New Vaccine Approved to Protect Older Adults from Respiratory Syncytial Virus Disease

WORDS LIM TECK CHOON

AN INTRODUCTION TO RESPIRATORY SYNCYTIAL VIRUS
  • Respiratory syncytial virus (RSV for short) is a common virus that primarily infects the lungs and respiratory tract.
  • It spreads easily through respiratory droplets when an infected person coughs or sneezes.
  • The virus can survive on surfaces for several hours.
  • RSV is highly contagious and can infect almost all children by the time these children are 2 years old.
  • The virus causes cells in the respiratory tract to fuse together, forming large multinucleated cells, which is where it gets its name ‘syncytial’.


An overview of RSV disease. Click on the image to view a larger, clearer version.

For more information on RSV, catch up with Dr Lee Onn Loy in our previous article on this topic.
RSV AND ITS IMPACT ON OLDER ADULTS
FEATURED EXPERT
PROFESSOR DR AHMAD IZUANUDDIN ISMAIL
Deputy Director & Consultant Respiratory Physician
Hospital Al Sultan Abdullah Universiti Teknologi MARA (HASA UiTM)
  • RSV also significantly affects older adults. It is increasingly recognized as a major cause of respiratory illness in older adults, particularly those aged 60 and above.
  • Older adults with pre-existing conditions such as chronic obstructive pulmonary disease (COPD), heart disease, or weakened immune systems face a higher risk of developing severe outcomes from an RSV infection.
  • RSV can also worsen existing health issues, leading to conditions like congestive heart failure and worsening asthma.

“RSV can lead to severe outcomes especially among older adults with co-morbidities such as asthma, COPD and chronic heart failure,” says Professor Dr Ahmad Izuanuddin Ismail. “They also have increased risk of hospitalization following the RSV infection.”

He then elaborates: “It is important for us to protect patients aged 60 and above with co-morbidities. It is time we protect our older adults with underlying health conditions from RSV infection to enable them to lead a good quality of life especially in their golden age. By prioritizing the well-being of older adults, we can collectively foster a healthier and more vibrant society, ultimately enhancing the quality of life for all generations.”

VACCINATION AS A KEY METHOD TO REDUCE THE RISK OF SEVERE COMPLICATIONS
  • Vaccines are available to protect people against RSV.
  • Recently, GlaxoSmithKline Pharmaceutical Sdn Bhd (GSK) announced that their latest RSV vaccine for adults 60 years old or older has been approved in Malaysia.
  • The vaccine is approved based on positive data from a phase III trial, where the vaccine demonstrated high overall vaccine efficacy of 82.6% against lower respiratory tract disease.
  • This vaccine was generally well tolerated with an acceptable safety profile.
  • Some observed adverse events included injection site pain, fatigue, myalgia, and headache. These were typically mild to moderate and lasting within a few days after vaccination.

Following the approval of the vaccine, Dr Alap Gandhi, the Country Medical Director of GlaxoSmithKline Pharmaceutical Sdn Bhd (GSK) Malaysia and Brunei tells us: “Today’s announcement is a major step forward from a public health perspective, as it allows us to deliver an RSV vaccine in Malaysia to protect older adults.”

Reference: GlaxoSmithKline Pharmaceutical Sdn Bhd. (2024, September 25). GSK’s Arexvy is a vaccine approved to protect older adults from respiratory syncytial virus (RSV) disease in Malaysia [Press release, KKLIU 2755 / EXP 17.3.2025].

The Hidden Dangers of Dengue: It’s More Than Just a Fever

WORDS LIM TECK CHOON

FEATURED EXPERT
DR SHANTHI RATNAM
Consultant Physician and Intensivist
Thomson Hospital Kota Damansara

Many people think of dengue as a mild illness, but the reality can be far more serious.

Severe dengue often requires hospitalization and can lead to internal bleeding, organ damage, and even death. What’s more, a second infection is more likely to be severe.

However, there’s another aspect of dengue that’s less well-known: post-dengue syndrome. This condition can leave lasting effects long after the initial infection has passed.

BAHWANEE’S LONG ROAD TO RECOVERY

Bahwanee Muthusamy’s experience with dengue fever was the beginning of a challenging journey that has lasted over 6 months.

“This was my second bout of dengue,” Bahwanee recalls. “At first, it seemed like just a mild fever but within a day, I had a terrible headache, vomiting, and diarrhoea. My platelet count dropped dangerously low.”

Bahwanee’s condition quickly became critical, affecting her liver. She spent 2 weeks in the hospital and another 2 months on medical leave.

Even simple tasks like driving or sitting up for long periods were impossible due to nerve compression in her lower back.

WHAT IS POST-DENGUE SYNDROME?

Dr Shanthi Ratnam explains that Bahwanee’s experience is known as post-dengue syndrome (PDS).

“It’s when symptoms of dengue fever persist for more than 6 weeks after the acute phase,” she says. “We’re still learning about how common it is, but some studies suggest it could affect between 18% and 50% of dengue patients.”

Dr Shanthi is an intensivist, a medical practitioner that specializes in the care of critically ill patients, such as those in the intensive care unit or ICU.

PDS can cause a range of symptoms, including:

  • Mild to overwhelming fatigue
  • Muscle and joint pain
  • Swelling of the joints (reactive arthritis)
  • Poor concentration
  • Dizziness

The challenge with PDS is that there’s no specific test to diagnose it. Doctors must rule out other possible causes before concluding that a patient has PDS.

LONG-TERM IMPACT OF PDS

PDS has turned Bahwanee’s life upside down.

“It’s affected everything,” she says. “Simple actions like climbing stairs are now exhausting. I can’t work like I used to. I’m dealing with hormonal issues, hair loss, and a weakened immune system. It’s been a nightmare.”

Dr Shanthi points out that PDS can also take a toll on mental health.

“It can severely affect a person’s quality of life,” she explains. “This is true especially for young, active people. The constant fatigue, pain, and inability to resume normal activities can be depressing.”

WHO IS AT RISK OF PDS?

While anyone can develop PDS, some groups are at higher risk:

  • Elderly patients
  • People with existing health conditions like hypertension, heart disease, obesity, or autoimmune diseases
  • Those who have had dengue before
RECOVERING FROM PDS

For people that are recovering from dengue, Dr Shanthi recommends the following:

  • Get plenty of rest. It is good to get 8 to 10 hours of sleep per night.
  • Eat a balanced diet rich in fruits and vegetables.

She also offers advice for caregivers of the following groups of people.

  • Children. Keep them home from school for a week before gradually resuming normal activities.
  • Older adults. Encourage frequent naps and sufficient nighttime rest.
  • People with diabetes or high blood pressure. Monitor blood pressure closely and consult with a doctor about medication adjustments.
  • People at high risk of bleeding. Watch for warning signs like dark, sticky stools.
GIVEN THE LONG-TERM IMPACT OF DENGUE, PREVENTION IS CRUCIAL

Dr Shanthi emphasizes the need for a comprehensive approach such as:

  • Eliminate mosquito breeding grounds, such as standing water in containers and rain gutters.
  • Consider innovative preventive strategies like the dengue vaccine.
About the Dengue Vaccine

The dengue vaccine, recently approved in Malaysia, is now available in private clinics and hospitals.

It’s given in 2 doses, 3 months apart.

Dr Shanthi recommends it for high-risk groups such as:

  • Elderly people with other health conditions
  • Obese individuals
  • People with high blood pressure, heart disease, or autoimmune conditions
  • People taking medications that can affect their immune system

Even those who have had dengue before, like Bahwanee, can get the vaccine 6 months later for protection against other strains of the dengue virus.

A CALL TO ACTION

Both Dr Shanthi and Bahwanee stress the importance of taking dengue seriously.

“We need to renew our commitment to fight dengue on all fronts,” says Dr Shanthi.

Bahwanee adds: “Dengue is often dismissed as merely a fever but look at what happened to me. I’m so glad there’s a dengue vaccine now because dengue is everywhere, so no one is safe. We need to take it seriously and be proactive to combat this threat together.”

Stay Safe, Stay Protected: Malaysia’s MyPELINDUNG Campaign for COVID-19

WORDS LIM TECK CHOON

Recently, the Malaysian Society of Infection Control and Infectious Diseases (MyICID), the National Cancer Society of Malaysia (NCSM), the Malaysian Red Crescent (MRC), and Diabetes Malaysia (DM), in partnership with Pfizer Malaysia, extended the MyPELINDUNG campaign under the theme Lindungi Malaysia, Sihat Bersama.

The campaign emphasizes the need for continued vigilance, vaccinations, and timely medical treatment in the fight against COVID-19.

THE NATIONAL LAUNCH OF MyPELINDUNG

This prestigious launch event saw many key figures coming together to highlight the importance of the campaign.

“As we adapt to living with COVID-19, staying proactive is key. Vaccinations, following health guidelines, and seeking prompt medical advice are crucial in keeping our communities safe,” said Dato’ Danial Iskandar, the Deputy Secretary General of MRC.

FAMILIAR FACES LEAD THE CHARGE

This year’s campaign featured well-known personalities from different walks of life, each advocating for public health and safety in unique ways:

  • Media personalities Atilia Haron and Aishah Sinclair, representing the sandwich generation, highlighted the importance of protecting both children and elderly parents, particularly their own vulnerable parents, Salamiah Hassan and Dida Sinclair.
  • Veteran actor Dato’ Jalaludin Hassan advocated for older adults, especially those with pre-existing conditions, stressing timely medical care and continued caution.
  • Dr Say Shazril focused on parents protecting their children, emphasizing vaccinations and preventing disruption to education and social life.
  • Actress Fasha Sandha shared her personal experience of how COVID-19 disrupted her family reunion during Hari Raya Puasa, underscoring the virus’s potential to change cherished moments.
  • Comedian Douglas Lim talked about the challenges of work-related travel in the era of COVID-19, advocating for health and safety while on the go.
VACCINES ARE YOUR SHIELD AGAINST SEVERE COVID-19

Vaccinations remain a powerful defense against severe illness, hospitalization, and death.

Staying up to date with your COVID-19 vaccines is essential, particularly for the elderly, individuals with underlying health conditions, and children.

“COVID-19 is here to stay. Vaccinations are critical in preventing severe illness and reducing hospitalizations, especially for those at higher risk,” said Dr Shaharudeen Kamaludeen, the President of MyICID.

EARLY TREATMENT IS A CRITICAL STEP FOR HIGH-RISK GROUPS

For individuals aged 60 and older or those with medical conditions like diabetes and chronic lung disease, the risk of severe COVID-19 remains high.

Hence, early treatment is key. Consulting with healthcare professionals immediately upon testing positive can improve the management of the illness and provide peace of mind for families.

“Early treatment, even for mild symptoms, is crucial. It reassures families and helps manage the illness more effectively,” said Dato Dr Saunthari Somasundaram.

Dr Mohazmi, the Secretary-General of DM, echoed her statement and emphasized the importance of starting treatment as soon as possible to reduce severe outcomes.

GET INVOLVED TO PROTECT YOURSELF AND YOUR LOVED ONES

The MyPELINDUNG campaign continues to reach Malaysians through digital platforms like Facebook, with engaging content, live streams featuring medical experts, and community outreach events.

“MyPELINDUNG reflects our commitment to public health, ensuring that essential healthcare information reaches every Malaysian,” said Deborah Seifert, the Cluster Lead of Pfizer Malaysia, Singapore, Indonesia & the Philippines.

Stay connected with the MyPELINDUNG campaign by following their official Facebook page (link opens in a new tab) for updates and helpful resources.

ASEAN Unveils Groundbreaking Platform to Combat Airborne Infections and Boost Pandemic Preparedness

WORDS LIM TECK CHOON

On 8 August 2024, the 16th ASEAN Health Ministers Meeting (AHMM) witnessed the launch of a pioneering initiative set to transform the region’s approach to airborne infections and pandemic readiness. This milestone took place in Vientiane, Laos.

KEY HIGHLIGHTS
  • The Airborne Infection Defense Platform (AIDP) was officially launched.
  • The platform focuses on strengthening tuberculosis response and overall pandemic preparedness.
  • It is supported by United States Agency for International Development (USAID) and implemented by Stop TB Partnership and Stop TB Partnership Indonesia with the endorsement of ASEAN member states.
THE AIDP: A RESPONSE TO URGENT HEALTH CHALLENGES

The AIDP emerges as a critical solution to address the growing threat of airborne respiratory infections across ASEAN.

With more than 2.4 million people affected by tuberculosis in the region, and five ASEAN countries on the WHO’s high burden tuberculosis list, the need for a coordinated response has never been more pressing.

  • In Malaysia, there were 26,781 cases in 2023, a 5.47% increase from 2022.
  • In the ASEAN region, there was an estimated increase of nearly 500,000 additional deaths from 2020 to 2022 due to COVID-19 disruptions.

The AIDP aims to:

  • Enhance cooperation among ASEAN member states,
  • Agree on policies and methodologies.
  • Exchange learnings and resources.
  • Create surge capacity for tuberculosis cases.
  • Improve overall pandemic preparedness.

The objectives would be carried out via a two-phase approach:

  • Landscape assessment. Evaluate the current capacities of 10 ASEAN countries.
  • Strengthening initiatives. Support community-based and primary health care activities

The AIDP will utilize cutting-edge technologies such as:

  • Portable digital X-rays.
  • Rapid molecular diagnostic platforms.
  • Real-time digital surveillance tools.
A VISION FOR A RESILIENT HEALTH SYSTEM

His Excellency Dr Bounfeng Phoummalaysith, Minister of Health of the Lao People’s Democratic Republic, emphasized the importance of learning from the COVID-19 pandemic.

“We must create a stronger and more resilient system. The TB program has several management principles that can be easily adopted for any airborne disease. We need to invest in platform technologies and create infrastructure that can be deployed for future airborne pandemics,” he said.

Professor Tjandra Yoga Aditama MD, the Stop TB Partnership Indonesia Senior Advisor and AIDP Project Lead, stressed the importance of regional cooperation: “The condition of tuberculosis in ASEAN is quite concerning. This demonstrates the importance of working with ASEAN to strengthen the TB response system to not only create surge capacity for TB cases but also enhance pandemic preparedness.”

Additionally, Dr Suvanand Sahu, the Deputy Executive Director of the Stop TB Partnership, highlighted the project’s potential impact. “The first phase will improve understanding by carrying out a landscape assessment across 10 ASEAN countries. Our second phase will support initiatives to strengthen the preparedness capacity of TB responses across ASEAN,” he said.

His Excellency Dr Teodoro Herbosa, the incoming Stop TB Partnership Board Chairman, added that investing in tackling one airborne infection, such as tuberculosis, is an investment into tackling all airborne infections.

The launch of the AIDP marks a significant step forward in ASEAN’s commitment to public health and pandemic preparedness. As the region continues to grapple with the challenges posed by airborne infections, this innovative platform offers hope for a more resilient and responsive health system.

Has Malaysia Bent the Curve in the Fight Against Hepatitis B & C?

WORDS LIM TECK CHOON

FEATURED EXPERT
DR PHILIP PANG BOON CHEONG
Consultant Gastroenterologist and Hepatologist
Subang Jaya Medical Centre
A QUICK OVERVIEW OF HEPATITIS B & C
Hepatitis B
  • It’s a viral infection that attacks the liver.
  • It’s caused by the hepatitis B virus (HBV)
  • Can be acute (short-term) or chronic (long-term).
  • Transmitted through blood, semen, and other body fluids.
  • Currently, there is no cure available.
  • Vaccination provides a greater degree of protection against HBV infection.
Hepatitis C
  • It’s also a viral liver infection.
  • It’s caused by the hepatitis C virus (HCV).
  • It often becomes chronic or long-term.
  • Primarily transmitted through blood-to-blood contact.
  • No vaccine available, but treatable with direct-acting antiviral medications (97% cure rate).
WHY IS THERE A FIGHT AGAINST HEPATITIS B & C?

Dr Philip Pang reveals the following:

  • Hepatitis B and C are considered silent killers because they are often undiagnosed until health complications arise.
  • These diseases progress while undetected to cause severe liver damage and even cancer.

“Viral hepatitis is preventable and treatable. Thus, it is crucial that effective intervention measures are put in place,” Dr Pang shares.

HOW DO WE FIGHT AGAINST THESE TWO FORMS OF HEPATITIS?
  • 3 doses of the hepatitis B vaccine are administered to all newborns before they turn 1.
  • “The Ministry of Health (MOH) has also implemented targeted health screenings for high-risk populations including pregnant women and those with family history,” says Dr Pang.
  • Wider access to affordable direct-acting antivirals has led to a significant drop in chronic hepatitis C cases.
  • The Ministry of Health has also developed the National Strategic Plan for Hepatitis B and C (NSPHBC) 2019-2023 with the aim of eliminating hepatitis B and C by 2030. This comprehensive plan outlines a structured approach to prevention, diagnosis, treatment, and care to combat viral hepatitis.
HOW ARE WE DOING THUS FAR?
  • Statistics show that in Malaysia, an estimated 1.1% of the population is infected with hepatitis B virus in 2017, and 2.5% with hepatitis C virus in 2019.
  • Viral hepatitis is the seventh most common cause of mortality in our country.
  • 94% of deaths from chronic hepatitis B and C infections are caused by cirrhosis (severe scarring of the liver) and liver cancer.
THE DRIVE FOR GREATER PREVENTION OF HEPATITIS B

Hepatitis B is not curable at the moment, although early diagnosis can allow for proper measures to be taken so that individuals with this disease can still lead a fairly active and productive life.

However, many individuals with hepatitis B are unaware of their status and often go undiagnosed.

“An individual with hepatitis B is like having a neighbour who lives together in harmony, but you don’t know when your neighbour would one day go crazy,” Dr Pang tells us.

He goes on to say: “If we can fight hepatitis B in this generation, we are well on our way to eliminating it by 2030. Yet, we are far from achieving this goal. More needs to be done to raise public awareness about hepatitis B transmission, prevention methods, and the importance of vaccination.”

Pregnant Moms

The lack of symptoms can lead to pregnant mothers being unaware that they have hepatitis B, which increases the risk of mother-to-child transmission.

Routine blood tests during pregnancy can help identify these cases.

“Early detection allows for proper management, Pregnant mothers may be given antivirals and newborns given an immunoglobulin injection, specifically hepatitis B immunoglobulin, within 24 hours after birth” Dr Pang says.

For the newborn, the immunoglobulin injection provides a temporary protection against hepatitis B infection until the baby’s own immune system can develop immunity through vaccination.

People Living with Hepatitis B

Dr Pang recommends that individuals with hepatitis B should see their doctors once a year and undergo a routine blood test, which monitors their viral load.

Those who are 40 years old and above and present with symptoms should see their doctors more often, every six months, and undergo liver cancer surveillance.

Consider Hepatitis Vaccination and Stay Safe
  • Vaccination is key for improving our protection against hepatitis A and B.
  • Practice safe sex and good hygiene are vital.
  • Avoid sharing needles and personal care items.
  • Ensure safe practices during procedures that involve needles, such acupuncture or tattooing.

Let’s Talk about HPV with a Doctor

WORDS DR RAHIMAH RAHIM

FEATURED EXPERT
DR RAHIMAH RAHIM
Medical Doctor
Klinik Amaya
Question 1
WHAT IS HPV?

The human papilloma virus or HPV is a very common virus transmitted through skin-to-skin contact, including sexual activity.

Most HPV infections do not cause any symptoms and can clear up on their own.

However, some strains can lead to serious health issues like genital warts and cancers, particularly cervical cancer.

The risk of HPV infection increases with certain behaviors such as having multiple sexual partners, engaging in unprotected sex, and smoking.

How HPV infects human cells. Click on the image for a larger, clearer version.

Question 2
IF HPV INFECTION CAN SHOW NO SYMPTOMS, WHAT CAN WE DO TO FIND OUT WHETHER WE HAVE BEEN INFECTED?

Screening for HPV is vital because it helps detect abnormal cell changes early, before they have the chance to progress into cancer.

Cervical screening, which includes HPV testing, is essential for identifying high-risk HPV strains.

High-risk HPV strains can lead to abnormal cell changes in the cervix, which, if left untreated, may progress to cancer. Hence, early detection through HPV testing allows for close monitoring and timely intervention, preventing the development of cervical cancer. This proactive approach is essential in maintaining women’s health and well-being.

Question 3
CAN YOU TELL US ABOUT THE HPV VACCINE?

The HPV vaccine is the most effective way to prevent HPV infections and the associated cancers.

It is safe, effective, and recommended for both males and females starting at age 9.

The vaccine is administered as a series of shots and provides protection against several high-risk HPV strains.

Vaccination, combined with safe sex practices, using condoms or dental dams, and limiting the number of sexual partners, greatly reduces the risk of HPV transmission.

Question 4
WHAT ARE THE TREATMENT OPTIONS AVAILABLE FOR PEOPLE WITH HPV?

Healthcare providers can offer comprehensive guidance on screening, diagnosis, and treatment options for those affected by HPV infections.

This includes regular monitoring for abnormal cell changes, treatment for genital warts, and appropriate interventions for any pre-cancerous conditions.

Digital health solutions can be leveraged to enhance our approach in managing HPV. These solutions facilitate seamless patient-doctor interactions, enabling us to schedule and conduct HPV screenings efficiently. Patients can conveniently access consultations and receive timely reminders for screenings, which are crucial for early detection. This technology not only streamlines our workflow but also empowers patients to take proactive steps in their healthcare journey.

For further information, individuals can consult with healthcare professionals. Our goal is to provide comprehensive care and support to those affected by or at risk of HPV.

 

Why Is the Dengue Vaccine Needed? An Associate Professor Answers More Questions About the Vaccine

WORDS ASSOCIATE PROFESSOR DR VERNA LEE KAR MUN

FEATURED EXPERT
ASSOCIATE PROFESSOR DR VERNA LEE KAR MUN
Family Medicine Specialist
IMU Healthcare
WHY IS THE QDENGA VACCINE NECESSARY? WE ALREADY HAVE PREVENTIVE MEASURES SUCH AS FOGGING TO PREVENT THE AEDES MOSQUITO FROM BREEDING.

Fogging is effective in killing the Aedes mosquitoes. Its effect is immediate, extending to an average of 72 hours.

Fogging Works, but There Are Some Drawbacks

While fogging has been the main means to mitigate dengue infection in Malaysia, however, health offices are usually informed after the infection have been notified. As a result, fogging by itself does not reduce severe dengue infection that requires hospitalizations.

Furthermore, the resistance of the Aedes mosquitoes to insecticides is increasing. This decreases the effectiveness of fogging to control the population of these mosquitoes.

The Role of Dengue Vaccines

On the other hand, dengue vaccines have been proven to be effective in reducing the numbers of severe dengue infection requiring hospitalizations.

THERE WAS SOME CONTROVERSY WITH REGARDS TO THE SAFETY PROFILE OF THE PREVIOUS DENGUE VACCINE. SHOULD WE BE CONCERNED ABOUT THE QDENGA VACCINE?

Just like any new drug or new medical technology, there is very limited data from clinical practice in the early days. There would be many concerns.

Dengvaxia, the First Dengue Vaccine

The first dengue vaccine, Dengvaxia, was approved in April 2018.

It is safe in persons who have had dengue virus infection in the past (seropositive individuals), but it also increases the risk of severe dengue in those who experience their first natural dengue infection after receiving their vaccination (seronegative individuals).

Hence, pre-vaccination screening for past dengue infection is recommended before one receives the Dengvaxia vaccine. Only people with evidence of past dengue infection—indicated by the presence of dengue IgG antibody in their blood—would receive this vaccination.

About the Newest Vaccine, Qdenga

A second vaccine for dengue, Qdenga, received prequalification from the World Health Organization (WHO) on 10 May 2024.

Is it safe?

  • Overall, during the clinical trials, the vaccine was well tolerated. The most frequent reported vaccine-related adverse events were injection site itchiness, bruising, and fever.
  • An excess of hospitalized dengue virus serotype 3 (DENV3) infections was reported among baseline seronegative children, but it was not statistically significant.
  • There was also an excess of cases of severe dengue among seronegative vaccinees, all of which were caused by DENV3, but, again, the difference was not statistically significant.
  • An increase in the risk of dengue infection requiring hospitalization or severe dengue due to DENV3 in vaccinated seronegative subjects cannot be conclusively ruled out. We probably need to wait for more data.

How about allergy reactions?

During the clinical trial, no cases of severe allergy reaction or anaphylaxis were observed.

However, cases of anaphylaxis associated with this new vaccine occurred following the vaccine’s introduction to children between the age of 10 and 14 years in Brazil since February 2024, with 16 cases were reported (4.4/100,000 doses administered), including 3 cases of anaphylactic shock (0.8/100,000 doses administered).

The currently approved package insert for the vaccine describes precautionary measures to mitigate the risk of anaphylaxis. A full assessment of the national immunization programme is underway.

THE QDENGA VACCINE IS SAID TO BE ABLE TO IMMUNIZE AGAINST ALL FOUR SEROTYPES OF DENGUE VIRUS. WHY IS THIS A GOOD THING?

Dengue viruses belong to the genus Flavivirus.

The dengue virus. Click on the image for a larger, clearer version.

Flaviviruses are lipid-enveloped, single-stranded RNA viruses. The structural pre-membrane (prM) and envelope (E) proteins are embedded in the lipid envelope and are displayed on the surface of virions.

There are 4 dengue virus serotypes (DENV1, DENV2, DENV3, and DENV4); the serotypes share structural proteins (prM and E) but are genetically and serologically distinct.

Infection with 1 serotype induces sustained protection against the same serotype only. Although uncommon, an individual without a vaccine can be infected by each serotype for a total of 4 infections during their lifetime.

Serotypes and Infections

People who acquire a second dengue infection caused by a different serotype are at a higher risk for severe dengue once cross-protection induced by the first infection wanes.

Potential mechanisms for increased risk of severe dengue caused by a second infection include:

  • Cross-reactive antibodies binding to a different DENV serotype, which then enable uptake in inflammatory cells. This leads to higher and more prolonged virus count in the blood circulation (higher temperature and prolonged fever) that induces imbalanced pro-inflammatory and anti-inflammatory responses often referred to as antibody-dependent enhancement.
  • The action of the non-structural protein 1 (NS1) on the blood vessel wall or endothelium can trigger the release of active chemicals from immune cells.
  • Both the above will result in endothelial hyperpermeability and vascular leak (leading to hypovolemic shock and bleeding).

How the Vaccine Is Beneficial

Both dengue vaccines are tetravalent live-attenuated vaccines.

The new vaccine, Qdenga, induces a broad spectrum of immune responses which include:

  • Neutralizing antibodies with a 50% reduction against all 4 dengue virus serotypes.
  • Cross-reactive antibodies that block the activity of the NS1 protein.
  • Type-specific memory B cells to all four serotypes.

This means the vaccine can protect us from severe dengue infection by all the 4 serotypes. This is a good thing.

Expert Answers All the Important Questions You Have about the New Dengue Vaccine

WORDS LIM TECK CHOON

With the Qdenga® dengue vaccine officially launched by pharmaceutical company Takeda Malaysia in Malaysia on 11 June 2024, we manage to get some important answers from Dr Goh Choo Beng about dengue and this vaccine.

FEATURED EXPERT
DR GOH CHOO BENG
Head of Medical Affairs
Takeda India & Southeast Asia
What does it do?

Prevention of dengue caused by any of the 4 dengue serotypes.

The clinical trial of the vaccine found that it can:

  • Prevent 80.2% of symptomatic dengue cases at 12 months after receiving the vaccination.
  • Prevent 90.4% of hospitalizations at 18 months after vaccination.
Who can receive the vaccine?

Qdenga® can be administered to individuals 4 years old and above.

How many doses do I need?

Two doses. The second dose will be given three months after the first dose.

Where can I get it?

Currently it’s available at general practitioner or GP clinics as well as private hospitals.

How much is the vaccine?

The price will be set by the clinic or the hospital, so it’s best to consult them about the price.

How does this vaccine work?

Dr Goh explains that the Qdenga® vaccine has a backbone that is based on the live-attenuated DENV2 serotype of the dengue virus, with recombinant strains expressing surface proteins for DENV1, DENV3 and DENV4.

This way, the vaccine will protect an individual from all 4 dengue serotypes.

Is it safe for individuals that have not contracted dengue before?

Yes. People that have no history of dengue fever as well as people that have had dengue can safely receive the vaccine.

No blood tests are necessary before receiving the vaccine.

What are the side effects?

Short term side effects are common ones associated with vaccination, such as redness and soreness at site of injection. These side effects are mild and temporary.

At the time of writing, there is an ongoing clinical trial that is monitoring and closely following selected individuals that have received the vaccine since about 4.5 years ago. So far, the investigators have found that:

  • The protection afforded by the vaccine persists 4.5 years after receiving the vaccine.
  • There is no long-term serious side effect seen so far.

A Neurologist Discusses the Link Between COVID-19, Younger Adults, and Stroke

WORDS DR JOYCE PAULINE JOSEPH

FEATURED EXPERT
DR JOYCE PAULINE JOSEPH
Consultant Neurologist
Aurelius Hospital Nilai

The COVID-19 pandemic has fundamentally altered the physiological landscape of individuals around the globe. The virus has demonstrated its ability to traverse various bodily functions, leaving a trail of physiological changes in its wake. From the intricate dynamics of the immune response to cardiovascular issues, COVID-19 has brought about unprecedented impacts on human health in various ways.

But what are the correlations, if any, between COVID-19 and an increase in stroke incidences especially amongst the young? In light of the increasing number of cases of COVID-19 in Malaysia again, we attempt to investigate the links.

THE LINK TO STROKE

Traditionally, when we speak about strokes, it tends to be an “elderly persons” disease, a health concern prevalent amongst those aged 50 and above.

However, over the past 3 years since the first outbreak of COVID-19 pandemic, a worrying connection has emerged between the virus and incidences of strokes in younger individuals.

COVID-19 is associated with a higher risk of stroke, a majority of them being ischaemic strokes caused by a blockage in an artery that supplies blood to the brain.

A study suggested a connection between the high prevalence of vascular risk factors and concurrent elevation of proinflammatory and procoagulation biomarkers in this.

In the same study, it has been proposed that the virus that causes COVID-19 infects the cells that line the inside of the blood vessels.

These infected cells release several pro-inflammatory factors that attract other immune cells to the affected area.

In turn, this leads to damage to the lining cells, activating platelets and other factors involved in clotting.

This chain of events eventually increases the risk of a blood clot that could potentially travel up to the brain and cause a stroke.

Hypercoagulability and inflammatory response cause vascular complications, increasing the risk of strokes, regardless of age.

Findings from another large-scale study suggested that COVID-19 is a risk factor for deep vein thrombosis, pulmonary embolism, and bleeding.

The risk of developing blood clots in the lungs and legs is significantly elevated for up to 6 months upon contracting COVID-19.

After the initial 30 days of infection, individuals afflicted with COVID-19 displayed heightened susceptibilities and endured a year-long burden of newly emerging cardiovascular conditions.

These conditions range from cerebrovascular issues and dysrhythmias to inflammatory heart disease, ischaemic heart disease, heart failure, thromboembolic disease, and assorted cardiac disorders.

Strikingly, these risks manifested consistently across various demographic factors, such as age, race, and gender, as well as other established cardiovascular risk factors like obesity, hypertension, diabetes, chronic kidney disease, and hyperlipidemia.

Notably, even those without any pre-existing cardiovascular conditions prior to exposure to COVID-19 exhibited these risks, suggesting a propensity for these complications to manifest in individuals traditionally considered at low risk for cardiovascular diseases.

IN SUMMARY

The data and evidence gathered do point to a heightened risk of stroke brought about by COVID-19, regardless of age.

Even though it remains an uncommon occurrence, it remains a risk especially for individuals pre-existing health conditions that are known to boost the risk of stroke.

While the correlation between incidences of stroke, COVID-19 and how it affects younger individuals remains a subject of ongoing research and study, it remains crucial in recognizing the potential risks and taking appropriate and proactive measures.

References:

  1. Mbonde, A. A., O’Carroll, C. B., Grill, M. F., Zhang, N., Butterfield, R., & Demaerschalk, B. M. (2022). Stroke features, risk factors, and pathophysiology in SARS-CoV-2-infected patients. Mayo Clinic proceedings. Innovations, quality & outcomes, 6(2), 156–165. https://doi.org/10.1016/j.mayocpiqo.2022.01.003
  2. Xie, Y., Xu, E., Bowe, B., & Al-Aly, Z. (2022). Long-term cardiovascular outcomes of COVID-19. Nature medicine, 28(3), 583–590. https://doi.org/10.1038/s41591-022-01689-3

Tuberculosis Cases Are Rising in Malaysia. An Expert Shares What You Should Know & Do About This

WORDS LIM TECK CHOON

FEATURED EXPERT
DR ROSMADI ISMAIL
Consultant Interventional Pulmonologist and Internal Medicine Specialist
Sunway Medical Centre

Quite recently, our Minister of Health Dr Zaliha Mustafa revealed at the United Nations General Assembly High-Level Meeting that there was a concerning increase of 17% in tuberculosis cases in 2022 compared to 2021, along with a 12% increase in tuberculosis-related deaths during that time period.

In light of this development, Dr Rosmadi Ismail shares his thoughts with us about tuberculosis, its detection, treatment, and prevention.

Tuberculosis is an infectious disease that is caused by the bacteria Mycobacterium tuberculosis (MTB) infecting the lungs as well as certain other parts of the body.

An overview of the symptoms and preventive measures of tuberculosis. Click on the image for a larger, clearer view.

IS DETECTION OF TUBERCULOSIS GETTING BETTER?

Dr Rosmadi reveals that there are several innovative techniques currently undergoing clinical trials in a few countries.

These techniques, which include biosensing technologies and nano-diagnostics, promise quicker and more accurate results.

He shares: “Ongoing research focuses on innovative methods like computer-aided detection (CAD) through artificial intelligence, aerosol capture technologies, and antigen-based skin tests. They are poised to revolutionise TB diagnosis, enhancing efficiency and effectiveness in the future.”

In Malaysia, there are diverse methods employed to ensure accurate and timely detection of tuberculosis, such as:

  • Sputum smear microscopy, typically the first test for tuberculosis.
  • Culture and sensitivity testing to diagnose tuberculosis.
  • Nucleic acid amplification tests (NAATs) to facilitate the identification of tuberculosis cases.
  • Chest radiography and clinical tests like the Tuberculin Skin Test (TST) to confirming the infection.
TREATMENT OF TUBERCULOSIS

Treatment of tuberculosis in Malaysia follows the World Health Organization guidelines, which is the global standard.

Dr Rosmadi tells us, “The standard treatment for drug-susceptible tuberculosis in Malaysia involves a combination of four drugs administered for a duration of 6 to 8 months.”

Treatment utilizes the Directly Observed Treatment (DOT) strategy, which sees the patients receiving close supervision from healthcare workers to ensure that they complete their medication intake.

Currently, there are no new medications or treatments that show superior results over current ones when it comes to treating tuberculosis. Dr Rosmadi notes that treatment for drug-resistant TB involves a distinct medication regimen and extended treatment duration.

“This tailored approach has proven effective even in cases of drug-resistant TB, reinforcing our commitment to comprehensive patient care,” he says.

DR ROSMADI’S TUBERCULOSIS TIPS 
  • Stay clear of crowded places. It’s best to avoid crowds, especially if they’re poorly ventilated.
  • If you’re experiencing a persistent cough, fever, or unexpected weight loss, seek medical help promptly. This will help you get better and stop the disease from spreading.
  • Get checked if you’re at risk. If you have a weak immune system or have been around people with tuberculosis, consider getting tested. It’s a simple step that can catch the disease early if exposed.
  • If you’re diagnosed with tuberculosis, completing your treatment is essential. P
  • Preventive measures such as wearing a mask, covering your mouth and nose when you cough or sneeze, and disposing of tissues properly can help protect yourself and those around you.
  • If your job puts you in contact with many people, wear the proper protective gear as an added layer of safety.
  • Think about getting vaccinated. The current vaccine, Bacillus Calmette Guérin (BCG), offers partial protection to infants and young children against severe forms of tuberculosis. It doesn’t protect adolescents and adults that are the primary carriers of the tuberculosis bacteria, but it could help in the long run.