Neurologic Complications of Dengue

Dengue Research

There’s been a huge uptick in dengue research since climate change began to double the disease’s range and it started afflicting people in rich countries. Here’s a great database, from Harvard University, that will let you do your own research:

Dengue Occurrence World Wide
Dengue Occurrence World Wide

And here’s a fascinating development in the antigenic properties of the four dengue virus types:

“An international consortium of laboratories worldwide that are studying the differences among dengue viruses has shown that while the long-held view that there are four genetically-distinct types of the virus holds, far more important are the differences in their antigenic properties – the ‘coats’ that the viruses wear that help our immune systems identify them.

Dengue virus infects up to 390 million people each year. Around a quarter of these people will experience fever, headaches and joint pains, but approximately 500,000 people will experience potentially life-threatening complications, including haemorrhage and shock, where dangerously low blood pressure occurs. There are currently no vaccines against infection with dengue virus.

For decades, scientists have thought that there are four genetically-distinct types of the virus, known as serotypes, and that antigenic differences between the types play a key role in the severity of disease, its epidemiology and how the virus evolves – and hence these differences would be important in vaccine design.

When we become infected, our immune system sends out antibodies to try and identify the nature of the infection. If it is a pathogen – a virus or bacteria – that we have previously encountered, the antibodies will recognise the invader by antigens on its surface and set of a cascade of defences to prevent the infection taking hold. However, as pathogens evolve, they can change their antigens and disguise themselves against detection.

One of the unusual aspects of dengue is that in some cases when an individual becomes infected for a second time, rather than being immune to infection, the disease can be much more severe. One hypothesis to explain this is that the antibodies produced in response to infection with one strain of the virus somehow allow viruses of a different strain to enter undetected into cells, implying that antigenic differences between the serotypes are important.

Researchers from the Dengue Antigenic Cartography Consortium, writing in today’s edition of Science, analysed 47 strains of dengue virus with 148 samples taken from both humans and primates to see whether they indeed fit into four distinct types. The researchers found a significant amount of antigenic difference within each dengue serotype – in fact, the amount of difference within each serotype was of a similar order to that between the different types. This implies that an individual infected with one type may not be protected against antigenically different viruses of the same type, and that in some cases the individual may be protected against some antigenically similar strains of a different type.

Leah Katzelnick, a researcher from the Department of Zoology at the University of Cambridge, who began studying dengue after herself contracting the disease, says: “We were surprised at how much variation we saw…” Read more..

And here’s a useful discovery from a team at the University of Texas:

How dengue virus adapts as it travels

GALVESTON, Texas, July 6, 2015 – A researcher from The University of Texas Medical Branch at Galveston is an integral member of a collaborative group that is the first to explain the mechanisms that the Dengue virus has developed to optimize its ability to cause outbreaks as it travels across the globe to new places and revisits old ones. An early online version of this paper detailing the findings has recently been published in Science.

Dengue virus has been spreading throughout warm regions of the world, prompting the virus to adapt to new environments. This diversification in viral strains has resulted in the development of strains that appear associated with greater potential for sparking epidemics. Several dengue outbreaks have occurred when new dengue strains emerged and displaced the native strains that the local population had already developed immunity against. Until now, the mechanisms governing how and why some viral strains are better suited for causing widespread disease has been poorly understood.

The investigators examined the different clades of dengue virus-2 known to be circulating around Puerto Rico in 1994 when a severe epidemic broke out. Investigating the differences between the virus strain that was most commonly seen from 1986 to 1995 and a new, more potent viral strain that was first isolated in 1994 was the key to figuring out why this outbreak occurred.

They identified an interaction between the newcomer virus’s RNA and proteins within the host that allows the virus to bypass the host’s immune response, making it easier for the virus to invade. Based on the findings, the research team devised a model to explain the 1994 dengue outbreak in Puerto Rico.

“This study highlights the critical and oft forgotten role played by non-coding RNAs in the battle between viruses and their human hosts,” said author Mariano Garcia-Blanco, UTMB professor and chair of the department of biochemistry and molecular biology and also professor of emerging infectious diseases at the Duke-NUS Graduate Medical School in Singapore. “It emphasizes the importance of multidisciplinary research: a fabulous marriage of basic RNA biology and clinically informed epidemiology uncovered an unexpected route of virus evolution that explained (and perhaps could predict) epidemic potential.”

Other authors of this paper include Gayathri Manokaran, Esteban Finol, Jayantha Gunaratne, Eugenia Z. Ong, Hwee Cheng Tan, October M. Sessions, Alex M. Ward, Duane J. Gubler and corresponding author Eng Eong Ooi from the Duke-NUS Graduate Medical School; Chunling Wang, and Eva Harris from the University of California, Berkeley and Justin Bahl from the University of Texas School of Public Health, Houston.

This research was supported by the Singapore National Medical Research Council, the Ministry of Health in Singapore, Institute of Molecular and Cell Biology, Agency of Science, Technology and Research in Singapore and the U.S. National Institutes of Health.

Here are some links to dengue research in PLOS1:

Here are more dengue research links from Travel Medicine:

Cited in Scopus: 0
Burke A. Cunha, Sigridh Munoz-Gomez
Travel Medicine and Infectious DiseaseVol. 12Issue 3p293–295
Published online: April 3, 2014
Cited in Scopus: 7
Danilo Tomasello, Patricia Schlagenhauf
Travel Medicine and Infectious DiseaseVol. 11Issue 5p274–284
Published online: August 19, 2013
Cited in Scopus: 1
 Karin Leder, Margot Mutsch, Patricia Schlagenhauf, Christine Luxemburger, Joseph Torresi
Travel Medicine and Infectious DiseaseVol. 11Issue 4p210–213
Published online: July 25, 2013
Cited in Scopus: 0
 Natalie Cleton, Chantal Reusken, Jean-Luc Murk, Menno de Jong, Johan Reimerink, Annemiek van der Eijk, Marion Koopmans
Travel Medicine and Infectious DiseaseVol. 12Issue 2p159–166
Published online: December 2, 2013
Cited in Scopus: 2
 Praveen Nilendra Weeratunga, Manjula Chandragomi Caldera, Inuka Kishara Gooneratne, Ranjanie Gamage, Priyankara Perera
Travel Medicine and Infectious DiseaseVol. 12Issue 2p189–193
Published online: December 12, 2013
Cited in Scopus: 4
 Yasutaka Mizuno, Yasuyuki Kato, Shigeyuki Kano, Tomohiko Takasaki
Travel Medicine and Infectious DiseaseVol. 10Issue 2p86–91
Published online: March 19, 2012
Cited in Scopus: 0
 Aravinthan Varatharaj
Travel Medicine and Infectious DiseaseVol. 12Issue 2p194
Published online: January 31, 2014
Cited in Scopus: 0
 Beuy Joob, Viroj Wiwanitkit
Travel Medicine and Infectious DiseaseVol. 12Issue 2p195
Published online: March 13, 2014
Cited in Scopus: 0
 Viroj Wiwanitkit
Travel Medicine and Infectious DiseaseVol. 11Issue 5p332
Published online: September 10, 2013
Cited in Scopus: 1
 Sadegh Chinikar, Seyed Mojtaba Ghiasi, Nariman Shah-Hosseini, Ehsan Mostafavi, Maryam Moradi, Sahar Khakifirouz, Fereshteh Sadat Rasi Varai, Mahboubeh Rafigh, and others
Travel Medicine and Infectious DiseaseVol. 11Issue 3p166–169
Published online: November 28, 2012
Cited in Scopus: 0
 Marion Delord, Cristina Socolovschi, Philippe Parola
Travel Medicine and Infectious DiseaseVol. 12Issue 5p443–458
Published online: September 14, 2014
Cited in Scopus: 1
 Siu-keung Edmond Ma, Wang Christine Wong, Chi-wah Ryan Leung, Sik-to Thomas Lai, Yee-chi Janice Lo, Kai-hay Howard Wong, Man-chung Chan, Tak-lun Que, and others
Travel Medicine and Infectious DiseaseVol. 9Issue 3p95–105
Published online: June 14, 2010
Cited in Scopus: 1
 Jason M. Blaylock, Ashley Maranich, Kristen Bauer, Nancy Nyakoe, John Waitumbi, Luis J. Martinez, Julia Lynch
Travel Medicine and Infectious DiseaseVol. 9Issue 5p246–248
Published online: July 21, 2011
Cited in Scopus: 11
 David W. Smith, David J. Speers, John S. Mackenzie
Travel Medicine and Infectious DiseaseVol. 9Issue 3p113–125
Published online: June 14, 2010
Cited in Scopus: 2
 Uzma N. Sarwar, Sandra Sitar, Julie E. Ledgerwood
Travel Medicine and Infectious DiseaseVol. 9Issue 3p126–134
Published online: June 28, 2010
Cited in Scopus: 1
 Andreas Neumayr, Christoph Hatz, Johannes Blum
Travel Medicine and Infectious DiseaseVol. 11Issue 6p337–349
Published online: October 31, 2013
Cited in Scopus: 2
 Burke A. Cunha, Arthur Gran, Sigridh Munoz-Gomez
Travel Medicine and Infectious DiseaseVol. 11Issue 1p66–69
Published online: October 22, 2012
Cited in Scopus: 5
 Eleonora Lupi, Christoph Hatz, Patricia Schlagenhauf
Travel Medicine and Infectious DiseaseVol. 11Issue 6p374–411
Published online: November 6, 2013
Cited in Scopus: 2
 Mary Elizabeth Wilson, Lin H. Chen
Travel Medicine and Infectious DiseaseVol. 12Issue 3p205–207
Published online: April 17, 2014
Cited in Scopus: 1
 Kelly Kamimura-Nishimura, Donald Rudikoff, Murli Purswani, Stefan Hagmann
Travel Medicine and Infectious DiseaseVol. 11Issue 6p350–356
Published online: October 28, 2013

Dengue Shock Syndrome

What is Dengue Shock Syndrome?

Dengue Shock Syndrome is a collection of symptoms resulting from a dengue infection. Its symptoms – including hemorrhaging – resemble those you’d see after an accident, when someone is ‘in shock’. Typically, older children or adults suffer 2–7 days of high fever and show two or more of the following symptoms:

  • severe headache,
  • retro-orbital eye pain,
  • myalgias,
  • arthralgias,
  • a diffuse erythematous maculo-papular rash, and
  • mild hemorrhagic manifestation.
  • Subtle, minor epithelial hemorrhage, in the form of petechiae, are often found on the lower extremities (but may occur on buccal mucosa, hard and soft palates and or subconjunctivae as well), easy bruising on the skin, or the patient may have a positive tourniquet test.
  • Other forms of hemorrhage such as epistaxis, gingival bleeding, gastrointestinal bleeding, or urogenital bleeding can also occur, but are rare.
  • Leukopenia is frequently found and may be accompanied by varying degrees of thrombocytopenia.
  • Children may also present with nausea and vomiting.
  • Patients with DF do not develop substantial plasma leak (hallmark of DHF and DSS, see below) or extensive clinical hemorrhage.
Dengue virus image
Dengue virus: Dengue Shock Syndrome

Serological testing for anti-dengue IgM antibodies or molecular testing for dengue viral RNA or viral isolation can confirm the diagnosis, but these tests often provide only retrospective confirmation, as lab results are typically not available until well after the patient has recovered.

Clinical presentation of DF and the early phase of DHF are similar, and therefore it can be difficult to differentiate between the two forms early in the course of illness. With close monitoring of key indicators, the development of DHF can be detected at the time of defervescence so that early and appropriate therapy can be initiated.

The key to successfully managing patients with dengue infection and lowering the probability of medical complications or death due to DHF or DSS is early recognition and anticipatory treatment(For more detailed guidance on management for DF please see the recommended treatment courses for DHF in the links listed below.)

Dengue Hemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS): The third clinical presentation results in the development of DHF, which in some patients progresses to DSS. Vigilant is critical for identifying warning signs of progressing illness and early symptoms of DHF which are very similar to those of DF. Case Definitions Page

There are three phases of DHF:

  1. the Febrile Phase;
  2. the Critical (Plasma Leak) Phase; and
  3. the Convalescent (Reabsorption) Phase.

The Febrile Phase: Early in the course of illness, patients with DHF can present much like DF, but they may also have hepatomegaly without jaundice (later in the Febrile Phase). The hemorrhagic manifestations that occur in the early course of DHF most frequently consist of mild hemorrhagic manifestations as in DF. Less commonly, epistaxis, bleeding of the gums, or frank gastrointestinal bleeding occur while the patient is still febrile (gastrointestinal bleeding may commence at this point, but commonly does not become apparent until a melenic stool is passed much later in the course). Dengue viremia is typically highest in the first three to four days after onset of fever but then falls quickly to undetectable levels over the next few days. The level of viremia and fever usually follow each other closely, and anti-dengue IgM anti-bodies increase as fever abates.

The Critical (Plasma Leak) Phase: About the time when the fever abates, the patient enters a period of highest risk for developing the severe manifestations of plasma leak and hemorrhage. At this time, it is vital to watch for evidence of hemorrhage and plasma leak into the pleural and abdominal cavities and to implement appropriate therapies replacing intravascular losses and stabilizing effective volume. If left untreated, this can lead to intravascular volume depletion and cardiovascular compromise. Evidence of plasma leak includes sudden increase in hematocrit (≥20% increase from baseline), presence of ascites, a new pleural effusion on lateral decubitus chest x-ray, or low serum albumin or protein for age and sex. Patients with plasma leak should be monitored for early changes in hemodynamic parameters consistent with compensated shock such as increased heart rate (tachycardia) for age especially in the absence of fever, weak and thready pulse, cool extremities, narrowing pulse pressure (systolic blood pressure minus diastolic blood pressure <20 mmHg), delayed capillary refill (>2 seconds), and decrease in urination (i.e., oliguria). Patients exhibiting signs of increasing intravascular depletion, impending or frank shock, or severe hemorrhage should be admitted to an appropriate level intensive care unit for monitoring and intravascular volume replacement. Once a patient experiences frank shock he or she will be categorized as having DSS. Prolonged shock is the main factor associated with complications that can lead to death including massive gastrointestinal hemorrhage. Interestingly, many patients with DHF/DSS remain alert and lucid throughout the course of the illness, even at the tipping point of profound shock. CDC:

Doctors: See case definition for DHF and DSS. Adobe PDF fileExternal Web Site IconThere are no good videos about dengue shock syndrome, but this text video might help:

India’s Botanical Dengue Drug

India’s botanical Dengue drug is getting world wide attention. At last! India, the home of ayurvedic medicine, has begun work to develop, test and market a botanical drug to treat of dengue, with drug major Sun Pharma announcing its collaborative effort with the International Centre for Genetic Engineering and Biotechnology (ICGEB).
The move follows a March announcement of success in the drug’s initial development stage through a joint project between the ICGEB, the Department of Biotechnology (DBT).

Dengue Mosquito: Aedes Aegypti
Dengue Mosquito: Aedes Aegypti

Sun Pharma will fund entire development programme of Cissampelos pariera (Cipa), the botanical drug to treat all strains of dengue. While the pharma giant will pay royalty following commercialisation of the drug, the ICGEB will provide the technical know-how and pre-clinical expertise.
“Using the knowledge of traditional Indian medicine, we explored the indigenous herbal bio-resource to identify plants with pan-DENV inhibitory activity and identified CIPA as a safe, affordable and effective solution,” said Dr Dinakar M Salunke, director, ICGEB, New Delhi.
Given the densely-populated cities and the high prevalence of the mosquito that spreads dengue — aedes aegypti — India is home to close to 50% of the global population estimated to be at risk of dengue. Severe dengue, which can potentially kill, correlates with very high-virus load, reduction in platelet counts and haemorrhage.
The new drug is expected to reduce high-virus load and make the disease milder, leading to fewer hospitalisations. The collaboration aims to explore how the extract prepared from Cipa Linn can inhibit the replication of virus in living cells against dengue infection.
The terms of this agreement permits Sun Pharma’s access to all the intellectual properties of this drug cross 17 countries.
“In tropical countries like India, where dengue outbreaks are significantly intense, a drug for dengue is an unmet public health need. Our partnership with ICGEB aims to develop Cipa as a safe, effective & affordable botanical drug for treatment of dengue,” said Kirti Ganorkar, senior V-P, business development and portfolio management, Sun Pharma, the world’s fifth largest generic pharmaceutical company.
The ICGEB will establish assay systems for development of Cipa for treatment of dengue infection for a pre-defined period of time. The ICGEB will work exclusively with Sun Pharma for the development of this drug, and clinical treatment strategies based on botanical and phyto-pharmaceuticals. Sun Pharma will pay royalties on sales post commercialisation. Other financial details of this agreement are confidential.
Dengue is estimated to costs India over $1.1 billion (about Rs 7,260 crore) annually, with the cost of medical care being nearly $550 million and the indirect cost, in terms of lost wages, being another $550 million. Read more..

Dengue Virus Structure

What’s the Dengue virus look like? What’s its structure? An imaging technique called neutron scattering is giving us an intimate look at the dengue virus structure, as this article from Oak Ridge National Laboratory makes clear:

Dengue Virus Structure
Dengue Virus Structure

Without a host, a virus is a dormant package of proteins, genetic material and occasional lipids. Once inside a living cell, however, a virus can latch onto cell parts and spring into action—mutating, replicating and spreading into new cells.

The mosquito-borne Sindbis virus is a member of the same family that causes West Nile fever and dengue fever.
The mosquito-borne Sindbis virus is a member of the same family that causes West Nile fever and dengue fever. [Image credit: Paredes et al., Virology 324, 373 (2004)]

“There’s this thought that a virus has one structure, whether it’s in a mosquito or in a human cell,” says ORNL researcher Flora Meilleur. “But a mosquito cell and a human cell are very different, which means that a virus may have to reorganize itself.”

Meilleur is part of a research team from ORNL and North Carolina State University (NCSU) that is examining how viruses change their structure when they move among different host species. Understanding how a virus reorganizes itself when migrating from a mosquito to a human is essential for developing medicines that can block the spread of viruses.

The team’s most recent study, published in the Journal of Virology, focuses on the Sindbis virus, a member of the arbovirus family that causes infectious diseases like yellow fever, dengue fever and West Nile fever. Scientists have previously observed host-specific differences in the Sindbis virus, but Meilleur says the team’s study is the first time that subtle structural variations in Sindbis have been observed and characterized. “This is the first structural comparison of Sindbis viruses grown in different host cells.”

The team, which includes Meilleur, Lilin He, Dean Myles and William Heller from ORNL and Amanda Piper, Raquel Hernandez and Dennis Brown from NCSU, used a technique called small-angle neutron scattering to compare virus particles from mammalian and insect cells. Their results revealed that the mammalian-grown viruses exhibited distinct features, including a larger diameter, increased levels of cholesterol and a different distribution of genetic material in the virus core. “The results suggest that structural changes are likely to be important in transmission between hosts,” Meilleur says. “The chemical environment of the host cell appears to affect how the virus assembles itself.”

The team’s structural studies were performed at ORNL’s High Flux Isotope Reactor using the facility’s Bio-SANS instrument, which uses chilled neutrons to analyze the structure, function and dynamics of complex biological systems. Whereas techniques like X-ray scattering can cause radiation damage in biological samples during analysis, neutron scattering is nondestructive. “Neutron scattering enables us to see differences in the composition of the virus without destroying the sample,” Meilleur says. The ability of neutrons to see the composition of biological materials is linked to the particles’ sensitivity to hydrogen, which is a key component in compounds like proteins and cell membranes.

Although viral agents from the arbovirus family are a major source of human disease across the globe, very few effective vaccines exist for their control. A detailed understanding of the mechanism by which viruses gain entry into cells will be crucial for the successful pursuit of pharmaceuticals to ultimately treat and prevent infection from members of this virus family.

This just in: Scientists at UMass Medical School have performed the first CRISPR/Cas9 screen to discover human proteins that Zika virus needs for replication. This work, led by Abraham Brass, MD, PhD, assistant professor in microbiology & physiological systems, reveals new leads that may be useful for halting Zika, dengue and other emerging viral infections. The study appears online in the journal Cell Reports.

“These genetic screens give us our first look at what these viruses need to survive,” said Dr. Brass. “Our lab and others in our field have worked hard to develop the systems and infrastructure needed to investigate the genetics underlying how viral pathogens use our own cell’s machinery to replicate. This has allowed the scientific community to respond quickly when the Zika virus threat emerged. In our lab, we adapted the technology and tools we’d established over the last four years working with other viruses to begin investigating the biology of Zika virus.”

Dengue Zika Larvicides

Are Dengue, Zika and GM Mosquitoes Connected by a larvicide?

Could it be that Dengue, Zika and Larvicides are connected? Dengue, and outbreak of Zica, and GM mosquitoes are being discussed in the same breath. The Zica disease is similar to dengue, and the two have long cohabited, but Zica has never afflicted as many people as seriously as it is doing in Brazil. The fact that the range for zica’s vectors overlaps the aedes aegypti range – and  that there’s a GM mosquito test going on within that vast territory – suggest that the presence of the GM mosquitos and the outbreak of zica are probably coincidental. Especially since the date of release of the GM insects is given as 2015 – hardly sufficient time to breed and spread zica so far.

Zica Map
Zica Map

There’s always a chance that an Oxitec mosquito is to blame, but here’s a persuasive article suggesting that a chemical is to blame and Zica is not the culprit:

Argentine and Brazilian doctors name larvicide as potential cause of microcephaly:

report from the Argentine doctors’ organisation, Physicians in the Crop-Sprayed Towns,[1] challenges the theory that the Zika virus epidemic in Brazil is the cause of the increase in the birth defect microcephaly among newborns.   The increase in this birth defect, in which the baby is born with an abnormally small head and often has brain damage, was quickly linked to the Zika virus by the Brazilian Ministry of Health.

However, according to the Physicians in the Crop-Sprayed Towns, the Ministry failed to recognise that in the area where most sick people live, a chemical larvicide that produces malformations in mosquitoes was introduced into the drinking water supply in 2014. This poison, Pyriproxyfen, is used in a State-controlled programme aimed at eradicating disease-carrying mosquitoes.  The Physicians added that the Pyriproxyfen is manufactured by Sumitomo Chemical, a Japanese “strategic partner” of Monsanto.

Pyriproxyfen is a growth inhibitor of mosquito larvae, which alters the development process from larva to pupa to adult, thus generating malformations in developing mosquitoes and killing or disabling them. It acts as an insect juvenile hormone or juvenoid, and has the effect of inhibiting the development of adult insect characteristics (for example, wings and mature external genitalia) and reproductive development. It is an endocrine disruptor and is teratogenic (causes birth defects), according to the Physicians.The Physicians commented: “Malformations detected in thousands of children from pregnant women living in areas where the Brazilian state added Pyriproxyfen to drinking water are not a coincidence, even though the Ministry of Health places a direct blame on the Zika virus for this damage.” Read more here….

Fighting Zika – Not The Virus Itself – Might Have Caused Birth Defects

June 26, 2016

The media said that the mosquito borne Zika virus is likely causing microcephaly as well as dozens of other illnesses. They also claimed that insecticides were not related to the development disorder. They seem to have been wrong on both cases.

Since December 2015 U.S. media ran a panic campaign round the Zika virus. That virus was said to cause many bad things including microcephaly, a development distortion of the head  of unborn babies, if the mother was infected with Zika during pregnancy.

After looking into the issue and the available data I concluded that: The Zika Virus Is Harmless:

The virus is long known, harmless and the main current scare, that the virus damages unborn children, is based on uncorroborated and likely false information.

There is absolutely no sane reason for the scary headlines and the panic they cause.The virus is harmless. It is possible, but seems for now very unlikely, that it affects some unborn children. There is absolutely no reason to be concerned about it.

As this is all well known or easy to find out why do the media create this sensation?

By March the media attributed all known human ills to Zika though every headline doing so included a telltale caveat may. I mocked these in Reading About Zika May Hurt Your Brain

[E]ven while Zika is known to be less harmful than an average flue, one headline after the other tries to create the impression that it is some really awful, new bug that may be responsible for about any ailment. That it may spread like wildfire and may have other terrible consequences. May, as in ‘the sky may fall’, is indeed the most operative word here.

There followed a collection of 35 recent “Zika may cause …” headlines.

Meanwhile doctors in the Zika affected areas in Brazil pointed out that the real cause of somewhat increased microcephaly in the region was probably the insecticide pyriproxyfen, used to kill mosquito larvae in drinking water:

The Brazilian doctors noted that the areas of northeast Brazil that had witnessed the greatest number of microcephaly cases match with areas where pyriproxyfen is added to drinking water in an effort to combat Zika-carrying mosquitoes. Pyriproxyfen is reported to cause malformations in mosquito larvae, and has been added to drinking water in the region for the past 18 months.

Pyriproxyfen is produced by a Sumitomo Chemical – an important Japanese poison giant. It was therefore unsurprising that the New York Times and others called the doctors report a “conspiracy theory” and trotted out some “experts” to debunk it.

But facts are facts and as these come to the fore the embarrassed media will now likely stay silent.

The New England Complex Systems Institute in Cambridge just published a new study that falsifies the assumed link between Zika and microcephaly. Science Daily reports:

In Brazil, the microcephaly rate soared with more than 1,500 confirmed cases. But in Colombia, a recent study of nearly 12,000 pregnant women infected with Zika found zero microcephaly cases. If Zika is to blame for microcephaly, where are the missing cases? Perhaps there is another reason for the epidemic in Brazil.

Well, maybe those doctors on the ground in Brazil knew what they were talking about. The scientist at the New England Complex Systems Institute also researched the pyriproxyfen thesis. They found.. Read more..

Then there’s this article from Bloomberg:

Genetically modified mosquitoes that would help fight the Zika virus are getting urgent attention from U.S. regulators as global health officials raise alarms about the pathogen’s spread. The U.S. Food and Drug Administration is in the final stages of reviewing an application from Intrexon Corp.’s Oxitec unit to conduct a field trial in the Florida Keys, Oxitec Chief Executive Officer Hadyn Parry said in a phone interview. Parry wasn’t able to provide further details on the timing of an FDA decision.
Oxitec genetically modifies the males in a breed of mosquito known as Aedes aegypti — responsible for transmitting Zika, Dengue, Chikungunya and Yellow Fever — so that their offspring die young. The Zika virus has been spreading “explosively” in South and Central America, the World Health Organization said Thursday. Developing a vaccine could take years, drugmakers and health experts have cautioned.

Here’s the background: Oxitec, an American-owned British company, has been working to develop a genetically modified mosquito in hopes of controlling dengue outbreaks on a broad scale. They breed and release millions of modified insects in populated areas where dengue is endemic. The story below,

 

In 2015 Oxitec proudly announced  that the mosquitos they’d genetically modified – which they call ‘friendly Aedes aegypti’ – had decimated the local mosquito population in a field trial in Juazeiro, Brazil by 95%. New dengue cases were way below the modelled threshold for epidemic disease transmission.

Dengue Zika juazeiro map
Dengue Zika juazeiro map

Here’s a map showing where the deformed babies are being born:

dengue zika brazil
dengue zika brazil

Zika was first confirmed in Brazil in May, 2015, but had been seen in other nations before. But Zika in Brazil does not seem to behave like the Zika they were familiar with.

Questions

  1. Why didn’t zika cause an epidemic of birth defects in any other country?
  2. How would you miss a tenfold increase in children born with most of their brain missing?
  3. Could the Zika epidemic be linked to genetically modified mosquitoes?

Oxitec released a strain of male mosquitoes in Juazeiro which create larvae that normally die in the absence of antibiotics. This is supposed to help decimate wild mosquito populations when these males are released in the wild. But Oxitec estimates 3-4% of the larvae survive to adulthood in the absence of the tetracycline antibiotic. These larvae should then be free to go on and reproduce and pass on their genes. In fact, they may be the only ones that are passing on their genes in places that have their wild mosquito population decimated by these experiments. Here are some questions whose answers we’ll post as they come in:

What is the effect on these mosquitoes that grow up with a mutilated genome?

Will the genetic modification introduce a fitness cost?

Should they have greater difficulty surviving?

What do we know about Oxitec’s mosquitoes?

Has sufficient research been done on how a genetically mutilated mosquito copes with viral infections?

Could Oxitec’s mosquito be more susceptible to certain pathogens?

Could it pass those pathogens onto humans?

Stay tuned. In the meantime, here’s the Malaysian Government’s Biosafety assessment of the Oxitec experiment. And here’s news of the first Zica lab test, developed in Germany.

Dengue in the USA

Dengue in the USA

Dengue in the USA is here to stay. With the Department of Health of Hawaii confirming two locally-acquired dengue fever cases in the state, two video bloggers have decided to share their own struggles dealing with the tropical disease to help raise public awareness.

Hawaii State health officials are investigating a dengue fever cluster. Thirty-three people on Hawaii’s Big Island have become sick with dengue since September – the first locally transmitted outbreak of the viral illness on the Big Island and the first outbreak in the state since five people were infected on Oahu in 2011. Twenty-five of those infected in this current outbreak are residents of the Big Island, while eight are visitors. Four children are among those who have become ill. All patients have recovered or are recovering.

Allie Wesenberg and Charles Trippy feature prominently on an ongoing web series known as “Internet Killed Television” on the YouTube channel CTFxC.

For the past seven years, the channel, which caters to more than 1.5 million subscribers, has been uploading adventure clips of the duo taken in different parts of the world.

On one of their recent trips dated on Oct.13, Wesenberg and Trippy visited several popular spots in Hawaii, including South Kona’s Honaunau, the Volcanoes National Park and South Point.

However, by the time they got back from their Big Island trip, Wesenberg suddenly fell ill and was taken to the hospital on Oct. 22. Yep, dengue in the USA is a reality. Now watch the video:

Natural Dengue Controls

Many states are using natural dengue controls to fight dengue, as this article explains:

Guangzhou Turns to Mosquito-Eating Fish to Help Control Dengue Outbreak

The southern Chinese city of Guangzhou has introduced a fish that eats mosquito larvae, in an effort to control its worst-ever dengue fever outbreak, state news media have reported.

Mosquito fish, seen here in an aquarium in Virginia, are being deployed in the southern Chinese city of Guangzhou to help fight dengue fever.
Mosquito fish, seen here in an aquarium in Virginia, are being deployed in the southern Chinese city of Guangzhou to help fight dengue fever.Credit Associated PressSome scientists have warned that use of the nonnative mosquito fish could have unexpected consequences, while others say that mosquito fish are already found in Guangdong waters and the environmental impact might not be significant, but that the effectiveness of the fish may also be limited.

Some scientists have warned that use of the nonnative mosquito fish could have unexpected consequences, while others say that mosquito fish are already found in Guangdong waters and the environmental impact might not be significant, but that the effectiveness of the fish may also be limited. As of Monday, the number of dengue cases in Guangdong Province this year had reached 41,155, the local health authorities reported, with six deaths. The province has seen 200 to 300 new cases a day in recent days. That is lower than the more than 400 per day last week and the more than 1,000 per day the week before that, offering some hope that the outbreak is beginning to ease…. Read more.

 

Natural Dengue Strategies

Here are some natural tricks that discourage aedes aegypti mosquitoes:

  • Eat raw garlic, cook with onion and bell pepper, and take vitamin B. All these foods help produce a body odor that mosquitoes find unattractive.
  • Grow mint, roses, tuberose (Polianthes tuberosa), orchid tree (Aglaia odorata var. microphylla), and marigold. All repel mosquitoes to some degree.
  • Burn the leaves of the lemon-scented gum eucalyptus (Eucalyptus citriodora Hook) for household protection.
  • Use outdoor LED lights on your porch and around your house. They don’t attract pests like other lights.
  • Burn citronella candles outside.

Natural (Mostly) Insecticides & Repellents

If natural options are not available to everyone mosquito sprays can be a good alternative. Some of the least toxic sprays:

  • Oil of Lemon Eucalyptus has been used for many years in China as a mosquito repellent.
  • Essential Oils – Some essential oils used in repellents include Cedarwood, Soybean Oil (www.biteblocker.com), and Geraniol (MosquitoGuard- www.wildroots.com, Bite Stop- www.bitestop.com, Bugband- www.bugband.net).
  • Picaridin – a synthetic dervived from pepper. The CDC says its protection is comparable to DEET at similar concentrations (Cutter Advanced).
  • Citronella – The active ingredient in those candles. It’s in some natural spray blends like Insect Shield (Bug Off) Synergy: an undiluted, therapeutic grade blend of the essential oils of Citronella, Eucalyptus, Cedarwood, Lemongrass, Lavender, Litsea, Tea Tree, Patchouli & Catnip.
  • Vanillin – Adding vanillin 5% to plant-based repellents and to DEET repellents increased their protection by about 2 hours. [Read this]

Some Commercial Products

All these repellents have different durations of effectiveness so be sure to reapply them following the directions on the label to repel mosquitoes most effectively.

Product Name & Link: Cutter Lemon Eucalyptus Insect Repellent Pump Spray, 4-Ounce.

Sales Pitch: Cutter lemon eucalyptus pump spray is an effective, naturally plant to based repellent that repels mosquitoes for up to 6 hours. Contains oil of lemon eucalyptus to the only plant to based ingredient recommended by the centers for disease control and prevention (CDC). Average Score: 4.2/5

Product Name & Link: Bite Blocker Organic Insect Repellent Spray, 6 Oz.

Sales Pitch: Bite Blocker’s proven effective Insect Repellent now in a highly effective waterproof formulation though enough for extreme environments and safe for the entire family. This Xtreme botanical formula provides protection form bites for up to 8 hours against mosquitoes, blackflies and more than 2 hours for ticks. Average Score: 4.1/5.0

Dengue in Asia

Dengue Fever Outbreaks Strike in Asia:

The number of dengue fever cases in Taiwan in the past four months has jumped to more than 4,000, recording the worst summer outbreak in the country since it started keeping systematic track of the disease in 2003, the Centers for Disease Control (CDC) said Thursday. As of Wednesday, the total number of dengue cases reported around the country since May 1 had reached 4,343, compared with 3,704 in the same period of last year, the CDC said. “The situation might ease up after September if we could effectively get things under control,” said CDC Deputy director-general Chuang Jen-hsiang. More

Southern China, Japan, Taiwan Battle Potentially Deadly Disease

Though much of the world is focused on the Ebola virus, pockets of Asia are struggling with record outbreaks of a mosquito-borne infectious disease called dengue fever, which has no specific drug treatment. Read more…

Dengue deaths nearly triple in Malaysia

KUALA LUMPUR – Prime Minister Najib Razak on Tuesday urged people to take precautions against dengue fever, which has caused 44 deaths in the first five weeks of the year in Malaysia. “Dengue is now a growing concern in several areas around Malaysia,” he said. “I hope you will take precautions as well and immediately seek medical help if you experience symptoms of dengue.” Najib said the government was intensifying its efforts to deal with the mosquito-borne disease, including sanitation awareness campaigns and taking actions against contractors who neglect to clean up their work sites. Health Ministry director general Noor Hisham bin Abdullah said 44 people died from dengue from Jan 1 to Feb 7, compared with 17 deaths during the same period last year. A total of 15,039 cases of dengue fever were reported nationwide during the first five weeks of 2015, compared with the 9,453 last year. More

Dengue and the W.H.O.

Dengue and the WHO are clashing!

MANILA, Philippines – With almost half of the world’s population now at risk of dengue, the World Health Organization (WHO) is pushing for “cross-border” collaboration to stop the spread of the mosquito-borne disease.

The WHO said collaboration to build regional capacity is the key to avert the impact of the dengue outbreak that has affected more than 100 countries worldwide. “Through such cross-border collaboration and sharing of dengue information, timely sensing of the dengue situation can improve preparedness within each country in the event of an outbreak,” the WHO said. The agency said the incidence of dengue has been increasing dramatically in the last few decades, with an estimated 50-100 million dengue infections occurring worldwide each year.

Before 1970, only nine countries had experienced severe dengue epidemics, but today the disease is endemic in more than 100 countries. “Not only is the number of cases increasing as the disease spreads to new areas, but frequent explosive outbreaks are occurring,” the WHO said.

It said the Western Pacific, home to a quarter of the world’s population, bears the heavy socio-economic burden due to dengue. In 2013, member-states of the Western Pacific region reported 428,635 cases and 964 deaths from the disease. The Philippines recorded over 204,906 cases and 660 deaths last year. The WHO recently held the 10-day Fourth Asia-Pacific Dengue Workshop to discuss measures to lessen the dengue epidemic.

It said there is currently no available vaccine or effective medication against dengue, thus preventing mosquitoes from breeding and propagating and protecting people from Aedes mosquito vectors are the best defense against the disease. Early detection of suspected cases, access to proper medical care and disease management, especially during outbreaks, can help in reducing the number of fatal cases, the WHO noted.

The WHO supports countries through its collaborating network of centers and laboratories, and provides technical and financial support and guidance for the effective management of dengue. WHO regional director for Western Pacific Shin Young-soo said dealing with a deadly disease such as dengue requires strong and consistent collaboration from everyone.

“Dengue hinders progress, which prevents our people from enjoying quality life. It is therefore imperative that we pool our considerable resources together to rid our region of dengue,” he said. He then urged governments, communities, stakeholders and donor agencies to strengthen efforts and programs for the routine control of vector-borne diseases and to ensure that systems are in place to detect, prepare for and respond to dengue outbreaks.

Read more about dengue in the Philippine Star