herpes viruses are a type of enveloped double-stranded DNA virus. Among the more than 100 herpes viruses that have been discovered, only 8 can infect humans and are called human herpes viruses (HHV). . In addition to varicella-zoster virus (VZV), the other seven are herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), Epstein-Barr virus (EBV), human cytomegalovirus ( CMV), human herpesvirus type 6 (HHV-6), human herpesvirus type 7 (HHV-7), and human herpesvirus type 8 (HHV-8, also known as Kaposi's sarcoma herpesvirus KSHV) that can be contracted by immunocompromised patients . The characteristic of
Herpesviridae virus is that the virus persists in a latent state in the host body, as if it is like a landmine buried inside the human body. Once certain conditions are met, it will detonate.
The most common herpes viruses-herpes simplex virus types 1 and 2 (HSV-1 and HSV-2)
HSV-1 and HSV-2 both belong to the alphaherpesviridae family and are a common and long-standing herpes virus. HSV-1 is also one of the most prevalent viruses in the world.
HSV-1 and HSV-2 herpes will appear on the lips, genitals and other parts of the body during acute attacks. After the infection recovers, the virus can lie dormant in ganglion neurons. When other diseases, fatigue, stress, etc. occur in the body, the latent virus will be activated and replicate in large quantities, causing local recurrent herpes.
There is currently no specific drug that can treat this type of herpes virus infection . Commonly used drugs such as acyclovir can only reduce clinical symptoms and shorten the course of the disease, but cannot prevent reinfection.
The most well-known herpes virus - varicella-zoster virus (VZV)
VZV also belongs to the alphaherpesviridae family. The first infection (ie, primary infection) manifests as chickenpox . After the chickenpox is cured, the virus can still lurk in In ganglion , reactivation of latent infection often results in localized skin herpes, known as herpes zoster.
At present, vaccination with chickenpox vaccine is recognized as one of the most effective and economical ways to prevent chickenpox. Starting from 2018, this city will provide free 2 doses of chickenpox vaccine to school-age children. Vaccination with 2 doses of chickenpox can more effectively reduce the occurrence of chickenpox cases. At present, the city also has the herpes zoster vaccine that can be used to prevent herpes zoster, and is available to citizens aged 50 and above on a voluntary basis and at their own expense.
The most Buddhist herpes virus - Epstein-Barr virus (EBV)
EBV belongs to the family Gammaherpesviridae. More than 90% of adults worldwide are seropositive for EBV, and most remain asymptomatically infected throughout their lives. EBV is the main pathogen of infectious mononucleosis , and can occasionally cause lymphoma and nasopharyngeal carcinoma, thymic carcinoma and other malignant tumors. According to the different nuclear antigen sequences, EBV can be divided into type 1 and type 2, and there are also mixed infections of EBV1+EBV2.
The giant among herpes viruses - human cytomegalovirus (CMV)
CMV belongs to the betaherpesviridae family. From a genome level, it is the largest human herpesvirus, about twice as large as the varicella-zoster virus. CMV virus can be transmitted through saliva, mother-to-child, organ and bone marrow transplantation, etc. The infection is very widespread among the population, and most of them are invisible infections.
However, in recent years, studies have found that some chronic diseases such as hypertension , coronary heart disease , cerebral infarction , pulmonary hypertension , type 1 and type 2 diabetes, etc. are closely related to the CMV virus, and the CMV virus can even be used as these Independent risk factors for chronic disease. In some high-risk groups, such as immunodeficient organ transplant patients, HIV-infected patients, and newborns with congenital infection, reactivation of the virus can cause diseases including CMV pneumonia, CMV colitis, and even threaten the patient's life.
There is not only love in a kiss, but also—HHV-6, HHV-7
HHV-6 and HHV-7 all belong to the betaherpesviridae family. HHV-6 and HHV-7 are mainly transmitted through saliva, so the infection is very common and is one of the common causes of infantile roseola.HHV-6 and HHV-7 infections are often self-limiting diseases. After the disease develops to a certain extent, the disease can be controlled and cured by the body's regulation. Specific treatment is not required. If it is accompanied by complications , symptomatic treatment will suffice. .
The most "unfamiliar" herpes virus - Kaposi's sarcoma herpesvirus (KSHV)
KSHV, like EBV, belongs to the family Gammaherpesviridae. In 1994, the virus was first discovered in Kaposi's sarcoma tissue of AIDS -infected patients.
KSHV is mainly transmitted through saliva, and sexual contact, blood transfusion, organ and bone marrow transplantation, and mother-to-child transmission are all considered to have important potential transmission roles. The exact infection mechanism of
KSHV is not yet clear. Usually it exists in a latent infection state in the body. When stimulated by certain factors, the virus enters a replication state and causes related diseases.
To summarize: Most human herpes viruses do not cause clinical symptoms or only mild symptoms. They are mostly self-limiting diseases. They often lurk in the human body after primary infection. As immunity weakens, they can cause secondary People with recurrent infections, immune deficiencies or serious diseases need timely medical treatment and treatment.
Pay attention to the following points to reduce the chance of infection or alleviate the symptoms of infection:
1. Good living habits, a balanced diet, and pay attention to personal hygiene.
2. Develop good fitness habits and enhance physical fitness.
3. Varicella-zoster virus infection can be prevented by vaccination.
4. If you are suspected of being infected with human herpes virus and causing physical discomfort, please go to the hospital for treatment in time.
Source: Shanghai CDC
Editor: Lu Bin
