Nigeria in War against Lassa fever

To escape the current acute viral illness called Lassa fever ravaging Nigeria, avoid any exposure to rats.

The Ministry of Health aptly captures the reality of the situation in Nigeria, where official figures as at Friday put the number of death resulting from contacting the fever at 40 and the cases at 85 within the last six weeks.  The virus has reportedly spread to 10 states. 

The ailment which ‘originated’ in the country about 47 years could resurface again, despite advancement in medicine, shows that Nigeria’s healthcare system is weak in disease prevention and control.

The death percentage attributed to Lassa fever is currently put at 43.2 per cent, a rate considered very high by all standards.
Fact sheets released by the United States Centre for Disease Prevention and Control (US CDC) indicate that Lassa virus is carried by rats and spread to humans through contact with urine or droppings of infected rats in West Africa. 

The document explains that, in rare cases, the ailment could be spread from person to person through direct contact with a sick person’s blood or body fluids, but there is no record of transmission through casual contact. 

The illness reportedly was discovered in 1969 when two missionary nurses died in Nigeria. The virus is thus named after Lassa, a village in Borno State in the North East where the first cases occurred.

According to statistics, there has been gradual decline of cases of Lassa fever in Nigerian between 2011 and 2015. The cause of the marked reduction in 2015 is not known, he said.

“However, the dry season of 2014/2015 was shorter and Nigeria was still in the sustenance phase of Ebola control when suspicion of haemorrhagic fever was high across the country.

“The fatality recorded in 2016 so far is the highest in 5 years. It is a surge in fatality. Given the periodic occurrences of this disease, Nigeria must demonstrate better preparedness in the future.”

Though the number of Lassa virus infections per year in West Africa is estimated at 100,000 to 300,000, with approximately 5,000 deaths, the CDC describes this as ‘crude’. 

“Such estimates are crude, because surveillance for cases of the disease is not uniformly performed.”
The Nigerian government expressed its embarrassment over the outbreak of the disease again, but has reassured Nigerians that the challenge would soon come to an end and said 10 states has so far experienced it in the last 6 weeks.  

According to him, the states affected include Bauchi, Nassarawa, Niger, Taraba, Kano, Rivers, Edo, Plateau, Gombe and Oyo States.  The total number so far reported is 86 and 40 deaths, with a mortality rate of 43.2 percent.

“Our laboratories have confirmed 17 cases, indicative of a new round-trip of Lassa fever outbreak.

“The first case of the current outbreak was reported from Bauchi in November, 2015. This was followed by cases reported by Kano State, and subsequently, the other states mentioned above.

The reservoir or host of the Lassa virus is the ‘multimammate rat’ called Mastomys natalensis which has many breasts and lives in the bush and peri-residential areas.

“The virus is contained in the urine and droppings of the rats, and can be transmitted through direct contact, touching objects or eating food contaminated with these materials or through cuts or sores.”

Nosocomial transmission also occurs in health facilities where infection prevention and control practices are not observed. Person to person transmission also occurs most especially when a person comes in contact with the virus in the blood, tissue, secretions or excrements of an infected individual.

In response to the reported outbreaks, Ministry of health has immediately released adequate quantities of ribavirin, the specific antiviral drug for Lassa fever to all the affected states for prompt and adequate treatment of cases; deployed rapid response teams from the Ministry to all the affected states to assist in investigating and verifying the cases as well as tracing of contacts.

The ministry stressed: “Clinicians and relevant healthcare workers had been sensitized and mobilized in areas of patient management and care in the affected states. Affected States have been advised to intensify awareness creation on the signs and symptoms including preventive measure such as general hygiene. 

“Furthermore, it is important to note that Nigeria has the capability to diagnose Lassa fever. All the cases reported so far were confirmed by our laboratories.

However, due to the non-specific nature of Lassa fever symptoms and varied presentations, clinical diagnosis is often difficult and delayed, especially in the early course of the disease outbreak.” 

His words: “ In addition, health educational materials were distributed to all States, particularly the affected areas for effective health promotion to enhance good “community hygiene” including food hygiene and food protection practices.   I urge all to ensure that they avoid contact with rodents/rats as well as food/objects contaminated with rats’ secretions/excretions.” 

He urged people to avoid drying food in the open and along the roadside. He also advised people to cover all food to prevent rodents’ contamination. All suspected cases are to be reported immediately to enable early treatment.

“Family members and health care workers are advised to always be careful and avoid contact with blood and body fluids while caring for sick persons with symptoms similar to those listed for Lassa fever and any such patients should be taken to nearest health facility.

“All health facilities in the country are hereby directed to emphasize routine infection prevention and control measures, and ensure that all patients are treated free. Additionally, all health care workers should have a high index of suspicion of Lassa fever in patients presenting with febrile illnesses particularly in endemic states, and all suspected cases should be reported to NCDC/FMOH and the State Epidemiologists. 

“On the basis of the effective control measures now instituted by the FMOH, no travel restrictions will be imposed from and to areas currently affected.

“Healthcare workers seeing a patient suspected to have Lassa fever should immediately contact the State Epidemiologist in the state ministry of health or call the Nigeria Centre for Disease Control and Federal Ministry of Health using the following numbers: 08093810105, 08163215251, 08031571667 and 08135050005.To support States and minimize impact and reduce mortality FMOH has procured and distributed additional Ribavirin for immediate treatment purposes and creation of strategic stock for future possible cases.”

He reiterated that the World Health Organization (WHO) was being notified of the cases confirmed. The Nigeria Centre for Disease Control (NCDC), he noted, is already coordinating all Nigeria’s response activities and reporting to the Minister on daily basis. 

He added:  “The Nigerian Government will continue to enhance its surveillance and social health education, information and communication activities to prevent the disease from spreading further in Nigeria.” 

The Minister was, however, failed to convincingly reel out methods to be adopted to strengthen the nation’s disease surveillance system against future invasion of this ailment couriered by rats.  

Indeed, President of the Nigerian Academy of Science (NAS), Prof Oyewale Tomori, is worried that Nigeria has not taken surveillance system serious in its efforts to curb Lassa fever.

He heaped the blame for the resurgence of Lassa fever on Nigeria’s nation’s weak surveillance system, poor funding of epidemiology studies, inadequate diagnostic centres and poor awareness of the disease among Nigerians. 

Tomori added that Nigeria’s lackadaisical attitude towards monitoring and analysis of Lassa fever data has reflected in its poor drive to create awareness for the disease among Nigerians.

For instance, he pointed out the epidemiology departments in the nation’s Ministries of Health were under underfunded, a situation he said had undermined their ability to spot and alert Nigerians of the disease on time.

Tomori, who was the Regional Virologist for the WHO Africa Region, explained that with strong monitoring and reporting system, Nigeria would have been able to curb the yearly outbreak of the fever, even as he explained that the viral disease mostly occurs in dry season when mastomys rodents, the special rodents that host the virus, would have colonised homes in search of food. 

Tomori added that one of the problems facing Nigeria in the fight against Lassa fever has been poor funding of the few available diagnostic laboratories, adding that the three best diagnostic laboratories established to detect the disease are located in Ogun, Lagos and Edo states (all in Southern Nigeria) with heavy financial support from some Western nations. 

Tomori said: “The other diagnostic laboratories owned by the Federal Government cannot function very well because there is no support from outside. These labs are there, but they are not well funded. But at least, government pays the staff salaries. When you have a person who is well trained, but you not given him reagents, he is as good as useless. I am sure that in about six or nine months, he cannot even remember the training he had because he did not practice it. This is a major problem we have in these other places; they do not have reagents to function. We have said it 200 times, but nobody listens to us

Signs and symptoms

In 80 per cent of this cases, the disease is asymptomatic, but in the remaining 20 per cent, it takes a complicated course.

The symptoms of Lassa fever typically occur one to three weeks after the patient comes into contact with the virus. These include fever, retrosternal pain (pain behind the chest wall), sore throat, back pain, cough, abdominal pain, vomiting, diarrhea, conjunctivitis, facial swelling, proteinuria (protein in the urine), and mucosal bleeding. Neurological problems have also been described, including hearing loss, tremors, and encephalitis.

Clinically, Lassa fever infections are difficult to distinguish from other viral hemorrhagic fevers such as Ebola and Marburg, and from more common febrile illnesses such as malaria.

The virus is excreted in urine for three to nine weeks and in semen for three months.

According to the Minister of Health, the first case of the current outbreaks was reported from Bauchi State in November 2015, followed by cases reported by Kano State and subsequently the other six states. Indeed, Nigeria has been experiencing Lassa fever outbreak in the past six weeks in Bauchi, Nasarawa, Niger, Taraba, Kano, Rivers, Edo and Oyo states.

Meanwhile, the Federal Government said measures had been put in place to curtail further spread and reduce mortality among those affected, however, ruled out placing travel restrictions from and to areas currently affected.

Some of these viruses belong to a group that causes similar diseases like yellow fever, which for 18 years now, we have not had a single case, but 18 years ago it devastated Nigeria.

“It is also the cause of what is called haemorrhagic fever, then Lassa fever which you know has been ongoing. There are even parts of Nigeria where it is endemic like the northern part of Edo State; they record a case every week and it is also very deadly.”

THE CHALLENGES AND GAPS

According to the WHO, in the early stages, Lassa fever is often misdiagnosed as influenza, typhoid or malaria, and as a result many patients fail to receive appropriate medical treatment. Making a correct diagnosis of Lassa fever is made difficult by the wide spectrum of clinical effects that manifest, ranging from asymptomatic to multi-organ system failure and death. The onset of the illness is typically indolent, with no specific symptoms that would distinguish it from other febrile illnesses. Early signs include fever, headache and general malaise, followed by a sore throat, nausea, vomiting, abdominal pain and diarrhea in some cases. After four to seven days, many patients will start to feel better, but a small minority will proceed to display symptoms such as edema, hypertension, bleeding and shock. Death from Lassa fever most commonly occurs 10 to 14 days after symptom onset.

Meanwhile, Nigeria had through November 6, 2015, reported 270 Lassa fever cases from 12 states, according to data from Nigerian health officials. According to the Nigeria Centre for Disease Control (NCDC), two Lassa fever deaths were reported in Kano State, last month.

A nationwide outbreak of Lassa fever in the 10 states, in March 2014, had killed at least 20 people with about 319 reported cases.

The affected states were Anambra, Bauchi, Ebonyi, Edo, Gombe, Imo, Nasarawa, Ondo, Plateau and Taraba.

The Lassa virus was first described in 1969 in the town of Lassa, in Borno State, Nigeria.

According to the United States Centers for Disease Control and Prevention (CDC), Lassa fever is an acute viral illness that occurs in West Africa. The virus, a member of the virus family Arenaviridae, is a single-stranded RNA virus and is zoonotic, or animal-borne.

NIGERIA ALERTS RESIDENTS

Meanwhile, worried about the outbreak of Lassa fever in some parts of Nigeria leaving many dead and others hospitalized, Ministry of Health has alerted residents on how to protect their lives and those of others around them.

Ministry of Health in a public alert last week noted that Lassa fever is caused by infection with the Lassa virus, which is spread by rats that live in large numbers in West, Central, and East Africa. They carry the virus in their urine and faeces and live in homes and areas where food is stored.

The ministry said people should suspect Lassa fever in persons who present above symptoms with a positive history of being in contact with a suspected or infected person or health worker who had treated either suspected or confirmed infected person.

PREVENTION AND TREATMENT OF LASSA FEVER

However, Lassa fever could be treated. Antiviral drugs have been used successfully to treat Lassa fever. The earlier a person presents, the better the outcome of treatment.

For prevention and control of Lassa fever, the ministry OF health have urged the general public to:
*Avoid contact between rats and human beings.
*Observe good personal hygiene including hand washing with soap and running water regularly
*Disposal of waste properly and cleaning of the environment so that rats are not attracted
*Store foods in rat proof containers and cook all foods thoroughly before eating.
*Discourage rodents from entering the house by blocking all possible entry points
*For food manufacturers and handlers, do not spread food where rats can have access to it.
*The public should also report any cases of above symptoms or persistent high fever not responding to standard treatment for malaria and typhoid fever to the nearest health center.
*All fluids from an infected person are extremely dangerous. Health workers are also advised to be at alert, wear personal protective equipment, observe universal basic precautions, nurse suspected cases in isolation and report same to the Local Government Area (LGA) or Ministry of Health immediately.