Of all the vaccines in a child’s repertoire, perhaps the most controversial is the vaccine against Hepatitis B virus. It’s not because of concerns about the vaccine’s safety necessarily; parents tend to be more worried about the MMR vaccine, since that has received so much press. But many parents feel that the HBV vaccine is unnecessary. HBV is transmitted primarily via exposure to blood or other body fluids, or by sexual transmission. Because they assume their kids will be smart, stay away from drugs, and not have sex with the “wrong” people, they assert that the vaccine is a waste and an unnecessary risk for their children. However, recent research suggests that there is reason to be extra cautious, describing HBV transmission between dental patients.
The investigation began when a 60-year-old woman (I’ll call her patient X) was diagnosed with Hepatitis B infection. She didn’t have any of the risk factors for acquisition–no drug use, no sex for many years–so they began an investigation in order to determine just how she became infected with the virus. The one thing she did mention was having oral surgery several months prior, so investigators looked into patients who’d had oral surgery in the same clinic at the same time as the woman. They then cross-checked those patients against the Department of Health’s Hepatitis B registry, and found a match to a patient who’d had surgery the same morning as the index case (I’ll refer to her as Patient Y). A portion of the viral DNA was sequenced and found to match, suggesting they were very closely related (and supporting the hypothesis that Patient X was infected by Patient Y).
48 other patients had surgery in that same week at the facility; 27 of them following the source case, and blood samples were obtained from 25 of them. Luckily, many of these patients (64%) had been fully vaccinated already for HBV. No other cases were identified.
What’s most worrisome is that the investigators couldn’t work out exactly how the virus was transmitted. As far as they could tell, normal infection control practices were adhered to. Tools were autoclaved, hands were washed, the office was regularly cleaned and potentially exposed surfaces were disinfected. So how did the virus infect Patient X? They don’t know.
Now, granted, this is an unusual case–enough so to have been written up and submitted as a novel paper. It’s very unlikely that anyone reading would actually contract HBV from a procedure at their doctor, or dentist, or even tattoo artist, as long as all were following proper infection control procedures. But the fact is, one just never knows, and as the vaccine is safe and available, why not protect your kids? Even if you believe your little Timmy and Suzy are perfect angels and would never touch drugs or have sex with someone who might be infected, having them vaccinated protects them in case they make life decisions that mom and dad may frown upon–and also protects them from freak occurrences such as the one described above.
Redd et al. 2007. Patient-to-Patient Transmission of Hepatitis B Virus Associated with Oral Surgery. 195:1311-1314. Link.