KARACHI, Nov 30: The city has been in the grip of fear and panic since the report of first haemorrhagic fever case at a private hospital. The death of Dr Yusra Afaq at a private hospital and a subsequent strike called by the house-job officers jolted the government functionaries. The health secretary ultimately gave a break up saying that 42 cases of haemorrhagic fever were reported in the city and five people died of the haemorrhagic fever during the past three months. One of the patients was confirmed Crimean-Congo haemorrhagic fever. However, the patient recovered and went to his native village in Balochistan.

Later, eight more cases of haemorrhagic fever were reported at the Civil Hospital and the Jinnah Postgraduate Medical Centre. Doctors suspected that the patients had been suffering from Dengue haemorrhagic fever instead of the Crimean-Congo haemorrhagic fever as their initial examination of blood showed the prevalence of Dengue virus.

According to medical experts, viral hemorrhagic fevers are a group of illnesses that are caused by several distinct families of virus i.e. Arenavirus, Filloviridae, Bunyaviridae, and Flavivirus. Some of them cause mild illness while others can cause severe, life threatening disease, which include Lassa fever, Marburg, Ebola, Bolivian, Korean, Crimean-Congo, and Dengue hemorrhagic fever.

Dengue is a mosquito-borne infection which in the recent years has become a major international public health concern. Dengue is found in the tropical and sub-tropical regions around the world, predominantly in the urban and semi-urban areas.

According to the World Health Organization, Dengue hemorrhagic fever (DHF), a potentially lethal complication, was first recognized in the 1950s during the dengue epidemics in the Philippines and Thailand, but today the DHF affects Asian countries the most and has become one of the leading causes of deaths among children.

Four distinct, but closely related, viruses cause dengue. Recovery from infection by one provides lifelong immunity against that serotype but confers only partial and transient protection against subsequent infection by the other three. There is good evidence that sequential infection increases the risk of more serious disease resulting in the DHF.

Some 2,500 million people — two fifths of the world’s population — are now at risk from dengue. The WHO currently estimates there may be 50 million cases of dengue infection worldwide every year.

An estimated 500,000 cases of the DHF require hospitalization each year, of which a very large proportion is children. At least 2.5 per cent of the cases die, although case fatality could be twice as high. Without proper treatment, DHF case fatality rates can exceed 20 per cent. With modern intensive supportive therapy, such rates can be reduced to less than one per cent.

Dengue haemorrhagic fever is a potentially deadly complication that is characterized by high fever, haemorrhagic phenomena — often with the enlargement of the liver — and in severe cases, circulatory failure. The illness commonly begins with a sudden rise in temperature accompanied by facial flush and other non-specific constitutional symptoms of dengue fever. The fever usually continues for two to seven days and can be as high as 40-41 degrees Centigrade, possibly with febrile convulsions and haemorrhagic phenomena.

There is no specific treatment for dengue fever. However, careful clinical management by experienced physicians and nurses frequently saves the lives of the DHF patients. With appropriate intensive supportive therapy, mortality may be reduced to less than one per cent. Maintenance of the circulating fluid volume is the central feature of the DHF case management.

The study of various international organizations showed that the dengue hemorrhagic fever was characterized by a fever that lasts from two to seven days, with general signs and symptoms that could occur with many other illnesses (eg, nausea, vomiting, abdominal pain, and headache).

This stage is followed by hemorrhagic manifestations, tendency to bruise easily, or other types of skin haemorrhages, bleeding nose or gums, and possibly internal bleeding. The smallest blood vessels (capillaries) become excessively permeable, allowing the fluid component to escape from the blood vessels. This may lead to the failure of the circulatory system and shock, followed by death.

There is no specific medication or treatment for a dengue infection. Persons who think they have dengue should use analgesics (pain relievers) with acetaminophen and avoid those containing aspirin. They should also rest, increase fluid intake and consult a physician, the study shows.

The Crimean-Congo hemorrhagic fever (CCHF) is a widespread tick-borne viral disease, a zoonosis of domestic animals and wild animals that may affect humans. According to the WHO, the CCHF is a viral haemorrhagic fever of the Nairovirus group. The disease is endemic in many countries in Africa, Europe and Asia, and during 2001, cases of outbreak have been recorded in Kosovo, Albania, Iran, Pakistan, and South Africa.

The disease was first described in Crimea in 1944 and given the name Crimean hemorrhagic fever. In 1969, it was recognized that the pathogen causing Crimean hemorrhagic fever was the same as that responsible for an illness identified in 1956 in the Congo and linkage of the two place names resulted in the current name for the disease and the virus.

The length of the incubation period for the illness appears to be dependant on the mode of acquisition of the virus. Following infection via tick bite, the incubation period is usually one to three days with a maximum of nine days. The onset of symptoms is sudden, with fever, myalgia (aching muscles), dizziness, neck pain and stiffness, backache, headache, sore eyes and photophobia (sensitivity to light). There may be nausea, vomiting and sore throat early on, which may be accompanied by diarrhoea and generalized abdominal pain.

Over the next few days, the patient may experience sharp mood swings, and may become confused and aggressive. After two to four days, the agitation may be replaced by sleepiness, depression and lassitude, and the abdominal pain may localize to the right upper quadrant, with detectable hepatomegaly (liver enlargement).

Other clinical signs which emerge include increase in heart beats, enlarged lymph nodes, and a petechial rash (a rash caused by bleeding into the skin), both on internal mucosal surfaces, such as in the mouth and throat, and on the skin. The petechiae may give way to ecchymoses (like a petechial rash, but covering larger areas) and other haemorrhagic phenomena such as melaena (bleeding from the upper bowel, passed as altered blood in the faeces), haematuria (blood in the urine), epistaxis (nosebleeds) and bleeding from the gums. There is usually evidence of hepatitis. The severely ill may develop hepatorenal (i.e. liver and kidney) and pulmonary failure after the fifth day of illness.

The mortality rate from CCHF is approximately 30 per cent, with death occurring in the second week of illness. In those patients who recover, improvement generally begins on the ninth or tenth day after the onset of the illness.

The tick vectors are numerous and widespread. Tick control with acaricides (chemicals intended to kill ticks) is only a realistic option for well-managed livestock production facilities. Patients with suspected or confirmed CCHF should be isolated and cared for using barrier nursing techniques. Specimens of blood or tissues, taken for diagnostic purposes, should be collected and handled using universal precautions, according to the WHO.