Dengue 3 in Singapore

Dengue 3 in Singapore

Dr KK Aggarwal

In Singapore a total of 15,998 dengue cases were reported last year, almost five times the number for 2018. However, the figure is lower than the annual numbers reported in 2013 and 2014.

The surge in dengue cases in 2019 may be attributable to several factors – including a high Aedes aegypti mosquito population, warmer weather and low population immunity.

The less common dengue-3 serotype has been detected in more clusters across the island, including at the large clusters of Jalan Bangau near Yio Chu Kang, Cashew Road in Bukit Panjang and Jalan Paras in Chai Chee.

As Singapore has not seen a dengue-3 outbreak in the last three decades, the population immunity for dengue-3 is low and therefore more susceptible to transmission of the virus.

Since 2016, Singapore has seen mostly cases of the dengue-2 serotype. As of Monday, there were 107 active dengue clusters in Singapore.

Dengue Vaccine : The Asian Concerns

Dengue Vaccine : The Asian Concerns

Dr KK Aggarwal

President CMAAO and HCFI

The Health Minister Dr Harsh Wardhan told the parliament that India is near ready for the dengue vaccine. Let us know the facts

Indian Scenario

1.      A live attenuated vaccine known as Dengvaxia, developed by Sanofi, was licensed in 2015. Following this, long-term follow-up of the Sanofi phase III efficacy trial participants has revealed potential safety concerns.

2.    This vaccine, which appears to predispose dengue-naïve recipients to an increased risk of hospitalization in the future, is recommended by the WHO only for adults with a history of prior dengue virus infection.

3.    India is poised now to test out two different dengue vaccine candidates in clinical trials in the near future, an LAV, TetraVax-DV, and a recombinant protein-based vaccine, DSV4.

4.    All current tetravalent LAV approaches are based on physical mixtures of empirically determined amounts of four monovalent vaccine viruses. Such mixtures manifest a tendency of viral interference and could simulate a monotypic infection. In such a situation, seronegative recipients may be potentially sensitized to antibody-dependent enhancement (ADE) later in life, upon natural DENV infection.

Scientific facts

1.     Infection with one DENV type provides long-term protection against reinfection with that same type, supporting the feasibility of an effective dengue vaccine.

2.      Also following infection with one type, there is short-lived immunity and cross-protection against disease caused by the other three DENV types.

3.     But in view of the association between previous exposure to DENV types and severe disease, and the recognition that all four DENV types are capable of causing severe disease, ideally any candidate vaccine should produce protective immunity against all four DENV types (tetravalent immunity).

Concerns

1.     Can India afford ruling out prior infection in every case before giving the vaccine?

2.     Will the tetravalent vaccine not produce ADE?

3.     Will the vaccine be cost effective?

4.     Given that the rate of clinically relevant third or fourth DENV infection is low, do we require tetravalent immunity?

5.     Since waning immunity might also increase the risk for severe disease in vaccine recipients the aim should be only to have long lived vaccine-induced protective immunity.

Diagnostic testing of concurrent suspected dengue or Zika in symptomatic patients

Dr KK Aggarwal

The United States Centers for Disease Control and Prevention (CDC) has issued updated guidance for diagnostic evaluation of Zika and dengue virus infection in symptomatic patients. According to the guideline, nucleic acid amplification tests (NAATs) are the preferred method of diagnosis for patients with suspected dengue or Zika virus disease. 

The key recommendations are:

·         For symptomatic nonpregnant persons, dengue and Zika virus NAATs should be done on serum collected ≤7 days after symptom onset. A positive NAAT in symptomatic persons with possible exposure to dengue and Zika virus typically provides evidence of acute infection, and no antibody testing is indicated.

·         If NAAT is negative or serum is collected >7 days after symptom onset, dengue and Zika virus IgM antibody tests should be done.

·         Positive IgM antibody test results with negative NAAT results should be confirmed by neutralizing antibody tests when clinically or epidemiologically indicated, including for all pregnant women.

·         Pregnant women with a clinically compatible illness and recent possible exposure to dengue and Zika virus should have concurrent diagnostic testing for dengue and Zika virus infection performed by NAAT and IgM antibody testing on a serum specimen and NAAT on a urine specimen to diagnose Zika virus infection 

·         If either dengue or Zika virus IgM antibody testing is positive without a positive NAAT or NS1 antigen test, and definitive diagnosis is needed for clinical or epidemiologic purposes, confirmatory Plaque reduction neutralization tests (PRNTs) should be performed against dengue, Zika, and other flaviviruses endemic to the region where exposure occurred.

(Source: MMWR Recomm Rep. 2019 Jun 14; 68(1): 1–10).

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Past National President IMA

Malaria to be made notifiable disease

Monsoons bring welcome relief from the scorching heat, but they also bring with them a host of illnesses, notably dengue, Chikungunya.

In a meeting held to review the preparedness for prevention and control of vector borne diseases (malaria, dengue, and chikungunya) in the national capital, the Union Health Minister, Dr Harsh Vardhan urged the state government and the Mayors to work towards making hospitals, schools and government buildings 'Vector-Free'.

He also suggested that Malaria should be made a notifiable disease, which was assured by the Delhi Health Minister.

In the meeting, it was also suggested that all hospitals, including the private ones, should appoint a nodal person for vector-borne diseases to ensure that the Government and private interventions and efforts to prevent/ cure vector-borne diseases are in tandem. The focus should be on active case finding of cases and reduction of vectors.

What each doctor can do

 ·         Ask every suspected case of dengue, chikungunya or malaria to trace the mosquito breeding site in the vicinity of 50 houses.

·         Surgical strikes on all the mosquitoes in the vicinity of identified cases can make the difference.

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Past National President IMA

Top health concerns of 2019

Air pollution

Nine out of ten people now breathe polluted air, which kills 7 million people every year, according to the World Health Organization (WHO). And it’s just not outdoor air pollution; household (indoor) air pollution also causes 4 million deaths annually.

Air pollution has now emerged as a major environmental risk factor for health; particulate matter (PM 2.5/10), ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2) are pollutants with the strongest evidence for public health concern. It not only contributes to chronic illnesses but also acute cardiovascular and respiratory events such as stroke, heart attack, acute asthma attack and acute exacerbation of COPD. The WHO further says, “The health effects of air pollution are serious – one third of deaths from stroke, lung cancer and heart disease are due to air pollution. This is having an equivalent effect to that of smoking tobacco, and much higher than, say, the effects of eating too much salt.”

As per WHO data, in terms of PM2.5, 14 Indian cities figured in the list of 20 most polluted cities in the world in 2016; in terms of PM10 levels, 13 cities in India were among the 20 most-polluted cities of the world in the same year. Air pollution in Delhi, the national capital, is now perennial and persists in the severe category. There seems to be no answer to this conundrum.

In addition, air pollution is a major contributor to climate change (global warming), which also affects health in different ways.

Global influenza pandemic

The world will face another influenza pandemic as predicted by the WHO. This occurs when a new influenza virus hits the world and affects people who are not immune to it. Flu is widespread in the US; so far there have been more than 20 million flu illnesses and more than 25,000 flu deaths since the season began in October last year (CDC).

India, particularly Rajasthan, Delhi, Gujarat is in the midst of its flu season; H1N1 (swine flu) is the predominant strain that is causing 70%-90% of seasonal flu infections. The National Centre for Disease Control has reported 14,803 confirmed H1N1cases across states till February 24, with 448 deaths.

Antimicrobial resistance

Easy over the counter availability of antibiotics and lack of awareness about correct usage of antibiotic drugs are among factors that have contributed to antibiotic resistance in the country. Also, the prevalence of multi-drug resistant infections is rising in the country. As per Global TB report 2017, estimated number of multi drug resistant (MDR) TB patients are 6,01,000 globally, of which 147000 (1/4th) are estimated from India. Treatment of MDR-TB or rifampicin-resistant-TB is prolonged and entails use of more expensive drugs.

Dengue

India is no stranger to Dengue and the disease is endemic in almost all states. Every year, mostly during monsoons, dengue affects thousands of people across the country. Dengue outbreaks in India have become more frequent, especially in the urban areas. Delhi is hyperendemic for dengue. What is of more concern is that it has spread to new regions, such as Orissa, Arunachal Pradesh and Mizoram, where dengue was historically non-existent (Emerg Microbes Infect. 2017 Aug; 6(8): e70).

Cricket World Cup anxiety

ICC Cricket World Cup 2019 is scheduled to be held in England in May this year. Cricket is not just a sport; it is a religion in India, where billions watch their team play, as one. It’s also a huge business now. And every match that India plays is likely to cause many anxious moments to the viewers.

Nipah

In May last year, Nipah virus disease was reported from in Kerala. The Government said that “this was not a major outbreak. It is only a local occurrence” (PIB). Nipah is a potentially life-threatening illness. It is an emerging zoonotic disease of public health importance. Will Nipah strike again?

Hearing aid from ear phone use

Constant exposure to loud noise can cause high frequency sensory neural hearing loss. Ear phone users are at risk of developing hearing loss and be candidates for hearing aids. This is especially true for young people who constantly use headphones and earphones for listening to high decibel music. Listening to music at 110-120 dB damages the hearing in less than an hour and a half.

An exposure of 90 dB (which is equivalent to the noise made by a power lawn mower or passing motorcycle) is allowed for 8 hours, 95 dB for 4 hours, 100 dB only for 2 hours, 105 dB ( power mower) for one hour and 130 dB for (live rock music) 20 minutes.

Ayushman Bharat

Around 14 lakh people have reportedly benefitted from Ayushman Bharat or Pradhan Mantri Jan Aryogya Yojana (PMJAY) scheme since it was launched in September 2018. And, the government has spent Rs 1800 cr for this.  The future of this scheme may depend on the parliamentary elections. If BJP returns to power, the scheme may emerge even bigger; but if it does not return to power, will Ayushman Bharat be repealed and replaced?

Digital illnesses

The constant of smartphones, tablets, and computers has spawned a whole new set of diseases. Terms like “text claw,” “Blackberry thumb,” “cellphone elbow”, “tech neck” are becoming common and represent medical conditions arising out of overuse of mobile phones. Fauxcellarm (“Phantom Ringing”), “Technoference” (digital interference in relationships) are few more such conditions.

Prolonged use of mobile phone can also cause neck pain, dry eyes, computer vision syndrome, and insomnia. About 60% of youth between 20 and 30 years of age fear losing their mobile phone, a condition called nomophobia ((“No-Mobile-Phobia”). Dependence on technology is adversely affecting our memory, attention span.

The World Health Organization (WHO) has now included video game addictions as “Internet Gaming Disorder” in its latest revision of the International Classification of Diseases (ICD-11). It described the addiction as a ‘pattern of persistent or recurrent gaming behavior’ that becomes so extensive it ‘takes precedence over other life interests’.

War

Recent events have placed India at the brink of war. A further escalation in hostilities is envisaged. But will there be a full-blown war? We hope not.

War causes tremendous destruction. Economy is negatively affected, infrastructure is damaged, there is scarcity of food and other resources, people lose their homes and become “refugees” in their own countries. Besides physical health, psychological trauma due to war has long-lasting effects.

Fake news

Fake news is a word in vogue today. It was also named word of the year in 2017. Fake news is deliberate misinformation and disinformation not only in the social media but also in the regular mainstream media. The intent is to mislead. There should be a law against fake news as it can generate social unrest in the community and polarize society into groups. Agitations may be an unwanted consequence of fake news.

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Past National President IMA

Dengue patients should defer blood donation for up to 6-12 months post-infection

Should screening for dengue be mandatory before blood transfusion?

I recently came across a story in The Muscat Daily (Jan. 23, 2019) which said “the Ministry of Health (MoH) and the Department of Blood Banks Services in Oman have announced on their Twitter accounts that “those affected by dengue virus will not be allowed to donate blood for six months”. Dengue cases are being reported in the country. The latest figures by the Ministry of Health revealed that until January 22, there were 52 recorded cases of dengue fever. In a statement, MoH said, “As a precautionary measure to prevent the spread of the infection, residents and citizens of the dengue-affected areas will also not be allowed to donate blood for 28 days.”  According to the Ministry, this is being put in place to help “prevent others from contracting the disease”.

Travel is a risk factor for spread of any infectious disease. With increasing travel, there is a chance of the disease appearing in another part of the country or the globe, where it did not occur previously. Consequently, the prevalence of dengue has increased several-folds across the world.

The dengue virus was recognized as a transfusion-transmitted pathogen in 2008 (World J Virol. 2015; 4(2):113-23). Chikungunya virus is also a transfusion-transmissible infection, as per the World Health Organization (WHO).

Since then, there has been concern about the risk of transmission of dengue via blood transfusion. Dengue virus becomes a blood-borne pathogen during the period of viremia, which coincides with the febrile period (World J Virol. 2015; 4(2):113-23).

 “In 2009, the American Association of Blood Banks placed dengue virus in the highest category of emerging infectious agents for their potential impact on transfusion recipient safety for the next years in North America” (World J Virol. 2015; 4(2):113-23).

Although rare, cases of transfusion-transmitted dengue fever have been reported. So far, five cases of transfusion-transmitted dengue, including one case of dengue hemorrhagic fever, have been formerly documented (World J Virol. 2015; 4(2):113-23).

Blood donors have been recognized as likely vehicles for transmission of the infection in endemic areas.

Dengue has become endemic in India, particularly in Delhi, where it has become a perennial infection.

In a study conducted to determine the prevalence of dengue virus infection in blood donors in a tertiary care centre, high seroprevalence (58%) of dengue infection in healthy asymptomatic blood donors was found; but, no active viremia was detected (J Clin Diagn Res. 2016;10(10): DC08–DC10). 

Seroprevalence is still a risk to blood safety and is a potential source for transfusion-transmitted infections.

NACO National Blood Transfusion Council “Guidelines for Blood donor selection and Blood Donor Referral 2017” recommend that blood donation should be deferred for 6 months following full recovery in case of history of dengue or Chikungunya. A person who has visited a Dengue and/or Chikungunya endemic area is deferred for 4 weeks following return from the endemic area if no febrile illness is noted.

In its 2012 “Guidelines on Assessing Donor Suitability for Blood Donation”, the WHO also recommends that individuals with a history of dengue or chikungunya virus in endemic areas should defer for 6 months following full recovery from infection. It further says that individuals who have visited an area endemic for dengue or chikungunya should defer for 28 days following return. And, those who have suffered a febrile illness during or following return from an endemic region should defer for 6 months following full recovery from infection

Dr NK Bhatia, Medical Director, Mission Jan Jagriti Blood Bank is a renowned name in blood banking with more than three decades of experience the field. According to Dr NK Bhatia, “Dengue patients are not allowed to donate blood for one year after treatment. If there is a history of blood/blood products transfusion, the same deferral period applies. This is also true for Chikungunya patients. Any person who has a ‘normal’ viral fever is not allowed to donate blood for 7 days after the active phase is over. Some extend this duration to one year.”

Hence, a medical history becomes very important when assessing eligibility of a prospective blood donor.

Always ask a history of dengue/Chikungunya, history of blood/blood product transfusion and history of any viral fever.

Dengue patients should defer blood donation for up to 6-12 months post-infection.

But, a question then arises “Should screening for dengue be mandatory before blood transfusion as is for hepatitis B virus, hepatitis C virus, HIV, syphilis, malaria” as many dengue patients go undetected in acute febrile illness?

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Past National President IMA

Revisiting dengue: Look for rise in hematocrit and not just falling platelets

Whenever dengue strikes, platelet counts along with shortage of platelets become the high point of discussion and panic sets in. Because it is presumed that platelet transfusion is the main treatment option for dengue. This is not so.

Platelet transfusions are not needed unless the platelet counts are less than 10,000 or there is active bleeding and thickening of blood.

Dengue causes low platelet count, but low platelet count by itself is never dangerous because patients with heart disease, diabetes are prescribed antiplatelets like aspirin, where they have a beneficial effect in preventing thrombotic complications. They are asked to report if they develop bleeding while on antiplatelets. Patients with idiopathic thrombocytopenic purpura (ITP) always have a low platelet count and they live a normal life on medication.

It’s not the platelet count alone with determines the prognosis of a patient of dengue.

More than the falling platelet count, it is the rapidity of fall in platelet count that is important. Even this does not alone is indicative of severity of illness.

Dengue not only causes low platelet count or destroys platelets, it also causes endothelial damage. Capillary leakage manifests as hemoconcentration and leads to increase in hematocrit and/or MCV and this is important. This is a medical emergency because a rising hematocrit means intravascular dehydration, which leads to multiorgan failure, hypotension and death.

Therefore, it is the rise in hematocrit along with rapid fall in platelets, which is the danger sign and is indicative of impending severe dengue.

Here is a simple Formula of 20 to identify high risk patients 

·         Rise in pulse by 20

·         Fall in upper blood pressure by more than 20

·         Rise in hematocrit by more than 20%

·         Rapid fall in platelets to less than 20,000

·         More than 20 hemorrhagic spots on the arm in one inch after tourniquet test

·         Difference between upper and lower BP is less than 20

Start fluid replacement at 20 ml/kg/hour immediately in such patients, and shift to nearest medical center for observation. 

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Immediate Past National President IMA

Predicting a dengue outbreak and practicing aparigrah

A global consortium of researchers has developed an early warning system to alert authorities on the Caribbean island of Barbados when a dengue outbreak is likely to strike. The study, published July 17, 2018 in the journal PLos Medicine, has shown that a period of drought, followed by intense rainfall 4 to 5 months later provides the optimum conditions for disease outbreak.

A dengue epidemic was most likely to occur five months after a drought. And, if rainfall follows the drought period, the chance of dengue outbreak increase. The researchers believe that after a drought people are more likely to leave water containers out. So, next time there is a period of intense rainfall, there are more places for water to collect and therefore more breeding grounds for mosquitoes.

According to the researchers, people tend to store water in containers during periods of drought, providing an ideal breeding ground for mosquitoes, which lay their eggs in pools of standing water.

Many parts of India too face drought-like conditions and people store water in several containers to meet their needs. And when the first rains come after periods of bright sunshine and scorching summers, some people like to keep containers or vessels outside to collect the first rainwater. 

Our roofs and verandahs or open spaces around the houses already are dumping grounds for old tyres, discarded drums, cans, utensils, etc. The mosquitoes, Aedes specifically, therefore have ample breeding sites.

India being a dengue-endemic country, these habits need to change. 

One must learn to keep only what is required and discard what is not.

Jainism calls this “aparigraha”, one of the five great vows (maha-vratas) of Jainism. “Parigraha” means possessiveness, grasping or greediness. The opposite of “parigrah” is “aparigraha” or non-possession or non-attachment, which means one should not keep anything more than what is necessary.

Aparigraha is also one of the five Yamas described in Patanjali Yoga Sutras. The others being ahimsa, satya, asteya and brahmacharya.

The first verse of Isha Upanishad says

ईशावास्यमिदं सर्वं यत्किञ्च जगत्यां जगत् । 

तेन त्यक्तेन भुञ्जीथा मा गृधः कस्यस्विद्धनम् ॥

īśāvāsyamidaṃ sarvaṃ yatkiñca jagatyāṃ jagat | 

tena tyaktena bhuñjīthā mā gṛdhaḥ kasyasviddhanam ||

‘Whatever there is changeful in this ephemeral world, all that must be enveloped by the Lord. By this renunciation, support yourself. Do not covet the wealth of anyone.’

Needs often become synonym with desires. Aparigraha helps us to separate the two.

It is customary to clean our houses for the festival of Diwali. This is also the time when we dispose of all the unwanted items lying in the house or give it away. A similar Diwali-like cleaning of houses can be customarily done before the onset of monsoons to remove or dispose of all the discarded old containers etc. in which water can collect and become breeding grounds for the mosquitoes.  

Dr KK Aggarwal

Padma Shri Awardee

Vice President CMAAO

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Immediate Past National President IMA