Kirk Thame, Contributor

For years, workers in the medical field have looked for a more effective way to tackle gastroenteritis. A seemingly simple disease, gastroenteritis each year results in over two million hospitalisations and more than 875,000 deaths worldwide.

No country is spared, such that almost all children will be affected by age five. Even industrialised countries with excellent water supplies and public health strategies have been unable to effect a decrease in the incidence of gastroenteritis in recent times.

The scientific community has focused on developing a vaccine against rotavirus - the commonest cause of gastroenteritis (especially cases that are severe enough to require hospitalisation). The first rotavirus vaccine was released in 1998 but, within a year, an association with intussusception (a type of intestinal blockage) was noted. This resulted in the vaccine being withdrawn.

Gastroenteritis remained a problem, and the bar had been raised for future rotavirus vaccines to prove themselves safe and effective. Two pharmaceutical companies took up the challenge to produce vaccines and in January 2006, the New England Medical Journal published clinical trials showing both vaccines to be efficacious and safe.

How do these vaccines work?

The vaccines mimic what happens in nature. After exposure to the virus two or three times, the body becomes immune to it (much like infections with viruses such as chicken pox or measles). Most people are immune by the age of five and have no symptoms in adulthood due to rotavirus. During these exposures, though, the child is at risk for dehydration and death.

The vaccine exposes the body to a harmless strain of the virus, allowing the body to build immunity to it without the person ever getting sick. Vaccinated individuals would have either no symptoms or very mild symptoms if they come in contact with the virus.

Is it worth it?

The true worth of the vaccine would be seen through the eyes of those who have been affected by the disease. Apart from the complications of hospitalisation and death, the disease itself is unpleasant and leads to days away from school and work. It has a significant financial impact on the family and workforce.

Who should be vaccinated?

The vaccines are given to infants up to six months of age. The greatest risk for dehydration and death is in children less than two years. Older children and adults, as discussed before, are usually immune and would not benefit from vaccination. In all of the studies performed so far the required doses were completed by six months. New studies would be needed to prove the vaccines both safe and effective for children older than six months but still at risk for significant infection.

Is it really safe?

The studies showed no increase risks in infants who received the vaccine when compared to infants who did not. Over 60,000 infants had to be enrolled to prove that there would be no risk of intussusception. The vaccine is given by mouth so the baby gets no extra sticks.

How can my child get this vaccine?

Only one of the two licensed vaccines is presently available in Jamaica. It may be obtained through paediatricians and general practitioners.