Public Transport : A major risk factor in transmission of viral infections

Have you recently traveled by buses or trains? Public transport users stand a high risk of acquiring respiratory infections. Take necessary precautions and stay alert!

In recent years the world has witnessed the onset of many pandemics including Swine flu (H1N1 Influenza), Bird Flu et al. Use of protection masks, hand sanitizers and the likes has been prevalent ever since. It is a general belief that any infection spreads faster in a public places. This may be attributed to the increased chances of closer proximity with infected people in public places, specifically while using public transport. However, the relation between the use of public transport and the risk transmission of respiratory infections in such places is of prime importance during epidemics and pandemics.

A case-control study was carried out during the influenza season in the year 2008-2009 to investigate the association between bus or tram use and the spread of respiratory infections. The study included a survey consisting of case-specific questions. Sections of the survey were aimed to identify the use of public transport viz., buses, trains or trams within the five day period before onset of the flu symptoms. This five day period represents the maximum accepted incubation period for any respiratory infection. Other sections dealt with the period of up to five days after symptom onset, to identify instances of using public transport and the transmission of flu since this involved potentially exposing the infection to others.

The key finding of the study indicated that occasional habitual use of public transport poses higher risk of transmission of respiratory infections. Infrequent public transport users stand as much as six times higher risk of getting an acute respiratory infection as compared to the regular users. Use of public transport within five days of symptom onset was found to be associated with a six-fold increased risk of respiratory infection. The risk appeared to alter with the degree of habitual bus and tram use. This trend was however, not statistically significant.Nevertheless, the trend can be attributed to some credibility in the sense that there is greater likelihood of developing protective antibodies to the viruses causing common respiratory infections if a person is exposed such an environment on a regular basis.

In the interest of public health care various strategies are employed during pandemics including issuance of warnings to the public to employ every possible preventive measure, free distribution of medication and other medical facilities, and in some cases even closure of the public transportation systems to prevent any further damage to the public health. The findings of the study also emphasize on the need to maintain good hygiene both by infected and non-infected people specifically when using public transport like buses or trains. People who are infected need to take extra care and preventive measures to avoid spreading of the virus. During a severe pandemic, it is always in highest public health interest to avoid the use of any public transport as far as possible.


Is public transport a risk factor for acute respiratory infection? A Study by oy Troko, Puja Myles, Jack Gibson, Ahmed Hashim, Joanne Enstone, Susan Kingdon,Chris Packham, Shahid Amin, Andrew Hayward and Jonathan Nguyen-Van-Tam
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Author: Ann M
Editor: Dr.Bimal Rajalingam
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Disclaimer: This article is written by a non-medical professional.