“Quo Vadis, Ebola?”: Health Impacts of Climate Change

To immediately conclude that the renewed attack of the ebola virus is climate change related is equally irresponsible to saying that it has nothing to do with it. It is true that not much is conclusive regarding the effect of climate change in the development and spread of the virus but, just like other agents of illnesses, the connection is very logical and cannot just be simply ignored.

The World Health Organization had listed the following key facts on Ebola Virus Disease:

1. Ebola virus disease (EVD), formerly known as Ebola hemorrhagic fever, is a severe, often fatal illness in humans.
2. EVD outbreaks have a case fatality rate of up to 90%.
3. EVD outbreaks occur primarily in remote villages in Central and West Africa, near tropical rainforests.
4. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.
5. Fruit bats of the Pteropodidae family are considered to be the natural host of the Ebola virus.
6. Severely ill patients require intensive supportive care. No licensed specific treatment or vaccine is available for use in people or animals.

Facts Nos. 3, 4, and 5 are climate change related in varying degrees.

The WHO had made and published a lot of studies assessing the impacts of climate change on health. Particularly, the studies involve vector borne diseases (VBD). VBDs are transmitted by the bites of infected mosquitoes and other insects (vectors). Their incidence is particularly dependent on climatic factors because:

1. Insects have no internal control over their physiological temperatures and the ambient temperature determines their reproduction rate, biting behavior and survival: their distribution may expand as the earth warms.
2. Humidity and availability of water for breeding are also determinants of vectors’ distribution, longevity and behavior.
3. The incubation period of pathogens inside vectors is temperature-dependent (and tends to decrease at warmer temperatures).
4. Human behavior is likely to be affected by climate change which will alter our interaction with vectors and the diseases they carry.

Mistakes had been committed by neglecting the impacts of climate change on health starting the 1990’s. However, present climate change related deaths cannot anymore be ignored. Much more, scientists are concerned about further dangers and deaths due to climate change.

Here are some figures:

1. The Global Humanitarian Forum (GHF) published a report estimating that 315,000 people die due to climate change every year, and they predict this will rise to half a million by the year 2030. [3] While such estimates of direct deaths remain low relative to the size of the global population, about 310 million people are expected to have suffered ill health because of climate change by 2030.
2. Nine out of ten of these people will be in developing countries and the number of healthy years of life lost to environmental change, including climate change, is set to be 500 times higher in Africa than Europe
3. Heat waves can kill thousands—in August 2003, Europe’s summer was about 3.5 degrees Celsius above average and an estimated 45,000 people died over two weeks.
4. By 2080, up to 320 million more people could be affected by malaria because of these new transmission zones. Worryingly, the disease would then also be spreading to people whose immune systems may never have been exposed to malaria, and who may be more vulnerable as a result.
5. Some scientists estimate that by 2080, six billion people will be at risk of dengue, compared with 3.5 if the climate does not change. If the global population grows to about 10 or 11 billion by then, as some estimates suggest, over half the planet could be at risk.
6. Schistosomiasis, a parasitic disease transmitted by aquatic snails, also seems to be affected by climate. In China, the latitudinal threshold beyond which temperatures were too cold for the snail to live has moved northwards, putting nearly 21 million more people at risk of the disease.

Climate is without doubt a factor in the way of life of all living things. That is basic. Living things thrive on a particular climate. If it becomes unbearable, they try to adapt to it or find another place where climate is favorable. Migration complicates the matter of disease control and prevention. Even now, countries are already securing their borders and other places of entry. Intensive scrutiny is being implemented. But we know how minute and difficult to handle these agents of destruction are. And we are aware that there are people who are unconscious and insensible regarding these things. Outbreaks are always a probability.

Essentially, science had proven time and again that different strains develop. In these developments, climate change is a factor. We may not know the details of the processes, but we certainly know something is happening. We can just pray that it will be for the good. But we cannot deny it can be for the worse. In this case, it will not be harmful to be conservative, i.e. to assume the relation and make the necessary precautions.

“Climate change is not going to invent any new diseases; it’s going to make controlling existing diseases harder. We’ve been describing the links between climate change and health for quite a long time,” says Diarmid Campbell-Lendrum, head of the climate change team at the World Health Organization’s headquarters.

Scientists admit that vector-borne diseases are among the most complex and vexing illnesses to manage due to a lot of factors involved. These factors include host resistance, the environment, urbanization and the pathogens themselves. By virtue of these, it would be a big mistake not to take into account every single thing which maybe related to the matter, one way or the other. And with the added effects of warming weather and shifting precipitation, ongoing disease-management efforts are becoming more complicated.