Abstract There have been few recent studies demonstrating a definitive association between the transmission of airborne infections and the ventilation of buildings. The severe acute respir...

Schistosomiasis is a parasitic-worm infection that affects about 200 million people in 74 countries. Despite major advances in treatment and control, this tropical disease continues to spread to new geographic areas. This review summarizes the manifestations of this disease, its diagnosis, medical treatment, and prophylaxis, and the prospects for a vaccine.

SUMMARY: Ross River virus (RRV) is a fascinating, important arbovirus that is endemic and enzootic in Australia and Papua New Guinea and was epidemic in the South Pacific in 1979 and 1980. Infection with RRV may cause disease in humans, typically presenting as peripheral polyarthralgia or arthritis, sometimes with fever and rash. RRV disease notifications in Australia average 5,000 per year. The first well-described outbreak occurred in 1928. During World War II there were more outbreaks, and the name epidemic polyarthritis was applied. During a 1956 outbreak, epidemic polyarthritis was linked serologically to a group A arbovirus (Alphavirus). The virus was subsequently isolated from Aedes vigilax mosquitoes in 1963 and then from epidemic polyarthritis patients. We review the literature on the evolutionary biology of RRV, immune response to infection, pathogenesis, serologic diagnosis, disease manifestations, the extraordinary variety of vertebrate hosts, mosquito vectors, and transmission cycles, antibody prevalence, epidemiology of asymptomatic and symptomatic human infection, infection risks, and public health impact. RRV arthritis is due to joint infection, and treatment is currently based on empirical anti-inflammatory regimens. Further research on pathogenesis may improve understanding of the natural history of this disease and lead to new treatment strategies. The burden of morbidity is considerable, and the virus could spread to other countries. To justify and design preventive programs, we need accurate data on economic costs and better understanding of transmission and behavioral and environmental risks.

SUMMARY: Schistosomiasis japonica is a serious communicable disease and a major disease risk for more than 30 million people living in the tropical and subtropical zones of China. Infection remains a major public health concern despite 45 years of intensive control efforts. It is estimated that 865,000 people and 100,250 bovines are today infected in the provinces where the disease is endemic, and its transmission continues. Unlike the other schistosome species known to infect humans, the oriental schistosome, Schistosoma japonicum, is a true zoonotic organism, with a range of mammalian reservoirs, making control efforts extremely difficult. Clinical features of schistosomiasis range from fever, headache, and lethargy to severe fibro-obstructive pathology leading to portal hypertension, ascites, and hepatosplenomegaly, which can cause premature death. Infected children are stunted and have cognitive defects impairing memory and learning ability. Current control programs are heavily based on community chemotherapy with a single dose of the drug praziquantel, but vaccines (for use in bovines and humans) in combination with other control strategies are needed to make elimination of the disease possible. In this article, we provide an overview of the biology, epidemiology, clinical features, and prospects for control of oriental schistosomiasis in the People's Republic of China.

Large dams have been an important component of infrastructure development in capitalist and communist countries alike. In 1998, changing world attitudes on large dams led to a two year World Commission on Dams and new global standards may soon insist that future projects pay fair compensation so that resettlement becomes voluntary. Now, 10 years after introduction of economic reforms, China is mobilizing its resources to build the world's largest dam. This fulfils a longstanding ambition to impound the Yangtze River in Central China at the Three Gorges and use the hydropower, improved navigation and flood control to develop the economy. This paper examines the socio-economic impact of Three Gorges Dam on over 1.3 million people to be displaced while China is in transition to a market economy. We consider resettlement in terms of the decision-making structure, property rights and incentives to move, and how the project exacerbates problems created by market reforms, especially rising unemployment and deteriorating public health. We conclude the project is boosting economic expectations while adversely affecting large sections of the population, and this could provoke widespread social unrest and eventual changes in political institutions.