21 January 2011

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Congo CCHF) virus – Know the Treatment and How to prevent and control spread of Congo or CCHF Virus

Congo CCHF - virus – Know the Treatment and How to prevent and control spread of Congo or CCHF Virus,Infection

What is a viral hemorrhagic fever?
A viral hemorrhagic fever is a viral disease, which has a tendency to disrupt
the clotting of the blood, so that patients may develop uncontrolled bleeding.
Usually fever, body aches, and other flu-like symptoms also are seen.

Many common diseases can resemble viral hemorrhagic fever, but the term is
reserved for a particular group of diseases associated with a high death
(fatality) rate.

In addition to CCHF they include Lassa fever, Rift Valley
fever, Alkhumra, Omsk hemorrhagic fever, Kyasanur forest disease,
Argentine, Bolivian, Brazilian, and Venezuelan hemorrhagic fevers (caused
by Junin, Machupo, Sabia, and Guanarito viruses, respectively), and
Marburg and Ebola hemorrhagic fevers.

The National Institute of Virology (NIV) has confirmed the positive testing of Crimean-Congo Haemorrhagic Fever (CCHF) virus, identified for the first time in India, which has claimed three lives in Gujarat.

The geographic range of CCHF virus is the most extensive among the tickborne viruses that affect human health, and the second most widespread of all medically important arboviruses, after dengue viruses

CCHF has become one of the most geographically widely distributed tick-borne diseases in the world; the disease, or the presence of the virus, has been reported from at least 31 countries in Africa, Asia, southeast Europe, and the Middle East.

Where does the CCHF virus come from?
A: The virus is transmitted mainly by Hyalomma ticks, adults of which have dis-
tinctive brown and white bands on their legs.
The virus can remain in the ticks for long periods, and even pass through the eggs to infect the next generation of ticks.

Immature Hyalomma ticks (larvae and nymphs) feed on ground-frequenting
(or ground-feeding) birds (guinea fowl, partridges, rooks) and small mammals
up to the size of hares.
Adult Hyalomma ticks feed on livestock such as cattle,sheep, and goats, as well as on wild animals such as antelope, wild boar, and ostriches.

Animals bitten by infected ticks do not develop the disease, but can circulate
the virus in their blood for a few days, up to 1 week, and thereafter become
immune to further infection.
Non infected ticks become infected if they feed on the animals during the short period when virus is in circulation, thus ensuring that the virus is perpetuated.

The Congo virus, which surfaced in Ahmedabad, killed three persons including a doctor and nurse who treated the first victim - a woman from Kolat village in Sanand taluka of the district.

The mortality rate from CCHF is approximately 30%, 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 illness.

Crimean-Congo haemorrhagic fever (CCHF) is a viral haemorrhagic fever of the Nairovirus group.

The disease was first described in the Crimea in 1944 and given the name Crimean haemorrhagic fever.
In 1969 it was recognized that the pathogen causing Crimean haemorrhagic fever was the same as that responsible for an illness identified in 1956 in the Congo and linkage of the 2 place names resulted in the current name for the disease and the virus. CCHF is a severe disease in humans, with a high mortality rate.

The virus which causes CCHF is a Nairovirus, a group of related viruses forming one of the five genera in the Bunyaviridae family of viruses.
All of the 32 members of the Nairovirus genus are transmitted by argasid or ixodid ticks, but only three have been implicated as causes of human disease:

During the summers of 1944 and 1945 over 200 cases of an acute, hemorrhagic, febrile illness occurred in Soviet troops rescuing the harvest following the ethnic cleansing of the Crimean Tatars.
Soviet scientists first identified the disease they called Crimean hemorrhagic fever in 1944 and established its viral etiology by passage of the virus through human "volunteers"

CCHF or Congo reservoirs and vectors –
A reservoir is a place or a zone where a supply is kept in store.
Reservoir refers to a carrier of a virus or parasite for which they are not pathogenic.
Pathogenic means Capable of causing disease or Originating or producing disease.

Vector means any agent (person or animal or microorganism) that carries and transmits a disease; "mosquitos are vectors of malaria and yellow fever"

The CCHF virus may infect a wide range of domestic and wild animals. Many birds are resistant to infection, but ostriches are susceptible and may show a high prevalence of infection in endemic areas. Animals become infected with CCHF from the bite of infected ticks.

A number of tick genera are capable of becoming infected with CCHF virus, but the most efficient and common vectors for CCHF appear to be members of the Hyalomma genus.

The most important source for acquisition of the virus by ticks is believed to be infected small vertebrates on which immature Hyalomma ticks feed.
Once infected, the tick remains infected through its developmental stages, and the mature tick may transmit the infection to large vertebrates, such as livestock. Domestic ruminant animals, such as cattle, sheep and goats, are viraemic (virus circulating in the bloodstream) for around one week after becoming infected.

How the Humans get infected by Congo or CCHF virus?
Humans who become infected with CCHF acquire the virus from direct contact with blood or other infected tissues from livestock during this time, or they may become infected from a tick bite.
The majority of cases have occurred in those involved with the livestock industry, such as agricultural workers, slaughterhouse workers and veterinarians.
The virus is transmitted to humans by the bite of Ixodid tick (mostly of the Hyalomma genus) or by contact with blood or tissues from human patients or infected livestock

The length of the incubation period for the illness appears to depend 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 incubation period following contact with infected blood or tissues is usually five to six days, with a documented maximum of 13 days.

What are symptoms of Congo once it is acquired by Human?
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 tachycardia (fast heart rate), lymphadenopathy (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.

What is the procedure to Diagnosis of CCHF or Congo Virus?
Diagnosis of suspected CCHF is performed in specially-equipped, high biosafety level laboratories. IgG and IgM antibodies may be detected in serum by enzyme-linked immunoassay (the "ELISA" or "EIA" methods) from about day six of illness. IgM remains detectable for up to four months, and IgG levels decline but remain detectable for up to five years.

Patients with fatal disease do not usually develop a measurable antibody response and in these individuals, as well as in patients in the first few days of illness, diagnosis is achieved by virus detection in blood or tissue samples.

There are several methods for doing this.
The virus may be isolated from blood or tissue specimens in the first five days of illness, and grown in cell culture.
Viral antigens may sometimes be shown in tissue samples using immunofluorescence or EIA.
More recently, the polymerase chain reaction (PCR), a molecular method for detecting the viral genome, has been successfully applied in diagnosis.

Treatment for Congo or CCHF –

General supportive therapy is the mainstay of patient management in CCHF. Intensive monitoring to guide volume and blood component replacement is required.
The antiviral drug ribavirin has been used in treatment of established CCHF infection with apparent benefit.
Both oral and intravenous formulations seem to be effective.
The value of immune plasma from recovered patients for therapeutic purposes has not been demonstrated, although it has been employed on several occasions.

Ribavirin aerosol is antiviral drug that could be also used in viral hemorrhagic fever syndromes. Besides Crimean-Congo hemorrhagic fever (CCHF), it is used in Lassa fever

Note - Please do not take medicine without doctors advice.

Treatment of Crimean-Congo hemorrhagic fever -
Disseminated intravascular coagulation and CCHF

Disseminated intravascular coagulation (DIC) results from activation of coagulation in the
vascular tree. Accelerated platelet consumption is almost always seen. DIC can be distinguished
from immune thrombocytopenia by finding prolongation of the prothrombin and partial thromboplastin times, decreased plasma fibrinogen, and elevated plasma fibrin–fibrinogen split products.

DIC can be seen with infections (e.g., viral, Rickettsial, bacterial, malarial infections);
obstetric catastrophes (abruptio placentae and the retained dead fetus syndrome); malignancies;trauma; and vascular abnormalities such as giant hemangiomas and aortic aneurysms.
Generally,the treatment should be directed toward correcting the underlying cause. Support with plasma and platelet transfusions may be required for bleeding complications until the cause has been corrected.
The thrombocytopenia gradually resolves as the infection is controlled

An algorithm for the case management of Suspected CCHF
Evaluation of the suspected case - In Short
Clinical symptoms (fever, myalgia, bleeding from various sites)
Patient history
i. Referral from endemic area
ii. Outdoor activities (picnic, tracking, etc.) in endemic area
iii. History of tick exposure
iv.Exposure to potentially viremic domestic animal blood

Laboratory tests (low platelet and high white blood cell count, elevated AST, ALT, LDH, CPK)

Preventive measures
a. Isolate the patient
b. Inform and educate colleagues and staff
c. Use the barrier precautions

Investigations for confirmation
Serum for PCR (early in disease) and ELISA (late in disease or convalescence)
a. IgM positivity or PCR positive confirms diagnosis, IgG positivity cannot
b. Sera for differential diagnosis

Decision making for therapy
1. Ribavirin
2. Do not neglect other causes of clinical picture. Starting doxycycline or equivalent should be
3. Hematological support
a. Fresh frozen plasma to improve hemostasis
b. Thrombocyte solutions
4. Respiratory support

1. No relapse occurs after the disease. Therefore there is no need for the follow up of the cases
2. HCWs exposed to the virus should be followed up with complete blood counts and biochemical
tests for 14 days

How to prevent and Control Spread of Congo or CCHF virus?
What measures can be taken to prevent exposure to CCHF infection?

Although an inactivated, mouse brain-derived vaccine against CCHF has been developed and used on a small scale in Eastern Europe, there is no safe and effective vaccine widely available for human use.

The tick vectors are numerous and widespread and tick control with acaricides (chemicals intended to kill ticks) is only a realistic option for well-managed livestock production facilities.

Persons living in endemic areas should use personal protective measures that include avoidance of areas where tick vectors are abundant and when they are active (Spring to Fall); regular examination of clothing and skin for ticks, and their removal; and use of repellents.

Persons who work with livestock or other animals in the endemic areas can take practical measures to protect themselves.
These include the use of repellents on the skin (e.g. DEET) and clothing (e.g. permethrin) and wearing gloves or other protective clothing to prevent skin contact with infected tissue or blood.

When patients with CCHF are admitted to hospital, there is a risk of nosocomial spread of infection.
In the past, serious outbreaks have occurred in this way and it is imperative that adequate infection control measures be observed to prevent this disastrous outcome.

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.
Sharps (needles and other penetrating surgical instruments) and body wastes should be safely disposed of using appropriate decontamination procedures.

Healthcare workers are at risk of acquiring infection from sharps injuries during surgical procedures and, in the past, infection has been transmitted to surgeons operating on patients to determine the cause of the abdominal symptoms in the early stages of (at that moment undiagnosed) infection.

Healthcare workers who have had contact with tissue or blood from patients with suspected or confirmed CCHF should be followed up with daily temperature and symptom monitoring for at least 14 days after the putative exposure.

Insect repellents such as DEET can be used on the skin to preventing tick
But it should be kept in mind that the effective concentration of DEET to repel ticks
is much higher than that used for mosquitoes.
The use of DEET on small children should be avoided.
Long trousers and long-sleeved shirts should be preferred.
When being in an area of high risk, personal inspection of your clothes should be made every 2 h, and total body inspection is advised at the end of the day.
Virus transmission from the attached tick increases over time, so prompt tick
removal is important.

Can CCHFV live in vectors other than ticks, such as mosquitoes?
A: No, mosquitoes or other arthropods (other than ticks) have not been impli-
cated as vectors of CCHFV

Where do people get tick bites?
A: In case of CCHF, most of the human tick bites are from unfed adult
Hyalomma ticks.
With regard to the biology of Hyalomma marginatum group
ticks, it can be supposed that the areas frequented by hares and ground-feeding
birds are of potential risk.

Does CCHFV transmit through eating of contaminated animals?
A: No. To our knowledge no such transmission has been reported. This would
be highly due to the high acid content of our stomachs.

Can the Congo virus transmit through inhalation?
A: No, there is no report on inhalational transmission of the virus. Therefore,
the universal precautions are generally considered sufficient for the protection
of close contacts and health-care workers.

Q: How can I take a tick out if I see one attached to me?
A: Attached ticks should be taken out gently and cautiously Ticks’
mouthparts have reverse harpoon-like barbs designed to penetrate and attach to
the skin. Here is how we suggest removing an attached tick:
1. Use fine-point tweezers to grasp the tick at the place of attachment as close
to the skin as possible.
2. Gently pull the tick straight out.
3. Place the tick in a small vial labeled with your name, address, and the date.
4. Wash your hands and disinfect the bite site with isopropyl alcohol.
5. Record the date, area on your body of the tick attachment, and your general
health at the time.
6. Call your doctor to determine if treatment is warranted.
7. If possible, have the tick identified or tested by a laboratory, your local health
department, or a veterinarian.
8. Do not attempt to prick, crush, or burn the attached tick as this may cause it
to release infected fluids into your skin. Also, do not try to smother the tick
(e.g. applying petroleum jelly or nail polish).

Q: Is CCHFV a potential bioterrorism agent?
A: Yes, CCHFV is listed as a Category C bioterrorism agent by the US Centers
for Disease Control and Prevention

Reality views by sm –
Friday, January 21, 2011

Source –
World Health Org.
Book - Onder Ergonul, "Crimean-Congo Hemorrhagic Fever: A Global Perspective"
Onder Ergonul is an associate professor of Infectious Diseases and Clinical
Microbiology at the Marmara University School of Medicine in Istanbul
In total, there are 34 authors from at least 13 different countries who have contributed to this book. These authors are leading scien-tists in their fields and provide a global perspective on this global disease.

Photo Showing How To Remove Tick with Suggestions –


Renu January 21, 2011  

what a treasure of information!! would love to read something like this on cervical spondylisis.

Anonymous,  January 21, 2011  

My goodness! I felt like reading some medical encyclopedia :) Good research done, I must say :)

Rià January 21, 2011  

Thanks for passing on this crucial information. This is scary.

sm,  January 21, 2011  

I will try to write article on Cervical spondylisis.

sm,  January 21, 2011  


sm,  January 21, 2011  


chitra January 21, 2011  

really scary, so many viruses starting to appear. In the last decade we have come across lot of fancy viruses.

Usha January 21, 2011  

sm, Thanks for this very informative post on Congo CCHF Virus. I am reading for the first time and it is highly dangerous virus.
In year 2009 I was in kerala and heard about Tomato Fever...that too had life threatening symptoms but nobody even knew about it..no proper medication..no information.
It is getting scarier to learn about new viruses..knowing about viruses helps. Thanks.

Irfanuddin January 22, 2011  

you must have done lot of homework before posting this...... very detailed information !!!

sm,  January 22, 2011  


sm,  January 22, 2011  


SM January 22, 2011  

Read more than 600 pages on this topic.

Nrupen Masram January 24, 2011  

Sometimes I feel you write posts really very big, sometimes its better to break down things in parts. By the way information was really good and you way of presentation was as awesome as it also appears in other posts.

sm,  January 24, 2011  

Nrupen Masram,,
I got your point.