Letter to Hong Kong



Dear Sophronia,

The new semester has just started.  How are you getting along with the first term of your master studies?

 Over the past few weeks, there had been a lot of confirmed local cases suffering from dengue fever.  Comparing with the recorded cases between 2015 & last year, it is obvious that there is a surge of locally infected cases this summer.

Blood sample testing of these cases indicates that they are only positive for dengue virus serotype 1, that is, uncomplicated dengue fever, and, fortunately,  most of these patients are in stable conditions.

It is noted that an initial contact with dengue virus of any serotype will normally result in mild symptoms, such as fever and headache.  However, if exposure to subsequent infection is with another serotype of dengue virus, the patient could end up with a more severe condition, namely the Dengue Hemorrhagic Fever, which would experiencecoma, organ failure and even death.

To protect the public from the threat of dengue fever, it is necessary for the Government to be more vigilant in fighting against this mosquito-borne disease.

Although the Government has announced a temporary closure of the Lion Rock Park, and the conduction of thorough mosquito eradication and control measures in Cheung Chau, the showers and thunderstorms over the past weeks provide a favorable condition for massive mosquito breeding, and, worse still, stagnant water after the rain allows mosquitoes to thrive again.

With such adverse weather, the risk of spreading mosquito-borne diseases may be aggravated.  Therefore, the Government should continuously carry out intensive and timely anti-mosquito measures including fogging in the scrubby areas, applying insecticide and frequent trimming of grass to prevent mosquito proliferation.

The Aedes mosquito is believed to be the main vector that transmits the virus which causes dengue fever.  According to the World Health Organization, Aedes mosquitos have a short flight range with only around 100 m, and egg production sites are likely to be closed to where these mosquitos are found.  However, these eggs could sometimes also be transmitted via cargos, tyres, containers, and, even, clothing.

Hence, in the case of Hong Kong, residents and visitors of the Lion Rock Park or Cheung Chau may unnoticeably carry out mosquito eggs that have laid on their clothes and bags to the city center, and, as a result, scaled up the mode of spread in the community.

In view of the situation, it is suggested that apart from carrying out district-based anti-mosquito operations, the Government should also initiate a territory-wide exercise onprevention of mosquito bites and mosquito breeding to avoid further outbreak of the disease.

Moreover, it seems that some members of the public have overlooked the severity of dengue fever.  There has been news reporting that some people are still continuing their morning exercises around the Lion Rock Park.

As mentioned earlier, though some dengue infected people may not develop apparent symptoms, and some first contracts may only have mild symptoms like fever, subsequent infections with other serotypes of dengue virus are more likely to result in severe dengue cases which may end up with poor prognosis and grave recovery.

Thus, the Government should also take this opportunity to caution the individuals on the possible impacts and associated problems with this acute mosquito-borne infection.

They should be reminded to stay vigilant on taking precautionary measures of preventing mosquito bites, and to stay away from visiting those high risk areas unnecessarily.

As suggested by the Center for Health Protection, individuals are advised to wear light-colored and long-sleeved clothing and trousers, apply mosquito repellents containing DEET to exposed parts of the body, use mosquito nets or screens when the room is not air-conditioned, avoid visiting scrubby area and install screens on windows and doors.

Community efforts are also very important.  It is hoped that the Government should take continuous actions to remind the public to heighten vigilance and keep up effective prevention and control measures against mosquitoes, as well as to take personal protective measures to reduce the risk of contracting mosquito-borne diseases through mosquito bites.

Meanwhile, the Hospital Authority should also raise its alertness and readiness for the contingency response measures in managing the possible outbreak of dengue fever in Hong Kong, and in particular, the public hospitals should be prepared to manage an overwhelming influx of severe dengue fever cases due to subsequent infections.

Recently, it is reported that an error had been made in a laboratory test on the serotype of dengue virus which could indeed have detrimental impact on the management of dengue fever.  Assuming that such incident may be resulted from a sudden surge of workload, the Government, in particular, the Center for Health Protection, should rectify the situation and to sustain the effectiveness of the testing laboratory by allocating appropriate resources in an timely manner.

Interesting, it is also noted that the ovitrap index for Aedes mosquitoes over the past months is of record high, yet, the Food and Environmental Hygiene Department is still reluctant to carry out a territory-wide anti-mosquito operations.

The new school term has just started after the summer recess.  Schools and educational institutions are crowded with students, and, possibly, mosquitoes as well, so the risk of transmitting dengue fever may come to concern.

To prevent the transmission of dengue fever, schools, students and parents should be advised to follow appropriate personal protective measures against mosquitoes bites and keep the school areas and the environment clean against mosquito breeding.  Removal of stagnant water is of prime importance to the prevention of mosquito breeding and proliferation.  It is therefore suggested that school should appoint a designated staff for mosquito prevention and control.  Schools have to be inspected at least once a week to remove stagnant water.  As Aedes mosquitos may lay eggs in small pools of stagnant water, refuse such as soft drink cans and lunch boxes should be properly disposed of in covered litter containers.  Moreover, the school can also hold talks and disseminate booklets to students and parents, teaching them the proper way to prevent mosquito bites and breeding.  Both the Government and schools should remain vigilant against the transmission of dengue fever.

In the long-run, the Government should commit to carry an ongoing territory-wide anti-mosquito policy to control mosquito proliferation all year round so as to prevent the Dengue to become an endemic illness.

All the very best for your further studies.


Uncle Joe


更新日期: 2018-9-14