Sri Lanka’s immunisation program best in South East Asia :

Rubella vaccine’s safety assured

As the country’s r ubella vaccination scandal of two deaths worries Sri Lankans on immunising their children, the country’s Epidemiology Unit of the Family Health Bureau is working around the clock to produce a WHO (World Health Organisation) report about the real cause of it.

Consultant Epidemiologist at the Unit, Dr. Virginie Malawaarachchi said, “We, at the Epidemiological Unit and the Health Ministry feel upset over the death of 13-year old Asanthi Wasana recently but if we don’t immunise our children, the consequences later would be deadlier”.

The Epidemiology Unit’s Immunisation handbook mentions that vaccines used in the national immunisation programs are extremely safe and effective. But no vaccine is perfectly safe and adverse events can occur following immunisation. In addition to the vaccines themselves, the process of immunisation is a potential source of adverse events. An adverse event following immunisation (AEFI) is any adverse event that is believed to be caused by immunisation.

“In the case of 12-year old Peshala Hansini who died on March 19, she had a severe case of anaphylaxis,” said Dr. Malawaarachchi.

The emphasis should be placed on the fact that Cognitive Rubella is very severe and it is imperative that we prevent it with the simple vaccination. Congenital rubella syndrome (CRS) can occur in a developing foetus of a pregnant woman who has contracted rubella during her first trimester.

Infection

If infection occurs 0-28 days before conception, there is a 43 per cent chance the infant will be affected. If the infection occurs 0-12 weeks after conception, there is a 51 per cent chance the infant will be affected.

The classic triad for congenital rubella syndrome is Sensorineural deafness - (58 per cent of patients), Eye abnormalities - especially cataract and microphthalmia (43% of patients) and Congenital heart disease - especially patent ductus arteriosus (50% of patients). Other manifestations of CRS may include spleen, liver or bone marrow problems (some of which may disappear shortly after birth), mental retardation, small head size (microcephaly), eye defects, low birth weight, thrombocytopenia purpura (presents as a characteristic blueberry muffin rash), hepatomegaly and micrognathia.

Children who have been exposed to rubella in the womb should also be watched closely as they age for any indication of developmental delay, schizophrenia, growth retardation, learning disabilities, diabetes and glaucoma.

“We have a good policy to immunise children which is why our infant mortality rate is 11 per cent for every 1000 live births” said the doctor. However, when Sri Lankan medical experts thought that there were side effects with the DPT-HBV-HIB (Pentavalent vaccine), it was stopped. “After a thorough investigation by two international groups on the Hib vaccination, we discovered that there was no link to long-term side effects but it would have been a natural reaction to the drug,” said Dr. Malawaarachchi.

Health and Nutrition Minister Nimal Siripala de Silva has said Sri Lanka should not give up rubella vaccination, part of the National Immunisation Programme, just because two children died from the more than one million who had been already vaccinated this year. The WHO has informed that no death has been reported in any other country through rubella vaccination.

Health funds

Without a good immunisation program, the incidence of diseases would be high which would severely affect the national health sector. “Not only the people who have sick children will suffer but health funds will have to provide treatment which would have been easy to prevent with immunisation” said Dr. Malawaarachchi. In any event, the Health Ministry always takes the blame. “The problem is that people think about the negative aspects so much that this blinds them to the positive reality,” said the doctor. The Consultant Epidemiologist said minor cases are sensationalised when the positive results are basically unheard of.

“In the past, we have been successful in eradicating diseases like polio, pertussis, neonatal tetanus, diphtheria, measles and tetanus” said Dr. Malawaraachchi. As a result of successful immunisation programs in Sri Lanka, the last case of polio was recorded in 1993. Diphtheria no longer existed after 1985. By 2004, nearly 100 per cent of all pregnant women were immunized against neonatal tetanus as in the case of tetanus where hardly any case surfaced recently.

Further the doctor commented, “In making sure other countries follow the policy, the polio eradication year was extended from 2000 to 2005 but there are cases even today in Afghanistan and some African countries”.

However, people should realise that despite allegations, we should not hold back the Immunisation Program, otherwise it will be too late to save the many who might suffer as a result.

The investigation done by the National Advisory Committee on Adverse Events Following Immunisation is due soon and then only will we know the actual reason why Asanthi died.

-ND

History of Immunisation in Sri Lanka

 Vaccination against smallpox

1949:   BCG vaccination for adults
1961:   Introduction of “Triple” vaccine
1962:   Introduction of Oral Polio Vaccine
1963:   BCG vaccination for newborns
1969:   Tetanus Toxoid for pregnant mothers
1978:   Launching of the EPI
1984:   Introduction of Measles vaccine
1989:   Achievement of UCI status
1991:   Introduction of TT 5 dose schedule for pregnant mothers
1995:   Launching of NIDs to eradicate polio
1996:   Introduction of Rubella vaccine
2000:   NIDs to SNIDs
2001:   Introduction to new immunization schedule
2003:   Introduction of HBV
2008:   Introduction of Hib Pentavalent Vaccine

(Courtesy : Sri Lanka Epidemiological Unit)