ANYONE walking into a hospital in an urban area these days is likely to be swarmed by dengue or suspected dengue patients.
Last year, an astronomical 108,698 dengue cases with 215 deaths were reported to the Health Ministry, more than double the figure in 2013. That’s close to 300 cases a day and four deaths per week.
Dengue infection has become one of the leading causes of hospital admission among adults and also a major cause of illness and deaths, according to “A Review of Dengue Research” published in the Medical Journal of Malaysia, Vol 69 Supplement A, August 2014.
The numbers are not getting any better this year. As of Feb 7, a total of 15,039 dengue cases have been reported this year with 44 deaths. That’s close to 400 cases a day and at least one death every day. During the same period last year, there were 9,453 cases with 17 deaths.
In fact, Health director-general Datuk Seri Dr Noor Hisham Abdullah said that there is a substantially higher percentage of patients who show symptoms of severe dengue.
“These could mean dengue with plasma leaking from the blood vessels, bleeding and dengue with severe involvement of organs such as the liver, brain, heart and kidneys,” he said.
There has also been an increase in dengue patients with underlying medical conditions who come in with uncommon symptoms and suffer more throughout the course of the disease, he said.
He said the severity of a particular infection was not solely dependent on the dengue strain’s virulence, but also on the interplay between the micro-organism and the patient’s immune system.
“That is why patients tend to develop life-threatening diseases only after the virus is cleared from the blood,” he said.
Dr Noor Hisham said recurrent dengue infections, possibly within a short interval, make a patient more prone to a severe form of the infection.
“It is as yet uncertain whether the increase in severe dengue cases is solely due to this particular reason,” he said.
Due to these concerns, the Ministry has told doctors to start looking for other dengue symptoms, rather than just fever and rashes, before they are considered for admission.
The symptoms are lethargy, vomiting, diarrhoea and abdominal pains.
Patient profile
Dr Noor Hisham said that among the 215 dengue patients who died last year, the average duration from onset of fever to hospital admission was four days, and the average duration of hospital stay from admission to death was another four days.
He said those who died mostly came from districts with a high number of dengue cases such as Petaling (9.6%), Hulu Langat (8.5%), Gombak (7.4%), Johor Baru (7.4%), Kinta (7.4%), Kota Baru (5.9%) and Klang (4.8%).
Of the number, 55% of the dengue deaths involved Malays, 22.3% Chinese, 13% Indians, 5.1% foreigners and 3.7% others.
More than half – 58.6% – were aged between 15 and 50, while 30.7% were aged above 50 years and 10.7% were below 14.
Of the cases, 53% were females and 47% males.
About one in every four (23%) patients who died of dengue had other illnesses such as diabetes, hypertension, heart disease, renal failure and risk factors such as obesity, pregnancy and old age.
Dr Noor Hisham said the Ministry took all dengue deaths seriously.
“Every death is discussed at multiple levels and every management decision is scrutinised, including the diagnostic tests done and the reporting of the case to the public health authorities,” he said.
Asked if dengue serotype and other viral cross-infections could happen in the hospital ward leading to patients’ severe conditions or deaths, he said it was theoretically possible but that there had been no evidence to suggest that this was happening in Malaysia.
“If there were cross-infections between patients in hospitals or among people living near hospitals, then the majority of people with dengue would be from these groups but so far, that has not been the case,” he said.
Most hospitals where dengue is common have taken steps to create specialised wards to cater to the increasing load of patients as well as to streamline human resources, investigations and monitoring of these patients, he said.
“The ministry’s hospital authorities regularly patrol their grounds to ensure they are free of mosquitoes,” he added.
World Health Organisation Representative to Malaysia, Brunei and Singapore, Dr Graham Harrison, said Malaysia already had a good level of expertise in the clinical management of dengue and had taken many steps to ensure that there is effective identification and treatment of people with dengue.
However, he said one challenge was people’s own understanding of the need to get early medical assessment, which could lead to more severe complications that can be harder to treat.
“Unfortunately, the clinical presentation of dengue may mimic symptoms of upper respiratory tract infection, and someone who has these symptoms may not identify the need to see a healthcare provider quickly or may not be concerned with completing the follow-up steps as recommended by their doctors,” he said.
Rethinking strategies
WHO Collaborating Centre for Arbovirus Reference and Research director Prof Dr Sazaly Abu Bakar said that Malaysians have been doing the same thing for the last 30 years and it is time to adopt new approaches.
With new concerns that more people are suffering from more severe dengue and dying from it, he said, attention should be directed to preventing deaths.
He also expressed concern over transmission of the virus when Aedes mosquitoes bite patients who are asymptomatic or have mild symptoms.
“It may be mild in this person but if the virus load is high, the person could become the source of infection in others which may not necessarily be mild,” he said.
He said the ministry has all the data and it is a matter of what they do with the data to bring down the numbers.
Dr Sazaly said people could continue getting rid of dengue breeding spots but it would still not make a difference as long as infected humans do not prevent themselves from being bitten by mosquitoes.
In a letter to The Star, a retired public health specialist had pointed out that Aedes mosquitoes by themselves do not transmit dengue but get the virus from humans and transmit it to others.
He said that the public health advisory should be given to every person diagnosed or suspected of having dengue to break the cycle of infection by protecting oneself from being bitten by mosquitoes with protective clothing and limiting outdoor mobility, as well as destroying adult mosquitoes in and around the house with insecticide sprays.
Patients or family members should check in and around the house to find and destroy Aedes or potential Aedes breeding places, while neighbours must be informed as mosquitoes have a flight range of at least 200m, he said.
Asymptomatic patients pose challenge in controlling infection
Dr Noor Hisham (pic) also said that as in most other infections, one in four patients carry the dengue virus without exhibiting any symptoms or any serious symptoms.
“This is one of the main reasons why it can be very difficult for public health authorities to control the disease despite dengue being a strict notifiable disease,” he said.
Asked if the ministry needed to change its approaches to tackle the rising number of cases, Dr Noor Hisham said the principal approach in dengue control worldwide is breeding source reduction.
Fogging and other methods of spraying insecticide are temporary measures. Dengue control is highly dependent on the destruction of Aedes breeding, which is within the control of the public, he said.
However, as long as Malaysians continue their bad habits of littering, illegal dumping of garbage, apathy on breeding within their own homes, not bothering about community work and poor environmental cleanliness, and construction sites continue to ignore guidelines, they are fighting a losing battle.
“Yes, we need to change Malaysian attitudes towards cleanliness,” he said.
“Our researchers must also think out of the box to find more tools to fight Aedes and the dengue virus,” he added.
Dr Harrison said that dengue was a very difficult problem to eliminate.
“Until an effective and affordable vaccine is readily available, dengue is likely to persist as a an ongoing health problem, with some exacerbations in the numbers of cases from time to time.”
It is important for the community to understand that they must be engaged with dengue control because officers from the local government and health departments can only do so much, he said.
“Individuals must take responsibility for regularly checking around their homes and workplaces to ensure that there are no potential mosquito breeding places, and if there are ways to take action – either to drain the water away or use appropriate chemicals or biological methods to stop further mosquito breeding,” he said.
This is not a one-off activity but requires regular attention to remove rubbish and inspect possible places where water may be collecting and to take further action, he said.
While the relevant authorities carry out their checks and impose penalties, perhaps it is time for all resident associations to be galvanised into getting residents to take turns and work together to do clean-ups in their own area on a regular basis
