Cambodia - Dengue Cases on the Rise

Dengue cases, which can be highly lethal to children, rose phenomenally in the first five months this year and more than doubled compared with the same period last year.

The Ministry of Health, in a statement released yesterday said that from January to May this year there were 1,915 cases and four deaths. Last year, the ministry said, there were 567 cases with one death.

The statement said dengue cases normally peaked after a cycle lasting three to five years and this year more cases are expected due to the abnormally high atmospheric temperatures associated with intense El Nino events.

Health Minister Dr. Mam Bunheng urged Cambodians to exercise strict caution during the rainy season to prevent themselves from being bitten by the Aedes mosquito that carries the dengue virus.

In the statement, Dr. Bunheng said parents should ensure the surroundings of their houses were kept clean and all mosquito breeding areas destroyed to eliminate the Aedes larva. This is to prevent children from getting dengue, he said in the statement.

Children are susceptible to dengue and often succumb to dengue hemorrhagic fever if there is a delay in seeking help from health centers or hospitals. There is no treatment for dengue and generally the fever resolves on its own with the help of intravenous fluids.

“Please rush your child to the nearest health center if he or she has high fever because dengue can kill,” said the minister.

 Dr. Bunheang said the larvacide Abate was the most effective in eliminating the Aedes mosquito in its breeding sites, with the Abate pellets put in water jars and containers – the mosquito’s favorite breeding places.

Secretary of State at the Ministry of Health Dr. Eng Huot issued a directive letter to all provincial and city health department directors to take action in preventing dengue outbreaks.

He said in the letter that “there was a significant increase of dengue cases in Kampong Thom, Siem Reap, Kandal, Kampong Cham, Kampong Chhnang, Banteay Meanchey, Preah Vihear and Phnom Penh as well.”

Dr. Hout ordered all provinces to put Abate in water jars and all water containers.

The director of the National Center for Parasitology, Entomology and Malaria Control, Dr. Huy Rekol, could not be reached for comment yesterday.

Director of Kampong Cham Provincial Health Department Kim Sourphirun told Khmer Times yesterday that the department gave the larvacide Abate to all the province’s nine districts. Each district, he said, received one ton of Abate for killing the dengue mosquito larva.

Mr. Sourphirun also said supplies of serum had also been prepared for intravenous use in emergency cases of dengue hemorrhagic fever.

Mom Kunthear

Khmer Times

Cambodia - Cambodia waiting for WHO dengue vaccine approval

Although the number of dengue fever cases in Cambodia nearly tripled during the first 17 weeks of 2016 compared to the same period last year, a health official said a vaccine for the mosquito-borne virus still needs to be vetted by the WHO before local licensing and introduction could be considered.

From January to April, the Kingdom saw 1,510 confirmed dengue cases and three deaths, compared to 550 infections and one death at the same point in 2015, said Rithea Leang, the national dengue control program manager at the Ministry of Health.

In spite of several recent meetings in which the dengue vaccine has come up, he added, the ministry is focusing on the Japanese Encephalitis vaccine for the time being.

“WHO is awaiting a submission of an application from the manufacturer for prequalifications of this vaccine,” he said.

The dengue vaccine, dengvaxia, was first licensed in Mexico in December 2015 for use in individuals aged 9 to 45 years old living in endemic areas. It was developed by French drug maker Sanofi and approved based on two large trials that showed it protected two-thirds of its participants against all four of the virus’ serotypes.

A group of WHO experts met last month to review the vaccine, and recommended that countries consider introduction of the vaccine only in geographic settings with high incidence rates, Leang said.

WHO in July will publish a report specifying its position on the vaccine and outlining its recommendations. WHO Cambodia officials could not be reached for comment yesterday.

The number of dengue cases on a yearly basis in the Kingdom ranges from 10,000 to 25,000, Leang said.

“We cannot predict the impact specifically for Cambodia until it can be introduced to the community,” he added.

Rob Kelly, a spokesman for the pro-vaccine non-profit GAVI, which has committed millions to support immunisation in Cambodia, said GAVI only funds vaccines that have received the green light from WHO.

“As things stand, the vaccine has received regulatory approval, but has not yet received prequalification or a WHO recommendation for use,” he said.

However, he added, GAVI has a process it uses to help its board decide whether to make funding available for new vaccines – with the next one due in 2018 – and dengue will be considered as part of that process, he added.

Yesenia Amaro

phnompenhpost

Singapore - Dengue cases in Singapore rise

The number of new dengue cases in Singapore rose to 244 with 15 new cases recorded last week, according to latest figures published by the National Environment Agency’s (NEA) on Wednesday.

Another 44 cases were reported between May 1 and 3, Channel News Asia reported.

A total of 7,370 dengue cases have been reported in Singapore since the start of the year. Four people have died of the disease.

The health ministry and NEA have warned that the number of dengue cases in Singapore may exceed 30,000 this year, higher than the record of 22,170 reported in 2013.

This is due to factors such as warmer conditions brought about by the El Nino weather phenomenon, faster breeding and maturation cycles of the Aedes mosquito population and a change in the main circulating dengue virus.

There are now 61 active dengue clusters in Singapore, including 12 classified as high-risk.

ianslive

Philippines - Philippines dengue vaccine update: 200,000 kids vaccinated, 362 adverse events, details on child death

In an update on the first of its kind immunization program with the newly approved dengue vaccine, Dengvaxia, Philippines health officials (DOH) provided the following update Monday.

The Dengue School-Based Immunization program that commenced on Apr. 4 continues on and at the three week mark, a total of 204, 397 (73%) pupils were vaccinated out of 279,393 pupils with parents’ consent.

As of April 24, 2016 a total of 362 cases of Adverse Event Following Immunization (AEFI) from the three regions where the Dengue School Based Immunization Program were received. The top five common reactions were fever, headache, dizziness, vomiting, and rash. The DOH established a strict monitoring and surveillance system for adverse events and side effects following immunization.

There has been a lot of coverage on the fatality of an 11-year-old boy who was vaccinated on Mar. 31.  The DOH offered the following details and explanation of the case:

The patient is claimed to have been diagnosed to have congenital heart disease during his childhood. No maintenance medication was taken since his transfer to his current guardians.  During immunization of dengue vaccine, the patient was screened and assessed by the RHU physician at the school. When asked the guardian (uncle) denied history of fever, illness, and maintenance medication during assessment.

On April 3, 2016 patient developed diarrhea and fever, he was seen and examined the next day at the Bagac Community Medicare Hospital and was diagnosed to have amoebiasis. Patient was sent home with medications. On April 9, the patient was seen and admitted at the Isaac Catalina Medical Center after experiencing difficulty of breathing, fever, and cough. He was initially diagnosed with pneumonia, severe; congenital heart disease in Congestive Heart Failure, and electrolyte imbalance. April 10, the patient was referred and transferred to Bataan General Hospital. April 11, patient had a cardiac arrest and was eventually pronounced dead. The immediate cause of death was pulmonary edema with the following underlying causes: congenital heart disease, Acute Gastroenteritis with moderate dehydration.

The case was presented to the National Adverse Event Following Immunization Committee (NAEFIC) last April 21, 2016 to assess the findings. Their conclusion is consistent with the hospital findings. The dengue vaccination is coincidental. According to NAEFIC, congenital heart disease is not an exclusion criterion for vaccination.

The Philippines reported more than 200,000 dengue cases last year and nearly 600 deaths. As of April 9, 2016, a total of 33, 658 suspected dengue cases were reported nationwide. The Philippines has the highest incidence of dengue and ranks number 1 in the Western Pacific Region from 2013 to 2015.

outbreaknewstoday

Malaysia - Malaysia Registers 25,000 Cases of Dengue Fever in Three Months

Kuala Lumpur, Malaysia, Apr 25 (Prensa Latina) Malaysia has registered nationally almost 25,000 cases of dengue fever, the Malaysian Public Health Vice Minister, Hilmi Yahaya has confirmed

Hilmi Yahaya stated that from January until April 24th, 42,683 cases have been reported, a rise of almost 5,000 in comparison with the same quarter last year.

Ninety-four people have died in the same period, which is a reduction on the 120 victims who succumbed to the disease in same quarter in 2015.

According to official data, during January and February this year, the authorities inspected almost 1,000 areas, imposed 3,260 fines and took 353 cases to court.

Yahaya thanked other ministries and governmental agencies for their help in the national operation, which started on April 11th, against the Aedes Aefypti mosquito - the transmitter of the disease.

Analysts have said that the country's initiatives against dengue fever are ineffective, despite being regional pioneers in research on the transmitting agent.

In 2011, Malaysia sterilized 6,000 male mosquitoes and released them to mate with females with the aim of reducing the mosquito population.

The experiment was the first of its type in Asia and although the population of mosquitoes has been reduced, this has not led to a drastic reduction in the incidence of dengue fever.

According to the World Health Organization, in 2015, the hospitals in Malaysia treated 111,000 suspects dengue fever cases, an increase of 16 percent in comparison to 2014.

The WHO also reports that in 2015, 390 million cases of dengue in at least 128 countries were reported.

Dengue fever is transmitted by the bite of the female of the Aedes Aegypti that nests in stagnated waters.

The symptoms are fever, headache, and pains in the joints and muscles.

sgl/Ym/tac/to/ymn

plenglish

Malaysia - Malaysia focuses on dengue at World Health Assembly

KUALA LUMPUR: Malaysia will take the lead in bringing dengue fever concerns to the world's attention at the coming World Health Assembly, said Datuk Seri Dr S. Subramaniam.

The Health Minister said that Malaysia would host a side event on dengue at the meeting in Geneva, Switzerland, at the end of May.

"Dengue has never been given the ‘centre stage’.

"Through our initiative, we have taken dengue to the centre stage of the World Health Assembly itself and for the first time, we will be hosting a side event there," he said in his speech at the Asia Dengue Conference on Saturday.

Dr Subramaniam said that various experts would be invited to share information on dengue during the event.

He said that dengue had spread to many parts of the world and yet it had not received much attention in international meetings.

It is a serious issue in Malaysia and affected those in the productive age, he said.

As many as 42,271 dengue cases were reported from January to April 22, a 10.8% increase compared with 38,139 cases for the same period last year.

However, there were 94 deaths for the same period this year compared with 119 during the same period last year, a decrease of 21%.

He said that in the last two years, the pattern of dengue cases had changed and had affected more of the heart, brain and kidneys.

Meanwhile, deputy health director-general Datuk Dr Lokman Hakim Sulaiman said that 60,682 premises had been inspected since the nationwide enforcement operations on dengue began on April 11.

Out of the number, 351 were fined, with the total fine collected amounted to RM175,500.

Dr Lokman said that 105 construction sites were also inspected and four of the sites were ordered to close until they were cleaned up while another seven cases were brought to court.

"We have found less premises with mosquito breeding sites. Perhaps people have started to check their homes after hearing of the enforcement operations," he said.

He advised the public to check on the ant trap in the floor, water containers that are used for washing dishes, roof gutters, air-condition compressor and homes that people themselves had left empty.

thestar

Singapore - World's first dengue vaccine out next year

The world's first dengue vaccine will hit the shelves next year, following the completion of trials that found it 56 per cent effective.

Produced by French pharmaceutical giant Sanofi, it offers varying degrees of protection against each of the four types of dengue virus. For Den-3 and Den-4, it offers 75 per cent protection; for Den-1, it is 50 per cent; and for Den-2, it is just 35 per cent.

Unfortunately for Singapore, the latter two types are the ones most commonly found here. "It is promising, but not perfect," said infectious diseases expert Annelies Wilder-Smith of the Lee Kong Chian School of Medicine.

Dengue cases have continued to rise over the years and there is currently nothing else to fight the mosquito-borne disease, said Professor Wilder-Smith, who is also an infectious diseases specialist at Tan Tock Seng Hospital.

A record 891 cases were reported in Singapore last week and since Sunday, another 630 people have fallen ill. So far this year, 10,184 people have become sick and one has died.

Of the 110 active dengue clusters, the biggest is in Choa Chu Kang with 160 people infected in just the past fortnight.

The results of the clinical trial of Sanofi's dengue vaccine on more than 10,000 children in Indonesia, Malaysia, the Philippines, Thailand and Vietnam were published in medical journal The Lancet yesterday. Children aged two to 14 were given three jabs over one year and were followed up for another year.

Prof Wilder-Smith was not sure how relevant the study is to Singapore, as most dengue victims here are adults.

But it might actually work better in grown-ups because the vaccine was found to have a greater effect on children who had been infected previously, she said.

In Singapore, about 45 per cent of adults have had a dengue infection by the age of 45, though many might not be aware of it as their symptoms could have been mild. In the trials, older children received better protection from the vaccine.

Prof Wilder-Smith said in a commentary in the same edition of The Lancet: "This vaccine boosts and broadens pre-existing immunity rather than raising protective immunity. Perhaps the most interesting finding of this trial was the efficacy after at least one dose was almost as high as that after three doses."

A plus point for the vaccine, she said, is that it reduced the serious form of dengue by up to 80 per cent. But whether it is cost-effective to vaccinate the population will depend on the pricing, which has yet to be announced.

The health ministry said it will study the report, adding: "One of the challenges in dengue vaccine development has been ensuring that there is good protection against all four serotypes."

A second clinical trial in Latin America involving more than 20,000 nine to 16-year-olds ends later this year.

Salma Khalik

The Straits Times

Malaysia - Huge spike in dengue cases and deaths in Malaysia

For those who thought that the rise in the number of dengue cases was bad, here’s the real bad news – there has been a 248 per cent spike in the number of cases this year, and a 228 per cent increase in the number of deaths.

The total number of reported dengue cases throughout the country this year rose to 42,229 cases compared to 12,143 for the same period last year,” said health minister Dr S Subramaniam.

As at June 21, 82 people have died of dengue nationwide – a 228 per cent increase compared to the 25 recorded over the same period last year.

On a weekly basis, Dr Subraman­iam said 2,021 cases were recorded from June 15 to June 21, a 12.5 per cent increase compared to the 1,797 cases reported the previous week.

Four deaths were reported for the week beginning June 15, including that of a five-year-old boy in Selangor.

“All cases were given treatment before they died due to dengue-related complications,” he added.

Dr Subramaniam had previously said the number of cases were higher this year due to the shift in the dominant dengue virus serotype that is circulating here.

Four serotypes are always in circulation (DEN-1, DEN-2, DEN-3, and DEN-4), but the dominant serotype can change from time to time. DEN-2 has been found to be the prevalent serotype here since the middle of last year.

With the current fasting month under way, Dr Subramaniam said Ramadan bazaar areas should be kept clean to prevent them from turning into mosquito breeding grounds.

“Bazaar operators and visitors should ensure that cleanliness is maintained and rubbish is not thrown everywhere.

“That could lead to the water stagnating and forming breeding grounds for Aedes mosquitoes.

“Mosque areas should also be free of mosquitoes,” he said, urging all parties to do their part to prevent dengue.

He encouraged the public to use repellents or to cover up to minimise chances of being bitten by the Aedes, which typically feeds in the mornings or dusk.

The Star

Singapore - Keeping the dengue virus unmasked

Mosquitoes spread four different strains of dengue virus, each of which causes dengue fever. For a vaccine to be effective, it needs to prevent infection by all four strains.

A method that stops the dengue virus from resembling a host’s RNA could yield an effective and affordable vaccine

Cases of dengue fever — a potentially life-threatening disease spread by the Aedesmosquito — are increasing worldwide, thanks to expanding mosquito habitats. According to the World Health Organization, the dengue virus infects 50 to 100 million people annually, with Southeast Asia and South America most affected.

An effective and affordable vaccine has eluded scientists, largely because the dengue virus can be one of four types. Each serotype, or any combination of the types, can prevail in a single location. Thus, an effective inoculation needs to confer protection against all of the serotypes.

Katja Fink and co-workers at the A*STAR Singapore Immunology Network, together with scientists across Singapore, China and the United States, have developed a novel strategy for producing a live dengue fever vaccine¹. The vaccine currently protects against two of the serotypes, and the team is working to expand this to all four strains.

“We used a mutated form of the dengue virus to create the vaccine,” says Fink. “The mutated virus replicates slowly in the body but does no harm, creating an immune memory response, which is triggered if the host encounters the wild-type virus.”

Usually, RNA molecules in the dengue virus are modified by an enzyme called MTase that adds a methyl group to the viral RNA. This methylation makes the viral RNA resemble the host cell’s RNA and consequently, the body’s immune system does not attack it. Fink and co-workers created mutations in MTase so that the RNA remained unmodified by methylation. The mutations led to a form of the dengue virus that cannot spread quickly yet triggers an effective immune response.

“Our virus is the first live dengue vaccine that contains defined mutations to block a viral enzyme,” explains Fink. “These mutations could be equally introduced to all four serotypes, meaning that no serotype would have an advantage over the others — a situation that otherwise creates an imbalanced immunity.”

The new vaccine gave full protection against wild-type virus infection when tested in mice and monkeys. The researchers found that the mutations remained stable over time and did not revert to the wild type, a potential complication in vaccine development. Furthermore, mosquitoes feeding on blood containing the mutant dengue virus did not become infected.

Live vaccines are relatively cheap and easy to produce. “The enzyme mutation can also be introduced into new strains if dengue virus evolves over time,” says Fink. “Our next challenge is to see whether we can achieve full protection against all four serotypes.”

Reference

1. Züst, R., Dong, H., Li, X.-F., Chang, D. C., Zhang, B. et al. Rational design of a live attenuated dengue vaccine: 2’-O-methyltransferase mutants are highly attenuated and immunogenic in mice and macaques. PLoS Pathogens 9, e1003521 (2013). | article

http://www.research.a-star.edu.sg

Malaysia - Dengue Deaths Up in Malaysia

KUALA LUMPUR, Malaysia—Deaths from dengue in Malaysia shot up this year, doubling that of 2012, as the tropical country battles with a raging mosquito-borne virus that claims hundreds of lives annually in Southeast Asia.

Four patients — three women and one man — died in the week ending Dec. 21, leaving 88 dead in Malaysia in the first 51 weeks of this year. In 2012, 35 people died in Malaysia of dengue, data from the Ministry of Health show.

Malaysia suffered the worst dengue bout on record in 2010, when 134 people died and 46,171 cases were reported. In 2011, 36 people died in Malaysia, with 19,884 people infected.

As of Dec. 21, dengue cases totaled 41,226 , nearly doubling from 21,444 cases in same period in 2012.

“As long as infection and outbreak of dengue fever continues, the risk of death remains,” said Lokman Hakim, deputy director general at Malaysia’s Ministry of Health.

The virus, which is transmitted by the Aedes aegypti mosquito, causes severe fever, headaches, rashes and muscle and joint pain. Severe forms can cause hemorrhagic fever. No vaccine is currently available, and treatment is largely limited to intravenous rehydration.

Selangor state, which borders the capital city of Kuala Lumpur, has been hit the hardest, reporting 24 deaths, the Ministry said. The southern state of Johor that borders Singapore, has recorded 21 fatalities.

Selangor is home to 88 of the 89 dengue “hotspots,” or areas that have witnessed a jump in outbreaks, with Negeri Sembilan accounting for the other.

To try to reduce dengue, Health Ministry officials routinely search thousands of premises around the country to identify potential breeding grounds. People who have pools of stagnant water containing Aedes’s larvae face fines of a minimum of 500 ringgit (US$152). Those who fail to pay could be fined as much as 10,000 ringgit, face up to two years in jail, or both for a first offense. Repeat offenders can be fined five times as much or face five years imprisonment.

“Of late, the searches have become very frequent,” said Shakeel Mustafa, a manager at a restaurant in a suburb bordering Kuala Lumpur. “We ensure that the alley behind our kitchen is cleaned every day.”

The ministry has also urged citizens to drain out stagnant water from around their houses and pressed non-profit organizations to bolster efforts to educate the public about hygiene.

Government health workers frequently conduct checks at construction sites, where tiny puddles serve as breeding grounds for the urban pests, and fumigate schools and other public places.

Abhrajit Gangopadhyay

http://blogs.wsj.com

Singapore - Evolution of dengue epidemic "at a critical juncture"

Environment and Water Resources Minister Dr Vivian Balakrishnan said Singapore has "reached a critical juncture" in the evolution of the dengue epidemic.

820 cases were reported last week, bringing the total number to 9,421. That is the highest ever in Singapore's history, surpassing even the previous peak during the 2005 epidemic.

The minister said it is going to get worse before it gets any better.

Apart from the rising numbers, there is evidence that dengue clusters are spreading across Singapore from the east, west to the northern regions.

There are four contributing factors to the current epidemic. Firstly, the Aedes mosquito is now predominant across the island. Secondly, the currently circulating dengue virus - Dengue Serotype 1 - has higher epidemic potential. Thirdly, the low immunity amongst the population makes people more vulnerable. Lastly, the hot and wet weather accelerates the life cycle of the Aedes mosquito and increases the likelihood of stagnant water accumulating.

Dr Balakrishnan said: "Our numbers are still rising and we are going into a peak dengue season so we cannot afford to lose control at this stage."

The National Environment Agency (NEA) will step up surveillance and inspection.

It will recruit another 300 officers over the next two months so that all premises in dengue clusters can be checked within a week.

Officers will be equipped with a new aerosol spray and it will be applied to dark corners of homes. The spray is said to last in the air longer and is more deadly to mosquitoes.

1.2 million insect repellents will also be distributed for free to households in dengue clusters.

Homes remain the top culprit for breeding spots.

Mr Balakrishnan said: "Infectious diseases are a test of special cohesion as a society and we need everyone to understand that our own health depends on the health of our neighbours and we need to exercise personal and collective responsibility for each other."

The Health Ministry has sent circulars to hospitals reminding them to be on heightened alert and give priority to returning A & E patients.

It has also released an additional 160 beds since March 2013, of which only 10 per cent are in use. By the end of the year, there will be another 90 beds added.

Dr Amy Khor, Minister of State for Health, said: “We have been working with every hospital, right down to the restructured hospitals to see where the added capacity can come from. And as the minister has said, the total absolute number of additional beds is there to cater to any surge in demand for beds due to dengue cases."

So far, only about 1.8 per cent of beds in public hospitals are occupied by dengue patients. Less than 30 per cent of dengue cases are admitted to hospital.

On the management of suspected dengue patients, authorities stressed that proper procedures are in place.

They added that most patients do recover from the disease.

So far, there have been two dengue-related deaths here this year.

The victims died after being discharged from A & E and re-admitted to hospital due to worsening conditions.

This has led some to raise concerns over the way suspected dengue cases are managed.

"Our doctors are working very hard on the ground... We can all sit down here and pontificate but there is no substitute for clinical judgement and one-on-one interaction for doctors. Our duty at the ministry level and administrative level is to make sure all the resources that are needed are available, so that whether you need beds, whether you need drugs, whether you need drips, whether you need any diagnostic tools, all those things are available, so that doctors can do what they do best," said Dr Balakrishnan. 

- CNA/xq/ir

Singapore - Dengue fever surges in Singapore 9,000 sickened

Singapore is telling doctors to be more vigilant against dengue fever as the mosquito-borne disease surges this year. The Southeast Asian city-state has had more than 9,000 cases and two deaths since January.

The illnesses counted so far in 2013 are already twice the total for all of last year. Singapore's health ministry said in a statement late yesterday that it has alerted clinics in neighborhoods where dengue cases have spiked and has advised all medical practitioners about the early diagnosis and close monitoring of patients.

Dengue fever, spread by the Aedes aegypti mosquito, is common in Asia and Latin America. Symptoms include high fever, joint pains and nausea, but in severe cases, it can lead to internal bleeding, liver enlargement, circulatory shutdown and death. Part of the reason for this year's increase is that the dengue virus seems to be showing more strength and resistance, said Asok Kurup, a doctor at Mount Elizabeth Hospital's infectious diseases care center, who has treated dozens of dengue cases this year.

Officials have urged Singaporeans to take precautions and clear stagnant water where mosquitoes breed, but some residents say the main responsibility lies with the health care system. "With so many cases occurring, shouldn't the vigilance fall on our doctors instead?" said homemaker Audrey Quek, whose teenage son had dengue two years ago. She said doctor initially mistook his fever and joint pains for flu symptoms, but he survived.

Authorities say they're taking other measures such as increasing insecticide fumigation and sending officers to inspect locations where mosquitoes might breed. Public awareness campaigns are also being planned, including an online reality show focusing on environmental officers on anti-dengue patrols.

Singapore imposes tough penalties on residents whose homes are found to be mosquito breeding areas. Offenders can be fined and jailed three months. Singapore's worst dengue outbreak in recent years was in 2005, when nearly 14,000 cases and 25 deaths were reported.

http://www.indianexpress.com

Malaysia - Dengue fever claims second victim

A SECOND person has died after being infected by the dengue virus in the current epidemic, which has affected more than 9,200 people here so far.

The 60-year-old man was admitted on his second visit to Tan Tock Seng Hospital’s (TTSH) emergency department.

A joint statement from the Ministry of Health and the National Environment Agency (NEA) said he had gone to the hospital last Wednesday “with fever, shortness of breath, vomiting and a rash on his left leg”.

The man, who lived in Ang Mo Kio Avenue 3, was diagnosed with skin inflammation of the left leg. He was given antibiotics and told to go to a polyclinic for a blood test at a later date.

But he returned to TTSH late last Friday night when his leg got so weak that he could hardly stand on it.

He was still having fever and had no appetite.

He was sent to a general ward the next day and diagnosed with dengue. Within hours, his condition worsened, and he was transferred to the intensive care unit.

He died of dengue shock syndrome yesterday morning.

Last month, Mr Ang Yong Han, 20, became the first casualty in this year’s dengue epidemic, expected to be the biggest Singapore has ever experienced.

He had gone to TTSH’s emergency department, but was given some Panadol and told to see a doctor three days later if he still felt sick. But he was feeling so ill that he returned to TTSH three days later and was warded. He died two days after that.

A TTSH spokesman said the latest victim had “multi-organ failure and complications associated with abnormal heart rhythm”. At the time of admission, he also had blood poisoning and suffered from diabetes and high blood pressure.

During the 2005 epidemic – when 14,000 people were infected and 25 died – half the dengue sufferers were warded. In the current one, about one in four is being warded. Hospitals are being more stringent in who they admit, largely because experts feel most do not need such care, and possibly due to the bed crunch at public hospitals.

TTSH, for example, has occupancy rates of over 90%.

Health Minister Gan Kim Yong has said that should the need arise, hospitals will postpone non-urgent surgery to find beds for dengue patients.

Dr Lam Pin Min, chairman of the Government Parliamentary Committee for Health, said: “It is imperative that all health-care givers stay vigilant and take all febrile cases seriously.

“Early cases may be deceptive and passed off as a viral fever or influenza. The full-blown symptoms and signs may not appear till later stages.”

His advice is to return to hospital should their fever persist.

Although there is no existing dengue cluster near the dead man’s home, NEA said it is stepping up its control of mosquitoes in that area.

The Straits Times / Asia News Network

Singapore - Immunology: Bracing for a viral counterattack

Antibodies (green) isolated from patients with a secondary dengue infection can effectively label cultured infected cells, demonstrating their strong affinity for the viral particle.

Insights obtained by profiling the immune response to repeat viral infections could assist vaccine design efforts

Patients who successfully beat infection with dengue virus remain vulnerable to reinfection by other dengue variants, and these secondary infections tend to be more severe. The antibodies arising from the immune system’s first encounter with the virus can play a complicated role in how these secondary infections unfold.

“Antibodies made during dengue infection can be either protective or disease enhancing,” explains Katja Fink of the A*STAR Singapore Immunology Network. Fink and her team wanted to determine whether the antibodies produced very early after infection promote defense or vulnerability. To do this, her team isolated plasmablasts — immature precursors of antibody-secreting plasma cells — from two patients newly diagnosed with secondary infection1. After conducting assays to determine the extent to which these cells were targeting the various subtypes of dengue virus, the researchers learned that most patient plasmablasts were specifically generating antiviral antibodies (see image).

The secret of the immune system’s success is its diversity, but when the body finds a threat that resembles something it has previously encountered, it specifically stimulates proliferation of cells that secrete antibodies appropriate to that threat. Fink and co-workers characterized the extent to which antibodies produced by individual plasmablasts from such patients neutralized different dengue variants in a mouse model. They found that the antibodies were generally more effective at neutralizing strains from initial infections rather than those involved in secondary infections. This is in keeping with an immunological model called ‘antigenic original sin’, wherein an initial encounter with a pathogen determines antibody output generated in subsequent encounters.

Importantly, the researchers found that patients with acute secondary infections were also able to successfully mount a new wave of plasmablast-mediated immune defense against the secondary strain, manifested by the generation of a collection of antibodies that effectively recognized and neutralized all four viral subtypes. More than a few very potent antibodies dominate the protective effect, according to Fink. “The immune system responds to dengue with a very diverse repertoire,” she notes. Based on the timing with which the antibodies appeared, the researchers were also able to determine that they help rather than hinder the body’s antiviral effort.

The cross-protective antibodies generated in this acute plasmablast response preferentially recognized a particular viral coat protein as a target, or ‘epitope’. If validated in larger scale studies, these results could lead to better antiviral protection. “Knowledge about antibody epitopes on the virus that are naturally targeted by the human immune response could be translated into the design of vaccines,” says Fink.

The A*STAR-affiliated researchers contributing to this research are from the Singapore Immunology Network

References

1. Xu, M., Hadinoto, V., Appanna, R., Joensson, K., Toh, Y. X. et al. Plasmablasts generated during repeated dengue infection are virus glycoprotein–specific and bind to multiple virus serotypes. The Journal of Immunology 189, 5877–5885 (2012). | article

Singapore - Increase in number of dengue cases last week

SINGAPORE - The National Environment Agency has observed an increase in the number of dengue cases last week.

There were a total of 208 dengue cases, which is unusual for January, a month that does not fall under the typical April to October peak transmission period. This is an increase from the 135 and 112 cases reported in the preceding two weeks.

NEA reminds the community to take preventive steps to remove stagnant water in their homes, such as doing the "10-minute 5-step Mozzie Wipe-out".

The total number of cases notified in 2013 (till Jan 12) is 342 - approximately a 2-and-a-half-fold increase over the same period in 2012.

This could be associated with a possible increase in the less common Dengue Type 1 (DEN-1) virus, which the community has lower immunity against.

DEN-2 is the predominant dengue serotype circulating in Singapore, showing up in 75 per cent of dengue cases sampled in the past five years, and DEN-1 serotype shows up in less than 25 per cent of sampled cases in average.

In recent months the proportion of DEN-1 cases has been increasing, with most recent results showing 30 per cent of dengue samples containing the DEN-1 serotype.

Stepping up vigilance

NEA will be stepping up its dengue prevention efforts and the public is urged to be more vigilant in keeping homes and their immediate surroundings mosquito-free.

It will deploy more manpower resources to target areas where DEN-1 has been circulating, install Gravitraps to monitor and trap the adult mosquito population, and work with grassroots to step up community outreach.

NEA has also alerted members of the Inter-Agency Dengue Task Force including LTA, HDB, PUB, NParks and Town Councils to step up their inspections of outdoor breeding habitats in the properties, buildings and development sites that they manage.

NEA will also roll out a publicity campaign to spread the vigilance message among the community.

NEA officers will also conduct house visits and distribute public educational materials such as brochures to members of the public.

In addition, residents can also participate in their grassroots' dengue prevention activities to help fight against dengue.

Urging the public to also do their part, Mr Tai Ji Choong, Director of NEA's Environment Health Department said, "Our stepped up efforts will be for naught unless the public joins in our fight against dengue. We look forward to the public's support in our efforts, so that our community can worry less about the threat of dengue".

Prevention tips to take

NEA advises all residents living in areas where dengue is transmitting to ensure their homes are free of stagnant water, apply repellent daily during daytime, and to aerosol dark corners such as underneath the bed, sofa, behind curtains in their homes every day.

Those diagnosed with dengue are encouraged to sleep in air-conditioned rooms or apply insect repellent to break the dengue transmission chain.

All other members of public should practise the "10-minute 5-step Mozzie Wipe-out" to remove mosquito breeding habitats:

1. Change water in vases/bowls on alternate days

2. Turn over all water storage containers

3. Cover bamboo pole holders when not in use

4. Clear blockages and put BTI insecticide in roof gutters monthly

5. Remove water from flower pot plates on alternate days

For the latest updates on dengue case numbers and affected areas, please visit dengue.gov.sg, or check the myENV app, or sign up for X-Dengue SMS alerts at http://www.x-dengue.com.

Members of the public who encounter mosquito breeding habitats should contact NEA's 24-hr hotline, 1800-CALL NEA (1800-2255 632), for investigation or contact their managing agents or Town Councils to have them removed.

AsiaOne