Study of Weather Related Respiratory Diseases in Eco-climatic Zones

We study the temporal pattern of selected respiratory diseases and the influence of specific weather parameters on their morbidity in two eco-climatic zones in Nigeria for the period 1996-2006. Out of 2,056 and 2,647 cases of respiratory diseases (bronchial asthma, bronchopneumonia, lobar pneumonia, bronchiolitis, cardiac asthma, pulmonary tuberculosis, sinusitis, tonsillitis and upper respiratory tract infection) reported in Humid- forest (Ile-Ife) and Derived-savanna (Ilorin), respectively, 60% and 48% for each region respectively occurred in subjects of age less than ten years. Whereas, for patients aged 80 years and above it accounted for 1.2% and 1.7% in respective zones. There is a significant (p< 0.01) variation in the morbidity pattern of respiratory diseases among age groups at each location. Males in humid forest and derived savanna reported respectively about 56.7% and 59.0% of the specific respiratory diseases. Out of all the respiratory diseases considered, bronchial asthma, lobar pneumonia, sinusitis and tonsillitis are statistically significant with weather variables in humid forest (Ile-Ife) while bronchial asthma, bronchopneumonia, cardiac asthma and lobar pneumonia are statistically significant with maximum air temperature (p<0.05) in derived savanna (Ilorin). Further analysis showed that maximum air temperature accounted for 46.6% (r= 0.68) and 43.3%(r=0.66) of bronchial asthma (p<0.05) at humid forest and derived savanna, respectively. Similarly, air temperatureexplained39.1%, 39.8% and 43.8% of bronchopneumonia, cardiac asthma and lobar pneumonia occurrence in derived savanna respectively. Relative humidity accounted for 36.3% of tonsillitis morbidity and in combination with wind speed, explained 82.1% of lobar pneumonia in humid forest. Maximum temperature and wind speed accounted for 69.3% of the occurrence of sinusitis at humid forest. The study advocates the importance of inclusion of thermal environment into monitoring and surveillance of respiratory diseases transmission.