What is the plague that has hit China and why there is alarm in that country

Two people in Beijing were diagnosed with the pneumonic plague Tuesday, which is known to be the most deadly version of the disease.

Two people in China have been infected with pneumonic plague, the most contagious form of the disease (representational image)

New Delhi: Two people in Beijing were diagnosed with the pneumonic plague Tuesday. The pneumonic plague infects the lungs and though lesser known than the bubonic plague, is more deadly, as it can be transmitted between humans. 

According to Chinese officials, the two infected people came from Inner Mongolia and travelled to Beijing seeking treatment. Public health officials are now working to ensure that the disease does not spread. 

The news, however, has caused alarm among Chinese citizens with someone taking to the popular social media site, Weibo, to put pressure on the government to release information on how the two travelled to Beijing, particularly if they used public transport.

The World Health Organisation (WHO) has confirmed that Chinese authorities have notified it about the cases of plague. 

What is the plague?

The plague is a disease caused by the bacteria Yersinia pestis, which is found in animals, particularly rodents. It can be transmitted to humans through infected animals and fleas.

In the Middle Ages (5th-15th century), plague was also known as the ‘Black Death’ as it was responsible for the deaths of millions of people in Europe. 

There are three types of plague: bubonic plague, pneumonic plague and septicemic plague. 

Bubonic plague: This infects a person’s lymphatic system (which is a part of their immune system), causing inflammation in the lymph nodes. If left untreated, the bubonic plague can also convert into either pneumonic of septicemic plague. Its symptoms include fever, chills, weakness and headaches. 

Pneumonic plague: According to WHO, pneumonic plague is the ‘most virulent form of plague’ and can be  fatal within 24 to 72 hours. It occurs when the bacteria infects the lungs. It is the only type of plague that can be transmitted from human to human. Symptoms are chest pain, fever and cough. It is highly contagious and transmissible merely by coughing. 

Septicemic plague: This is when the bacteria enters the bloodstream and multiplies there. If left untreated, pneumonic and bubonic plague can lead to septicemic plague. A person infected by septicemic plague may also notice their skin turning black.

How to treat and control plague 

 Though reported cases are rare, there have been plague outbreaks as recently as 2014 in China, 2015 in the US and 2017 in Madagascar, where there were 2,417 reported cases and a death toll of 209.

The plague is a life-threatening disease but if caught early, can be treated with antibiotics. However, without prompt treatment, the disease can lead to serious illnesses and even death. At times, antibiotics alone are not enough — additionally intravenous fluids and extra oxygen are required to treat a person. 

Since it is highly contagious, those who are infected with pneumonic plague are kept in isolation. And people in close contact with the person infected are given a dose of antibiotics as a preventive measure. 

 Other preventive measures to curb a plague outbreak are to keep the rodent population in control with pest control measures, ensuring that surrounding areas are clear of stacks of wood that rodents feed on among others. 

Plague vaccines are being developed but it is highly unlikely that they will be available in the near future.