Climate Change and Human Health
Den
e e er Cases Philippines 1992 2005
40
35
35
30
29 9
25
25
22 8
20
15
1
14
10
5
52
199
92 8
5
1995
4
1994
5
14
12 8
2005
2004
2003
2002
2001
2000
1999
1998
199
1993
1992
0
No of Cases ( ho san s)
Figure 4. Relation of Dengue Cases and Temperature
Change in the Philippines. Adapted from Perez, 2009. 26
alaria Cases in the Philippines 1995 2005
3 000
2 500
2 000
24
1 883
1 500
1 483
greatest contribution to global warming.28 Carbon dioxide
comes from combustion of fossil fuel and solid waste,
cement manufacturing and steel and iron production.
Methane comes from landfills, enteric fermentation, and coal
mining. Nitrous oxide comes primarily from agricultural soil
and mobile combustion. Examples of agricultural activities
are applications of nitrogenous fertilizers, enteric
fermentation, manure management, agricultural soil
management, and field burning.28
Link between Climate Change, Environmental Pollutants,
and Incidence of Diseases
Climate change also has a significant impact on air
pollutants. Air-borne pollutants such as carbon dioxide,
carbon monoxide, methane, nitrogen oxide, and sulfur
dioxide contribute to the warming of global temperature. 29
Warmer temperatures increase the presence of secondary air
pollutants such as ozone and particulates in the atmosphere.
According to Martens et al.,19 air pollutants can aggravate
allergic and cardio-respiratory illnesses.2
Table 8 presents a study of the Department of Health
(DOH) on the impact of air pollution to the public health of
Metro Manila. The data show the effect of air pollutants to
human health such as respiratory and cardiovascular diseases.
22 3
1
1 24
13 8
2
1 501
1 89
1 589
Table 8. Air Pollution Impacts on Public Health of Metro
Manila30
Morbidity
10,000 excess cases of acute bronchitis
1 000
500
300 excess cases of asthma
1 5
Mortality
40-200 persons due to
cardiovascular causes
300-330 persons due to
respiratory causes
9 excess cases of chronic bronchitis
No of Cases
Figure 5. Relation of Malaria Cases and Temperature
Change in the Philippines. Adapted from Perez, 2009.26
Discussion
At the advent of industrial revolution, increasing fossil
fuel use, deforestation, irrigated agriculture, animal
husbandry, among others have been associated with the
increase in the concentration of atmospheric greenhouse
gases (Haines, et al, 2000), resulting in an unprecedented
variability of climate.27 Indeed, the global climate
temperature is linked to human activities.8
The largest contributor to build up of greenhouse gases
comes from human-generated activities such as land use
planning, transportation systems and infrastructure,
building construction and operation. The greenhouse gases
that are produced from various agricultural and industrial
activities include carbon dioxide, methane, and nitrous
oxide. Of the three main gases, carbon dioxide has the
96 ACTA MEDICA PHILIPPINA
Climate change can affect health in several pathways.
These pathways can be through 1) increased frequency and
intensity of heat waves; 2) increased floods and droughts; 3)
changes in the distribution of vector-borne diseases; and 4)
risks of disasters and malnutrition.17 There are several diseases
that can be impacted by climate change. These are insect and
rodent borne diseases (e.g., dengue, leptospirosis, and
malaria), water-borne diseases (e.g., schistosomiasis, cholera),
food-borne diseases (e.g., diarrhoeal diseases and typhoid),
respiratory diseases (e.g., asthma, bronchitis, and respiratory
allergies and infections), and heat-related illnesses (e.g.,
sunstroke, sunburn, heat stress or exhaustion, dehydration).13
The study of Ebi in 2008 showed the correlation of
various diseases with indicators of climate change. His study
was conducted in five provinces and one city in the
Philippines.31 The study showed that diarrhea and malaria
are most affected by climate change while diseases such as
tuberculosis, meningococcemia, tetanus, chicken pox,
influenza, bronchitis, pneumonia, nutritional deficiencies,
malignant neoplasms (cancer) and mumps had the higher
percent correlation with the climate change. In another study,
VOL. 50 NO. 2 2016