Hommam Al Nassim 
An illness of unknown causes has emerged in Nigeria, killing four people and infecting dozens in the northwest of the country.
Medical teams headed towards the city of Sokoto, near the border with Niger, to investigate the causes of this mysterious disease, the first cases of which were recorded on March 21st.
Reports from the local press showed that symptoms of the disease include fever, vomiting, sudden weight loss, and swelling of the abdomen.
Dr Jaid Idris, director general of the Nigerian Centre for Disease Control and Prevention, said these cases are not the first of their kind, as similar cases were documented last year without an accurate diagnosis.
Idris said evidence suggests high levels of lead and chromium in the blood samples of those infected, raising concerns about local activities such as mining and agriculture that use chemicals that could cause pollution.
Dr. Idris urged affected communities to be vigilant and immediately report any symptoms to local health centers.
Nigeria recently suffered from an outbreak of Lassa fever, which was transmitted by rodents and has led to more than 150 deaths since January, as well as an outbreak of diphtheria last year, which killed more than 600 people, most of them children.
18 people died in a series of bombings that rocked northeastern Nigeria