A virus with a fatality rate of up to 30 per cent is killing unprecedented numbers of people in Iraq.
Crimean-Congo haemorrhagic fever was first documented there in 1979 and historically there have been only a handful of cases each year.
But infections caused by the tick-borne virus have soared since the start of this year, with more than 100 recorded so far.
The cause of the increase is not fully understood but some experts think global warming could have had a hand in it.
The National explains everything you need to know about the virus.
What is Crimean-Congo haemorrhagic fever?
It is a tick-borne virus, first discovered in Crimea in 1944, and subsequently named Crimean haemorrhagic fever.
It was later also discovered in the Congo, resulting in the current name.
It is the most widespread type of viral tick-transmitted haemorrhagic fever, according to the European Centre for Disease Prevention and Control, and it can be up to 30 per cent fatal for those hospitalised.
It is called a haemorrhagic fever as infected people can experience fever and severe bleeding, among other symptoms.
The virus is transmitted to people by tick bites or through contact with infected animal blood or tissue during and immediately after slaughter.
There is currently no approved vaccine for this disease.
What are the symptoms?
The incubation period is around three to seven days, less if contracted via tick bite or needle injury as opposed to coming into contact with infected blood.
The majority of CCHF cases, more than 80 per cent, are asymptomatic or mild.
More severe symptoms begin suddenly, with a headache, high fever, back pain, joint pain, stomach pain, and vomiting.
Red eyes, a flushed face, a red throat, and petechiae (red spots) on the palate are also common, according to the US Centres for Disease Control and Prevention. Jaundice can occur, in addition to changes in mood and sensory perception.
On about the fourth day of the illness, large areas of severe bruising develop, along with heavy nosebleeds and uncontrolled bleeding at injection sites. This phase lasts for about two weeks.
Children usually exhibit milder symptoms.
Where is it found?
Sporadic outbreaks of the disease have been reported in parts of Asia and Africa, while in European cases have so far been restricted to the Balkan region, Spain, Russia and Turkey.
Around three billion people are at risk globally but in previous years, the number of cases in Iraq could be counted on ‘one hand’. Numbers have rocketed this year, particularly in Dhi Qar, a poor farming region in the south, which accounts for nearly half of Iraq's cases.
The country has so far this year recorded 111 CCHF cases and 19 deaths.
The surge has shocked officials, because numbers far exceed recorded cases in the 43 years since the virus was first documented in Iraq in 1979.
Why have there been so many cases this year?
The cause has not been identified, but the WHO's representative in Iraq, Ahmed Zouiten, said there were several hypotheses.
They include the absence of livestock-spraying campaigns during Covid in 2020 and 2021, resulting in the increased spread of ticks.
“Very cautiously, we attribute part of this outbreak to global warming, which has lengthened the period of multiplication of ticks,” Mr Zouiten said.
However, mortality appears to be declining after Iraq mounted a pesticide spraying campaign, he said, while new hospital treatments had shown “good results”.