MUCH ADO ABOUT DENGUE FEVER

If there’s a deadly disease these days that needs no introduction, it’s dengue fever and its lethal form, dengue hemorrhagic fever (DHF). In fact, the Department of Health has issued a national dengue epidemic.

Dengue fever is characterized by high fever, severe headache, pain behind the eyes, and muscle and joint aches. Many people, including doctors, mistake dengue for influenza and flu-like diseases, so it often goes untreated until symptoms become severe and the patient goes into shock.

It happens when DHF strikes in. “There’s often a rash in dengue while there’s none in flu,” explained Dr. Allan Schapira, an epidemiologist who was then with the regional office of the World Health Organization (WHO) when interviewed by this author. “Fever caused by dengue tends to last almost a week, while that of flu disappears after three to five days.”

After a dengue patient goes into shock, it’s usually a matter of time before multi-organ failure occurs and death become inevitable. This terrifying scenario is characterized by high continuous fever (40-41 degrees) lasting up to seven days that may be accompanied by loss of appetite, nausea, vomiting, abdominal pain and bleeding from the skin, nose or gums.

In the worst cases, the patients’ condition may suddenly deteriorate after a few days of fever, and they may die within 24 hours. “Death often results from bleeding in the brain, intestines or other organs,” said Dr. Lulu Bravo, a professor at the University of the Philippines College of Medicine.

Dr. Bruno Guy, an immunologist from France, said that dengue’s mortality rate is quite low: only 2.5% of severe dengue can lead to death. It’s even lower in the Philippines: the case fatality rate, according to the health department, is 0.44%.

So far, 456 reported deaths have already been reported from the 106,630 cases recorded from January 1 to June 29, 2019. This is already alarming. So much so that some health sectors are already suggesting the revival use of the controversial anti-dengue vaccine called Dengvaxia.

“If Dengvaxia is proven effective to those who already had dengue in the past, then its application to these individuals (who were infected with dengue virus) will surely cause the decline of the overall number of cases of dengue which plague the residents of this country,” said presidential spokesperson Salvador S. Panelo in a statement.

Dengue strikes mostly children although adults are not spared. As such, parents whose children are infected with the dengue virus resort to using unproven means to raise the blood platelets.

Among the reported medications used are tawa-tawa (Euphorbia hirta), balut, papaya leaves, camote tops, and magic balls. These are “effective,” according to some of those who have tried them.

A study conducted by students of the University of Sto. Tomas showed that administering tawa-tawa decoction to animal models help improve their healing mechanisms. “Tawa-tawa was able to promote cell production, and prevents platelet destruction,” the study found out. “Likewise, the improvement in the cell bleeding time and clotting time provided evidence that the indigenous plant can preserve and promote the hemostatic function of platelets.”

Although tawa-tawa capsules are currently registered with the Food and Drug Administration (FDA), the health department is not promoting it as a cure for dengue. The FDA’s registration is “only as a supplement with no therapeutic claims,” according to DOH Undersecretary Eric Domingo. He added that it has still to “undergo a lot of clinical trials before their therapeutic values can be proven.”

Actually, it’s not about low platelet that counts when it comes to dengue. “Low platelet is not the main problem during dengue infection,” clarifies Dr. Anna Nina Natalia L. Tayo, an internist, neurologist and psychiatrist. “It is just one of the warning signs of a possible transition of a mild dengue fever to its severe form but not the hallmark of dengue hemorrhagic fever.”

Based on available studies, “there is a mild to moderate decrease in platelets of dengue patients between the third to the seventh day and significant decrease on day 4. However, it starts to go up on its own on the eighth or ninth day of the disease. With or without herbal medications, platelets will naturally increase during the recovery phase.”

The problem actually lies on plasma leakage. “This phenomenon is the hallmark of severe dengue and at the same time a life-threatening complication that results into dehydration and low blood volume that may progress into circulatory collapse (shock) if not treated adequately,” Dr. Tayo explained. “Once shock has set in, the patient is now classified as having dengue shock syndrome. If shock is not reversed, it leads to disseminated intravascular coagulopathy, multiple organ failure, and/or death.”

Plasma, medical science tells us, makes up more than half (55%) of the total blood volume and 20% of the total body water. “In the event of continued leakage,” Dr. Tayo said, “this results in dehydration and low blood volume.”

Dr. Richard T. Mata, a WHO consultant on dengue, says dehydration occurs when a person loses more fluid and his body doesn’t have enough water and other fluids to carry out its normal functions.

Dehydration causes intestinal ulcer that causes bleeding. “And because the platelets are low, the bleeding becomes severe. But if there was no dehydration, there will be no ulcer and thus no bleeding – even if the platelets are low,” he explains. “So, it still boils down to dehydration.”

Dehydration also causes kidney failure, which result from the decrease in urine output. “This causes the water to be retained in the lungs thereby creating congestion that can kill the patients,” he says.

A joint statement by the Philippine Pediatric Society and the Pediatric Infectious Disease Society of the Philippines advised “judicious use of intravenous fluid” among hospitalized patients “should be observed as over hydration places the patient at risk of pulmonary edema and other grave complications.”

This brings back to plasma leakage. “If plasma leaks into lung tissues, it causes accumulation of fluid resulting into pulmonary edema (swelling) which makes breathing difficult,” Dr. Tayo said. “When worse comes to worst, the patient might need mechanical ventilation (respirator) to supporting breathing and alleviate low oxygenation (hypoxemia).”

If the fluid accumulates in the abdominal cavity, ascitis results. “The abdomen distends because of the fluid formation in the abdominal cavity which can lead to several life-threatening complications,” Dr. Tayo pointed out.

Tayo’s endpoint: “Low platelet is not the bad guy in dengue fever. The real culprit for deaths in dengue is plasma leakage and treatment for this dreaded complication remains to be timely calculated intravenous fluid replacement and not tawa-tawa or papaya extracts or any herbal concoction.”

An ounce of prevention is better than a pound of cure, so goes a popular saying. “Prevention is crucial,” Dr. Bravo said. “Unless we take concerted action to educate our people now, dengue will continue to take its toll in the country.”

The best way to beat dengue fever is not to be bitten by dengue-carrying mosquitoes. When going out, people are advised to wear long-sleeved shirts and long pants. When indoors, it is advisable to stay in air-conditioned or screened areas. All windows and doors must have screens to avoid mosquitoes from getting in. Children must not play near still water.

Eliminating breeding sites for mosquitoes is another way. “I am calling on the public to clean their surroundings every day,” Senator Richard Gordon told Philippine Star. “Destroy all the breeding sites of mosquitoes by cleaning canals, removing stagnant, clean water that can be found in places where these may go unnoticed such as flower vases and other plants, old tires, construction debris, uncollected garbage, and gutters, among others.”