MANILA — Overcrowding is “a major source of infection”, an expert from the University of the Philippines said Wednesday, after regulators eased physical distancing rules meant to stop the spread of the novel coronavirus in the mass transport system.

The transportation department on Monday lowered the distancing requirement to 0.75 meter from 1 meter to accommodate more passengers in public vehicles. The government plans to further ease the threshold to 0.5 meter on Sept. 28, and then down to 0.3 meter by Oct. 12.

While passengers are still required to wear anti-virus masks and face shields, this is not a 100-percent guarantee that those who have COVID-19 will not expel respiratory droplets that spread the disease, said Dr. Guido David of the interdisciplinary research team UP OCTA.

If distancing requirements are further reduced to 0.3 meters, or about the length of a ruler, a bus for instance could have as many as 100 passengers. A lone passenger with COVID-19 can infect up to 35 percent of the people in the same vehicle, David said, citing studies.

“Overcrowding is one of the major sources of infection. Proven na ‘yan (that has been proven),” he told ABS-CBN’s TeleRadyo.

“Pag isang ruler na lang, ang magiging problem natin iyon sinasabi nating overcrowding, iyon ang talagang high risk of transmission. Kunyari nasa isang bus… kung 1 ruler na lang, puwede nang punuan. Parang iyong dati na tambakan na ang mga tao, kahit nakatayo na, mayroong tao na nasa bungad,” he added.

(If the required distance will only be about a ruler’s length, we will have a problem with overcrowding, which will bring a high risk of transmission. If for example, we are in a bus, it can be packed. It will be like before where people are jammed together, some are standing, and some are even at the doors already.)

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The World Health Organization urges the public to keep a distance of 1 meter from others to dodge the virus. When someone coughs, sneezes, or speaks they spray small droplets from their nose or mouth which may contain the virus, the WHO said.

David said he had yet to read research recommending less than 1 meter of physical distancing.

Inconsistent distancing rules in mass transport and other public areas may spawn confusion. It will also be harder to estimate a distance of 0.75 meter compared to 1 meter, which is about an arm’s length, he said.

Instead of easing distancing requirements, the government should provide more modes of transport, suggested David.

Transportation Secretary Arthur Tugade said Tuesday his agency ran a simulation at the Philippine National Railways before lowering distancing requirements.

The move is "not a product of a knee-jerk reaction, but also a product of research and a product of simulation," he told lawmakers.

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