A recent study provides more evidence that the hepatitis B virus (HBV) is linked to a variety of cancers – that’s not surprising to most of us. We also know that the HBV vaccine can prevent the infection, thereby preventing a wide range of cancers.
Despite the facts supporting the dangers of the hepatitis B virus, the anti-vaccine zealots absolutely despise the vaccine, especially since it’s usually given to newborns (with a second dose recommended at 1-2 months along with a third dose at about 12-18 months) to prevent HBV infections passed from the mother.
Let’s take a look at the hepatitis B virus and this new peer-reviewed paper that discusses the link between HBV and a number of cancers.
Hepatitis B virus illustration.
All about the hepatitis B virus
The hepatitis B virus causes hepatitis B disease. I know that is an unusual way to describe it, but one needs to contract the virus to get the disease. It’s similar to AIDS which is caused by HIV – of course, there are AIDS deniers who claim that it is not caused by the virus despite the settled science regarding the link between HIV and AIDS.
HBV is generally transmitted through blood and bodily fluids from an infected person. The signs and symptoms of an acute infection with HBV is associated with general ill-health, loss of appetite, nausea, vomiting, body aches, mild fever – it can resemble a flu infection. However, the infection then progresses to developing jaundice, The illness lasts for a few weeks (much longer than the typical course of a flu infection) – then, most individuals gradually improve. In some individuals, the infection may be asymptomatic – however, they can still pass the HBV to other people.
A few individuals may contract a more severe form of hepatitis B which causes a form of liver disease, called fulminant hepatic failure – these people may die as a result.
The most important issue is that a chronic hepatitis B virus infection, whether it is asymptomatic or not, leads to chronic inflammation of the liver. This leads to cirrhosis over a period of several years.
This type of infection increases the incidence of hepatocellular carcinoma. However, just to be absolutely clear, even in the absence of cirrhosis, the individual is still at risk from liver cancer.
Cancer arises from HBV as a result of several changes to liver cells (and, as we find out in the new research, many other cells) at the genetic level. In addition, the damage caused by the virus leads to reactive oxygen species which causes damage to the DNA and leads to the transformation of some hepatocytes into cancer.
The dangers of hepatitis B is clear. Although all vaccine-preventable diseases are dangerous, that’s why we have vaccines in the first place, hepatitis B is one of the scariest.
The best way to prevent an HBV infection is with the hepatitis B vaccine, which can last for over 20 years (pdf), giving protection to the child as they enter adulthood. Then, adults can receive the vaccine again, especially if they have risk factors, like being a healthcare worker.
There are some treatments for HBV that require taking daily medications for a year or more. And if that isn’t effective, second-line daily treatments, also requiring a year or more, may be employed. These are expensive drugs.
Of course, since many individuals are asymptomatic, those individuals may not seek any treatment which will lead to higher risks of many cancers. The old adage, “a gram of prevention is worth a kilogram of cure” (or an “ounce of prevention is worth a pound of cure” for those barbarians who refuse to use the metric system), makes perfect sense – the HBV vaccine prevention is so much more valuable than the risk of the HBV infection.
Despite these facts, the anti-vaccine religion wants to convince us that the vaccine is unnecessary. They claim that only sex addicts and drug abusers can contract the disease – although hepatitis B infections are frequent in those individuals, it’s ridiculous to believe that that’s the only way to contract the infection.
The hepatitis B virus can be transmitted through casual sex with a partner who may not know they have the disease. A cheating spouse (yes, I’m a cynic) could transmit the disease unknowingly to the mother. Healthcare workers who are exposed to blood may contract it. In fact, there are several innocent modes of transmission of the virus that do not include chronic sex or drug use.
The anti-vaxxers have labeled the HBV vaccine as an “STD vaccine,” but that’s just a strawman argument, without any basis in scientific fact. As Vincent Iannelli, MD writes in his Vaxopedia blog:
Of the 40,000 newly infected people with hepatitis B each year, there are thought to be up to 950 infants who develop chronic hepatitis B from an untreated perinatal hepatitis B virus exposure. Even if it is more rare than that, skipping or delaying the birth dose of hepatitis B vaccine is an unnecessary risk.
And it is absurd to think that all of those 950 infants are born to drug-abusing, promiscuous mothers. As we mentioned above, many HBV infections are asymptomatic, which can still be passed onto the newborn. But more than that, the baby can be exposed to the virus any time for the next 20 years, but they’re protected from the dangerous disease.
Of course, this all makes sense to me.
Cancer surgery or the hepatitis B vaccine. Easy choice. Photo by Olga Guryanova on Unsplash
New hepatitis B virus paper
As I wrote above, the role of hepatitis B virus in certain forms of liver cancer is clear. But a new paper, published in the peer-reviewed, high impact factor journal, JAMA Network Open, determined that HBV may be linked to several other non-hepatic malignancies such as oropharyngeal, pancreatic, stomach, lymphatic, and colorectal cancers.
The researchers analyzed data in a cohort study, an epidemiological study that ranks near the top of the hierarchy of biomedical research, of nearly 500,000 individuals in China. The researchers identified 15,355 HBV-seropositive (based on HBV DNA in the tissues) individuals in the group. After 4.4 million person-years of follow up, the researchers found the following hazard ratios (HR) for cancers in seropositive versus seronegative individuals:
- Hepatocellular carcinoma – HR = 15.77, or a 1577% higher risk for this type of cancer in HBV positive individuals.
- Lymphoma – HR = 2.10
- Pancreatic cancer – HR = 1.65
- Oral cancer – HR = 1.58
- Colorectal cancer – HR = 1.42
- Stomach cancer – HR = 1.41
This study coincides with an earlier study, in 18 US-based academic and community oncology centers, that showed that a substantial number of individuals newly-diagnosed with several cancers were unaware that they had an HBV infection.
The authors concluded that:
This study found that HBV infection was also associated with the risk of nonliver cancer, especially digestive system cancers among adults in China.
Of course, there are some limitations to the study. First, it involves only one ethnic and national group of individuals, so there may be other confounding factors that could influence the results. Second, the authors mentioned that there may be a small number of false negatives in testing for HBV that could influence the results.
This study will need to be repeated in a larger, more diverse population, across the world to confirm the results.
Years of medication to treat hepatitis B. The HBV vaccine is so much easier. Photo by Andrés De Armas on Unsplash
Summary
This study clearly shows that the hepatitis B virus is much more dangerous than originally thought, and just being linked to liver cancers was pretty bad enough. This means that the hepatitis B vaccine is as much of a cancer-preventing vaccine as the HPV vaccine.
Despite the awful tropes, lies, and misinformation of the anti-vaxxer FUD, hepatitis B is an extremely dangerous disease. Why on earth would anyone avoid preventing the disease?
Of course, who amongst us understands the mind of a science-denying anti-vaxxer?
Citations
- Ramsey SD, Unger JM, Baker LH, Little RF, Loomba R, Hwang JP, Chugh R, Konerman MA, Arnold K, Menter AR, Thomas E, Michels RM, Jorgensen CW, Burton GV, Bhadkamkar NA, Hershman DL. Prevalence of Hepatitis B Virus, Hepatitis C Virus, and HIV Infection Among Patients With Newly Diagnosed Cancer From Academic and Community Oncology Practices. JAMA Oncol. 2019 Jan 17;. doi: 10.1001/jamaoncol.2018.6437. [Epub ahead of print] PubMed PMID: 30653226; PubMed Central PMCID: PMC6459217.
- Song C, Lv J, Liu Y, Chen JG, Ge Z, Zhu J, Dai J, Du LB, Yu C, Guo Y, Bian Z, Yang L, Chen Y, Chen Z, Liu J, Jiang J, Zhu L, Zhai X, Jiang Y, Ma H, Jin G, Shen H, Li L, Hu Z. Associations Between Hepatitis B Virus Infection and Risk of All Cancer Types. JAMA Netw Open. 2019 Jun 5;2(6):e195718. doi: 10.1001/jamanetworkopen.2019.5718. PubMed PMID: 31199446.
