By. Dr. Eduardo Gonzales
On Monday, July 15, the Department of Health (DOH) declared a national dengue alert in response to the sharp rise in reported cases of the disease nationwide during the first half of the year. From Jan. 1 to June 29, 106,630 dengue cases have been reported nationwide, an 85 percent increase from the 57,564 cases reported over the same period last year.
DOH Secretary Francisco Duque III, however, clarified that there is no national epidemic as only five regions to date have exceeded the epidemic threshold for the number of cases—Western Visayas, Calabarzon, Central Visayas, Soccsksargen, and Northern Mindanao. The following regions, on the other hand, are being monitored after exceeding the alert threshold: Ilocos region, Cagayan Valley, Calabarzon, Bicol region, Eastern Visayas, Zamboanga Peninsula, Davao region, Bangsamoro Autonomous Region in Muslim Mindanao, and Cordillera Administrative Region.
The declaration, according to Secretary Duque, simply aims to raise awareness among the public, and, more important, in communities where signs of early dengue increases are evident. With increase awareness, with hope, people will take the necessary actions to stem the ongoing dengue rampage.
What dengue is all about
Dengue is caused by four types of Flaviviruses. These viruses are not capable of human-to-human transmission. They are transmitted to humans by the bite of either of two species of the mosquito genus Aedes aegypti (the main vector in the Philippines) and albopictus.
Dengue is generally a mild, self-limiting febrile illness, but it sometimes complicates and gives rise to severe dengue that can be fatal. Recovery from infection from one type of dengue virus provides lifelong immunity against that particular type. Subsequent infection (secondary infection) by any of the other three types, however, carries an increased risk of developing severe dengue.
According to the World Health Organization (WHO), dengue should be suspected when a high fever (40°C) is accompanied by two of the following symptoms: severe headache, pain behind the eyes, muscle and joint pains, nausea, vomiting, swollen glands, or rash. Symptoms usually last for two to seven days. People who think they have dengue should seek medical help.
The warning signs of severe dengue, on the other hand, which usually appear three to seven days after the start of the illness and usually after the fever has subsided, include severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums, fatigue, restlessness, and blood in vomit. People who are suspected of having severe dengue should be brought to the hospital.
Severe dengue is a potentially deadly complication due to plasma leaking, fluid accumulation, respiratory distress, severe bleeding, or organ impairment.
What you need to know about the dengue mosquito
The Aedes aegypti mosquito, minus its legs, is only three to four millimeters long. It stands out among mosquitos because it has white dots on its back and head and white stripes on its legs. Only the female mosquito bites and it does so because animal blood is needed for proper development of its eggs. The mosquito prefers human blood over blood of other animals and it loves to bite during the day. It acquires the dengue virus when it bites and feeds on the blood of a person with dengue. The virus then proliferates within, but does not harm the mosquito. Eight to 11 days after feasting on infected blood, the mosquito becomes infective, can transmit the virus to any human it bites, and remains so for the rest of its life, which can be anywhere from 15 to 65 days.
From Jan. 1 to June 29, 106,630 dengue cases have been reported nationwide, an 85 percent increase from the 57,564 cases reported over the same period last year.
The female Aedes mosquito, which has a flight range of up to 300 meters, breeds in stagnant water. It lays up to a hundred eggs at a time, in every place where non-running water exists— flower vases, jars, pots, bottles, drums, roof gutters, drains, old tires, tree cavities, plant stumps, etc. The eggs hatch into larvae (wrigglers) in a week. Another week later, the larvae transform into pupae, which become adult mosquitoes in one to three days.
Measures to prevent dengue
Arguably, the best way to keep the number of dengue cases down is by stopping its mosquito vector from breeding and protecting people from getting bitten by the mosquito. To this end, the following measures will be of great help:
- Screen your house. Alternately, use mosquito nets, mosquito repellents, or mosquito coils (“katol”) and mats.
- Isolate persons with dengue fever in a screened room for at least five days from the onset of symptoms. This will prevent mosquitoes from biting the person and acquiring the virus.
- Eliminate all possible breeding places of mosquitoes in your neighborhood. Fill potholes. Cover water containers and septic tanks. Do not allow empty cans, soft drink bottles, spare tires, etc. to accumulate water. Ensure that drains and gutters are not clogged and that water flows freely in sewage lines. Lastly, dispose of garbage properly and regularly