Why haven't we heard of this?

Because effective medical treatment exists and is available, and because there is little threat of international spread.

Madagascar plague outbreak has killed 133, may be slowing down

Plague is caused by infection with the bacterium Yersinia pestis and is typically spread through the bite of infected fleas, frequently carried by rats, causing bubonic plague.

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Pneumonic plague is more virulent or damaging and is an advanced form characterized by a severe lung infection. 

The infection can be transmitted from person to person via airborne droplets -- coughing or sneezing. 

The incubation period is short, and an infected person may die within 12 to 24 hours.

Symptoms of the plague include fever, chills, painful and inflamed lymph nodes, or shortness of breath with coughing and/or blood-tainted sputum arise. 

It is important to seek medical attention immediately if any of these arise, Jasarevic said.

Both forms of the plague can be treated with antibiotics, making early detection a priority.

. . . .

Extensive screening measures, informed travelers, short incubation periods of pneumonic plague, and increasing operational readiness of surrounding countries and islands has kept the risk of international spread low, said the WHO.

"The risk of international spread is low, because generally, people with plague are too sick to travel," said Dr. Charlotte Ndiaye, a WHO representative in Madagascar.

Her organization is working closely with airport authorities to ensure that sanitary measures such as temperature checks and medical teams are in place at airports and ports to prevent the spread of infection outside the country. 

The group is also working closely with neighboring countries.