The impact of out-door air pollution on respiratory health and stunting in school children in Nairobi Kenya
Abstract
Introduction: Globally urban air pollution is estimated to be responsible for 800,000
premature deaths each year. Acute respiratory infections are ranked fourth in the share of
disease burden in Sub-Saharan Africa accounting for 7% of total deaths. Air pollution is a
nuisance to industry mostly concentrated in urban centers where majority of the people live.
Nairobi was reported to be having high levels of particulate matter SPMlO (239-126m3
)
higher than WHO acceptable level of 150ug/m3.
Objective: The main objective of the study was to assess the impact of air pollution on the
respiratory symptoms among school going children in Nairobi. A questionnaire was sent out
to parents using the children. Children in kindergarten were examined for signs of
respiratory infection while those attending primary schools were examined for height, weight
and peak flow measurements. Only children whose parents gave a written consent were
allowed to participate.
Study Design: This was a comparative ecological study intended to find out whether a
difference existed in episodes of respiratory symptoms, peak flow reading, BM! and stunting
among children in two residential areas. One of the study areas was proximal to industrial
area (South C) while the other was 10 kms away that is (Ngummo) estate in Nairobi.
Setting and Time Frame: Seven schools were randomly selected. Data collection took
place from January 2004 through to October 2004.
Methods: Data was obtained by making observation and self administered questionnaires.
The respondents of the questionnaires were children's parents while the principal
investigator carried out the clinical observation and other measurements.
Results: A total of 602 cases were selected, 303 were from Ngummo residential estate
while 299 were from South C estate. Out of these, 306 were from primary schools while
296 were from pre-primary schools. The mean age was 7.6 years.
The children came from similar socio economic class, allergic reaction, cooking fuel and
smoking patterns were also similar. Response rate was 85%. Reported cough was the
highest reported with an overall morbidity at 39.5% and the least reported was high
temperature. The most observed symptom was inflammed throat at 52.7% and the least
observed was sneezing 0.7%. The results showed more cases of respiratory infection signs
in South C compared to Ngummo. For example, observed inflammed throat and blocked
nose in kindergarten child were statistically significant respectively (x2=9.32,df= l,p= 0.002
and X2=10.4l,df= l,p=O.OOl) using chi test of significance. The reported symptoms were not
statistically significant probably due to inaccurate reported information. Majority of cases
recorded abnormal peak flow measurements may be due to poor technique in handling the
gadget or the table used to compare was not applicable to Kenyan and African children in
general. Abnormal peak flow comparison was statistically significant
(x2=43.506,df=28,p=0.03l). Body Mass Index showed statistically significant with low 8MI
recorded in a more polluted area. Multiple regression analysis confirmed the exposed zone,
assessed as residence, as a risk factor for observed blocked nose (Wald's
stat=4.l47,p=0.053), inflammed throat (Wald's stat=9.270,p=0.005), and reported sore
throat (Wald's stat=4.205,p=0.040).
Conclusion: Proximal human habitation to industrial setup was found to be a risk factor in
exacerbation of respiratory infections
Recommendation: The result suggests the need for action in regulating air pollution in the
city of Nairobi or else there will be continued increase in disease burden due to air pollution
related illnesses(respiratory symptoms) as it is the case in cities of developed countries.
Citation
Masters Degree in Public Health University of Nairobi, 2007Publisher
University of Nairobi, School of Nursing Sciences