1. 1 concept
Influenza is caused by human influenza virus. There are three types of human influenza virus: type A virus, which is the most dangerous and common virus found in wild birds, poultry, pigs, whales, horses and seals. The subtype of type A virus is determined according to the H and N proteins on the virus surface. B virus may also cause an epidemic. But it only spreads from person to person; Type C virus is the least harmful, it can cause mild respiratory diseases, but it will not cause epidemics.
Avian influenza is an infectious disease of avian influenza virus. Influenza spread among birds is mainly influenza A. All birds are susceptible to this virus. Avian influenza virus can be divided into H 15 subtypes according to the different hemagglutinin on its surface, such as H 1 to h 15, among which H5 and H7 are the most deadly subtypes to poultry, and the morbidity and mortality can reach 100%. These two subtypes can also be transmitted to people. The main symptoms of avian influenza are high fever, cough, runny nose and myalgia. Most of them are accompanied by severe pneumonia, and severe cardiac and renal failure leads to death, with a high mortality rate. The disease can be transmitted through digestive tract, respiratory tract, skin injury and conjunctiva, and traffic between people and vehicles is an important factor to spread the disease. The main infection in China is H5N 1 virus.
The World Health Organization (WHO) calls "SARS" severe acute respiratory syndrome. Scientists named the new variant coronavirus that caused SARS "SARS virus". SARS virus is related to influenza virus, but it is very unique and has never been found in humans before.
Differences between influenza and avian influenza
Influenza A is mostly avian influenza, and avian influenza virus rarely makes people sick. Avian influenza mainly spreads among birds and occasionally infects people. Its clinical manifestations are similar to human influenza, but human avian influenza has severe symptoms, many complications, high mortality and ineffective vaccination, which is different from ordinary influenza.
1.3 the relationship between avian influenza and other animal influenza
Because of the small interspecific difference between pigs and humans, avian influenza virus can cross with human influenza virus in the intermediate host (pig) to produce a new type of influenza virus that can infect humans.
1.4 the difference between avian influenza and SARS
SARS is caused by a kind of novel coronavirus. Coronavirus belongs to Coronaviridae, and avian influenza virus belongs to orthomyxoviridae, which are completely different viruses. Generally speaking, the onset of SARS patients is similar to the clinical manifestations of avian influenza, especially the early manifestations, such as fever, dry cough, less sputum, fatigue, diarrhea and so on. Therefore, we should pay attention to the distinction from SARS, and the most reliable method is DNA probe.
1.5 The probability of human infection with avian influenza is very small.
There are three reasons: ① Avian influenza virus is not easy to be recognized and combined by human cells. ② The genomes of all influenza viruses that can spread among people must contain several gene fragments of human influenza virus, but avian influenza virus does not. ③ Highly pathogenic avian influenza virus contains a lot of basic amino acids, so it is difficult to replicate in human body.
2. Experience the harm of avian influenza from the time when human influenza is prevalent.
/kloc-the worldwide influenza pandemic in 0/00 may all be related to avian influenza. As can be seen from the table, wild birds, poultry and livestock have played a role in spreading the new influenza virus to people.
Table 1
time
19 18
1957
1968
1977
1997
1999
2003-present
The new influenza virus type of that year
H 1N 1
H2N2
H3N2
H 1N 1
H5N 1
H9N2
H5N 1 H7N7
Animals that spread new viruses to humans.
Pigs, migratory birds, etc
Migratory birds, etc
Pigs, migratory birds, etc
Pigs, migratory birds, etc
Chickens, ducks, pigs, migratory birds, etc.
Chicken, pig, bird, etc.
Chicken, pig, bird, etc.
The above data are taken from the weekend science edition of Nanfang Daily on February 5, 2004. ※.
3. Compare influenza, avian influenza and SARS from epidemiology and serology.
Table 2
Comparison project
flu
Highly pathogenic avian influenza (HPAI)
"SARS"
full name
flu
avian influenza
Severe acute respiratory syndrome (SARS)
pathogen
ribonucleic acid virus
ribonucleic acid virus
ribonucleic acid virus
Main host
People, wild birds, poultry, pigs, etc.
Chickens, ducks, migratory birds, etc.
People, civets, etc.
Transmission routing
Air water droplets
Air droplets, feces, etc.
Air droplets and close contact
Main parasitic site
Respiratory mucosa and lung
Respiratory mucosa and lung
Respiratory mucosa and lung
harm
Most can heal themselves.
High fever, pneumonia, respiratory failure and other organs, and even death.
Acute onset, rapid spread, high mortality, no specific drugs for the time being.
The most reliable detection method
DNA probe and antibody-antigen reaction in serology
DNA probe and antibody-antigen reaction in serology
DNA probe and antibody-antigen reaction in serology
In a word, bird flu may exist more widely in the environment and do more harm to animal husbandry, but its harm to people is far less serious than that of SARS, and people's research on bird flu is more in-depth.
4. Predict the direction of college entrance examination proposition.
Question 1 This spring, a 35-year-old man was infected with the pathogen of SARS. The following table shows the changes of body temperature and corresponding antibody levels of infected people during the two-week infection period. Please answer this question:
Table 3
date
sun
one
two
three
four
five
six
sun
one
two
three
four
five
six
temperature
37
37
36.9
36.8
36.5
37
37.5
38.5
39.5
39.0
37
37
36.9
37
Antibody level
not have
not have
not have
not have
not have
low
low
middle
high
high
middle
low
low
low
(1) coronavirus and human cells * * * Some compounds are protein, which can infect human body and cell surface.
Related to the recognition function.
(2) When coronavirus replicates, it destroys tissues and cells. What is the reason why its inheritance does not follow Mendel's law?
(3) This virus is parasitic in some animals, but the animals are not sick. This mechanism is worth studying. According to this answer: What is the value of wild animals as an important part of biodiversity?
(4) This person is infected with the pathogen of SARS, but he can survive. Can the antibodies produced in the body be sure to avoid reinfection?
The reason is.
(5) Scientists from China Infectious Disease Control Center have prepared a DNA probe kit using the genome of the detected SARS pathogen, which can quickly detect whether the patient is infected with the SARS pathogen. The diagnosis principle is as follows.
(6) Judging from the infectious process of SARS, the infectivity of SARS patients is mainly in the early stage.
Answer to the question 1: (1)RNA glycoprotein (sugar coating) (2) Coronavirus is a cell-free organism (that is, it has no process of sexual reproduction and meiosis) (3) it has direct use value (scientific research value) (4) it may not be immune to the same SARS virus again in a short time; If after a long time, because the single-stranded RNA of the virus is unstable and easy to mutate, the SARS virus that will be reinfected in the future may have mutated, and the specific antibody produced in the original body will be useless and will be infected. (5) Single-stranded DNA reverse transcribed from SARS RNA is complementary to unknown RNA, which means that unknown RNA is SARS. (6) Acute phase (early onset), especially at onset.
Question 2 Injection can prevent some infectious diseases, and the organelle most related to this immunity is A ..
A. ribosomes and mitochondria B. mitochondria and golgi apparatus C. endoplasmic reticulum and centrosome D. chromosomes and ribosomes
Question 3: what is wrong with the understanding of immunity is D.
A. it is a protective physiological function of the body. B. Through immunization, the body can recognize "self" and eliminate "non-self" to maintain internal environment balance and stability. C. it can be divided into nonspecific immunity and specific immunity. D. immune response is good for the body.
Question 4: Antibodies cannot be distributed in C.
A. Serum B. Tissue fluid and lymph C. Urine D. Saliva and milk
Question 5 According to the research, there are many types of variation of SARS virus, and the variation form of HIV is about 100, and the fundamental reason why SARS and HIV can form more different types of variation is A.
A. Gene mutation B. Gene recombination C. Environmental change D. Struggle for survival
From the end of 2002 to the beginning of 2003, an unforgettable cold current-atypical pneumonia struck. ...
Materials 1, Xinhua News Agency February 18 With the joint efforts of China Center for Disease Control and Prevention and Guangdong Center for Disease Control and Prevention, the pathogen causing SARS in some areas of Guangdong Province can basically be identified as chlamydia. It is reported that there are typical chlamydia inclusions in two autopsy lung samples of the patients who died of pneumonia, and the chlamydia granules in the lung cytoplasm are very typical.
Material 2. (February 18) Many experts in Guangdong believe that it is too early to basically determine the pathogen as chlamydia. The reason is that there are many differences between SARS and chlamydia pneumonia. Virus inclusion bodies were found in the autopsy of the first SARS patient. Zhong Nanshan, an academician of China Academy of Engineering, a famous respiratory disease expert and a Guangdong SARS treatment expert, said, If it is chlamydia, why do we take a lot of anti-chlamydia drugs in clinic, but it has no effect?
Material 3. Canadian research institutions published the whole genome sequence of novel coronavirus for the first time on April 13, and the US Centers for Disease Control and Prevention also published their results on April 14. According to the press release issued by the US Centers for Disease Control and Prevention, the novel coronavirus gene contains 29,727 nucleotides, which is the same as the virus gene drawn by Canadian researchers, with a difference of only 15 nucleotides.
Material 4 Xinhuanet Geneva, April 16-David Hyman, Executive Director of the Infectious Diseases Department of the World Health Organization, announced here on April 16 that through the joint efforts of researchers from all over the world, a variant of coronavirus has finally been officially confirmed as the pathogen of atypical pneumonia.
Please combine your knowledge to analyze and answer the following questions:
1, Chlamydia belongs to biology, it has no typical nucleus, only one nuclear region, but it does not surround this region, and this region is where the genetic material lies.
2, virus and chlamydia have substance or structure is ()
A. Ribosome B. Cell membrane C. Nucleic acid D. Mitochondria
3. Genes are DNA fragments, and gene sequencing needs to analyze the sequence of DNA.
4. From the transmission route, SARS is an infectious disease. Because the pathogens of such diseases spread in the air through droplets, they often occur in seasons. In the prevention of atypical pneumonia, frequent hand washing is a measure to prevent infectious diseases.
5. From the materialistic point of view, what does it mean that people failed to make a correct understanding of pathogens in the early stage of SARS?
6. From the epistemological point of view, the pathogen of atypical pneumonia can basically be identified as chlamydia by China Center for Disease Control and Prevention. Through the joint efforts of researchers all over the world, it was finally confirmed that a variant of coronavirus was the pathogen that caused atypical pneumonia. What does it say?
7. From the perspective of political common sense, what does it mean for China state organs to stick to the truth, correct mistakes and strengthen prevention and control on the SARS issue?
Answer to question 6: 1, prokaryote, storage replication 2, C 3, base (nucleotide) 4 with genetic effect, respiratory tract, winter and spring, cutting off transmission route 5, indicating that there are no unknowns in the world, only things that have not yet been recognized. 6. Explain that practice is the source of cognition, and practice is the only criterion to test whether cognition is correct or not. Explain that state organs adhere to the principle of being responsible to the people.
Swine flu, bird flu or SARS, which is more serious and more difficult to treat ~ Infectious: SARS A, bird flu, bird flu does not spread from person to person.
Mortality and severity: avian influenza and SARS.
Influenza A is mainly transmitted through respiratory tract. Generally speaking, talking can spread viruses, and there are no completely effective measures. Suggestion: 1. If you have cold symptoms, see a doctor promptly, wear a mask and isolate yourself from the surrounding people for 3 days. 2. Strengthen physical exercise.
Which is worse, bird flu or swine flu ... your idea is the most ridiculous. These two are more difficult than winning the lottery.
Which is more serious, dog flu, swine flu and bird flu? The landlord's question is unanswerable. But I can probably understand what the landlord means.
This should be said separately,
In terms of virulence, H5N 1 highly pathogenic avian influenza is more severe;
It is contagious. Influenza a N 1N 1 is more serious.
Swine flu or bird flu, which is more terrible? Is there any medication? They are all orthomyxoviridae, multi-segment single-stranded negative-stranded RNA.
Swine flu and bird flu are both human and animal diseases.
As long as viral infection is incurable or unlikely, we only have vaccines to prevent viruses, but few drugs can treat viral diseases.
But you can take antiviral drugs, and immune-enhancing drugs may make the body resist the past.
Pork can be eaten as long as it is cooked.
The influenza virus can be inactivated at 56 degrees 30 minutes or 60 degrees 20 minutes, which means death. Try not to touch raw pork or chicken with wounds.
I also tell you that you are not in this line of work and don't understand the market. The meat we eat is basically sick. You should know that some of them are not contagious to humans.
Bird flu and cold have gone, so just tell the doctor about your current situation.
Bird flu and eating eggs will not, eggs are sterile.
At present, the problems of swine flu and bird flu are only speculations by medical authorities. Therefore, it is possible to exchange them. In this way, the treatment is more difficult and the transmission speed is faster (taking people as the host). Some medical institutions are studying this kind of topic (I'm afraid it's a treatment). Only those who have recovered from illness have antibodies, and the elderly have low immunity, and their autoimmune reaction will not be too strong, so they will not die easily.
Answer them all!
At present, which is more terrible, bird flu or SARS? Some bird flu has a higher mortality rate, while SARS is more harmful. Both are infectious diseases that threaten human beings.
What's the difference between bird flu and a cold? Avian influenza, popularly known as viral influenza of birds, is an infectious disease caused by influenza A virus. From respiratory system to severe systemic septicemia, the mortality rate of birds after infection is very high. The main source of infection is chickens and ducks, and people will be infected by direct contact with birds infected with H5N 1 virus and their droppings or by direct contact with H5N 1 virus. In addition, droplets and contact with respiratory secretions are also routes of transmission.
After people suffer from avian influenza, the incubation period generally does not exceed 7 days, and the early symptoms are very similar to other influenza, which are mainly shown in the following table.
Symptoms are fever, runny nose, stuffy nose, cough, sore throat, headache and general malaise. Most patients are cured well, with short course of disease, quick recovery and no sequelae. However, a few patients, especially those who are older and treated too late, will quickly develop into various complications such as progressive pneumonia, acute respiratory distress syndrome, pulmonary hemorrhage and pleural effusion and die.
Influenza is generally divided into three types, namely, type A, type B and type C. Type B and type C influenza generally only spread among people and rarely spread to other animals. Influenza A is mostly avian influenza, and avian influenza virus rarely causes people to get sick.
Avian influenza mainly spreads among birds and occasionally infects people. Its clinical manifestations are similar to human influenza, but human avian influenza has severe symptoms, many complications, high mortality and ineffective vaccination, which is different from ordinary influenza.
What is the relationship between avian influenza and other influenza?
In addition to avian influenza, the common influenza is human influenza, equine influenza and swine flu. Avian influenza is closely related to human influenza and human health. Because of the small interspecific difference between pigs and humans, avian influenza virus can cross with human influenza virus in the intermediate host (pig) to produce a new type of influenza virus that can infect humans.