Malawi Public Health Institute and One Health partners prevent human transfer in anthrax outbreak

 

In late 2018 and early 2019, the Public Health Institute of Malawi successfully responded and contained an anthrax outbreak among the local hippopotamus population, in collaboration with One Health partners.

 hippo

The outbreak began in October 2018 when local public health authorities started noticing an increasing number of dead hippopotami floating on the Shire River, which runs alongside Liwonde National Park in Southern Malawi. The Shire is the country’s largest river and Lake Malawi’s only outlet.

The Public Health Institute of Malawi (PHIM), along with the Department of Wildlife and the Ministry of Agriculture, Irrigation and Water Development, opened a joint investigation to investigate the cause of these deaths. Two PHIM officers were sent to secure specimens from the hippopotami and restrict access to the zone, preventing any bioterrorism-related risk.

Samples, such as animal carcasses and water, were tested in two national laboratory facilities: the Central Veterinary Laboratory and the PHIM laboratory. They quickly revealed that the hippopotami were dying from anthrax, a serious bacterial disease caused by Bacillus anthracis. 

Anthrax is known to kill wild and domestic animals, and sometimes humans, typically infecting the skin, gastrointestinal track, and lungs. One of the biggest risks was direct transmission. Although anthrax does not spread easily, the spores can survive in the soil for years before it infects an animal or human. Infection occurs when animals or humans breathe in the spores, ingest the spores from contaminated food or water, or the spores enter through a cut or scrape in the skin.

Once the anthrax was confirmed in hippopotami, PHIM coordinated a multi-agency response based on the principles of One Health. One Health is the concept that recognizes that human, animal and environmental healths are deeply connected. At PHIM’s weekly One Health meetings, multi-disciplinary groups from different ministers shared updates on the outbreak, and mobilized resources and relevant partners. The strengths and weaknesses of the response activities were assessed, and participants prepared reports that were sent out to other Malawian government agencies and to the World Organization for Animal Health (OIE), an intergovernmental organization coordinating, supporting and promoting animal disease control. For real-time information sharing, the teams responding to the outbreak created a dedicated WhatsApp forum on anthrax.

At the district level, public health emergency committees met weekly in the affected districts of Balaka and Machinga. Both districts were given extra antibiotics and supplies in case the outbreak was to transfer to people. PHIM staff, local farmers and wildlife personnel were kept informed about the outbreak and response. Public service announcements were made to school children, at village meetings and through public address systems such as town criers sharing information about how to protect themselves from contracting anthrax.

Health officials conducted aerial surveillance to locate animal carcasses in and adjacent to the containment zone. Local police assisted with the response by intervening to stop people in local communities from using dead animals for food; this action helped prevent human infection. 

“The health of the wildlife is directly linked to the health of the people”, explained PHIM Director Dr. Matthew Kagoli. He pointed out that wildlife grazes in the same environment as domestic animals, and, when this environment is contaminated, domestic animals can in turn contaminate the communities. Those animals were also closely monitored.

The comprehensive response was a success. Between October and early December 2018, 39 hippopotami were found to have died of anthrax. In December, the death rate stabilized and then began to drop. The last reported hippopotamus death was January 3, 2019. The outbreak was contained to 48 hippo deaths, with no transmission to humans or domestic animals.

According to Dr. Kagoli, the outbreak allowed the country’s health leaders and PHIM, a NPHI with only a few years of existence, to demonstrate effective and efficient response capabilities. The PHIM was able to bring everyone to the table and coordinate with ministries and partners in a way that would not have been possible in the past. Dr. Kagoli added that community engagement was key to this success.

 

This article was first published in IANPHI Insider #5 (February 2020).