Wednesday, 11 January 2017

Climate change impacts on Human health


Climate change is affecting human health patterns

The occurrence of extreme weather events is increasing as a result of climate change. Extreme heat events, floods and precipitation variability are likely to injure people or even cause deaths. But certainly extreme weather events or changing climate patterns can affect a further crucial aspect – human health. Accompanied by a longer duration, frequent occurrences, and major impacts of events, diseases are more likely to increase and spread. Given the fact that appearance of diseases is linked to a changing environment pattern, it is obvious that “human health has always been influenced by climate change and weather” (U.S. Global Change Research Program, 2016).

Figure 1: Changing patterns of various factors due to temperature rises. Source: Reyer C. et al., 2015.

Examining figure 1, it is evident, that the occurrence of extreme events and diseases, are rising along with the temperature. The impact on health is intrinsically related to growing temperature extremes and as well as monitored factors.

Why is human health vulnerable to climate change?

There are direct and indirect effects of climate change operating on our environment (ClimDev-Africa, 2013). As we perceive the consequences of natural disasters, rather unnoticed indirect effects, such as ecological change, land use change, air pollution and water quality can affect human health. WHO reports that, since the 1960s, the number of weather-related natural diseases has increased by more that 300% (WHO, 2016).

The changing climate is affecting various approaches for spread diseases:

Food borne diseases:
It is estimated that 1.7 million deaths in Africa are caused by malnutrition every year (ClimDev-Africa, 2013). Extreme weather events are likely to exacerbate the food supply. Storms or heavy rain events can destroy crops and lead to crop failure or interrupt the transportation. The lack of nutrition due to climate change is increasing and evokes further victims of malnutrition.

Water borne diseases:
Diseases are caused by pathogenic microorganisms, which are transmitted by water. An extreme flooding event can transmit these microorganisms into human settlements, as they are flooded, and occur certain diseases, such as cholera or dysentery. This effect is intensifying respectively to a growing risk of flood events (McMichael et al., 2006).

Vector borne diseases:
Rising temperature or changing rain patterns can alter the occurrence of vector borne diseases, transmitted by insects like mosquitoes, flies or ticks. Climate sensitive diseases like malaria increase due to inadequate sanitation or flooding (McMichael et al., 2006).

Respiratory diseases:
Greenhouse gases affect our climate and are responsible for global warming. Due to this they can affect human health. The timing of pollen is changing and air particles of pollution are ingested to our lugs. This can cause asthma attacks or allergic reactions. Children and elderly people suffer in particular, as they are more likely to be affected (McMichael et al., 2006).
Figure 2: Distribution on mean temperature. Source: McMichael et al., 2006.

Considering figure 2, the originally baseline of the mean temperature, ensuring from the scenarios with both increasing mean temperature and variability, is postponed in direction of the higher temperatures. This leads to an increasing occurrence of direct or indirect diseases. The mean temperature is rising and the risk of extreme events that can cause diseases is growing.

Adaptations to prevent further negative developments

Impacts on human health can be devastating. It is essential to support those who are affected by human health impacts. Organisation such as WHO draft a work plan to undermine health impacts of climate change. For instance:

-       Partnerships: Partner agencies are necessary to support a proper heath system and to encourage the population to participate in such a system (WHO, 2016).
-       Awareness raising: One of the most important approaches is to raise awareness, as people then start acting to change their behaviour, if they believe in the alteration of their circumstances. It is required to provide information of climate change and its threats to convince people to change their behaviour (WHO, 2016).
-       Science and evidence: If we know how and why patterns are changing, we have the ability to alter them. A science based evidence helps us to understand these questions (WHO, 2016).
-       Support for implementation of the public health response to climate change: Most affected countries are not able to improve their health systems. Therefore, they need organisations to assist them by building up a state capacity to reduce their vulnerability (WHO, 2016).