Rush was one of the founding fathers of the United States who signed the Declaration of Independence. A few years later, during the yellow fever epidemic in Philadelphia, he treated many people, including himself, with bloodletting therapy, which caused more harm than reputation. Rush was also the founder of psychiatry. From him, mental illness is regarded as a disease, not a heresy.
The cause of dengue fever and its transmission route were not fully understood until the 20th century, and its transmission route was determined at 1906. Dengue fever became the second viral disease in 1907. Like malaria and yellow fever, this disease is spread by mosquitoes. Dengue virus (DENV) is an RNA virus that has existed for a long time, but it did not exist in wild animals until hundreds of years ago, that is, it spread between Aedes mosquitoes and primates and occasionally caused human diseases. But later it became a cycle between Aedes mosquitoes and humans, and dengue fever became a real human disease. There are many such examples, and Ebola is one example. At present, Ebola is still in its host and primates, and has not really entered humans, but this threat is real.
The rapid increase of dengue fever is due to the large-scale population movement during World War II. Now it is a common disease in 1 10 countries around the world. More than 50 million to 500 million people are infected every year in the world, resulting in 500,000 hospitalizations and 25,000 deaths. Among them, there are 3 million people infected in South Asia 12 countries, and 6000 people die every year. In Africa, 20% of the population is threatened by dengue fever.
In the past half century, the number of cases of dengue fever has increased 30 times. There are several possible reasons for the rapid growth of dengue fever, including rapid onset in suburbs and insufficient drainage system; Mosquito breeding grounds are not well controlled; Climate change and virus evolution; The increase of international travel and so on. It is precisely because there are so many factors that it is relatively difficult to control dengue fever. At present, 2.5 billion people live in dengue endemic areas, 70% of which are in the Asia-Pacific region, making dengue fever an insect-borne infectious disease second only to malaria and a serious epidemic disease in Asia.
The mortality rate of dengue patients is 1% to 5%. Most people have mild symptoms and heal themselves in about a week. Mild symptoms include high fever, headache, rash, muscle pain and joint pain. The serious symptom is dengue hemorrhagic fever, which makes blood pressure drop sharply and may lead to death.
These symptoms and other diseases are also possible. How can we be sure it's dengue fever?
You don't have to be sure. If you have been to an endemic area of dengue fever and these symptoms suddenly appear, you should see a doctor. If the symptoms are mild as mentioned above, you don't need to do special virus detection and analysis, because when the results come out, you may have recovered or been very bad.
There are four types of dengue virus. After infection, you will be immune to this virus for life and temporarily immune to other viruses, so you may get dengue fever up to four times. This repeated infection is prone to hemorrhagic fever.
Because there is no specific medicine, the key is to keep the liquid balance. If you can drink water, urinate, have mild symptoms and have no other problems, take some painkillers and go home and bear it. Severe patients should be hospitalized to support treatment, infusion and blood transfusion if they lose blood seriously.
There are several kinds of dengue vaccines in clinical trials, one of which has just completed the third phase of clinical trials, with good safety and poor effectiveness. In clinical trials in Thailand, the effective rate is only 30.2%, and the last 56%. The effective rates against virus IV were 54.5%, 34.7%, 65.2% and 72.4% respectively, and the preventive ability against dengue II was the worst. The other study was only 60%, which is still the worst for type 2. But vaccines can reduce serious cases by 80%.
In this case, the key to prevent dengue fever lies in mosquitoes, so don't be bitten by mosquitoes. To control Aedes mosquitoes by eliminating breeding grounds, we must first try to ensure that there is no open water source. If this is not possible, add pesticides to the water. The former is really difficult to do, and the latter has great health risks. Half a century ago, the global anti-mosquito campaign ended in failure, and the impact of DDT on ecology still exists today.
In this case, personal measures should be taken to prevent dengue fever. First of all, don't go to dengue endemic areas, which is not easy, and many people live in dengue endemic areas, including many areas in southern China. In this way, you should wear long clothes and long sleeves, and you should not expose your skin. You should use screen mosquito nets or mosquito repellent to rest and sleep.
However, these methods are not effective at present, and due to the influence of climate change, dengue fever will continue to rise, which is one of the serious health challenges facing mankind today and in the future.