Climate Change may be behind recent rise in Monkeypox cases

In a world that has been reeling under a pandemic, any new outbreak of transmissible diseases sends shockwaves across the nations. Monkeypox has been one such recent shockwave. 

The World Health Organisation (WHO) has labelled this rapidly spreading outbreak as a Public Health Emergency of Global Concern – its highest level of alert. WHO says that this is the first time that many monkeypox cases and clusters have been reported concurrently in non-endemic and endemic countries in widely disparate geographical areas. Some scientists and experts have stated that this sudden spread is largely but not only due to factors arising out of Climate Change. 

WHAT IS MONKEYPOX?

An orthopoxvirus that causes a disease with symptoms similar, but less severe, to the now eradicated smallpox, monkeypox occurs in countries of central and west Africa.

The WHO website states that two distinct clades are identified: the west African clade and the Congo Basin clade, also known as the central African clade.

HOW IS MONKEYPOX TRANSMITTED?

A Zoonosis, Monkeypox is a disease that is transmitted from animals to humans. The cases that were usually recorded earlier were close to tropical rainforests where there are animals that carry the virus.

IS MONKEYPOX TRANSMITTED VIA HUMAN CONTACT?

Human-to-human transmission of monkeypox, though limited, happens through contact with bodily fluids, lesions on the skin or on internal mucosal surfaces, such as in the mouth or throat, respiratory droplets and contaminated objects. 

CLIMATE CHANGE AND INCREASE OF INFECTIOUS DISEASES

Many wild animals are migrating in search of better habitats owing to the steady rise in temperatures worldwide. Some of those animals, infected with various diseases, end up in regions near human populations thus leading to a rise in chances of humans contracting zoonotic diseases- something that the human body is usually not equipped to deal with. Many of these diseases or viruses travel to humans through means like ticks or mosquitos, which are also reportedly increasing due to climate change. There is also the chance of bats and birds spreading viruses amongst the human population.  

CLIMATE STRESS AND ANIMAL BEHAVIOUR

Recently, Dr. Mike Ryan, WHO’s executive director for health emergencies, said at a WHO Discussion for Global Health ‘There is definitely ecological pressure in the system. Animals are changing their behaviour. Humans are changing their behaviour.’ Dr Ryan referred to the Director General who spoke earlier in the same meeting about climate stress and drought stress as well. ‘That (climate stress) is not just changing human behaviour, it’s changing animal behaviour. It’s changing the range of animals. It’s changing food-seeking behaviour and many other things,’ he added.

WHAT DO STUDIES SAY?

‘Climate change is predicted to result in shifts in the incidence and prevalence of infectious diseases and may impose health risks on human populations in previously unexposed regions. As a result, the incidence of a variety of viruses is predicted to increase,’ said a study, ‘Pathogen-Host Associations and Predicted Range Shifts of Human Monkeypox in Response to Climate Change in Central Africa’ published back in 2013.  

A peer-reviewed study titled ‘Climate change increases cross-species viral transmission risk’ published in April 2022 states that the risk of cross-species transmission is on the rise due to the changes in climate and due to human settlement in areas that are habitats of animals which were once geographically isolated.   

The study also finds that this ‘ecological transition may already be underway, and holding warming under 2 °C within the twenty-first century will not reduce future viral sharing.’ It stresses the need to pair viral surveillance and discovery efforts with biodiversity surveys tracking the range shifts of species, especially in tropical regions that contain the most zoonoses and are experiencing rapid warming.

The Boston Globe, in June 2022, published an article on the same study linking such diseases and climate change. The article states that scientists don’t expect monkeypox to ravage the world the way that COVID-19 did. ‘But in the future, other diseases from animals could. In fact, nearly every pandemic of the past 100 years — from the Spanish flu to COVID-19 — is thought to have been the result of pathogens spreading from animals to people, said Aaron Bernstein, interim director of the Center for Climate, Health, and the Global Environment at Harvard’s T.H. Chan School of Public Health,’ the article quoted.