of commuting by public transit.

Two years ago, after TriMet made drastic cuts to its bus-cleaning operation, The Oregonian commissioned a team of Portland State University microbiologists to test seats, hand straps and rails on various vehicles. The scientists found oxacillin-resistant staphylococcus aureus among the 120 bacteria colonies found on trains and buses. Commonly known as MRSA, the bug is notorious for rejecting antibiotics, eating flesh and causing pneumonia.

Whooping cough, on the other hand, is a bacterial infection that can spread through the air via microscopic droplets when people cough. People with whooping cough have coughing or sneezing spells in which they can’t catch their breath between coughs, causing them to make "whoop" sound as they attempt to catch their breath.

In the 1970s, health authorities believed they had allbut vanquished the sickness, but cases have popped up increasingly in recent years.

Nationally, 48,277 cases of whooping cough were reported in 2012, which is the highest number reported in the U.S. since 1955.

Experts blame the spike on fewer parents vaccinating their children as well as a switch from "whole cell" pertussis vaccine to a more purified "acellular" mix, which wear off in children by about the age 10 and requires a booster shot.

"People need to remember to get that booster," said Susan Wickstrom, a spokeswoman for the Oregon Health Authority's public health division.

In 2012, Oregon had more than 900 whooping cough cases, the most since the 1950s, Wickstrom said. In the past decade, four infants have died from Pertussis in Oregon. "It affects babies the worst," she said.

But