Cairn's residents threatened with fines over dengue outbreak

Health officials in Cairns in the tropical northern part of Queensland, Australia are battling to contain an outbreak dengue fever in the region.

In the latest attempt to make people sit up and take both notice and action, homeowners are being warned to clean up mosquito breeding areas in their backyards or risk fines of almost $400.


This tough new approach has been adopted as 46 confirmed cases of dengue fever have been reported just one month after the first reported infection in Cairns, with another nine cases pending blood test confirmation.

Local council inspectors are said to be frustrated after finding more mosquito breeding sites despite repeated warnings and say the majority of the public refuse to take the outbreak seriously.

According to the Cairns Regional council's environmental assessment manager, Laurie Phipps, people appear complacent about cleaning out breeding sites, which has resulted in the threats of fines for non-compliance.

Suburbs where dengue fever cases have been identified will be targeted and Cairn's residents urged to remove old car tyres, pot holders, dog bowls or any other containers where water collects - the fines will come under the terms of a health order to clean the area up and could entail an on the spot fine of $375.

Mr Phipps says they have been forced to take this radical action because of a few irresponsible people.

The spread of the type-3 strain of dengue is the third outbreak in the area this year and the Tropical Population Health Services say "lure-and-kill traps" are being placed around dengue-prone neighbourhoods in North Cairns, Whitfield and Parramatta Park.

This mention of such traps will intrigue many responsible residents who would undoubtedly be prepared to take such action but it seems such traps are unavailable commercially but are in fact quite simple to produce at home.

All that is needed is a small black or red container (colours favoured by mosquitoes) and a can of surface spray which will leave a residue on the surface of the container.

But here comes the rub - this must be done once a month, throughout the year - as in the tropics mosquitoes are usually about all year round and experts say jumping up and down and getting excited when an outbreak occurs is akin to closing the stable door after the horse has bolted.

They suggest that if the majority of households practised this level of vigilance dengue outbreaks would occur far less often and say "fogging" (spraying with pesticides) is often ineffective because dengue mosquitoes tend to live indoors.

Queensland Health urges those who experience dengue symptoms to see a doctor immediately rather than wait until after Christmas and say the full extent of the outbreak may not be evident until the new year.

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Ready Reference:

Dengue Fever?

Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes. It is an acute illness of sudden onset that usually follows a benign course with headache, fever, exhaustion, severe joint and muscle pain, swollen glands (lymphadenopathy), and rash. The presence (the "dengue triad") of fever, rash, and headache (and other pains) is particularly characteristic of dengue.

Dengue (pronounced DENG-gay) strikes people with low levels of immunity. Because it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. However, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed.

Dengue goes by other names, including "breakbone" or "dandy fever." Victims of dengue often have contortions due to the intense joint and muscle pain, hence the name breakbone fever. Slaves in the West Indies who contracted dengue were said to have dandy fever because of their postures and gait.

Dengue hemorrhagic fever is a more severe form of the viral illness. Manifestations include headache, fever, rash, and evidence of hemorrhage in the body. Petechiae (small red or purple blisters under the skin), bleeding in the nose or gums, black stools, or easy bruising are all possible signs of hemorrhage. This form of dengue fever can be life-threatening or even fatal.


What areas are at high risk for contracting dengue fever?

Dengue is prevalent throughout the tropics and subtropics. Outbreaks have occurred in the Caribbean, including Puerto Rico, the U.S. Virgin Islands, Cuba, and Central America. Cases have also been imported via tourists returning from areas with widespread dengue, including Tahiti, the South Pacific, Southeast Asia, the West Indies, India, and the Middle East.

Dengue fever is common and may be increasing in Southeast Asia. Thailand, Vietnam, Singapore, and Malaysia have all reported an increase in cases. According to the World Health Organization, there are an estimated 50 million cases of dengue fever with 500,000 cases of dengue hemorrhagic fever requiring hospitalization each year. Nearly 40% of the world's population lives in an area endemic with dengue.


How is dengue contracted?

The virus is contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. The mosquito flourishes during rainy seasons but can breed in water-filled flower pots, plastic bags, and cans year-round. One mosquito bite can inflict the disease.

The virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.


What are the signs and symptoms of dengue?

After being 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.


How is dengue fever treated?

Because dengue 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).


What is the outcome with typical dengue?

Typical dengue does not result in death. It is fatal in less than 1% of cases. The acute phase of the illness with fever and myalgias lasts about one to two weeks. Convalescence is accompanied by a feeling of weakness (asthenia), and full recovery often takes several weeks.


What is dengue hemorrhagic fever?

Dengue hemorrhagic fever (DHF) is a specific syndrome that tends to affect children under 10. It causes abdominal pain, hemorrhage (bleeding), and circulatory collapse (shock). DHF is also called Philippine, Thai, or Southeast Asian hemorrhagic fever and dengue shock syndrome.

DHF starts abruptly with high continuous fever and headache. There are respiratory and intestinal symptoms with sore throat, cough, nausea, vomiting, and abdominal pain. Shock occurs two to six days after the start of symptoms with sudden collapse, cool, clammy extremities (the trunk is often warm), weak pulse, and blueness around the mouth (circumoral cyanosis).

In DHF, there is bleeding with easy bruising, blood spots in the skin (petechiae), spitting up blood (hematemesis), blood in the stool (melena), bleeding gums, and nosebleeds (epistaxis). Pneumonia is common, and inflammation of the heart (myocarditis) may be present.

Patients with DHF must be monitored closely for the first few days since shock may occur or recur precipitously. Cyanotic (bluish) patients are given oxygen. Vascular collapse (shock) requires immediate fluid replacement. Blood transfusions may be needed to control bleeding.

The mortality, or death rate, with DHF is significant. It ranges from 6%-30%. Most deaths occur in children. Infants under a year of age are especially at risk of dying from DHF.


How can dengue fever be prevented?

The transmission of the virus to mosquitoes must be interrupted to prevent the illness. To this end, patients are kept under mosquito netting until the second bout of fever is over and they are no longer contagious.

The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In nations 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.

Wear long pants and long sleeves. For personal protection, use mosquito repellant sprays that contain DEET when visiting places where dengue is endemic. Limiting exposure to mosquitoes by avoiding standing water and staying indoors two hours after sunrise and before sunset will help. The Aedes aegypti 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.

There is currently no vaccine available for dengue fever. There is a vaccine undergoing clinical trials, but it is too early to tell if it will be safe or effective.