Nigeria recorded 12 new laboratory-confirmed cases of Lassa fever between December 26, 2022 and January 1, 2023, according to the Nigeria Centre for Disease Control and Prevention (NCDC).

The 12 new cases were from three states of the federation as follows: Edo (9), Ebonyi (2), and Benue (1).

The NCDC, in its 52nd-week report covering December 26, 2022 to January 1, 2023, stated that there were 8,202 suspected cases of Lassa fever in the country as at January 1, with 1,067 confirmed cases across 112 local government areas and 27 states, while the death toll was put at 189 with a Case Fatality Rate (CFR) of 17.7 percent. A total of 63 healthcare workers were infected by the disease within the period under review, it said.

As of Wednesday, January 11, the confirmed cases of Lassa fever in Edo State had risen to 26. Prof. Obehi Akoria, Edo State Commissioner for Health, told journalists in Benin City that the 26 confirmed cases, including 10 adult males, nine females, and seven children, were receiving medical care at the Irrua Specialist Teaching Hospital (ISTH) in the state, and that they “are all stable and responding to treatment”.

The Commissioner also charged residents to observe preventive measures against the spread of Lassa fever to protect themselves and their loved ones from the disease.

Prof. Akoria reassured that Lassa fever, a viral illness caused by the Lassa virus and transmitted to humans through contact with the urine or faeces of infected rats, or through direct contact with the blood, urine, semen, or breast milk of infected humans, is preventable.

“The symptoms of Lassa fever include fever, headache, malaise, weakness, muscle pain, chest pain, sore throat, vomiting, and diarrhea, as well as hemorrhage in severe cases,” she said.

To prevent further spread of Lassa fever, Prof Akoria encouraged residents to avoid bush burning, indiscriminate waste disposal, and maintain high standards of communal hygiene. She also implored healthcare providers to desist from managing illnesses beyond their scope and to promptly refer such cases as early treatment is key to survival and containing spread.

In addition to Prof Akoria’s advice, below is a guide to Lassa fever prevention according to the World Health Organisation (WHO).

WHO’s guide to Lassa prevention

According to the WHO, Lassa fever prevention relies heavily on promoting good “community hygiene” in order to discourage rodents from entering homes.

“Effective measures include storing grain and other foodstuffs in rodent-proof containers, disposing of garbage far from the home, maintaining clean households and keeping cats.

“Because Mastomys are so abundant in endemic areas, it is not possible to completely eliminate them from the environment. Family members should always be careful to avoid contact with blood and body fluids while caring for sick persons,” the world health agency said.

Apart from transmission to humans via contact with food or household items contaminated with rodent urine or faeces, the specialised UN agency responsible for international public health warns that person-to-person infections and laboratory transmission can also occur, particularly in hospitals lacking adequate infection prevention and control measures.

Therefore, in order to prevent this, it advised that health-care staff should always apply standard infection prevention and control precautions when caring for patients, regardless of their presumed diagnosis.

“These include basic hand hygiene, respiratory hygiene, use of personal protective equipment (to block splashes or other contact with infected materials), safe injection practices and safe burial practices,” the WHO said.

“Health-care workers caring for patients with suspected or confirmed Lassa fever should apply extra infection control measures to prevent contact with the patient’s blood and body fluids and contaminated surfaces or materials such as clothing and bedding. When in close contact (within 1 metre) of patients with Lassa fever, health-care workers should wear face protection (a face shield or a medical mask and goggles), a clean, non-sterile long-sleeved gown, and gloves (sterile gloves for some procedures),” it said.

The world health agency said laboratory workers are also at risk and advised that samples taken from humans and animals for investigation of Lassa virus infection should be handled by trained staff and processed in suitably equipped laboratories under maximum biological containment conditions.

“On rare occasions, travellers from areas where Lassa fever is endemic export the disease to other countries. Although malaria, typhoid fever, and many other tropical infections are much more common, the diagnosis of Lassa fever should be considered in febrile patients returning from West Africa, especially if they have had exposures in rural areas or hospitals in countries where Lassa fever is known to be endemic. Health-care workers seeing a patient suspected to have Lassa fever should immediately contact local and national experts for advice and to arrange for laboratory testing,” the WHO said.

Once a patient has been infected with the Lassa fever virus, the WHO advised early supportive care with rehydration and symptomatic treatment to improve survival.