Explained: What is the nose-bleed fever spreading in Iraq? Do we have vaccines?

Baghdad, Jun 02: A viral 'nose-bleed' infection originally known as Crimean-Congo hemorrhagic fever, spread by ticks is on the rise and has already killed 19 people, the World Health Organisation (WHO) has warned. The disease is causing severe hemorrhaging among patients.

Since January,a Around 212 cases of Crimean-Congo Hemorrhagic Fever (CCHF) have been reported, 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.

What is 'Nose-bleed fever' or Crimean-Congo hemorrhagic fever?

According to the WHO, 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.

Symptoms

Following infection by a tick bite, the incubation period of Crimean-Congo haemorrhagic fever (CCHF) is usually one to three days, with a maximum of nine days. Following contact with infected blood or tissues, the incubation period is usually five to six days, with a maximum of 13 days.

Onset of symptoms is sudden, with fever, muscle ache, dizziness, neck pain, backache, headache, sore eyes and photophobia (sensitivity to light). There may be nausea, vomiting, diarrhoea, abdominal pain and sore throat early on, followed by sharp mood swings and confusion. After two to four days, the agitation may be replaced by sleepiness, depression and lassitude, and the abdominal pain may localize to the upper right quadrant, with detectable hepatomegaly (liver enlargement).

Other clinical signs include tachycardia (fast heart rate), lymphadenopathy (enlarged lymph nodes), and a petechial rash (a rash caused by bleeding into the skin) on internal mucosal surfaces, such as in the mouth and throat, and on the skin. The petechiae may give way to larger rashes called ecchymoses, and other haemorrhagic phenomena. There is usually evidence of hepatitis, and severely ill patients may experience rapid kidney deterioration, sudden liver failure or pulmonary failure after the fifth day of illness.

Treatment

General supportive care with treatment of symptoms is the main approach to managing Crimean-Congo haemorrhagic fever (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.

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

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 widely available for human or animal use. 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.