Whooping cough is a major problem in Sweden, with epidemics peaking every three years in the nation's children.

Proponents of childhood vaccines would argue that this is because the country stopped vaccinating its children in 1979, but it did so for very good reasons. Epidemics started during the 1970s, when 90 per centof Swedish children were being vaccinated with a whole-cell version of the pertussis vaccine. Production of the vaccine had changed and had become less efficacious because earlier versions came with unacceptable adverse reactions.

Now researchers believe they have finally cracked the dilemma by using an acellular vaccine, with the pertussis toxin inactivated by hydrogen peroxide, which they believe is safer and more effective than the whole-cell variety.

They inoculated two groups of infants, one with a "placebo" a diphtheria and tetanus shot and the other with the new acellular pertussis vaccine.

Researchers from Goteborg University reported "no serious reactions" to either vaccine. However, two of the 1,724 infants inoculated suffered febrile convulsions within 48 hours, one child died, four children had bacterial infections, and malignant diseases developed in five others!

A similar medical double-speak was achieved when assessing the efficacy of the new vaccine. The researchers concluded that it offers "substantial" protection. The infants were each given a course of three shots; despite this, 321 of them went on to develop whooping cough. Researchers claim the vaccine to be 71 per cent efficacious, although this fell to just 55 per cent after the second shot. In other words, it is only half effective (New Eng J Med, October 19, 1995).

The US may soon switch to a more benign version of the polio vaccination. Health officials are concerned that the current vaccine is causing eight to 10 cases of paralytic polio every year at a time when polio supposedly has been eradicated in the US.

The Advisory Committee on Immunization Practices has recommended a change to vaccinations of inactivated polio vaccine (IPV), which would be administered at two and four months of age, followed by oral vaccine at either six months and 12 to 18 months, or 12 to 18 months and four to six years. They believe that the change will halve the number of serious reactions.

The recommendations have to be endorsed by the Centers for Disease Control (The Lancet, October 28, 1995).