Comparative Assessment of Indoor Air of a Tertiary Hospital and a Public Secondary School in Ilorin, Kwara State, Nigeria

Air bone transmission is one of the routes of spreading diseases responsible for a number of nosocomial infections [1]. Airborne microbial particles have negative effects especially on the health of immunocompromised people [2]. The infections are caused by aerosols which are small, viable and may remain suspend in the air stream over long period of time. This study was aimed at investigating and comparing the quality of indoor air of a tertiary hospital and a secondary school in Ilorin, Kwara state, Nigeria. Air samples were collected in the hospital and school using settle plate techniques. Bacteria isolated from different wards in the hospital were Staphylococcus aureus, Coagulase negative Staphylococcus, Bacillus spp., Klebsiella spp., Micrococcus spp., Escherichia coli, Pseudomonas spp., Acinebacter spp. The female surgical ward (FSW) had the highest degree of contamination of bacterial and fungal air borne while the bacterial isolates gotten from the school were heavy growth of Coagulase negative Staphylococcus and Bacillus spp., and few growths of Klebsiella spp. and Acinebacter spp. with highest bacterial count in J.S.S.2B class. For fungal growth Aspergillus spp. and Mucor spp. produced numerous growths in all the classes and in the hospital while Penicillium spp. gave scanty growth. The lowest bacterial count observed both in school and in hospital was still high when compared with British bacteriological standard.


Introduction
Indoor air quality refers to the air within and around buildings and structures. It Advances in Microbiology can be made unsafe for human use by some compounds, such as carbon monoxide, volatile organic compounds, particulate matter and microbial contaminants, such as moulds, bacteria and viruses [3]. Dust is a good vehicle of air borne contamination and emanates from human activities, such as sweeping, movement, waving of handkerchief and bed making [4].
Patients with community acquired infection are frequently admitted to the hospital and the diseases may spread nosocomially by either direct contact, contact with contaminated food, water, medication or medical devices (fomities) or by air borne transmission [5]. Many bacteria are spread through air which includes Mycobacterium tuberculosis, Bacillus anthracis, Bordetella pertusis which cause pulmonary tuberculosis, pulmonary anthracis and whooping cough respectively [6]. These diseases may be fatal if not treated early. Fungi, such as Apergillus niger, Candida albican and Penicillium are capable of causing hospital acquired infections.
There is a need to assess indoor air quality especially in institutions, such as hospital settings, nursing homes, prisons, schools, dispensaries and banks which are characterized by influx of people, because it has been reported that contaminated air can cause both mild and severely irritating health conditions [7].
It has been reported that air borne bacteria in the hospital environment have been a major source of post operative infection and serious problem in the intensive care unit [8].
This study was aimed at investigating the quality of indoor air of a tertiary hospital and a secondary school in Ilorin, Kwara State, Nigeria.

Materials and Methods
This work was carried out at University of Ilorin teaching hospital and Ilorin

Results
The highest number of bacteria was observed in female surgical ward and the lowest in the operation theatre as shown in Table 1 Table 2. Also, female surgical ward had highest number of fungi and lowest number of fungi recorded was in the operation theatre in   Bacillus spp., and few growths of Klebsiella spp. and Acinebacter spp. as shown in Table 5. Table 6 shows that the fungi namely Aspergillus spp. and Mucor spp. produced numerous growths in all the classes while Penicillium spp. gave scanty growth.

Discussion
Build up of infection aerosols exacerbates with care challenges and developing country as the role of airborne microorganisms in hospital acquired infections (HAIS) has been recognized [2]. Airborne microorganisms contaminated are usually introduced into the air through production of aerosol droplets by human via coughing, sneezing and talking.
In door environments, the main source from microbes is usually the outdoor air [9].
The results showed that the female surgical ward (FSW) had the highest degree of contamination of bacterial and fungal air borne followed by male surgical wards. This was also observed by Awosika et al. [4]. This high viable count in these wards might be associated with improper ventilation, high movement of individuals and poor level of awareness among the staff and routines wound dressing which might result in shedding of bacteria, especially when those patients have surgical site infections. The total viable microbial count in female surgical ward and male surgical ward showed high contamination level and exceeded available local guideline according to Ekhaise et al. [10] [11] [12].   [13].