Health officials in Africa are investigating two separate outbreaks of unknown illness, a small one in Niger that has killed nearly a third of patients and a larger one in Tanzania in which no deaths have been reported so far, the World Health Organization (WHO) African regional office said today.
Deadly outbreak in Niger
In Niger, the outbreak as of the middle of October had sickened 23 patients in two villages in Tera District, located in the country's Tillaberi Region. The area is located in far southwestern Niger, not far from the Burkina Faso and Mali borders. Seven deaths have been reported, according to the WHO report.
Symptoms included fever, dysphagia, nosebleeds, vomiting, neck pain, submandibular lymphadenopathy, and ulceronecrotic tonsil lesions. However, none of the patients had a pseudomembrane at the back of the throat, which is a hallmark feature of diphtheria. Also, nosebleed, which occurred in five patients, isn't a common diphtheria symptom.
Throat swabs from five patients were negative for diphtheria, and blood tests from two patients were negative for mononucleosis. These tests were done at the Centre for Medical and Health Research (CERMES), a Pasteur Institute lab that operates under Niger's public health ministry.
Given the unusual symptoms, negative lab tests for diphtheria, and high case-fatality rate, further investigations are needed to determine the outbreak's scope, source, and risk of further spread, the WHO said. The office said the WHO is assisting Niger's health ministry investigators and has deployed an epidemiologist to provide technical support in coordinating the work.
Almost 800 cases in Tanzania
Meanwhile, Tanzania's health ministry is investigating an unknown disease in Kasulu district, located in the northwestern part of the country not far from the Burundi border. Since late August, 794 illnesses have been reported, none of them fatal, according to a separate WHO outbreak report.
The main symptoms are fever, headache, vomiting, and abdominal pain, but tests for dengue fever conducted on some of the patients were negative. The WHO said more tests are under way to determine the cause of the outbreak and that health officials are weighing several possibilities, including dengue fever, yellow fever, and hepatitis A or E.
In response to the outbreak, health officials have intensified health education about environmental hygiene and sanitation and have strengthened surveillance and lab analysis of samples, according to the report.
Sharon Sanders, editor-in-chief of the infectious disease message board FluTrackers, told CIDRAP News that the group's volunteers follow developments in the two countries, but added that Africa is a challenging area to monitor, because the news coming out of the region is sparse. She said malaria and cholera seem to be chronic in the area over the past months, and health officials in Niger recently detected the country's first diphtheria cases in 7 years.
She said it's not unusual to see news stories about "unknown" diseases appear in the African media, which are usually resolved in a few weeks after global health groups arrive to assist with testing. However, Sanders said it is unusual for a WHO division to report an unknown disease outbreak.
"We are going to carefully watch this," Sanders said, adding that reports of nasal bleeding in the Niger outbreak patients are worrying and that she would like to know if bleeding is a feature in any of the Tanzanian cases.
Nov 20 WHO Africa regional office Niger outbreak notice
Nov 20 WHO Africa regional office Tanzania outbreak notice