What is the relationship between greenhouse effect and infectious diseases?

Two Swedish medical researchers recently pointed out through investigation that global warming caused by the greenhouse effect is leading to a sharp increase in infectious diseases.

According to the Swedish News Agency, Lindegren of Stockholm University and gustafson of Karolinska Medical College in Sweden came to this conclusion when investigating the incidence of tick-borne meningitis in Stockholm. They found that in the late 1970s, only about 65,438+00 people per million people in Stockholm were infected with tick meningitis every year, but by the 1990s, this number had increased to about 30 people.

They think that in recent 20 years, global warming caused by the greenhouse effect has made ticks, the vectors of tick meningitis, increase rapidly in Stockholm. For example, in the past 10 years, the increase rate reached 16%. In addition, in the northern coastal areas of Sweden, ticks rarely seen in the past have increased by 40% in the past 10 years.

The human body is very sensitive and fragile to the degree and speed of climate change, and the SARS that once spread may be related to climate change.

The direct impact of climate change on health comes from temperature, extreme weather and sea level rise. The change of rainfall and temperature may disturb the natural ecosystem, change the ecological environment of infectious diseases, destroy the supply of agriculture and fresh water, aggravate air pollution and cause large-scale reorganization of animal and plant communities. These indirect factors have a greater cumulative impact on human health.

The World Health Organization points out that if countries around the world can't take effective measures to ensure the normal global climate, by 2020, 700,000 people will die every year.

The people who are most sensitive to global warming are those who live in the middle latitudes. Long-term heat and high temperature and humidity will lead to diseases or deaths mainly in the heart and respiratory system. Continuous high temperature has a greater impact on mortality than instantaneous high temperature. Due to the "heat island effect", the temperature in the urban area is not only high but also lasts for a long time, and the heat wave is associated with high pollution level. Therefore, the warming of temperature provides a more suitable hotbed for the reproduction and spread of many diseases. For example, in new york and Shanghai, once the temperature exceeds a certain threshold, the daily mortality rate will increase significantly. 1The heat wave in Chicago in July 1995 killed 726 people in four days.

In human history, several uncontrollable plagues broke out, which quickly changed the history of human civilization. Although the spread of diseases is related to population growth and urbanization, the rapidly warming climate may become a stimulating factor for the global spread of diseases. Climate warming will change the boundaries of climatic zones, which will provide a broader space for many "thermophilic bacteria" to survive and move. In addition, climate change can also affect the incidence rate through various channels.

Under the combined action of environmental and social pressures, global warming will affect the effect of disease control. At present, the trend of global warming makes millions of people face many new diseases. Once an alien infectious disease is introduced into a certain place, it is almost impossible to completely eliminate it.

During the SARS period, the World Health Organization 1996 reported that at least 30 new infectious diseases appeared in the past 20 years. Dengue fever, a traditional infectious disease, disappeared in the western hemisphere, but now it has spread in the United States. Malaria is actually prevalent in the Central African Plateau. The resurgence of malaria, dengue fever and cholera and the emergence of new infectious diseases around the world have affected the health of all mankind and the development of international trade, tourism and agricultural economy. 199 1 year, Peru lost 1 billion dollars in seafood export and tourism due to cholera epidemic. India's aviation industry and hotel industry lost $2 billion due to 1994 plague epidemic. Cruise ships dare not approach Caribbean countries ravaged by dengue fever, resulting in a loss of income of 654.38+0.2 billion US dollars, and 500,000 employees in the tourism industry are unemployed.

Some scientists have warned that due to the melting of Arctic ice due to global temperature rise, the former deadly virus that has been frozen for more than 10 million years may reappear, leading to global epidemic panic and seriously threatening human life.

According to the news disclosed by the Russian Pravda, 1999, a scientific expedition discovered an unprecedented "mysterious virus" on the permafrost of the Antarctic continent, and neither humans nor animals have enough immunity to it. Because the virus "sleeps" at the bottom of Antarctic permafrost, it will not pose a threat to human beings on earth for the time being. However, American scientists have warned that if the global climate continues to warm to a certain extent, this unknown virus may resurface and spread everywhere. At that time, thousands of species on the earth will face extinction.

This new discovery makes researchers believe that a series of epidemic viruses such as influenza, polio and smallpox may be hidden deep in the ice. At present, human beings have no resistance to these primitive viruses. When the global temperature rises and the ice melts, these viruses buried in the ice for thousands of years or more may resurface and form an epidemic. Scientists say that although they don't know the survival hope of these viruses or the chance to adapt to the ground environment again, they certainly can't deny the possibility of the virus coming back.