Lassa fever deaths: WHO report on late diagnosis in Nigeria found inaccurate

A report by the World Health Organisation which claimed late diagnosis has accounted for the high death rates from Lassa fever has been discountenanced and considered baseless by virology experts in Nigeria, BusinessDay findings reveal.

WHO had reported that the Lassa fever scourge which has killed 167 people in West Africa, claimed more lives in Nigeria, since November 2015, with Nigeria, Benin, Sierra Leone, Liberia and Togo reporting more than 300 cases of Lassa fever.

“Nigeria accounts for the majority of the cases with 266 cases and 138 deaths reported in 22 of the country’s 34 provinces as at 21 March 2016. Benin has recorded 51 cases and 25 deaths. Togo and Sierra Leone each reported 2 cases. More recently, since February, Liberia has reported seven confirmed cases including 3 deaths,” reports WHO

WHO asserted that many of these lives could have been saved if rapid diagnostic tests were available so that people could receive treatment early.

Experts however disagree with the verdict by WHO in indicting Nigeria for high mortality as they explain that late reporting by patients has been the cause of death rates recorded. They explain that tests are promptly carried out, and care giving is commenced quickly, against the impression WHO has tried to portray of the country.

Abdulsalami Nasidi, Director General of the Nigerian Centre for Disease Control (NCDC) while responding to BusinessDay enquiries said “We had informed the nation through the Honourable Minister that LATE PRESENTATION to medical centres and the possibility that the virus might have become more virulent could have contributed to high mortality.  We have also observed in some instances evidence of virus resistance to Ribavirin which our group is currently studying. This could also contribute to high mortality.”

“We should mind the choice of words, late reporting or late diagnosis?” Sunday Omilabu, a professor of virology and former chairman of presidential taskforce on Lassa fever, asks rhetorically.

Omilabu tells BusinessDay that; “If they don’t report on time, there is nothing for the lab to diagnose. It is late reporting to the health facilities that contributed to that high fatality. Prompt diagnosis is done and we generate results under 24 hours, maximally.”

“Some communities mention spiritual attack and for that reason did not believe it is a medical issue. Niger state for instance lost a number of victims before the ministry of health was alerted,” Omilabu adds.

David Olaleye, a professor and Head of Virology department in the University of Ibadan also disagreed with the position by WHO, saying the reason given may not be a complete explanation.

According to Olaleye, “In disease control, the protocol is that once there is an outbreak of a particular disease, after establishing the epidemic to be Lassa, subsequent cases that are symptomatically similar to hemorrhagic fever should be treated as a case of Lassa.”

“It is wrong for anybody to wait until there is laboratory confirmation. I do not know anywhere in the developing world where such requirement can be met. This is different from other diseases such as HIV. It has been proven that we have a case of Lassa on our hands, so why should anybody wait for laboratory confirmation before treatment (especially with Ribavirin) commences on symptomatic cases?” Olayele stated rhetorically.

The need for government to focus more on funding healthcare research to meet the challenges of different epidemic outbreak was also emphaised, as Olaleye observed that whenever there are disease outbreaks in Nigeria, foreign donor agencies are relied upon to rise to the occasion. This, Olaleye says has led to short span of attention in combating diseases because these donors move to another funding program whenever there is a new outbreak.

It has also been revealed that the strain of Lassa fever virus may have mutated from what was first analysed in 1969 when the virus was first discovered. This according to experts may negate the potentials of medication such as Ribavirin in effectively combating the virus.

“It is normal for the virus to mutate. The virus parades two genes and each of the genes must be replicated in the daughter virus. Once there is a replication they must come up with new set of progenies. So, the virus mutates over time. What we know is that we have lineages; about 5 lineages of the virus. 3 are in Nigeria and 2 in other West African countries; Liberia and Sierra Leone. Even at that level, we have changes within the lineages. It is a possibility that some strains cannot be effectively attacked by Ribavirin,” Omilabu said.

Lassa fever or Lassa hemorrhagic fever (LHF) is an acute viral hemorrhagic fever caused by the Lassa virus and first described in 1969 in the town of Lassa, in Borno State, Nigeria.

Lassa virus is carried by the Mastomys rat, which is found in parts of West Africa. The virus is transmitted to humans from direct contact with infected rats by catching and preparing them for food, or through contact with food or household items contaminated with rat faeces or urine. The virus can also be transmitted through contact with an infected person’s body fluids.

According to WHO, around 80% of people who become infected with Lassa virus have no symptoms or they have symptoms that mimic other illnesses, such as malaria, making it difficult to treat them. Symptoms include fever, fatigue, nausea, vomiting, diarrhoea, headaches, abdominal pains, sore throat and facial swelling.

Caleb Ojewale