Researchers have come up with a vaccine that is effective against the four strains of the deadly disease that has proven effective on trials using monkeys. Annually, there are a reported million cases of infection that comes mostly from the tropics and people who have been to such areas. Two of the four types are deadly, hemorrhagic fever and dengue shock syndrome the tetravalent vaccine hopes to address. Proteins from all four viral strains were combined along with an adenovirus agent that resulted in the vaccine that promises to be the best yet.
(more…)

Dengue Hemorrhagic Fever(DHF) is actually an old virus that is considered to be one of the most deadliest the world over due to their ability to jump species. Spread by the Aedes Aegypti mosquito, that is differentiated by it’s daytime feeding habits, it has silently killed millions the world over. The incubation period is short accompanied by severe fever that usually lasts three days, after which, without proper monitoring and care death is sure to occur. Mostly restricted to areas that are in the tropics zone due to the inability of its host to survive in cold weather. Outbreaks have been well documented and a cure is still out of sight. The disease is however being tackled from different angles, one of them targets the disease at its source, the mosquito which can be infected with a virus that halves its lifespan thus lessening its ability to spread it by half. The danger came when man invented mass travel wherein people and machines could transport the disease carrying mosquitoes all over the globe.

画像提供：bbc.co.uk

テング熱の症状は、約5日間から8日間の潜伏期間を経た後に突然発症します。 その症状には、熱や悪寒、頭痛、目の痛み、リンパ節の肥大、顔面の紅潮、腰の痛み、極度の脱力感足や関節の激しい痛みなどがあります。
病状の前兆は約2週間から3週間に及びます。 その後、熱が上下し、 腕や足に発疹ができ、胸部や腹部に広がります。 また、足のかかとや手のひらが赤く腫れます。 発熱や発疹、頭痛の症状が一度に出現するこの特徴は、テング熱の三兆候と呼ばれています。 脱力感と疲労は数週間続くこともありますが、大抵の場合は正常な状態に回復します。 一度感染すると、免疫システムは約一年間にわたり再感染を防止する細胞を作り続けます。

Image Source: bp1.blogger.com

The worst kind of dengue is the shock syndrome, where your whole circulatory system just shuts down though it’s rare. Symptoms of dengue can vary but are often associated with a fever, headaches, joint pain and a rash. For most people it is not fatal. There is no specific treatment or vaccine for dengue fever. Once contracted, doctor’s advice is to take fluids and rest. The pathogenesis of dengue shock syndrome remains unclear. It is suggested that antibody-dependent enhancement is involved in these more serious conditions when infected the second time around with a different serotype of the virus. After an initial period of protection, antibodies from the primary infection can cross-react with other dengue virus serotypes but have waned to non-neutralizing levels leading to increased virus replication and immune activation including massive cytokine release also known as a cytokine storm.

画像提供：mages.inmagine.com

雨期には、蚊が大量に発生し、蚊の繁殖場所となる淀んだ水だまりができます。 蚊は一年を通して植木鉢やビニール袋、缶に溜まった水の中で繁殖します。 多くの子供は特に学校においてこのような環境に置かれ、長袖のズボンとシャツの着用を勧められています。 また、蚊から身を守るために、蚊よけスプレーやJohnson and Johnsonの子供用のOff Lotionなど、効果的でネバネバ感を与えないDEETを含むローションの使用を勧められています。

蚊の一刺しは、テング熱という病気を引き起こします。 テング熱を患う患者を刺した縞模様のネッタイシマカが、他の人を刺すことでウィルスは感染します。 ネッタイシマカは日中に人を刺しますが、特に日の出を日の入りの時間に活動が活発です。 そして、一日のどの時間でも人を刺す可能性があり、特に都市部の家や他の住居によく生息します。

テング熱の予防には、テング熱を発生させるウィルスをもつ蚊のコントロールと撲滅が必要となります。 テング熱に苦しむ地域では、古いタイヤやごみ入れ、植木鉢から淀んだ水を取り除くことが求められます。 政府による蚊を減らす運動は、テング熱の抑制の役には立ちますが、あまり効果を得ていません。
テング熱のウィルスを持っている蚊に刺された場合は、その症状や兆候が現れるまで３日から１５日の潜伏期があります。 テング熱にかかると、寒気や頭痛、目の動作に伴う痛み、腰痛などの症状がまず現れます。 また、症状発生から一時間の間に足や関節の痛みが現れます。 体温が４０度近くに急激に上がり、心拍数の低い状態（序脈）や低血圧（高血圧）を伴います。 また、眼が充血します。 赤い発疹や青白い発疹が顔面に現れ、そして消え失せます。 また、頸部や鼠径部の分泌腺（リンパ節）が腫れることも多くあります。 熱やテング熱の他の兆候は二日から四日間続き、多量の発汗とともに急激な体温の低下（解熱）が生じます。 この症状の発生後、約一日にわたり体温が通常の状態に回復し、健康的な感覚が戻ります。 そして、二度目の急激な体温の上昇が起こります。 熱を伴う特徴的な発疹が発生し、四肢に広がり顔以外の体全体に広がります。 手のひらとかかとが赤く腫れ上がることもあります。 この兆候が現れた場合には、医師に相談し、適切な診断を得るために血液検査を受けることを勧めます。
テング熱のウィルスは感染性がなく、人から人へ直接に伝染しません。 人から蚊へ、蚊から人へとの経路を通じてのみ感染します。 テング熱はウィルス性の病気のため、特殊な薬や抗生物質が存在せず、ワクチンは現在手に入りません。 典型的なテング熱における治療は、症状を緩和する以外の方法はなく、 休養と適度な水分を保つために液体の摂取が重要となります。 アスピリンと非ステロイド系の抗炎症薬は使用できません。 激しい頭痛と関節痛と筋肉の痛み（筋肉痛）に対しては、アセトアミノフェン（タイレノール）やコデインが使用されることがあります。
現在臨床試験中のワクチンが存在しますが、その安全性や効果における確信はまだ先のことになりそうです。

Image Source: bbc.co.uk

Symptoms of dengue fever appear suddenly after a period of incubation that lasts about five to eight days. It includes fever, chills, headache, eye pain, red eye, enlarge lymph nodes, a red flush to the face, lower back pain, extreme weakness and severe aches in the legs and joints.
The initial signs of illness last about two to three days. After this, the fever fluctuates and a rash appears in the arms, legs, and spreading to the chest and abdomen. The soles of the feet and the palms of the hands are swollen and turn red. The combination these characteristics of having fever, rash and headache are called the dengue triad. Although weakness and fatigue may last several weeks, most people recover fully from it. Once infected, the immune system keeps producing cells that prevent it from re-infection for about a year.

Image Source:images.inmagine.com

During the rainy season mosquito flourishes and stagnant water builds up that can be the can be their breeding ground. They can also breed in water-filled flower pots, plastic bags, and cans year round. Most kids especially in school and are prone to this conditions our advised to wear long pants and long sleeves. For personal protection, they are asked to use mosquito repellant sprays or lotions that contain DEET like Off Lotion for kids by Johnson and Johnson that is so effective with non greasy feel.

One mosquito bite can inflict the disease called Dengue Fever. A virus contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. This mosquito is a daytime biter with peak periods of biting around sunrise and sunset. It may bite at any time of the day and is often hidden inside homes or other dwellings, especially in urban areas.

The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In places plagued by dengue fever, people are urged to empty stagnant water from old tires, trash cans, and flower pots. Governmental initiatives to decrease mosquitoes also help to keep the disease in check but have been poorly effective.
If bitten by a mosquito carrying the virus, the incubation period ranges from three to 15 (usually five to eight) days before the signs and symptoms of dengue appear. Dengue starts with chills, headache, pain upon moving the eyes, and low backache. Painful aching in the legs and joints occurs during the first hours of illness. The temperature rises quickly as high as 104° F (40° C), with relative low heart rate (bradycardia) and low blood pressure (hypotension). The eyes become reddened. A flushing or pale pink rash comes over the face and then disappears. The glands (lymph nodes) in the neck and groin are often swollen. Fever and other signs of dengue last for two to four days, followed by rapid drop in temperature (defervescence) with profuse sweating. This precedes a period with normal temperature and a sense of well-being that lasts about a day. A second rapid rise in temperature follows. A characteristic rash appears along with the fever and spreads from the extremities to cover the entire body except the face. The palms and soles may be bright red and swollen. If this signs show kindly consult a doctor and have your blood tested for accurate diagnosis.
The Dengue Fever virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway. There is currently no vaccine available for dengue fever because it is caused by a virus; there is no specific medicine or antibiotic to treat it. For typical dengue, the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important. Aspirin and nonsteroidal anti-inflammatory drugs should be avoided. Acetaminophen (Tylenol) and codeine may be given for severe headache and for the joint and muscle pain (myalgia).
There is a vaccine undergoing clinical trials, but it is too early to tell if it will be safe or effective.

Image Source: www.library.thinkquest.org
The rate of deaths associated with dengue fever is now becoming less. But this does not mean that we should not put concern on it. Many of my friends had dengue and according to them, it is not easy. We should keep in mind that dengue fever is fatal and it must be prevented.
As what people who are associated with the health department say, we must prevent it. And this is prevented by particularly, keeping our homes clean—inside and outside.
Aedes Aegypti, the kind of mosquito that carries the disease, lays their eggs in stagnant water which is found in our homes. Change the water in flower vases every other day to prevent the mosquitoes from laying their egg there. And keep the water containers covered,.
For yourself, see to it that you apply mosquito repellant lotion. Several are available in the market with variations of scents.
Bear in mind that prevention is better than cure.

According to the English number one university, Oxford, about 20 million people are expected to die of Dengue annually worldwide. But fear not for they have introduced a new technique to fight the disease, it is called Oxitec Ltd, and it is one of the 39, selected from a field of 273, that has been named as Technology Pioneer 2008 by the World Economic Forum. It uses genetics and molecular biology which make male mosquitoes sterile thus making them unable to reproduce. “This prize is an external validation of our technology and our business plan,” Dr. Luke Alphey, the developer of the technology told the BBC.

Scientists, with the help of local children in Vietnam have found an alternative way to fight off dengue-carrying mosquitoes. They found out that there are certain types of water bugs that destroy said mosquitoes. They have been placing these bugs in nine areas of north and central Vietnam and they have observed that cases of dengue fever in said areas have been reduced to zero over a five year period. One of the scientists in this research, Professor Brian Kay, from the Queensland Institute of Research, said that this scheme is being extended to 37 other areas of Vietnam but wished to see it used on a global scale.

Source: BBC News