November 03, 2017

Many media outlets are sensationalizing the current plague outbreak in Madagascar and its risk of spreading to neighboring countries. People typically associate plague with the Black Death that killed an estimated 50 million people in Europe during the 14th century. However, plague can now be treated with conventional antibiotics when detected in time and is easily prevented by practicing basic health and insect bite precautions, or taking post-exposure antibiotics. While you should be aware of the current plague outbreak in Madagascar, you should not panic. In fact, the World Health Organization (WHO) currently recommends against any restrictions on trade and travel to Madagascar and the US CDC has only issued a travel health notice encouraging travelers to practice enhanced health precautions - predominantly avoidance of flea bites and diligence in personal health precautions, in the case of plague.  

What is the Current Plague Situation in Madagascar? 

According to the most recent situation report from the WHO, dated Oct. 31, plague activity in Madagascar is decreasing following the implementation of coordinated and strategic approaches to prevent, detect, and control disease activity. As of Oct. 30, health officials have identified approximately 1,800 plague cases, including 127 related deaths, since the start of the outbreak in August. Disease activity has occurred in multiple regions, though the majority of cases have occurred in Analamanga Region. 

Districts Affected by Plague Activity in Madagascar, Aug. 1-Oct. 30, 2017

Why is the Plague Outbreak in Madagascar a Concern?

It is important to understand that there are multiple types of plague and their names are based on where the bacteria accumulates in the body. The two main types are bubonic plague and pneumonic plague. Bubonic plague is the most common form of plague and occurs when the bacteria accumulates in a person's lymph nodes; this form is caused by the bite of infected fleas and is not easily transmitted person to person. Bubonic plague can progress to pneumonic plague if the bacteria spreads through the bloodstream and accumulates in the lungs. Pneumonic plague can transmit directly from person to person through cough droplets containing plague bacteria. While any form of plague can be fatal if left untreated, pneumonic plague is generally more serious than bubonic plague. The current outbreak in Madagascar is of concern because it is predominately being caused by pneumonic plague and is affecting large urban areas, which increases the risk of transmission.  

What is the Risk of Plague Spreading from Madagascar to Other Countries?  

First and foremost, it is important to note that plague has not spread to any additional countries. According to the WHO, the risk of international spread is moderate because the occurrence of travel to neighboring countries and territories is frequent; however, only a limited number of cases have been reported in travelers. The WHO has identified the following countries and territories as priority areas for plague preparedness and readiness due to their trade and travel links to Madagascar: Comoros, Ethiopia, Kenya, Mauritius, Mozambique, La Réunion (France), Seychelles, South Africa, and Tanzania. These regions have implemented measures in coordination and collaboration with international health organizations to mitigate risk associated with the importation of pneumonic plague cases and possible spread. These measures include increasing public awareness and disease surveillance, conducting contingency planning, and prepositioning equipment needed to identify and manage potential cases. Even if a few cases were imported from Madagascar to surrounding countries, they would likely be quickly identified and isolated. 

When Will the Current Plague Outbreak in Madagascar End? 

While is it is impossible to predict exactly when the current outbreak will end, it is highly likely that pneumonic plague activity will continue to decline in the coming weeks if ongoing public health operations are sustained. However, do not be surprised if officials report additional outbreaks in the near future; plague is endemic to Madagascar and the season typically occurs between September and April. Madagascar typically reports 200 to 700 plague cases per year. While outbreaks of pneumonic plague are rare in the country, outbreaks of bubonic plague regularly occur, as fleas that transmit the plague bacteria have become highly resistant to insecticides. 

What Precautions Can I Take to Protect Myself?

All forms of plague cause nondescript symptoms, such as fever, chills, and extreme weakness. If left untreated, any form of plague can be fatal. Fortunately, several common antibiotics can provide effective treatment and may also be used as prophylaxis against plague.  

Individuals who develop symptoms of plague should seek immediate medical attention. Individuals should avoid visibly ill people and emphasize basic health precautions, especially frequent hand washing with soap and water, or an alcohol-based hand sanitizer if soap and water are unavailable. Travelers to Madagascar should also avoid crowded areas; avoid exposure to fleas, wild rodents, and stray animals; and take precautions to avoid flea bites when outdoors by using an insect repellent that repels fleas and wearing long-sleeved shirts and pants when weather permits.