The trials for automatic sliding doors on local trains may have begun, but city doctors fear this could lead to a spread of communicable diseases such as influenza and tuberculosis (TB). The reason: “Poor ventilation and overcrowding”.
Experts said overcrowded compartments in regular local trains posed a risk of the spread of airborne diseases, but now with closed doors, the risk of contracting contagious infections will increase.
City doctors have called for a health impact assessment. “Overcrowding is the most common factor leading to the spread of any infection in the community. With open doors, there was enough ventilation, but now we fear a faster transmission of infections, especially TB,” said Dr Yatin Dholakia, secretary, Maharashtra state anti-TB association.
An untreated TB patient can infect about 10-15 people in a year. A person infected with an airborne infection can spread it to others by releasing the germs or microbes while sneezing and coughing.
According to the Mumbai Railway Vikas Corporation (MRVC), there are around 14 to 16 passengers per square metre of floor space during peak hours. And in a nine-car rake, which has a capacity of 1,726 passengers, there are as many as 4,500 people travelling during peak hours.
Public health experts said in the absence of proper ventilation, there could be an “epidemic” like situation.
“We don’t have any reference because the public transport in Mumbai is unique in terms of the number of passengers and climatic conditions,” said Dr Om Shrivastav, director, infectious disease department, Jaslok Hospital, Peddar Road. “Even if we have the best available ventilation system, the closed–door trains should not be replicated until we study the risk of contracting the illness.”
Experts said a majority of suburban railway networks function with air conditioned rakes that had closed doors, ensuring better ventilation.
Sharat Chandrayan, CPRO, Western Railway, said, “We have adopted a forced ventilation mechanism, which is superior to the Metro rail because it does not circulate the same air. It keeps the air quality better and the carbon dioxide levels at half the permissible limits. Slits in the doors provide better ventilation.”
The rationale behind closed-door trains was to avoid deaths because of overcrowded trains. Last year, nine people died every day in railway accidents across the city’s rail network.
According to Dr Rohini Chowghule of Indian Institute of Environmental Medicine, the chance of contracting an infection also depends on the period of exposure to the infected person. “If the railways have maintained basic ventilation and people keep their immunity up, the risk of contracting infections will not change. Closed doors will save many lives, but ventilation should not be compromised,” said Dr Chowghule.