HKU Bulletin November 2006 (Vol. 8 No. 1)

7 Do You Understand? Teaching vulnerable populations about disease prevention. W ith the threat of avian flu looming over Asia and fears that we might see a re-emergence of Severe Acute Respiratory Syndrome (SARS) there has been a clear need to educate vulnerable populations about disease avoidance. With this in mind Professor Terry Au, Chair Professor of Psychology, conducted two studies recently – one in primary schools, the other in elderly homes – to teach cold and flu prevention. “I thought it would be interesting to see how much biology third and fourth-grade children can learn and I wanted to get them thinking about infectious diseases, like colds and flu but also SARS and avian flu,” said Au. “The starting point came because I was not very happy with the general health education – it’s a laundry list of do’s and don’t, which is very boring and hard to keep track of. Sometimes people don’t understand the rationale behind the instructions. And the general finding in psychology is that if you don’t understand something it’s very hard to follow. “So the nagging do’s and don’ts approach is not very effective. People in general are very interested in ‘why’ and ‘how’ and that’s especially true for young children. I wanted to appeal to people’s natural curiosity to get them to think about why and how we get sick - getting them to understand why some behaviours are safe and some are not. We taught them very simple biology.” Au’s approach was developed in Los Angeles where she taught children about HIV Aids prevention. “I chose to pursue cold and flu prevention in Hong Kong because it’s easier to observe the change in children’s behaviours,” she said. Soon after SARS, Au sent her team into a number of schools to see if children were engaging in preventive behaviour. What they saw was misunderstanding of the do’s and don’ts. “They were going through the motions without understanding why. There was a lot of emphasis on washing your hands frequently, but from a young child’s point of view it’s not clear what frequently means – three times a day or once a minute. “What was most worrisome was that they wore masks for the whole day, but took them off for PE lessons. These masks were highly contaminated, and taking off them contaminated the children’s hands, and then in PE they would throw a ball to each other which also became contaminated and so on.” So Au and her team took her Think Biology course into two local schools and got up to 40 children to imagine the flu virus being alive and in the environment. “We told them that the virus can stay alive outside the body for several hours, so there’s a big window of opportunity to pick it up. We taught them about the point of entry – the eyes, nose and mouth and we taught them the biology and how we can kill the virus, by using disinfectant or hot water. So hot cooked food is safer, and using alcohol or bleach solution to wipe down things, and wash your hands, is safer.” Then she tested the children by showing them video clips and asking them to spot anyone engaging in risky behaviour. “Children who went through the Think Biology course had better detection than those in the control group. They were also better at explaining why certain behaviours are risky. “What was most encouraging was that when they were tested individually, by being asked to handle food, they spontaneously cleaned their hands first. In both schools the team found that the pupils’ understanding of detecting bad behaviour had increased. She took the same course into elderly nursing homes and achieved similar results. “We now hope that this knowledge can be activated if avian flu hits Hong Kong,” said Au. 6 RESEARCH Children at Risk H ong Kong’s worsening air quality has been implicated in a whole host of medical conditions but now scientists have shown that children with asthma are particularly at risk. In tracking schoolchildren for six years researchers in the Department of Paediatrics and Adolescent Medicine, found a significant increase in the prevalence of severe asthma symptoms in six and seven year-olds. Further research on daily hospital admissions and outdoor pollution levels revealed a spike in the number of admissions for severe asthma attacks on the days when the levels of pollutants such as nitrogen dioxide, ozone and particulates were especially bad. This is the first study to show a significant association between the two. Chair of Paediatrics Professor Lau Yu Lung, who led the team, said: “Although the impact of the study appears to be small, the risk implied to the whole population is substantial.” During the six-year period, the average daily admission count for asthma in children was around 12. Increased levels of air pollution, however, raised those admission by 13 per cent. Children are particularly vulnerable to environmental pulmonary toxins because they have an immature immune system and their bodies are less efficient at detoxifying pollution. They are also more active, more likely to play outdoors and have smaller peripheral airways. Add to this the fact that children are prone to breathing through their mouths rather than their noses – thanks to large adenoids and tonsils – and they become particularly vulnerable. Although no threshold for any of the air pollutants could be established for asthma admissions Professor Lau believes there is an urgent need for health policy makers to develop more stringent air quality objectives that will take high risk groups – like the young, the old and those with chronic respiratory illness – into consideration. “If ambient levels of these pollutants were reduced by an average of fifty per cent it could have cut the number of hospital admissions during the study period by around 3,400,” he said.