Immunize with care

Japanese Encephalitis vaccine

By Tharuka Dissanaike

A large scale pro gramme to immu nize children against the dreaded Japanese encephalitis is on right now. Many schools and clinics have been involved in the campaign to curb the disease in the young through MOH offices spread throughout the western province. The vaccination -aimed at children under 10 years of age- is administered in two doses with boosters coming in one year and three years afterwards.

But questions have arisen about the way the immunization effort is organised. Especially taking into consideration the number of contraindications for the vaccine and the amount of precaution required in certain cases where the children are at risk of developing serious complications. Especially after the vaccination programme was spread through the entire western province, questions arose whether the risk of encephalitis in the province warranted the kind of mass scale immunization which is being carried out- at the cost of certain serious side effects to the children.

The Epidemiological Unit of the Ministry of Health insists that the vaccination is necessary and that it has contributed to a marked reduction of people falling prey to the virus.

In 1985 when the disease first rose to epidemic proportions in Sri Lanka 441 cases were reported and 66 of these died. But last year, after nearly a decade of immunizing children against Japanese Encephalitis the number of reported cases came down to 138 with 17 deaths.

The disease primarily affects children in the 1-14 age group. Of the 307 cases of JE reported in 1996, nearly 35 percent were young children. “Roughly one third of children who get JE die, and a third will end up with disabilities. One third will recover fully,” a senior paediatrician said.

The Epidemiological Unit said that this is why children under ten were chosen as the primary target group.

The vaccination is totally government sponsored. Vaccines are imported from Japan at a cost of Rs. 65 a dose. Each child should have four doses. Added to this is the cost of syringes, sterilisation, storage and transportation.

The total number of doses for 1998 imported by State Pharmaceuticals Corporation from Denka Seiken of Japan is 1.5 million at a cost of over Rs.90 million.

Side effects to the vaccine include high fever, local oedema, swelling, pain and even seizures and rashes. In 1994, before the drug was introduced to the entire western province, an analysis of the side effects was done by the Epidemiological Unit. At the time 119 cases were reported to have significant side effects of which 91 were from Gampaha district where the drug was recently introduced.

The majority developed fever and 38 suffered from rashes. Thirteen children developed neurological seizures. No deaths were reported. Dr. T.A. Kulatilaka of the Epidemiological Unit says that incidence of side effects was lower that year than in 1993.

Lady Ridgeway Hospital has recorded one death - a transfer from Kalutara Hospital- of a child who developed continuous convulsions after the drug was administered. This was within the last two years, when the drug was introduced to the entire western province. “The benefits of the vaccine far outweighs the side effects,” Director, Epidemiological Unit, Dr. Jayakuru said. “These are not experiments that we are doing. These vaccines are tested and proven to be effective.”

SPC Chairman Prof. Colvin Goonerathne dismissed that there could be any doubt about the vaccine itself. “It is no more dangerous than any other vaccination.”

Prof. Goonerathne said that the government’s decision to carry out vaccination despite the tremendous expense is due to the human cost of JE. “Besides deaths, a large number of people end up mentally disabled and epileptic. This is a tremendous burden to society.”

The Director of the Lady Ridgeway Hospital, Dr. Wimal Jayantha in a slightly differing viewpoint said that while the disease is best prevented, necessary care has to be taken so that severe side effects are minimised.

He said that the drug has a high level of contraindications. This means that clinics and schools must be properly prepared to administer the vaccine. Dr. Jayantha said that if a child suffers from convulsions or goes into anaphylactic shock due to the vaccine proper medical care must be available to deal with it.

He said that he refrained from vaccinating his seven year old twins, since they show allergic reaction to certain food types. “I feel that the risk of their acquiring JE is less that the risk of vaccinating them- knowing the contraindications.”

Dr. Jayantha said that a better public awareness campaign should have been carried out before the vaccination was started so that parents as well as medical staff were fully aware of the advantages and dangers of the drug.

Dr. Jayakuru said that a certain risk is there in any vaccine. She said the number of patients with side effects is no cause for alarm. She observed that any vaccination programme becomes an issue in the western province. “We will soon have to ask the patient to sign a document of consent for vaccination if so many questions arise,” she said. “When we first started immunizing against JE in Anuradhapura and Polonnaruwa in 1988 bus loads came from other provinces to obtain the vaccine. They knew of the dangers of the disease.”

Japanese Encephalitis was first detected in Sri Lanka in 1968. It was rampant in the dry zone areas where the carrier Culex mosquito bred in rice fields. Almost 800 cases were reported in 1987 when JE assumed epidemic proportions. Vaccinations were started in risk areas in 1988. Later the disease spread to Kurunegala, Batticaloa and Gampaha districts. Immunization programmes were initiated when a high number ofcases were reported from a district.

More Plus