Anthrax is a disease that occurs regularly in Zambia and is considered endemic. It is mostly seen between May and January, and usually peaks between October and November at the end of the dry season. The International Health Regulations National Focal Point of Zambia notified the World Health Organization of an anthrax outbreak on November 1, 2023. Even though cases are seen every year, WHO labeled it a large-scale outbreak and stated that an anthrax outbreak like this one has not been seen in Zambia since 2011 when there were 511 suspected human cases. They also mentioned that the illness was spreading throughout the Luangwa, Kafue, and Zambezi river basins.
Before getting into more detail about the situation, we should first understand what kind of disease anthrax is. Anthrax is the result of gram-positive, rod-shaped bacteria, also known as, Bacillus Anthracis. It forms naturally in the soil and usually impacts domestic and wild animals worldwide. It can also affect humans if they get in touch with infected animals or contaminated animal products. It is considered a severe infectious disease since it can cause serious illness both in animals and humans. Domestic and wild animals, which can include deer, antelope, goats, sheep, or cattle, become infected with the disease when they ingest or breathe in spores from contaminated plants, soil, or water. So, it has quite a lot of opportunities to spread. Therefore, it is advised to routinely vaccinate areas with anthrax histories to prevent outbreaks. People get infected the same way as animals, which is basically when spores get into their bodies through eating, drinking, breathing, or cuts in the skin. When spores are inside the body, they can be “activated” and become anthrax bacteria which can result in them spreading uncontrollably, producing toxins and causing serious illness. Anthrax doesn’t usually spread from person to person, but only from animals to humans. The two main activities that can increase the risk of contracting anthrax in humans are handling contaminated animals or animal products and consuming raw or undercooked meat from contaminated animals. Anthrax treatment mainly includes a 60-day treatment with antibiotics or a three-dose series of anthrax vaccines, but these vaccines are not always available to the general public. Anthrax is most common in central and south America, sub-Saharan Africa, central and southwestern Asia, southern and eastern Europe, and the Caribbean.
There are many types of anthrax, and their symptoms vary. Skin-related (cutaneous) anthrax infections are the most common but also the mildest types of infections, and their symptoms usually include swelling in the sore and nearby lymph glands, flu-like symptoms, and an itchy bump that is like an insect bite that quickly develops into a painless sore with a black center. Gastrointestinal anthrax, which is caused by eating undercooked meat from an infected animal, usually shows symptoms such as nausea, vomiting, abdominal pain, headaches, loss of appetite, fever, a swollen neck, and a sore throat. Injection anthrax, which, for now, has only been seen in Europe and is caused by illegal drug injections, has symptoms like redness at the area of injection without the area turning black as it does in cutaneous anthrax, significant swelling, shock, multiple organ failure, and meningitis, which is the swelling of the protective membranes covering the brain. The last and most deadly type of anthrax is inhalation anthrax, which can be fatal even when treated. Its symptoms include flu-like symptoms, mild chest discomfort, shortness of breath, nausea, coughing up blood, high fever, painful swallowing, trouble breathing, shock, and meningitis. The two complications that lead anthrax to be fatal are the body not being able to respond to infection normally which leads to damage to multiple organ systems, and inflammation of the membranes and fluid covering the brain and spinal cord which leads to massive bleeding (hemorrhagic meningitis) and death.
The first human cases of anthrax this year in Zambia were reported on May 5 at Dengeza Health Post in the Sinazongwe District of the Southern Province. At about the same time, there were reports of animals in the surrounding areas dying from unidentified causes. Animal and human cases were reported in the Kanchindu and Siameja veterinary camps of Sinazongwe District in June 2023, with 26 humans contracting gastrointestinal anthrax after consuming meat from three wild hippopotamus carcasses. The Lusaka Central Veterinary Research Institute (CVRI) confirmed the first human case through laboratory culture on June 16, 2023. On July 17, 2023, cattle and goat specimens were tested for anthrax using culture at the Lusaka CVRI and the results came back positive. 684 suspected human cases were reported from 44 out of 116 districts in nine of Zambia’s ten provinces as of November 2023, with 4 total deaths. The most affected provinces are the Southern with 54%, Western with 13%, Lusaka with 12%, Eastern with 10%, and Muchinga with 7%. Shinazongwe district is considered the center of the epidemic, with 42% of total cases and 50% of total deaths. In the case of animals, across 11 districts, 568 domestic and wild animal cases were reported as of November 21.
There has been a noticeable increase in cases since September which is indicative of the unrestricted animal movement between provinces contributing to the increased risk of the disease spreading. In addition to that, limited awareness about anthrax, sociocultural norms, and poverty significantly contribute to the spread of the disease since most people are concerned about their livelihood rather than the risk of contracting anthrax. As previously mentioned, the epidemic is extending along the Zambezi, Kafue, and Luangwa river basins. Since these rivers also flow into Lake Kariba in Zimbabwe, Kahora Bassa in Mozambique, and Lake Malawi, there is a higher chance that anthrax will spread to neighboring countries. Given this information, it makes sense that the epidemic is being classified as a large-scale outbreak.
Actions to stop the spread of anthrax have been taken for both animals and humans. Livestock are being vaccinated with the help of the Food and Agriculture Organization of the UN, and vaccination campaigns have been started. Meat inspections are being done in butcher shops and abbatoirs. The supply of necessary medical equipment has been prioritized. Moreover, the Department of Wildlife and Parks has been conducting patrols to stop illegal animal movements and make sure animal carcasses are being disposed of correctly. If actions like these keep being taken and the government focuses on further educating its citizens on the subject, it wouldn’t be a surprise for the outbreak to be taken under control shortly.
CDC. “Basic Information | Anthrax | CDC.” Cdc.gov, 28 Jan. 2019.
Mayo Clinic. “Anthrax - Symptoms and Causes.” Mayo Clinic, 2017.
WHO. “Anthrax - Zambia.” Www.who.int, 8 Dec. 2023.