Swine flu shots important before peak season, say experts

By Dr. Ananya Mandal, MDApr 15 2010

According to reports only 13% of the adult population in Singapore has a natural immunity to H1N1 influenza or influenza A. Communicable Disease Centre (CDC) clinical director Leo Yee Sin led this research and emphasized on the importance of vaccinations with the new three in one vaccines in case of a return of the disease.

This study tested blood samples from about 2,900 adults before, during and after the H1N1 epidemic last year (June to October) - found that fewer than 400 were immune to the virus. Associate Professor Leo also said that children were not a part of this study and they are at a higher risk of the disease.

The new three in one vaccine will be available later this month. The experts say that the old vaccines do not work well against new circulating influenza strains. Professor Sin said, “Unfortunately, old vaccinations cannot protect against potential circulating new strains and that's why we have a new composition in the coming vaccine production…The coming vaccine production, the composition is exactly the same as the year-end production, so in other words, we have a good long time period for people to consider to go for vaccination.” This year the pandemic H1N1 virus, a new H3N2 strain, and Influenza Type B are expected to be predominant strains for the coming flu season. A

According to the Health Ministry about 430,000 of the 1.3 million doses of pandemic H1N1 vaccine have been taken up. Since H1N1 continues to circulate globally, such vaccines will still be useful. Earlier this month Health Minister Khaw Boon Wan also lowered prices of the pandemic H1N1 vaccine early this month, to S$8 per dose for new orders, compared to the original cost of more than S$20.

Professor Leo also said, “This is a constant challenge when we look at the influenza vaccine, and for that reason, we have two times a year in vaccine recommendation because of the change in the circulating strains and also the change in immunity we anticipate in a population.” The influenza peak season is usually in May or June and this is higher than the winter peak and thus most should get vaccinated before the season. Reports also suggest that only 6% get themselves vaccinated.

In other Swine flu news, in Kuala Lumpur the Health Ministry has also decided on setting up isolation rooms for those with influenza-like illness (ILI) following the rise in the number of ILI cluster cases involving schoolchildren. There has been a report of seven new cases and most of them were school kids. Director-General of Health Tan Sri Dr Ismail Merican said these children “must be isolated until they fully recover.” He said, “Almost all the children were treated as outpatients and isolated in their homes or hostels.” The laboratory results confirming the illness from throat swabs is yet to be revealed. Six of these children are in the intensive care units. He said the onus of prevention of spread was with the parents and primary care givers, “I want all parents, teachers, school heads and hostel wardens to monitor the health of the children every day so that early measures can be taken and put in place as per the guidelines issued by the ministry…We have been stressing on the preventive measures since April last year, but there are still people who are complacent and take the H1N1 pandemic lightly…The disease, if not treated early, can cause complications and death, especially for those in the high-risk group.”