance. The 50 participants, including specialists in epidemiology, ecology, and animal and ’ ., plant disease, came from research institutes, the World Health Organization, the US Centers for Disease Control and Prevention (CDC), and the US National Oceanic and Atmospheric Administration. Specific diseases illustrated the range and diversity of issueseg, cholera and new vibrio variants, seafood biotoxins, malaria, Venezuelan haemorrhagic fever, dengue fever, bean golden mosaic virus disease, and hantavirus infection. CDC (Oct 29) confirms 42 cases of hantavirus infection in twelve US states, with 26 deaths (62%). The startling appearance of a lethal presentation (hantavirus pulmonary syndrome) by viruses perhaps at low-level persistence in rodent populations raises important questions. Is the extreme virulence the sign of a novel
1292
variant? Did changes in rodent reservoir ecology amplify the viral agent and help to select a highly dangerous mutation? Hantaviruses have previously been associated with haemorrhagic fever with renal syndrome and possibly chronic nephropathy. The US south-west, desiccated
through overgrazing and impoverishment of local populations, sustained six years of drought succeeded by heavy rains. Pinon flourished and rodents prospered and proliferated. There was a ten-fold increase in rodents between May, 1992, and May of this year.’ The primary rodent reservoir (Peromyscus maniculatus) is abundant in North America save for the south-east. Periodic reports from Europe of new hantavirus isolates and new cases point to other hantaviruses in geographically isolated rodent populations. The identification of Puumala virus in wild Mus musculus (house mouse) in Yugoslavia= suggests the possibility of transfer of hantaviruses among different rodent species. Former Yugoslavia is a critical region here, its ecology having been disrupted by war and economic breakdown. Expanded surveillance of new clinical entities, known vectors, and pathogen reservoirs is needed. Rodents, for example, harbour several agents, and rural and urban numbers reflect defective natural controls. A database for systematic epi-
nuts
demiology is needed
to
explore questions
such as-how do cellular nutrients and chemicals influence gene expression and selection; how do increased recombination opportunities or mutation-promoting environments affect parasite adaptation to new conditions; which parasites can invade hosts of broad taxonomic range and which are restricted to just a few genera; do parasites with broad host ranges produce more or less virulent disease; and what is the relation between clinical aspects of a disease and the darwinian fitness of the parasite (for instance whether pulmonary infections are less speciesspecific than gastrointestinal infections)? Integration of research, monitoring, and management, based on systems approaches, can best ensure that untoward indirect effects of interventions do not overwhelm intended effects, the conference concluded. The proceedings of the conference will be published by the New York Academy of Science. Support for the conference was provided by the John D & Catherine MacArthur Foundation and the Rockefeller Foundation.
Richard Levins, Paul R Epstein, Mary E Wilson, Stephen S Morse, Rudi Slooff, Irina Eckardt 1 Marshall 2
E, Stone R. Hantavirus outbreak yields to PCR. Science 1993; 262: 832-36. Diglisic G, et al. Isolation of a Puumala-like virus from Mus musculus captured in Yugoslavia and its association with severe hemorrhagic fever with renal syndrome. J Infect Dis (in press).
However, in 30-50% of angioplasty1 patients restenosis occurs. ; One approach to avoiding this complication is the use of coronary endovascular stents. In the stent restenosis (STRESS) trial and the Benestent study lumen diameter was significantly greater with a stent than with angioplasty; the restenosis rate
Hantavirus disease
emerging
The idea that infectious disease is in decline is having to be abandoned as unprecedented social and ecological changes increase the likelihood of previously unidentified diseases appearing and of old ones in resurgence. An international multidisciplinary conference at Woods Hole, v Massachusetts, last week, organised by the Harvard School of Public Health’s Working Group on New and Resurgent Disease, saw the beginnings of a new conceptual framework and a comparative approach to research and surveillance. The 50 participants, including specialists in epidemiology, ecology, and animal and ’ ., plant disease, came from research institutes, the World Health Organization, the US Centers for Disease Control and Prevention (CDC), and the US National Oceanic and Atmospheric Administration. Specific diseases illustrated the range and diversity of issueseg, cholera and new vibrio variants, seafood biotoxins, malaria, Venezuelan haemorrhagic fever, dengue fever, bean golden mosaic virus disease, and hantavirus infection. CDC (Oct 29) confirms 42 cases of hantavirus infection in twelve US states, with 26 deaths (62%). The startling appearance of a lethal presentation (hantavirus pulmonary syndrome) by viruses perhaps at low-level persistence in rodent populations raises important questions. Is the extreme virulence the sign of a novel
1292
variant? Did changes in rodent reservoir ecology amplify the viral agent and help to select a highly dangerous mutation? Hantaviruses have previously been associated with haemorrhagic fever with renal syndrome and possibly chronic nephropathy. The US south-west, desiccated
through overgrazing and impoverishment of local populations, sustained six years of drought succeeded by heavy rains. Pinon flourished and rodents prospered and proliferated. There was a ten-fold increase in rodents between May, 1992, and May of this year.’ The primary rodent reservoir (Peromyscus maniculatus) is abundant in North America save for the south-east. Periodic reports from Europe of new hantavirus isolates and new cases point to other hantaviruses in geographically isolated rodent populations. The identification of Puumala virus in wild Mus musculus (house mouse) in Yugoslavia= suggests the possibility of transfer of hantaviruses among different rodent species. Former Yugoslavia is a critical region here, its ecology having been disrupted by war and economic breakdown. Expanded surveillance of new clinical entities, known vectors, and pathogen reservoirs is needed. Rodents, for example, harbour several agents, and rural and urban numbers reflect defective natural controls. A database for systematic epi-
nuts
demiology is needed
to
explore questions
such as-how do cellular nutrients and chemicals influence gene expression and selection; how do increased recombination opportunities or mutation-promoting environments affect parasite adaptation to new conditions; which parasites can invade hosts of broad taxonomic range and which are restricted to just a few genera; do parasites with broad host ranges produce more or less virulent disease; and what is the relation between clinical aspects of a disease and the darwinian fitness of the parasite (for instance whether pulmonary infections are less speciesspecific than gastrointestinal infections)? Integration of research, monitoring, and management, based on systems approaches, can best ensure that untoward indirect effects of interventions do not overwhelm intended effects, the conference concluded. The proceedings of the conference will be published by the New York Academy of Science. Support for the conference was provided by the John D & Catherine MacArthur Foundation and the Rockefeller Foundation.
Richard Levins, Paul R Epstein, Mary E Wilson, Stephen S Morse, Rudi Slooff, Irina Eckardt 1 Marshall 2
E, Stone R. Hantavirus outbreak yields to PCR. Science 1993; 262: 832-36. Diglisic G, et al. Isolation of a Puumala-like virus from Mus musculus captured in Yugoslavia and its association with severe hemorrhagic fever with renal syndrome. J Infect Dis (in press).