一般信息
什么是乙型肝炎?
乙型肝炎是世界上最常见的肝脏感染。它是由乙型肝炎病毒 (HBV) 引起的,该病毒会攻击和伤害肝脏。它通过血液、无保护性行为、共用或重复使用的针头传播,在怀孕或分娩期间由受感染的母亲传染给新生婴儿。大多数感染的成年人能够毫无问题地消除乙型肝炎病毒。然而,一些成年人和大多数受感染的婴儿和儿童无法消除这种病毒,并将发展为慢性(终生)感染。
好消息是已有安全的疫苗可以预防乙型肝炎感染,和针对已感染人士的新治疗方法。
有多少人受乙型肝炎影响?
全世界 20 亿人(3 人中就有 1 人)已感染乙型肝炎;2.57 亿人为慢性感染(这意味着他们无法消除这种病毒)。据估计,每年有 70 万人死于乙型肝炎及其并发症。
为什么乙型肝炎在世界某些地区更常见?
乙型肝炎可以感染任何年龄或种族的任何人,但是来自世界上乙型肝炎较为常见的部分地区(如亚洲、非洲和南美洲部分地区、东欧以及中东)的人,受感染的风险要高得多。出生(或其父母出生)在这些地区的美国人中,乙型肝炎也较为常见。
乙型肝炎在世界上某些地区更为常见,因为在这些地区有更多的人已经感染乙型肝炎。虽然乙型肝炎并非“亚洲疾病”或者“非洲疾病”,但它影响着来自这些地区的数亿人——因此,这里有更多的人会将乙型肝炎病毒传给他人。这增加了您受感染的风险。因为有较小一部分的受感染者为西方人,这一群体的感染风险较低。
在乙型肝炎较为常见的地区,人们通常在新生儿时期就受到感染——在分娩过程中由母亲不知不觉地将病毒传给婴儿。如果幼儿与受感染的家庭成员在日常生活中接触密切,他们也面临风险。婴儿和儿童更容易发展为慢性乙型肝炎感染,因为他们未成熟的免疫系统难以消除这种病毒。
如果您,或者您的家人,来自地图上的深蓝色区域,您可能会面临更大的乙型肝炎感染风险,并且应该和医生谈谈关于接受测试的事宜。
为什么我应该关心乙型肝炎?
慢性乙型肝炎可以导致严重的肝脏疾病,如肝硬化或肝癌。接受测试十分重要,因为早期的诊断可以使您尽早治疗,从而可以挽救您的生命。另外,感染者可以将病毒传播给其他人。因为大多数人不知道自己受感染,所以他们会不知不觉地将之传播给其他许多人。如果人们不接受测试,乙型肝炎病毒可以在一个家庭的几代人和整个社区中传播下去。
一个常见误区是,乙肝可以“遗传”,因为一个家族中几代人可能都受感染。但乙型肝炎不是遗传性疾病——乙型肝炎是由病毒引起的,通常因母婴传播或者意外的居家血液接触而在家庭成员之间传播。通过接受测试、接种疫苗和治疗,家庭可以打破乙型肝炎感染的循环。
为什么乙型肝炎如此危险?
乙型肝炎有危险,因为它是一种“无声的感染”,可以使人不知不觉地受到感染。大多数乙型肝炎感染者未觉察自己感染,会不知不觉地通过自己的血液和已感染的体液将病毒传给他人。对于那些慢性感染者,在以后的生活中,发展为肝功能衰竭、肝硬化和/或肝癌的风险会增加。该病毒可以悄无声息、持续不断地长年攻击肝脏而不被发觉。
什么是急性乙型肝炎?
急性乙型肝炎感染可持续多达六个月(有症状或无症状),感染者可在此期间将病毒传给他人。
急性感染的症状可能包括食欲减退、关节和肌肉疼痛、低烧和可能胃痛。虽然大多数人不会体验到症状,但症状会在感染后的 60-150 天出现,平均为 3 个月。有些人可能出现更严重的症状,如恶心、呕吐、黄疸(眼睛和皮肤发黄),或者胃胀,这些可能导致他们去看卫生保健提供者。
仅需简单的验血即可辨别一个人的血液中是否存在乙型肝炎病毒。如果您已被诊断为急性乙型肝炎,医生需要在 6 个月后再次测试您的血液,以确定您是已康复,还是发展为慢性乙型肝炎感染。在您的卫生保健提供者确认您的验血表明您的血液中不再存有乙型肝炎病毒之前,保护其他人避免感染可能性是十分重要的。让您的性伴侣和家庭成员(或与您密切接触的家属)接受乙型肝炎测试也是十分重要的。如果他们尚未受感染,而且尚未接受乙型肝炎疫苗接种,那么他们就应该开始注射乙型肝炎疫苗系列。
急性乙型肝炎患者不会被建议采用特定的乙型肝炎治疗方法——没有可以消除急性乙型肝炎感染的治疗方法,而且大多数人在成年时期受到感染,可自行痊愈。有时,症状严重者可能会住院接受一般支持。休息和控制症状是这一医疗保健的主要目标。一种名为“暴发型肝炎”的罕见、危及生命的病症,会伴随新的急性感染出现,并且需要立即、紧急的医疗护理,因为患者可能会突然出现肝衰竭。
急性乙型肝炎感染期间照顾您的肝脏的简单技巧就是要避免酒精,停止或限制吸烟,食用健康食物,避免油腻或高脂肪的食物,以及与您的卫生保健提供者谈论您正在服用的任何药物(处方药、非处方药物、维生素或草药补充剂),以确保它们对您的肝脏是安全的。您如有任何其他疑问,这是提问的好时机。使用维生素和肝脏健康补充剂可能不会帮助您恢复健康,实际上对肝脏的影响可能弊大于利。
务必去您的卫生保健提供者处复诊,以接受确认您是否从急性感染中恢复所需的任何其他验血。
什么是慢性乙型肝炎?
乙型肝炎病毒测试呈阳性超过六个月者(在其首次验血结果之后)被诊断为患慢性感染。这意味着他们的免疫系统无法消除乙型肝炎病毒,而且该病毒仍然存在于他们的血液和肝脏中。已有治疗和控制慢性感染的有效方法,但是没有治愈方法。如果您是慢性感染者,很可能在您的余生中病毒都会留在您的血液里。
慢性乙型肝炎患者会不知不觉地将病毒传给他人。慢性乙型肝炎也可以导致严重的肝脏疾病,如肝硬化或肝癌。并非每位慢性感染者都会发展为严重的肝脏疾病。然而,他们的可能性比未感染者更大。
发展为慢性乙型肝炎感染的风险与首次感染乙型肝炎病毒的年龄有关:
- 90% 受感染的新生儿和婴儿会发展为慢性乙型肝炎感染
- 高达 50% 受感染的儿童(1-5 岁)会发展为慢性乙型肝炎感染
- 5%-10% 受感染的成年人会发展为慢性乙型肝炎感染(即,90% 会恢复)
获悉自己患有慢性乙型肝炎感染会非常令人沮丧。因为大多数人没有症状,并在他们最初接触乙型肝炎病毒后数十年被诊断出来,所以被诊断为患有慢性乙型肝炎感染会令人感到震惊和意外。好消息是,大多数慢性乙型肝炎患者预计会活得健康长寿。
受感染的孕妇可以在分娩期间将病毒传给新生儿。因此,由于新生儿在出生时患慢性感染的风险很高,世界卫生组织 (WHO) 和美国疾病控制和预防中心 (CDC) 建议,所有婴儿在出生后 12-24 小时内接受首剂乙型肝炎疫苗接种。如果您已怀孕并且您知道自己受感染,则您可以确保您的宝宝在分娩后的 12-24 小时内接受首剂乙型肝炎疫苗接种!
尽管慢性乙型肝炎感染没有治愈方法,但已有有效的药物疗法可以控制乙型肝炎病毒并阻止它损害肝脏。还有处于研究阶段的有前景新药,可以在不久的将来提供治愈方法。尽管慢性乙型肝炎患者发展为严重肝病或肝癌的风险高于未感染者,但仍有许多简单的事情可以帮助降低他们的风险。
- 每六个月(或至少每年)安排一次与乙型肝炎知识渊博的肝脏专家或卫生保健提供者的定期就诊,以便他们可以监测您的肝脏健康。
- 与您的卫生保健提供者讨论您的慢性乙型肝炎感染治疗是否有助于预防严重的肝脏疾病或肝癌。
- 确保您的卫生保健提供者在您的定期就诊期间对您进行肝癌筛查,因为早发现等同于治疗选择更多和生命更长久。
- 避免或限制酒精和吸烟,因为二者都会对您的肝脏造成巨大压力。
- 合理健康饮食,吃大量蔬菜,因为油炸、油腻的食物会苛待您的肝脏。
成为“慢性携带者”意味着什么?
当某人患有慢性乙型肝炎感染时,他们的医生可能会称其为“慢性携带者”。作为“慢性携带者”意味着您患有慢性乙型肝炎感染,可以将病毒传给他人,并且您应该由医生来控制您的感染。
乙型肝炎有治愈方法吗?
大多数成年人无需药物治疗,急性感染即可自行痊愈。对于发展为慢性乙型肝炎感染的成年人、儿童和婴儿,目前没有治愈方法。但好消息是,有一些治疗方法可以通过使病毒减速来帮助减缓慢性感染者的肝病进展。如果产生的乙型肝炎病毒较少,那么对肝脏的损伤就会较少。
凭着所有令人振奋的新研究,有很大希望在不久的将来找到慢性乙型肝炎的治愈方法。访问我们的 Drug Watch(药品观察 获取研发中的其他有前景药物的清单。
治疗我的乙型肝炎有哪些选择?
对于急性感染,除了休息和支持性措施来控制任何症状外,一般没有其他治疗方法。
对于慢性乙型肝炎,有几种可用的治疗方法。重要的是要了解并非每位慢性乙型肝炎患者都需要治疗。您的医生会帮助您决定您是需要药物治疗,还是可以等待并监控您的病情。
有几种抗病毒药物可以减缓或阻止乙型肝炎病毒的复制,从而减少肝脏炎症和损伤。这些抗病毒药物为丸剂,每天服用一次,疗程至少 1 年,通常更久。目前有 6 种经美国 FDA 批准的抗病毒药物,但是只有 3 种“一线”抗病毒药物获得推荐:替诺福韦酯(Viread/TDF)、替诺福韦艾拉酚胺(Vemlidy/TAF)和恩替卡韦(Baraclude)。推荐使用一线抗病毒药物,因为它们更安全、最有效。对一线抗病毒治疗无应答或无法获取一线抗病毒治疗的患者可使用其他选择:替比夫定(Tyzeka,Sebivo)、阿德福韦酯(Hepsera)和拉米夫定(Epivir-HBV,Zeffix,Heptodin)。
尽管 FDA 已经批准这些用于慢性乙型肝炎的抗病毒药物,但它们不能提供彻底治愈。然而,它们可以大大减少发展肝损伤和肝癌的风险。抗病毒药物不能随意停止和开始,这就是在开始治疗慢性乙型肝炎之前需要由知识渊博的医生进行彻底评估是如此重要的缘由。
还有免疫调节药可以增强免疫系统,以帮助控制乙型肝炎病毒。它们在 6 个月至 1 年的时间里以注射方式给药。最常见的处方药物包括干扰素 alfa-2b (Intron A) 和聚乙二醇干扰素 (Pegasys)。
您和您的医生在决定哪种治疗选择(若有的话)最适合您之前需要讨论各种治疗选择。对许多人来说,这些药物会减少或阻止乙型肝炎病毒。这导致病人在数月内感觉良好,这是因为病毒对肝脏的损伤有所减缓,或者经长期服用后甚至在某些情况下出现逆转。
如需获取经 FDA 批准的药物和其他处于研发中的有前景药物的完整清单,请访问我们的 Drug Watch(药品观察。
General Information
What is hepatitis B?
Hepatitis B is the world's most common liver infection. It is caused by the hepatitis B virus (HBV), which attacks and injures the liver. It is transmitted through blood, unprotected sex, shared or re-used needles, and from an infected mother to her newborn baby during pregnancy or delivery. Most infected adults are able to get rid of the hepatitis B virus without any problems. However, some adults and most infected babies and children are unable to get rid of the virus and will develop chronic (life-long) infection.
The good news is that there is a safe vaccine to prevent a hepatitis B infection and new treatments for those already infected with hepatitis B.
How many people are affected by hepatitis B?
Worldwide, 2 billion people (1 out of 3 people) have been infected with hepatitis B; and 257 million people are chronically infected (which means they are unable to get rid of the virus). An estimated 700,000 people die each year from hepatitis B and its complications.
Why is hepatitis B more common in some parts of the world?
Hepatitis B can infect any person of any age or ethnicity, but people from parts of the world where hepatitis B is common, such as Asia, parts of Africa and South America, Eastern Europe, and the Middle East, are at much higher risk for getting infected. Hepatitis B is also common among Americans who were born (or whose parents were born) in these regions.
Hepatitis B is more common in certain regions of the world because there are so many more people already infected with hepatitis B in these regions. Although hepatitis B is not an "Asian disease" or an “African disease,” it affects hundreds of millions of people from these regions – so there are more people who can pass the hepatitis B virus on to others. This increases the risk that you could get infected. Since there is a smaller number of Westerners who are infected, this group has a lower risk of infection.
In regions where hepatitis B is common, people are usually infected as newborns - from a mother who unknowingly passes the virus to her baby during delivery. Young children are also at risk if they live in close daily contact with an infected family member. Babies and children are more likely to develop a chronic hepatitis B infection because their young immune systems have trouble getting rid of the virus.
If you, or your family, is from an area of the map that is darker blue, you might be at greater risk for hepatitis B infection and should talk to a doctor about getting tested.
Why should I be concerned about hepatitis B?
Chronic hepatitis B can lead to serious liver disease such as cirrhosis or liver cancer. It's important to get tested because early diagnosis can lead to early treatment which can save your life. Also, people who are infected can spread the virus to others. Since most people don't know they are infected, they are unknowingly spreading it to many other people. If people are not tested, hepatitis B can pass through several generations in one family and throughout the community.
One common myth is that hepatitis B can be "inherited" since several generations in one family may be infected. But hepatitis B is NOT a genetic disease -- hepatitis B is caused by a virus, which is often transmitted among family members due to mother-to-child transmission or accidental household exposure to blood. Families can break the cycle of hepatitis B infection by getting tested, vaccinated and treated.
Why is hepatitis B so dangerous?
Hepatitis B is dangerous because it is a “silent infection” that can infect people without them knowing it. Most people who are infected with hepatitis B are unaware of their infection and can unknowingly pass the virus to others through their blood and infected bodily fluids. For those who become chronically infected, there is an increased risk of developing liver failure, cirrhosis and/or liver cancer later in life. The virus can quietly and continuously attack the liver over many years without being detected.
What is acute hepatitis B?
An acute hepatitis B infection may last up to six months (with or without symptoms) and infected persons are able to pass the virus to others during this time.
Symptoms of an acute infection may include loss of appetite, joint and muscle pain, low-grade fever, and possible stomach pain. Although most people do not experience symptoms, they can appear 60-150 days after infection, with the average being 3 months. Some people may experience more severe symptoms such as nausea, vomiting, jaundice (yellowing of the eyes and skin), or a bloated stomach that may cause them to see a health care provider.
A simple blood test can tell a person if the hepatitis B virus is in their blood. If you have been diagnosed with acute hepatitis B, the doctor will need to test your blood again in 6 months to figure out if you have recovered, or if you have developed a chronic hepatitis B infection. Until your health care provider confirms that your blood test shows that there is no more hepatitis B virus in your blood, it is important to protect others from a possible infection. It is also important to have your sexual partner(s) and family members (or those you live in close household contact with) tested for hepatitis B. If they have not been infected – and have not received the hepatitis B vaccine – then they should start the hepatitis B vaccine series.
People who have acute hepatitis B are not prescribed specific hepatitis B treatment – there is no treatment that will get rid of an acute hepatitis B infection, and most people infected as adults recover on their own. Sometimes, a person with severe symptoms may be hospitalized for general support. Rest and managing symptoms are the primary goals of this medical care. A rare, life-threatening condition called “fulminant hepatitis” can occur with a new acute infection and requires immediate, urgent medical attention since a person can go into sudden liver failure.
Simple tips for taking care of your liver during an acute hepatitis B infection are to avoid alcohol, stop or limit smoking, eat healthy foods, avoid greasy or fatty foods, and talk to your health care provider about any medications you are taking (prescriptions, over-the-counter medications, vitamins or herbal supplements) to make sure they are safe for your liver. This is a good time to ask any other questions you may have. The use of vitamins and liver health supplements will likely not assist your recovery and may actually cause more harm than good to the liver.
Be sure to follow-up with your health care provider for any additional blood tests that are needed to confirm your recovery from an acute infection.
What is chronic hepatitis B?
People who test positive for the hepatitis B virus for more than six months (after their first blood test result) are diagnosed as having a chronic infection. This means their immune system was not able to get rid of the hepatitis B virus and it still remains in their blood and liver. There are effective ways to treat and manage a chronic infection, but there is no cure. If you are chronically infected, the virus will likely remain in your blood for the rest of your life.
People who have chronic hepatitis B can unknowingly pass the virus on to others. Chronic hepatitis B can also lead to serious liver diseases, such as cirrhosis or liver cancer. Not every person who is chronically infected will develop serious liver disease. However, they have a greater chance than someone who is not infected.
The risk of developing a chronic hepatitis B infection is related to the age at which one first becomes infected with the hepatitis B virus:
- 90% of infected newborns and babies will develop a chronic hepatitis B infection
- Up to 50% of infected children (1-5 years) will develop a chronic hepatitis B infection
- 5-10% of infected adults will develop a chronic hepatitis B infection (that is, 90% will recover)
Learning that you have a chronic hepatitis B infection can be very upsetting. Because most people do not have symptoms and can be diagnosed decades after their initial exposure to the hepatitis B virus, it can be a shock and a surprise to be diagnosed with a chronic hepatitis B infection. The good news is that most people with chronic hepatitis B should expect to live a long and healthy life.
Infected pregnant women can pass the virus to their newborns during childbirth. Therefore, since the risk of newborns becoming chronically infected at birth is high, both the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) recommend that all infants receive the first dose of the hepatitis B vaccine within 12-24 hours after birth. If you are pregnant and you know that you are infected, you can make sure that your baby gets the first dose of the hepatitis B vaccine within 12-24 hours after delivery!
While there is no cure for chronic hepatitis B infection, there are effective drug therapies that can control the hepatitis B virus and stop it from damaging the liver. There are also promising new drugs in the research phase that could provide a cure in the very near future. Although the risk of developing a serious liver disease or liver cancer is higher for those living with chronic hepatitis B than those who are not infected, there are still many simple things a person can do to help reduce their risk.
- Schedule regular visits every six months (or at least every year) with a liver specialist or a health care provider who is knowledgeable about hepatitis B so they can monitor the health of your liver.
- Talk to your health care provider about whether treatment for your chronic hepatitis B infection would be helpful in preventing serious liver disease or liver cancer.
- Make sure that your health care provider screens you for liver cancer during your regular visits since early detection equals more treatment options and a longer life.
- Avoid or limit alcohol and smoking since both cause a lot of stress to your liver.
- Eat a healthy diet with lots of vegetables since fried, greasy foods are hard on your liver.
What does it mean to be a “chronic carrier”?
When someone has a chronic hepatitis B infection, their doctor may refer to them as being a “chronic carrier.” Being a “chronic carrier” means that you have a chronic hepatitis B infection, can pass the virus on to others, and you should be managed by a doctor for your infection.
Is there a cure for hepatitis B?
Most adults will recover from an acute infection on their own without the need for medication. For adults, children and infants who develop a chronic hepatitis B infection, there is currently no cure. But the good news is there are treatments that can help slow the progression of liver disease in chronically infected persons by slowing down the virus. If there is less hepatitis B virus being produced, then there is less damage being done to the liver.
With all of the new exciting research, there is great hope that a cure will be found for chronic hepatitis B in the near future. Visit our Drug Watch for a list of other promising drugs in development.
What options are there to treat my hepatitis B?
For an acute infection, there is generally no treatment other than rest and supportive measures to manage any symptoms.
For chronic hepatitis B, there are several treatments available. It is important to understand that not everyone with chronic hepatitis B needs treatment. Your doctor will help you decide if you need medication or if you can wait and monitor your condition.
There are several antiviral medications that slow down or stop the hepatitis B virus from replicating, which reduces the inflammation and damage to the liver. These antivirals are taken as a pill once a day for at least 1 year, usually longer. There are 6 U.S. FDA approved antivirals, but only three “first-line” antivirals are recommended: tenofovir disoproxil (Viread/TDF), tenofovir alafenamide (Vemlidy/TAF) and entecavir (Baraclude). First-line antivirals are recommended because they are safer and most effective. For people who do not respond to, or have access to, the first-line antiviral treatments, other options are available: telbivudine (Tyzeka, Sebivo), adefovir dipivoxil (Hepsera), and lamivudine (Epivir-HBV, Zeffix, Heptodin).
Although the FDA has approved these antivirals for chronic hepatitis B, they do not provide a complete cure. They can, however, greatly decrease the risk of developing liver damage and liver cancer. Antivirals are not meant to be stopped and started, which is why a thorough evaluation by a knowledgeable doctor is so important before beginning treatment for chronic hepatitis B.
There are also immunomodulator drugs that boost the immune system to help control the hepatitis B virus. They are given as injections over 6 months to 1 year. The most commonly prescribed include interferon alfa-2b (Intron A) and pegylated interferon (Pegasys).
You and your doctor will need to discuss the treatment options before deciding which one, if any, is best for you. For many people, these medications will decrease or stop the hepatitis B virus. This results in patients feeling better within a few months because liver damage from the virus is slowed down, or even reversed in some cases, when taken long-term.
For a complete list of FDA approved drugs and other promising drugs in development for hepatitis B, visit our Drug Watch.