Why monkeypox is less dangerous than COVID-19 despite higher fatality rate

The monkeypox virus is less dangerous than COVID-19 despite it having a higher fatality rate, a biochemistry expert says.

The World Health Organization confirmed there are currently 92 cases globally with another 28 suspected infections in 12 countries. 

The UN agency said it expects to identify more cases of monkeypox as it expands surveillance in countries where the disease is not typically found and will provide further guidance and recommendations in the coming days. 

Otago University biochemistry professor Kurt Krause told AM on Monday that monkeypox - which is a relative of chickenpox and smallpox - traditionally only sees small outbreaks.

"Monkeypox can be serious but generally speaking, the outbreaks that occur involve a few hundred people and they fizzle out because the virus isn't transmitted that readily from one person to another," Krause told AM host Ryan Bridge. 

Krause said the strain of monkeypox believed to be circulating around the world is from west Africa and has a fatality rate of around 1 percent.

"It looks like the cases are the west African strain, so that would be in the lower group, but it's so much different from coronavirus in that it's so much less transmissable and once you get to the pox stage, it's quite apparent," Krause told AM.

"The COVID-19 fatality rate is about a third to half of a percent depending on which strain. Omicron is a little bit less than that, Delta was about that rate."

Krause said the big difference between the two viruses is that monkeypox is "dramatically less' contagious" than COVID-19. 

He said the R-value for monkeypox has traditionally been less than one, meaning each existing infection causes less than one new infection.

Compare that to COVID-19, and in February, New Zealand had the highest R-value in the world of 3.74.

Otago University biochemistry professor Kurt Krause
Otago University biochemistry professor Kurt Krause Photo credit: AM

Australia reported its first probable case of monkeypox from a recently returned traveller from Europe, but Krause thinks Kiwis shouldn't be too worried about the virus. 

"I think we are going to be okay. We need to keep our eye on it and I think it's possible New Zealand could get one or two cases, but it's not likely to spread," Krause said. 

He said if someone catches monkeypox, they would need to isolate, let it scab over and dry out, which takes about 2-3 weeks and then they'll not be contagious. 

"If you have contact with somebody who's got pox lesions or contact with the material they have contaminated or respiratory secretions, that is how you get it. It's not transmitted by aerosol like Coronavirus is."  

Monkeypox is a virus that can cause symptoms including fever, aches and presents with a distinctive bumpy rash.

Watch the full interview with Kurt Krause above.