Cheap cream can boost flu jabs for elderly, HKU study shows
HKU study shows that medication commonly used to treat genital warts can boost vaccines
Hong Kong scientists have discovered that a cheap and readily available cream used to treat a sexually transmitted disease can make flu vaccines more effective for the elderly.
Professor Yuen Kwok-yung, a microbiologist at the University of Hong Kong and one of the world's leading flu fighters, said doctors can apply imiquimod - a medicine for genital warts - to the skin of patients before giving them their shots.
Yuen said the medicine helps to boost antibody levels and stimulate the effects of the influenza vaccine, especially among elderly or chronically ill patients. He said they knew imiquimod stimulated the body's cells and launched the study to determine if it had wider medical use.
"It is an important advance in immunisation," he said. "Pretreatment with imiquimod significantly speeded, boosted, and prolonged the immunogenicity of flu vaccination - a strategy that should be pursued for older people.
"The drug is widely available and is as cheap as HK$20 [for each dose]. All doctors can actually start using it on old patients."
The team, led by Yuen, conducted tests on 90 patients and found that the 30 who had applied the cream gained much more protection against flu viruses. The treated patients had a significantly higher antibody level seven days after immunisation, and the effects of the vaccine can last for more than a year.
The findings were reported this week in the journal Clinical Infectious Diseases.
Yuen pointed out that the annual influenza vaccine only works for 70 per cent of patients, and the effects for those over 65 with several illnesses can last as little as six months. This means that high-risk groups who receive flu jabs once a year may not be protected during winter or summer flu peaks.
Yuen believes that application of the cream can solve this problem. But he said doctors should only use it on elderly and chronically ill patients.
"A normal healthy adult should gain enough protection from the flu vaccine and there is no need for them to use this method," he said.
Patients who applied the cream on their arms before receiving a jab developed no significant side effects except slight local swelling of the injection area.
Yuen and HKU's Ivan Hung Fan-ngai, who began the study three years ago, first demonstrated the effect in mice before carrying out a trial on humans in 2012.
Yuen was honoured as an Asian hero by Time magazine for his work during the outbreak of severe acute respiratory syndrome in 2003.