Four people have been killed and dozens sickened by a 'strange' illness in Nigeria.

All of the cases have occurred in Sokoto, in the north-west of the country, close to the border of Niger. 

Concerned health chiefs have now been dispatched to the area to investigate the nature of the illness. 

Details on what the actual disease is are scarce. 

Local media reported people have been struck down with symptoms such as fever, vomiting, sudden weight loss and abdominal swelling. 

The deaths have all been recorded from March 21. 

In total, 164 cases — mainly involving children aged between four and 13 — across the area have been logged. 

Of these, four patients were hospitalised.

Another 130 have received treatment either at home or in local primary care centres. 

At a press briefing in the country's capital Abuja on Tuesday, director general of the Nigeria Centre for Disease Control and Prevention (NCDC) Dr Jide Idris, said 'notably this is not the first occurrence', according to the Nigerian Observer. 

He added: 'A similar incident was documented in 2023. That one went without a conclusive diagnosis.

Cases have all been logged in the city of Sokoto (pictured), in the north-west of the country, close to the border of Niger. Concerned health chiefs have now been dispatched to the area to investigate the nature of the illness

'Results indicate varying levels of lead and chromium in blood samples, prompting scrutiny of local activities such as mining and agricultural practices involving chemical usage.'

However, he noted: 'The collaborative efforts extend beyond health institutions, encompassing government agencies, research bodies, and community stakeholders.

'At the moment, security challenges hamper access to affected areas, complicating response efforts.' 

Communities affected by the outbreak should be vigilant, he urged, and report any potential symptoms immediately to local health centres.  

Nigeria has recently been hit by outbreaks of Lassa fever, with more than 150 deaths recorded across the nation since January.

The rodent-borne disease is thought to cause no symptoms in 80 per cent of patients and kill just one per cent of those it infects. 

People usually become infected with Lassa fever after exposure to food or household items contaminated with urine or faeces of infected rats.

But the virus, which can make women bleed from their vagina and trigger seizures, can also be transmitted via bodily fluids.

Last year, the country also battled a deadly diphtheria outbreak, killing more than 600 people mainly children. 

The highly contagious bacterial infection mainly affects the nose and throat. It can also infect the skin, causing painful lesions.