Why Do Newborns Need the Hepatitis B Vaccine?

The first vaccine a baby receives — within hours or days of birth — protects them from hepatitis B virus (HBV). In a lot of people’s minds, HBV is associated with drug use and sexual activity — which stigmatizes people who have been infected with HBV or are carriers of the virus. Unfortunately, this stigma causes a lot of people to question why babies even need to be vaccinated against it, often pointing to “Big Pharma” conspiracy theories. A lot of other people are put off by the misconception that the HBV vaccine is made with human blood (it’s not).

May is Hepatitis Awareness Month, a time to learn about a childhood vaccine that’s saved millions of lives.

There are perfectly good reasons to vaccinate babies against HBV, mainly that HBV is the leading cause of liver cancer, itself one of the Top 10 types of cancer worldwide. Nine out of 10 infants born to a mother who is an HBV carrier will develop chronic infections and become carriers themselves — and a quarter of them will die prematurely of liver disease. Babies who develop chronic HBV infections are 63 times more likely to develop liver cancer than non-carriers, a connection that is 2 to 3 times stronger than the link between smoking and lung cancer.

When it comes to HBV, age at infection matters. Most people with chronic HBV infections are exposed at birth or in early childhood, when they are most likely to develop chronic, lifelong infections — whereas only 2 to 6 percent of infected adults will develop chronic infections, with only 15 percent of them eventually dying from liver disease. The fact that chronic infection risk is inversely correlated with age at infection means that birth is the time when a child is the most vulnerable to this virus — hence the importance of vaccinating as early as possible. Continue reading

AIDS Denialism: Conspiracy Theories Can Kill

This scanning electron micrograph from 1989 reveals HIV particles (colored green) emerging from an infected cell. Image: CDC’s C. Goldsmith, P. Feorino, E.L. Palmer, W.R. McManus

We’ve all heard various conspiracy theories; we may or may not find them credible, and we might chalk up opposing viewpoints to simple differences in opinion. Sometimes, however, conspiratorial narratives are woven around matters of life and death — and in such cases, the spread of such ideas can influence dangerous changes in behavior and even government policy.

AIDS denialism is based on the idea that human immunodeficiency virus (HIV) does not cause AIDS. Although the existence of HIV and its causal connection to AIDS has been thoroughly demonstrated by scientists, denialists either reject the existence of HIV altogether, or cast it as a harmless virus that doesn’t cause illness. Denialism often relies upon rhetorical strategies that are superficially convincing but intellectually hollow, including the cherry-picking of evidence, appeals to unreliable “experts,” and untestable claims. Denialists also might cite early AIDS research from the mid-1980s while ignoring more up-to-date findings and improved medical procedures. Such rhetoric creates a sense of legitimate debate in an area where there is none, and the only new evidence welcomed into the discourse is that which confirms preconceived notions.

Health decisions must be shaped by the best available evidence, and when denialism misinforms, one cannot make an informed decision.

If AIDS isn’t caused by HIV, what do denialists claim is behind the unique symptoms that characterize it? Some say that conditions such as malnutrition, or diseases that have been around for a long time, are simply being labeled as AIDS. Other denialists cast antiretroviral drugs as the cause, rather than the preventive treatment, of AIDS. Some claim that AIDS is caused by behavior, such as drug use or promiscuity — with some even saying that an accumulation of semen in the anus can cause AIDS. None of the claims is true — while AIDS can leave someone vulnerable to a wide variety of diseases, and while sharing IV equipment and engaging in unprotected sex can increase risk, there is only one cause: HIV. Continue reading