UNDER THE MICROSCOPE
The Philippines has one of the highest hepatitis B (HBV) burdens in the world, with 16.7 percent of Filipinos positive for the virus with over 7.27 million affected. It means we are a hyperendemic country for HBV. Another 40 percent have serological markers (anti-HBs and anti-HBc) present indicating they have been exposed and have recovered from hepatitis B.
My experience in a major hospital performing hepatitis B serology some 30 years ago is consistent with current epidemiology. Then, 15 percent of those tested were HBSAg positive (chronic carriers), asymptomatic but may develop cirrhosis or liver cancer. Another 60 percent were positive for anti-HBs and anti-HBc, indicating prior exposure and recovery. These figures are not far from the current situation despite the hepatitis B immunization program of the DOH.
Taiwan has successfully lowered its prevalence of chronic HBV infection by more than 90 percent with universal HBV vaccination. Our figures have not budged far from three decades ago despite having HBV vaccinations for newborns since 2007 to prevent mother-to-child transmission.
The majority of HBV infections are acquired by the newborn baby from the mother during delivery, exposed to maternal blood and body fluids. Nowadays, pregnant women are screened for HBV infection, and if positive, the baby is immediately given HBV vaccine and HBV immunoglobulin to prevent lifelong infections. Those women who are negative for HBV will have their newborn babies given HBV vaccine only.
This is very important to reduce and ultimately eliminate HBV as a public health problem. Ninety percent of infants exposed at birth and not given HBV vaccine and immunoglobulin will become chronic carriers. Those one to five years old have a 30-50 percent rate of becoming carriers. Less than five percent of adults become carriers. It is clear that the key to reducing national hepatitis B burden is through newborn vaccination. Otherwise, the cycle of infection will not be broken.
But the DOH is also requiring health workers in the clinical laboratories to have hepatitis B vaccination regardless of serologic status. Note that this is mandatory and if some of your laboratory staff are not vaccinated, they will not issue a license to operate.
While it is admirable to endeavor to reduce HBV infections, it seems those who conceived this requirement do not understand the epidemiology of HBV. If 65-75 percent of Filipinos are either HBV carriers or are recovered from HBV infection, this requirement represents a poor use of resources that will not significantly alter the epidemiology of HBV in the country. Even those infected as adults will recover spontaneously in 95 percent of cases.
What’s even more galling is that it will require even those who are non-responders to HBV vaccine (5-15 percent of healthy adults fail to develop protective antibodies after the three-dose HBV vaccination). I myself am a non-responder and time and again, I am asked to have HBV vaccinations which will not change my serologic status. Seniors like me are also not likely to respond adequately to HBV vaccination with the attendant risks, no matter how small, of adverse vaccine reaction. I would rather risk HBV infection but the odds are low for that, since HBV is transmitted via blood/body fluids. There are measures to prevent HBV infection such as blood screening and abstaining from risky sex and drug injection use.
Even more insane is the requirement to have annual HBV serologic titers to confirm the level of protection from HBV. While the test can show that one has acquired immunity (anti-HBs of 10 mIU/ml), the titers may wane over time but it doesn’t mean you are no longer protected from HBV infection. The body, if challenged by introduction of HBV into the bloodstream, will rapidly ramp up production of antibodies against HBV which will prevent infection (anamnestic response). Why bother repeating the titers?
It is a waste of resources to keep asking for HBV vaccination and antibody titers for laboratory workers especially considering that these measures are a financial drain on hospitals and will achieve no significant benefits. Besides, we practice universal precautions, where medical technologists wear gloves, googles and lab gowns to prevent contamination from samples. Immunoglobulin injection can prevent HBV infection from exposure is available in case of needlestick injuries or eye splashes for the non-immune.
Considering the 15 percent HBV carrier rate, there will be a sizable number of lab staff who will be positive and will not respond to HBV vaccines, no matter how many times it is given. Will he/she be not allowed to work in that profession? If they are barred from working, it is an unconstitutional act that can and should be challenged in court.
My appeal to the DOH is to reconsider this issue based on epidemiology and immunology science. The argument for mandatory HBV vaccination for health professionals falls apart on scientific and legal grounds. Calling Dr. Ted Herbosa!
