Vaccination at birth

An ounce of hepatitis-B vaccine is worth a pound of cure

By DONG A. DELOS REYES, CONTRIBUTING EDITOR

Hepatitis B claims 330,000 lives in its yearly harvest of deaths throughout the Western Pacific region-that's about 890 deaths in a day, nearly the same as tuberculosis, which is one of the Philippines' top three killer diseases. An estimated 160 million people are chronic carriers of the virus and 15 to 25 percent of them will die from either cirrhosis or liver cancer.

    The region accounts for more than 50 percent of the total global mortality and 45 percent of the global disease burden-with the Philippines turning up the highest proportion of the region's chronic infection.

    Even so, health professionals expect the deadly demographic to be pruned. World Health Organization representative to the Philippines Dr. Jean-Marc Olivé maintains that hepatitis B is not exactly an infectious disease as it appears much later-assaults virus carriers as they turn 60 years old-and runs its course turning up as cirrhosis or liver cancer.

    The virus is transmitted from pregnant mother to child in utero or at childbirth, through unprotected sex with a chronic carrier, or via blood transfusion or intravenous use of drugs. However, the earlier the virus is contracted, the deadlier it is for the infected individual- thus, newborn children are zeroed in as primary targets of prevention to curb the spread of the disease and haul down mortality rates.

    Olivé cites the Taiwan experience as a success story. The vaccine was introduced in 1984 to children born to infected mothers. By 1986, vaccination was carried out on all children.

    "The peak prevalence of hepatocar-cinoma is at 60 years old. The [liver-cancer] incidence in children six to 14 years and the mortality rate is about 0.78 [and] 10 years after the vaccine's introduction, the incidence is reduced to 0.38; that is already a drastic reduction," he related.

    In mounting a workable preventive strategy Olivé said that "the first goal to reach 8.8- percent seroprevalence to less than one percent is to get 80-percent coverage for one dose at birth of hepatitis B. Then, over 80- and ideally 95-percent coverage before the child reaches one year of age or as soon as possible."

    After the vaccine was introduced in 2000, coverage in the Western Pacific region is at about 70 percent with China taking up the slack, he disclosed.

    The Philippines is still in the blue-a hepatitis-B hotspot-as the coverage is less than 80 percent. Also, full supply of the vaccine has only been achieved recently as suppliers have not been able to provide requirements in the last 10 years.

    "We know that very well because there was not enough supply of vaccines purchased by the government," he added, citing instances in which health workers were having difficulty opening a vial of vaccine due to apprehensions that they will have a vaccine shortage.

    For another, just over 50 percent of all births in the country have an attending health professional that accounts for less-than-high coverage with three doses of the vaccine.

    There are high rates of mother-to-child or perinatal transmission of the virus that require a high birth dose. The mother-to-child transmission account for about 30 to 40 percent of all new infections-90 percent of the infected infants will likely become carriers, he cited.

    There is the add-on advantage of giving the vaccine's birth dose within 24 hours. If 50 percent of births were vaccinated, reduction can be improved by about 10 percent. Reaching 90-percent coverage would be extremely difficult in the Philippines but that would translate to 84-percent reduction compared with the 68-percent without the birth dose, Olivé averred.

    "We should advocate to parents whenever they deliver that their children be vaccinated, that the vaccine be available in maternity wards and lying-in clinics," he stressed.

    On a more optimistic note, Olivé reported that the Department of Health has secured 100-percent of the country's vaccine needs for 2006 and 2007 while the Senate has set aside appropriations for 100-percent vaccine requirements through 2010. M