Crimean-Congo Hemorrhagic Fever in Iraq - World Health Organization

Outbreak at a glance

Between 1 January to 22 May 2022, the health authorities of the Republic of Iraq notified WHO of 212 cases of Crimean-Congo Hemorrhagic Fever (CCHF), of which 115 (54%) were suspected and 97 (46%) laboratory-confirmed; there were 27 deaths, 14 in suspected cases and 13 in laboratory confirmed cases. The number of cases reported in the first five months of 2022 is much higher than that reported in 2021, when 33 laboratory confirmed cases were recorded. Cases have been reported in several areas (governorates) in Iraq and the outbreak may pose additional pressure to an already over-stretched health care system.

Outbreak description

Between 1 January and 22 May 2022, 212 cases of CCHF have been reported to the WHO from the Iraqi health authorities of which 169 (80%) were reported in April and May alone. Of the 212 cases, 115 were suspected and 97 laboratory confirmed.  Twenty seven deaths occurred overall, of which 13 were in laboratory confirmed cases [case fatality ratio (CFR) 13%; 13/97].

The Iraq Central Public Health Laboratory confirmed the cases by polymerase chain reaction (PCR).

Among confirmed cases, most had direct contact with animals, and were livestock breeders or butchers. Just over half of the confirmed cases were 15 to 44 years old (n=52; 54%) and of male gender (n=60; 62%).

Nearly 50% of confirmed cases (n=47; 48%) were reported in Thiqar governorate, southeast Iraq, and the remainder of cases were reported from 12 different governorates; Missan (13), Muthanna (7), Wassit (6), Diwaniya (4), Baghdad Karkh (4), Kirkuk (3), Basrah (3), Najaf (3), Nineveh (3), Baghdad-Rusafa (2), Babylon (1) and Karbala (1) (Figure 1).

Figure 1. Distribution of laboratory confirmed cases of Crimean-Congo Hemorrhagic Fever by governorate, Iraq, 1 January to 22 May 2022 (n=97).

Epidemiology of the disease

CCHF is a viral tick-borne disease that is transmitted to humans by bites of infected ticks, and by direct contact with blood or tissues from infected humans and livestock. CCHF is endemic in Africa, the Balkans, the Middle East and Asian countries south of the 50th parallel north – the geographical limit of the principal tick vector.

Iraq is one of the eastern Mediterranean countries where CCHF is endemic. CCHF has been reported in Iraq since 1979 when the disease was first diagnosed in ten patients. Since then, six cases were reported between 1989 and 2009; 11 cases in 2010; three fatal cases were reported in 2018; and more recently 33 confirmed cases including 13 deaths (CFR 39%) were reported in 2021.

Sheep and cattle husbandry are very common in Iraq. Studies have shown that these animals are regularly infested with tick species, mainly Hylomma species, the principal vector of CCHF.

Human cases of CCHF are mainly treated with general supportive care. The antiviral drug ribavirin, both oral and intravenous formulations, has been used to treat CCHF infection. However, no evidence from randomized clinical trials has demonstrated the effectiveness of ribavirin for treating CCHF. There is currently no vaccine available for either people or animals.

Public health response

Health authorities conducted the following multidisciplinary outbreak response:

• Health authorities deployed an epidemiological investigation team to Thiqar governorate. The teams comprised fellows from the Iraq Field Epidemiology Training Program and staff from the Communicable Disease Control section of the Ministry of Health (MoH). The epidemiology team conducted an outbreak investigation, which included a house-to-house visit of the reported cases and contact tracing. They also conducted entomological investigation for disease vectors, which included the collection and classification of ticks from each site of reported suspected cases.
• The MoH vector control team sprayed indoor and outdoor acaricides in affected areas and the veterinary hospital treated domestic animals with acaricides in affected areas.
• Teams from the MoH and the Ministry of Agriculture printed Information, Education, and Communication materials which outlined prevention and control measures for CCHF. They shared the materials with case contacts and the local community, especially butchers and animal barns owners.

WHO is collaborating with the MoH on the availability of diagnostic kits and genomic sequencing. In addition, WHO and the Iraqi health authorities are holding regular teleconferences to assess and provide guidance for the outbreak response.

WHO risk assessment

Thiqar governorate is divided into rural (42% of the governorate) and urban (58%) areas, where livestock farming of sheep, goats, cattle, camels, and buffaloes is an important source of livelihood, especially for the rural population. Subsistent farming is common in villages where animal barns are located near houses and all family members take care of domestic animals. In these settings, CCHF may be transmitted from domestic animals to humans.

There is an increased risk of further spread of CCHF within Iraq due to the upcoming religious holiday, Eid al-Adha in July, because more camels, cows, and sheep will be slaughtered during that period. Additionally, international cross-border transmission cannot be ruled out given the increased population movement and possible animal exportation associated with the holiday. During Ramadan, which took place in March and April 2022, the number of CCHF cases steadily increased, and the geographical spread of the disease expanded to more governorates.

WHO advice

WHO continues to emphasize the importance of maintaining strong CCHF surveillance, diagnostic capacity, and outbreak response activities by all Member States.

WHO also recommends reducing the risk of tick-to-human, animal-to-human, and human-to-human transmission by (i) enforcing relevant preventive measures during slaughtering, butchering and culling procedures, (ii) quarantining animals before they enter slaughterhouses or routinely treat animals with pesticides two weeks prior to slaughtering them, and (iii) ensuring that health care workers implement infection prevention control measures when taking care of CCHF cases or other cases presenting with haemorrhagic fever.

WHO does not recommend any restriction on travel and trade to Iraq based on the information that is currently available.

Further information

• WHO Crimean-Congo Hemorrhagic Fever fact sheet: https://www.who.int/news-room/fact-sheets/detail/crimean-congo-haemorrhagic-fever#:~:text=Key%20facts,from%20ticks%20and%20livestock%20animals.
• Inter-Agency information and analysis unit supported by OCHA and UNAMI, May 2022. Accessible at: http://www.iauiraq.org/gp/print/GP-Thi-Qar.asp
• NGO Coordination committee for Iraq, December 2015. Available at: https://www.ncciraq.org/images/infobygov/NCCI_ThiQar_Governorate_Profile.pdf
• Food and Agriculture Organization (FAO) Agriculture sector note for Iraq prepared under the FAO/World Bank Cooperative Programme, 2012. Available at: https://www.fao.org/3/i2877e/i2877e.pdf
• Hasson RH. Tick distribution and infestation among sheep and cattle in Baghdad's south suburb. مجلة الكوفة للعلوم الطبية البيطرية| Kufa Journal For Veterinary Medical Sciences. 2012 Jun 15;3(1).
• Consensus report: Preventive measures for Crimean-Congo Hemorrhagic Fever during Eid-al-Adha festival https://www.ijidonline.com/article/S1201-9712(15)00167-8/pdf 
• Al-Tikriti SK, Al-Ani F, Jurji FJ, Tantawi H, Al-Moslih M, Al-Janabi N, Mahmud MI, Al-Bana A, Habib H, Al-Munthri H, Al-Janabi S. Congo/Crimean haemorrhagic fever in Iraq. Bulletin of the World Health Organization. 1981;59(1):85.

Citable reference: World Health Organization (1 June 2022). Disease Outbreak News; Crimean-Congo Haemorrhagic Fever in Iraq. Available at: https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON386