Coronavirus tops the WHO concern list

While the immediate dangers of COVID-19 do appear to be subsiding, epidemiologists at the WHO have identified it among nine viruses that still have the potential to explode into the next public health emergency.

Since 2017, the organization has maintained a list of diseases that pose the greatest potential threat to humanity and require further research to ensure we are able to contain and combat them.

Coronavirus remains at the top of the list, with the other viruses of concern listed as follows:

Crimean-Congo haemorrhagic fever

An endemic disease frequently found in Africa, the Balkans, the Middle East and Asia, Crimean-Congo hemorrhagic fever is spread when people are bitten by infected ticks or encounter sick livestock.

The resulting condition can damage the body’s internal organs and cardiovascular system, and can cause severe bleeding.

The disease has a fatality rate of 10 to 40 per cent. A vaccine is licensed in Bulgaria, but has not been approved anywhere else as yet.

Ebola and Marburg

Bats and primates carry both diseases, part of the filovirus family, which also cause hemorrhagic fevers.

Once a human has been infected, they commonly spread the viruses to others through their bodily fluids, through direct contact, or through contact with contaminated surfaces in unsterilized settings.

They typically have a fatality rate of 50 per cent, although this has varied from 25 to 90 per cent in previous outbreaks.

Vaccines have been used for Ebola in Guinea and the Democratic Republic of Congo but are not widely approved.

Lassa fever

Endemic in West Africa, this disease is spread through the urine and faeces of rats and rodents. Humans who contract it can then pass it on through their own excreta or blood or through sexual contact.

Lassa fever is believed to pose a particular danger to pregnant women in the third trimester of pregnancy and can also cause deafness in patients.

The fatality rate is low at 1 per cent, although this rises to 15 per cent in cases where sufferers’ conditions are serious enough to result in hospitalisation. Ribavirin has been used to treat it but there is no vaccine.

MERS

Middle East Respiratory Syndrome is a deep infection of the respiratory tract and is native to the region, where it is carried by camels.

Once contracted by a human, it can be passed on to others by close contact.

Its fatality rate is high at 35 per cent and it has been diagnosed in 27 countries since 2012, according to the WHO, but there is still no vaccine.

Nipah virus

This is recurrent in Asia and carried by fruit bats, as well as domestic animals such as pigs, horses, cats and dogs. It can be transmitted to humans by these carriers, as well as from person to person.

It can cause swelling of the brain (encephalitis), has a 40-70 per cent fatality rate and is currently without a vaccine.

Rift Valley fever

A disease of the blood carried by mosquitoes, who pass it on by biting humans or livestock such as cows, sheep, goats, buffalo and camels, Rift Valley fever has spread from Africa to Saudi Arabia and Yemen.

Although the fatality rate is less than 1 per cent and Rift Valley is mild for most people, around 8 to 10 per cent of patients develop severe symptoms, including eye lesions, encephalitis and hemorrhagic fever.

A vaccine has been developed but is not yet licensed anywhere.

Zika virus

Another disease spread by mosquito bites, which can infect the blood and be transmitted through sex, Zika is rarely fatal but can cause severe brain defects in foetuses and has been known to cause miscarriages and stillbirth.

There is, at present, no vaccine.

‘Disease X’

A space is reserved on the list for an as-yet-unknown virus that could arise in future to cause us problems.

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