Para Veterinary Institute, Karor Lal Eason, (Layyah Sub Campus) University of Veterinary & Animal Sciences, Lahore
Crimean-Congo hemorrhagic fever (CCHF) is a viral haemorrhagic fever transmitted by ticks. 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 two place names resulted in the current name for the disease and the virus. It is endemic in Eurasian countries such as, Turkey, Pakistan, Afghanistan and Iran. CCHF virus is spread by the Hyalomma tick, which is found mainly on cattle and sheep. Muslim countries, in which these animals are sacrificed during Eid-Al-Adha, are among the countries where CCHF is endemic, and it has been observed that CCHF is associated with practices surrounding the Eid-al-Adha festival. The dates for Eid-Al-Adha drift 10 days earlier in each year according to Georgian calendar. In this year, the eid is occurring in summer season. Environmental hygiene and personal protection are essential parts of prevention.
Transmission
The CCHF virus is transmitted to people either by tick bites or through contact with infected animal blood or tissues during and immediately after slaughter. The majority of cases have occurred in people involved in the livestock industry, such as agricultural workers, slaughterhouse workers and veterinarians.
Human-to-human transmission can occur resulting from close contact with the blood, secretions, organs or other bodily fluids of infected persons. Hospital-acquired infections can also occur due to improper sterilization of medical equipment, reuse of needles and contamination of medical supplies.
Signs and Symptoms
If you get bitten by an infected tick, or come in close contact of an infected person or animal’s body fluids, seek immediate medical attention if you start showing the following symptoms. These symptoms appear within 1 to 3 days of the transmission and initially resemble symptoms of flu. As the disease progresses, you will most likely experience the following indications:
- High grade fever
- Stomach pain
- Diarrhea
- Myalgia (muscle aches)
- Headache
- Nausea
- Sensitivity to light
After 2 days, you may start showing additional symptoms including:
- Excessive sleepiness
- Depression
- Localized abdominal pain in the upper right side
- Rashes on the skin
- Jaundice
- Severe nosebleeds
- Uncontrolled bleeding
Congo Virus has a high fatality rate of up to 40%; thus if suspected, it needs immediate medical attention. If diagnosed late, these symptoms are difficult to control and can lead to organ failure and eventually death. Hence, early intervention is crucial.
Treatment
General supportive care with treatment of symptoms is the main approach to managing CCHF in people.
The antiviral drug ribavirin has been used to treat CCHF infection with apparent benefit. Both oral and intravenous formulations seem to be effective. In severe cases, consult to veterinary doctor.
Prevention and Control
It is difficult to prevent or control CCHF infection in animals and ticks as the tick-animal-tick cycle usually goes unnoticed and the infection in domestic animals is usually not apparent. Furthermore, the tick vectors are numerous and widespread, so tick control with acaricides (chemicals intended to kill ticks) is only a realistic option for well-managed livestock production facilities. There are no vaccines available for use in animals.
In the absence of a vaccine, the only way to reduce infection in people is by raising awareness of the risk factors and educating people about the measures they can take to reduce exposure to the virus.
When buying the sacrificial animals or caring for animals
- Inspect the animal body to check for ticks each day.
- Do not touch or crush the tick with your bare hands.
- Do not try to remove the tick with your fingers.
- Wear light colored, full sleeve clothes and shoes with socks.
- Apply an insect repellent on the exposed area of body.
- Must take precautions against accidental exposure.
- Should take precautions to prevent serious injury to themselves and others.
- Take a shower and change your clothes as soon as you return home.