Was there Dengue bribery in Philippines? Questions hover over Asia’s first dengue vaccination program in Philippines.
The Aedes aegypti mosquito carries the dengue virus, Zika virus, and other mosquito-borne illnesses as it travels from person to person.
Asia’s first dengue vaccine has been distributed in a mass school-based immunization program in the Philippines. So far, the program appears to be running without difficulties, but some health professionals are concerned that the vaccine was released before researchers could ensure its long-term safety.
From the beginning, the vaccine’s French manufacturer Sanofi Pasteur has been concerned about a potential problem with the vaccine — that while it could help prevent dengue initially, it could later increase the severity of the disease, according to Dr. Antonio Dans, a professor at the University of the Philippines College of Medicine.
“The real dengue we are afraid of is severe dengue, not the mild ones,” Dans said in a statement. “If a vaccine prevents mild disease but causes severe dengue, we shouldn’t be using it at all.”
This possibility is being monitored by the vaccine’s developer, Dans said in a news release; and since the phenomenon may happen a full three years after immunization occurs, it will take some time to study the vaccine’s long term effects.
However, as the virus infects as many as 400 million people annually, the vaccine for dengue has been awaited with increasing impatience. In an effort to stem the spread of the virus in regions heavily burdened by the disease, the WHO recommended that the drug be introduced in dengue-endemic sites while awaiting prequalification.
According to the organization, the WHO is now waiting on an application from the vaccine’s manufacturer.
The vaccine, Dengvaxia, has also been registered in Mexico, Brazil and El Salvador. Now, the Philippines — which in 2015 saw an almost 60 percent increase in dengue cases from the year prior — has become the first to make the vaccine commercially available.
“This initiative sends a strong message to the rest of the … world that dengue vaccination is a critical addition to integrated disease prevention efforts,” according to a statement from the vaccine’s developer Sanofi Pasteur.
The official launch of the school-based immunization program on April 4 sidestepped a prequalification procedure by the WHO, as is standard for new vaccines to ensure safety and effectiveness. This raised additional concern from some medical professionals, according to Philippine media network GMA, who say the immunization program should not have skipped the prequalification process, especially considering such limited knowledge of the vaccine’s long-term side effects.
Still, the company said the Dengvaxia vaccine, which took 20 years and $1.8 billion to develop, should prevent 80 percent of dengue-related hospitalizations and up to 93 percent of cases of severe hemorrhagic dengue fever. The vaccine is designed for people ages 9 to 45, and is administered in three separate doses over a six-month period.
Since the start of the immunization program last month, Dengvaxia has been administered to more than 200,000 grade-school students in the capital city of Manila. Of 17,000 people who were injected with the vaccine in the Philippines in February as part of the clinical study, just 27 developed side effects, Health Undersecretary Vicente Belizario told reporters.
According to Health Minister Janette Garin, the $103 million program aims to administer the first dose of the vaccine to 1 million children by June.
The history of developing a vaccine for dengue has been wrought with challenges. An effective vaccine must protect against four closely related viruses that can cause the disease, and researchers have had limited understanding of how the virus affects the immune system. Among other barriers making vaccine development more difficult, there are no easily measurable sign (such as antibodies) that a person is immune to the disease.
The WHO estimates that dengue fever, the world’s most common mosquito-borne virus, infects an estimated 390 million people around the world each year. So far this year, more than 33,000 dengue cases have been recorded in the Philippines alone. Read more…
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).
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..
Dr Shahera Banu, and colleagues from QUT’s Faculty of Health, investigated the impact of climate change on transmission of the mosquito-borne disease and found there would be “devastating” consequences. Dr Banu analysed high-risk areas for dengue fever transmission in the Asia-Pacific region, with particular focus on Dhaka, the capital of Bangladesh and a megacity of 11.8 million people.
Using modelling from the Intergovernmental Panel on Climate Change (IPCC) which predicts an annual average temperature rise for the South Asia region of 3.3 degrees by 2100, the research found there would be a swell of dengue cases. The research has been published in the journals PLOS One and Environment International.
“Without any changes in the socio-economic situation, by the end of this century there will be a projected annual increase of 16,030 cases in Dhaka,” Dr Banu said.”The consequence of this will be devastating.”
The warmer temperatures and humidity would provide optimal conditions for mosquitos to thrive, Dr Banu said. The research collected the monthly number of dengue cases in Dhaka from January 2000 to December 2010 and estimated 377 cases attributable to temperature variation in 2010.
“Assuming a 1 degree temperature increase in 2100, we project an increase of 583 cases, for 2 degrees it would be 2,782 but it is at 3.3 degrees, a rise the IPCC has projected, that will have an overwhelming impact,” Dr Banu said.”Our results show that the monthly temperature and humidity were significantly associated with the monthly dengue incidence in Dhaka.
“These results are consistent with findings of other studies and may assist to forecast dengue outbreaks in different regions.”
Dr Banu said places with similar weather conditions to Dhaka would also likely be at risk from a climate change-driven increase in dengue cases.”We’re hopeful this research will be helpful for improving surveillance of dengue fever and control through effective management and community education programs in Bangladesh and other countries in a similar situation,” she said.
Here’s a report about Singapore’s recent, unexpected dengue outbreak: Epidemic resurgence of dengue fever in Singapore in 2013-2014: A virological and entomological perspective. Long story short: The culmination of the latest epidemic is likely to be due to a number of demographic, social, virological, entomological, immunological, climatic and ecological factors that contribute to DENV transmission. A multi-pronged approach backed by the epidemiological, virological and entomological understanding paved way to moderate the case burden through an integrated vector management approach.
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:
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.”
Can artemisia for dengue be as effective as it is for malaria? There’s a chance – admittedly slim – that artemisia might be effective in treating dengue fever. Last year, researcher Pierre Lutgen wrote : In the 1970s, there were only about nine countries where dengue fever existed but now the number is closer to 60. As of 2010 dengue fever is believed to infect 50 to 100 million people worldwide per year with 1/2 million life-threatening infections There is no cure and no real treatment.
A major dengue fever outbreak took place in Vanuatu in 2014, with several hundred cases. A female person living in Vanuata was infected by this virus. The infection was classified as dengue by clinical analysis in the hospital where she spent a week. She claims to have recovered after drinking Artemisia annua infusion (origin of the herb : Luxembourg). Subsequently several of her relatives suffered from the same symptoms and were all cured in a few days after tea A annua consumption. The Health Authorities confirm that these people were infected by the dengue virus. This is the first in vivo report on the efficiency of Artemisia annua against dengue. It needs of course to be confirmed by clinical trials in accordance with the WHO protocol.
So some clever scientists decided to try artemisia for dengue in the lab. Here’s what they found:
Malaria and dengue are the two most important vector-borne human diseases caused by mosquito vectors Anopheles stephensi and Aedes aegypti, respectively. Of the various strategies adopted for eliminating these diseases, controlling of vectors through herbs has been reckoned as one of the important measures for preventing their resurgence. Artemisia annua leaf chloroform extract when tried against larvae of A. stephensi and A. aegypti has shown a strong larvicidal activity against both of these vectors, their respective LC50 and LC90 values being 0.84 and 4.91 ppm for A. stephensi and 0.67 and 5.84 ppm for A. aegypti. The crude extract when separated through column chromatography using petroleum ether-ethyl acetate gradient (0–100 %) yielded 76 fractions which were pooled into three different active fractions A, B and C on the basis of same or nearly similar R f values. The aforesaid pooled fractions when assayed against the larvae of A. stephensi too reported a strong larvicidal activity. The respective marker compound purified from the individual fractions A, B and C, were Artemisinin, Arteannuin B and Artemisinic acid, as confirmed and characterized through FT-IR and NMR. This is our first report of strong mortality of A. annua leaf chloroform extract against vectors of two deadly diseases. This technology can be scaled up for commercial exploitation.
Author(s): Gaurav Sharma , Himanshi Kapoor , Madhu Chopra , Kaushal Kumar & Veena Agrawa
Reference: Parasitology Research, January 2014, Volume 113, Issue 1, pp 197-209
Access: Click here to go to the Journal
Contact email: email@example.com
So the news so far is good on artemisia and dengue!
For more on artemesia and its modern history, check out this article in Forbes. And watch this video to see where in the dengue virus lifecycle artemisia might be useful:
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.
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:
A report from the Argentine doctors’ organisation, Physicians in the Crop-Sprayed Towns, 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.
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?
[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 otherscalled 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.
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..
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.
Here’s a map showing where the deformed babies are being born:
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.
Why didn’t zika cause an epidemic of birth defects in any other country?
How would you miss a tenfold increase in children born with most of their brain missing?
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?
The Connection Between Dengue and Guillain-Barre (GBS)
Dengue is an arboviral infection that classically presents with fever, joint pain, headaches, skin flush and morbilliform rashes. The incidence of neurological symptoms and complications in dengue varies from 1 to 25 % that include encephalopathy, Guillain–Barre syndrome (GBS), acute motor weakness, seizures, neuritis, hypokalaemic paralysis, pyramidal tract signs, and a few more. Dengue fever as an antecedent infection in GBS is uncommon.
A 34-years-old Sri Lankan Sinhalese male presented with fever, headache and myalgia of 3 days and developed leucopenia and thrombocytopenia without evidence of haemoconcentration. The diagnosis of dengue fever was confirmed as he had positive dengue NS1 antigen test on the third day of fever. He made full recovery and was discharged after 4 days of hospital stay. Six days later, he presented with history of acute flaccid weakness of both lower limbs and upper limbs which was of progressive ascending nature. The electromyography had evidence of demyelinating neuropathy and cerebrospinal fluid showed albuminocytological dissociation. Subsequently, IgM for dengue virus was positive.
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:
Dengue Diagnostic tests are urgently needed. Health workers need to know immediately if your symptoms indicate dengue or a simple fever. For obvious reasons, dengue diagnostic tests are most urgently needed for pediatric (child) dengue cases, where the youngster cannot answer questions. The Medford-based manufacturer of point-of-care tests for HIV and syphilis said the dengue partnership was concluded Monday, the same day that Chembio announced a partnership with Integrated BioTherapeutics Inc. of Maryland…Read more on Newsday
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.
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.
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
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