Emergencies preparedness, response

Plague in Madagascar

What is the situation of plague in Madagascar?

CORRIGENDUM 19 February 2015

* This sentence was updated from: From August 2014 to end-December 2014, 13 cases were detected there.

** This sentence was added to provide additional clarification.

11 February 2015 -- WHO and Madagascar’s Ministry of Health have completed a second investigation of the plague situation in that country. The investigation was further supported by experts from the Plague Central Laboratory at the country’s Institut Pasteur.

The outbreak, which began in September 2014 and peaked from November through end-December, has slowed for the time being. However, the plague season on the island continues until April. Health officials are keeping a close watch over the situation, especially after the disruption caused in mid-January by heavy rains and flooding from Tropical Storm Chedza.

Plague has a well-documented high epidemic potential, especially in its pneumonic form, which can spread directly from one person to another via coughing. Evidence that the disease has gained a foothold in slum areas of Antananarivo, the capital city, reinforces the need for heightened vigilance. On November 2014, 2 cases (1 probable, 1 confirmed) were detected there.* No human case has since been reported in the capital.**

Altogether and since September 2014, 263 cases, including 71 deaths, have been reported to date, representing a case fatality rate of 27%. The district of Amparafavarola in the central highlands has been the most heavily affected area, where cases of pneumonic plague continued to be reported during the first week of January.

Treatment with common antibiotics such as tetracyclines, gentamycin or streptomycin are efficient on human plague but their efficacy depends on early detection. When this is the case, case fatality can be reduced from 60% to less than 15% for bubonic plague. This is especially important for the pneumonic form, which is highly contagious, can kill in less than 24 hours, and is invariably fatal in the absence of treatment.

A robust and sensitive diagnostic test, developed at the country’s Institut Pasteur and subsequently introduced elsewhere in Africa and in South America with WHO support, produces reliable results in 15 minutes, greatly facilitating containment efforts. However, control of plague outbreaks in Madagascar has been complicated by development of resistance to deltamethrin – the first-line insecticide – in the fleas that transmit the disease from rats to humans.

Plague is endemic on the island, where outbreaks have resurfaced nearly every year since 1980. Over the past 3 years, the annual number of cases has steadily increased, making Madagascar the country most severely affected by plague worldwide.

On 4 February 2015, the African Development Bank announced a grant of US$ 1 million to support the containment of plague and other epidemic-prone diseases in Madagascar. The grant, which will be managed by WHO in collaboration with the Ministry of Health, is being used to upgrade isolation and laboratory facilities and to purchase antibiotics, insecticides, diagnostic kits, and equipment, including personal protective equipment for front-line responders.

Worldwide, the distribution of plague is geographically localized to areas where conditions of landscape and weather favour a high concentration of rodents and fleas. WHO has identified natural plague foci in around 20 countries in Africa, America, and Asia. Weak health systems and low standards of environmental hygiene are risk factors for outbreaks of human plague.

WHO recommendations

WHO does not recommend any travel or trade restriction based on the current information available.**

For more information please contact:

Fadéla Chaib
WHO Department of Communications
Mobile: +41 79 475 5556
Telephone: +41 22 791 3228
Email: chaibf@who.int