December 1, 2023.
It is the 36th World AIDS Day
The theme of this year's propaganda in our country is:
"Unite social forces to fight AIDS".
AIDS not only endangers the health and safety of individuals and affects the happiness of families, but also seriously threatens economic development and social harmony and stability.
The factors involved in the spread of HIV/AIDS are complex and widespread, and the prevention and treatment of HIV/AIDS involves all aspects of society, requiring the active participation of the whole society, and more importantly, everyone taking responsibility for their own health.
There are many measures to prevent HIV infection, such as cutting back on sexual partners, using condoms properly, staying away from drugs, and screening for HIV before and during pregnancy. In addition, drug prophylaxis is also very effective. There are two types of pharmacological prophylaxis: pre-exposure prophylaxis and post-exposure prophylaxis.
Pre-exposure prophylaxis
Pre-exposure prophylaxis, or Prep, is a way to prevent HIV infection by taking antiviral drugs in advance. There are 3 ways to prevent exposure:
One of the most commonly used is to take one tablet of emtricitabine tenofovir every dayStart taking the drug a week in advance, and after taking the drug for a week, the body will reach a sufficient concentration of the drug. After the occurrence of high-risk behaviors, take it for another week, and if you are not prepared to have high-risk behaviors in the near future, you can stop taking the drug. Emtricitabine tenofovir alafenol tablets can also be used as a once-daily dose, but it should only be used in men and transgender women.
The second approach to pre-exposure prophylaxis is "medication on demand" (211 dosing method) for people who have sex with men。This method requires taking 1 amptricitabine tenofovir tablet 2 to 24 hours before the onset of high-risk sexual activity, and 1 tablet of emtricitabine tenofovir 24 hours and 48 hours after the first dose of the drug after the onset of high-risk sexual activity. Men who have infrequent high-risk sexual behavior and are prepared in advance can use the 211 method for pre-exposure prophylaxis.
The third method of pre-exposure prophylaxis is captegravir intramuscularly every 2 months without oral medication. At present, there is no drug for captegravir in China.
It is important to note that people who are not infected with HIV can take PrEP.
Post-exposure prophylaxis
Post-exposure prophylaxis (PEP) is commonly known as "AIDS regret medicine". It can effectively reduce the transmission of HIV after exposure and has been widely used in clinical practice. It is recommended that all people who have had a history with an exposed source of behavior that could lead to HIV infection should use PEP as soon as possible.
There is a 72-hour requirement in PEPThat is, it is required to take the drug within 72 hours (the sooner the better) of the high-risk behaviorIf the time is more than 72 hours, there is no preventive effect, and it is not recommended to take the drug.
Why is the first time to block HIV infection 72 hours?HIV mainly enters the human body through broken ** or mucous membranes, and after entering, HIV first attacks immune cells at the site of invasion and local replication occurs. Subsequently, HIV enters the local lymph nodes, replicates in the lymph nodes, and travels throughout the body through the bloodstream, a process that takes 48-72 hours. Post-exposure prophylaxis is given for 4 weeks.
Tips
Whether it is pre-exposure or post-exposure prophylaxis, it is not possible to use drugs without authorization, and it is necessary to visit a hospital, be evaluated by a doctor, conduct relevant laboratory tests, determine the medication plan, and regularly follow up with the doctor's requirements for laboratory tests. Neither pre-exposure prophylaxis nor post-exposure prophylaxis is 100% successful, and avoiding high-risk behaviors is the most critical.
*: Healthy Beijing.
Editor in charge: Qing Yu.
Capital Cyber Police.