With dengue fever growing in prevalence across Asia, Hannah Ball consults Dr Yau Wing Him of Quality HealthCare Medical Centre ? DB
A mosquito-borne tropical disease, dengue fever is thought to affect somewhere between 50 to 100 million people annually in over 100 endemic countries. It?s particularly prevalent in the Philippines and Thailand, and increasingly on the mainland. In neighbouring Guangdong, more than 40,000 people contracted the disease in 2014 alone, and six died from it.
The Centre of Health Protection in Hong Kong advises that comparatively few people contract dengue fever locally, but it?s worth noting that there were 31 confirmed cases in 2005, compared to 103 in 2013. Last year, three people are known to have picked up the disease locally, and 105 imported cases were confirmed.
?Increased travel to countries where dengue is endemic means that more people return carrying the dengue virus in their blood,? says Dr Yau Wing Him of Quality HealthCare Medical Centre ? Discovery Bay. ?Increasing cargo transport from these countries can also inadvertently import dengue-infected Aedes mosquitoes.?
Symptoms and treatments
Ten-year-old Cheung Sha resident, Lauren Price tested positive for dengue fever just two days into her holiday in Bali in October, 2014, and it?s therefore possible that she picked the disease up here in Hong Kong. Her symptoms included tiredness, headache and stomach ache, and a high fever (39.6?), which lasted for three days.
?She was lethargic and didn?t eat much,? says Lauren?s mum, Lindsey. ?She was red in colour and hot to the touch, and her hands and feet were cold and clammy. She became very weak and suddenly vomited with no warning and then collapsed on the bathroom floor, which is when we called the emergency doctor.?
?There are four different serotypes of dengue viruses (Den-1, -2, -3 and -4),? explains Dr Yau. ?They are not graded in terms of severity, but each can cause dengue fever, or the more severe and potentially fatal dengue haemorrhagic fever, which causes sufferers to bleed or haemorrhage and can lead to circulation collapse.
?In most cases, dengue fever acts as a severe flu-like illness, lasting between three to 10 days, with common symptoms including the sudden onset of high fever, severe headache (especially behind the eyes) and muscle and joint pain,? Dr Yau adds. ?Those who recover from one serotype of dengue fever have immunity from that particular serotype, but not the other three.?
Hospitalisation can be necessary for sufferers with dangerously low blood platelet or white blood cell counts, and those in extreme pain. But according to Dr Yau, most cases are treated symptomatically. In Lauren?s case, it was a matter of keeping her body hydrated, and waiting for her blood platelet count to return to normal.
While general measures to prevent mosquito bites (such as spray) will reduce your chances of getting infected, Dr Yau says the most important thing is to avoid stagnant water, where mosquitoes breed. ?Sanofi Pasteur is currently developing a vaccine, with early trials showing it prevents dengue fever in just over 50% of those vaccinated,? he adds.
Lindsey has created a Dengue Fever Support Facebook group to raise awareness about the disease. ?It is time to be aware of the virus,? she says, ?especially when travelling to other parts of Asia where dengue fever is at an all-time high.?
You can contact Dr Yau at Quality HealthCare Medical Centre ? Discovery Bay on 2987 5633.