首页
登录
职称英语
HIV and Its Transmission Research has revealed a g
HIV and Its Transmission Research has revealed a g
游客
2023-07-28
17
管理
问题
HIV and Its Transmission
Research has revealed a great deal of valuable medical, scientific, and public health information about the human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). The ways in which HIV can be transmitted have been clearly identified. Unfortunately, false information or statements that are not supported by scientific findings continue to be shared widely through the Internet or popular press. Therefore, the Centers for Disease Control and Prevention (CDC) has prepared this fact sheet to correct a few misperceptions about HIV.
How HIV Is Transmitted
HIV is spread by sexual contact with an infected person, by sharing needles (primarily for drug injection) with someone who is infected, or, less commonly, through transfusions of infected blood or blood clotting factors (凝血因子). Babies born to HIV-infected women may become infected before or during birth or through breast-feeding after birth.
Some people fear that HIV might be transmitted in other ways; however, no scientific evidence supporting any of these fears has been found. If HIV were being transmitted through other routes (such as through air, water, or insects), the pattern of reported AIDS cases would be much different from what has been observed. For example, if mosquitoes could transmit HIV infection, many more young children and preadolescents would have been diagnosed with AIDS.
All reported cases suggesting new or potentially unknown routes of transmission are thoroughly investigated by state and local health departments with the assistance, guidance, and laboratory support from CDC. No additional routes of transmission have been recorded, despite a national sentinel (监测) system designed to detect just such an occurrence.
The following paragraphs specifically address some of the common misperceptions about HIV transmission.
HIV in the Environment
Scientists and medical authorities agree that HIV does not survive well in the environment, making the possibility of environmental transmission remote. HIV is found in varying concentrations or amounts in blood, semen (精液), vaginal (阴道的) fluid, breast milk, saliva (唾液), and tears. To obtain data on the survival of HIV, laboratory studies have required the use of artificially high concentrations of laboratory-grown virus. Since the HIV concentrations used in laboratory studies are much higher than those actually found in blood or other specimens, drying of HIV-infected human blood or other body fluids reduces the theoretical risk of environmental transmission to that which has been observed—essentially zero. Incorrect interpretation of conclusions drawn from laboratory studies has unnecessarily alarmed some people.
Results from laboratory studies should not be used to assess specific personal risk of infection because: (1) The amount of virus studied is not found in human specimens or elsewhere in nature, and (2) no one has been identified as infected with HIV due to contact with an environmental surface. Additionally, HIV is unable to reproduce outside its living host except under laboratory conditions. Therefore, it does not spread or maintain infectiousness outside its host.
Households
Although HIV has been transmitted between family members in a household setting, this type of transmission is very rare. These transmissions are believed to have resulted from contact between skin or mucous membranes (黏膜) and infected blood. To prevent even such rare occurrences, precautions should be taken in all settings "including the home" to prevent exposure to the blood of persons who are HIV infected, at risk for HIV infection, or whose infection and risk status are unknown, For example.
Gloves should be worn during contact with blood or other body fluids that could possibly contain visible blood, such as urine, feces (粪便), or vomit.
Cuts, sores, or breaks on both the caregiver’s and patient’s exposed skin should be covered with bandages.
Hands and other parts of the body should be washed immediately after contact with blood or other body fluids, and surfaces soiled with blood should be disinfected appropriately.
Practices that increase the likelihood of blood contact, such as sharing of razors and toothbrushes, should be avoided.
Businesses and Other Settings
There is no known risk of HIV transmission to co-workers, clients, or consumers from contact in settings such as food-service establishments (see information on survival of HIV in the environment). Food-service workers known to be infected with HIV need not be restricted from work unless they have other infections or illnesses for which any food-service worker, regardless of HIV infection status, should be restricted. CDC recommends that all food-service workers follow recommended standards and practices of good personal hygiene and food sanitation.
Kissing
Casual contact through closed-mouth or "social" kissing is not a risk for transmission of HIV. Because of the potential for contact with blood during "French" or open-mouth kissing, CDC recommends against engaging in this activity with a person known to be infected. However, the risk of acquiring HIV during open-mouth kissing is believed to be very low. CDC has investigated only one case of HIV infection that may be attributed to contact with blood during open-mouth kissing.
Saliva, Tears, and Sweat
HIV has been found in saliva and tears in very low quantities from some AIDS patients. It is important to understand that finding a small amount of HIV in a body fluid does not necessarily mean that HIV can be transmitted by that body fluid. HIV has not been discovered from the sweat of HIV-infected persons. Contact with saliva, tears, or sweat has never been shown to result in transmission of HIV.
Insects
From the onset of the HIV epidemic, there has been concern about transmission of the virus by biting and bloodsucking insects. However, studies conducted by researchers at CDC and elsewhere have shown no evidence of HIV transmission through insects—even in areas where there are many cases of AIDS and large populations of insects such as mosquitoes. Lack of such outbreaks, despite intense efforts to detect them, supports the conclusion that HIV is not transmitted by insects.
The results of experiments and observations of insect biting behaviour indicate that when an insect bites a person, it does not inject the blood of its own or a previously bitten person or animal into the next person bitten. Such diseases as yellow fever and malaria (疟疾) are transmitted through the saliva of specific species of mosquitoes. However, H1V lives for only a short time inside an insect and, unlike organisms that are transmitted via insect bites, HIV does not reproduce (and does not survive) in insects. Thus, even if the virus enters a mosquito or other sucking or biting insect, the insect does not become infected and cannot transmit HIV to the next human it feeds on or bites. [br] Incorrect interpretation of lab conclusions leads some people to believe that HIV can be transmitted in the environment.
选项
A、Y
B、N
C、NG
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/2875388.html
相关试题推荐
Asresearcherslearnmoreabouthowchildren’sintelligencedevelops,theyar
Asresearcherslearnmoreabouthowchildren’sintelligencedevelops,theyar
ResearchersinJapanhavediscoveredsomeeye-openingnewsaboutcoffee:It
ResearchersinJapanhavediscoveredsomeeye-openingnewsaboutcoffee:It
ResearchersinJapanhavediscoveredsomeeye-openingnewsaboutcoffee:It
ResearchersinJapanhavediscoveredsomeeye-openingnewsaboutcoffee:It
Americansbelievesomuchinmovingaheadthattheyare【C1】______researchi
Americansbelievesomuchinmovingaheadthattheyare【C1】______researchi
Americansbelievesomuchinmovingaheadthattheyare【C1】______researchi
Americansbelievesomuchinmovingaheadthattheyare【C1】______researchi
随机试题
Willyoupleaselendmethenovelwhenyou______?A、willfinishB、finishC、fini
光合作用中淀粉形成的部位()A.叶绿体中的间质 B.叶绿体中的基粒片层 C
根据FIDIC《土木工程施工合同条件》,下列关于履约担保的说法中,错误的是()
下列方法与检查细菌动力无关的是A.压滴法B.半固体穿刺C.革兰染色D.悬滴标本镜
Thechangeinthatvillagewasmiraculou
以下应符合溶化性要求的是A.混悬性颗粒剂 B.肠溶颗粒剂 C.控释颗粒剂
下边四个图形中,只有一个是由上边的四个图形拼合(只能通过上、下、左、右平移)而成
如图,面积为144的四边形ABCD中,对角线AC与BD相交于点E,已知BD=24
(2017年真题)对某一类高层宾馆进行防火检查,查阅资料得知,该宾馆每层划分为2
胆囊结石临床表现各异,主要取决于A.结石的大小、部位、是否梗阻、有无感染 B.
最新回复
(
0
)