Lassa Fever in Post-Conflict Sierra Leone

Background

Lassa fever (LF), an often-fatal hemorrhagic disease caused by Lassa virus (LASV), is a major public health threat in West Africa. When the violent civil conflict in Sierra Leone (1991 to 2002) ended, an international consortium assisted in restoration of the LF program at Kenema Government Hospital (KGH) in an area with the world''s highest incidence of the disease.

Methodology/Principal Findings

Clinical and laboratory records of patients presenting to the KGH Lassa Ward in the post-conflict period were organized electronically. Recombinant antigen-based LF immunoassays were used to assess LASV antigenemia and LASV-specific antibodies in patients who met criteria for suspected LF. KGH has been reestablished as a center for LF treatment and research, with over 500 suspected cases now presenting yearly. Higher case fatality rates (CFRs) in LF patients were observed compared to studies conducted prior to the civil conflict. Different criteria for defining LF stages and differences in sensitivity of assays likely account for these differences. The highest incidence of LF in Sierra Leone was observed during the dry season. LF cases were observed in ten of Sierra Leone''s thirteen districts, with numerous cases from outside the traditional endemic zone. Deaths in patients presenting with LASV antigenemia were skewed towards individuals less than 29 years of age. Women self-reporting as pregnant were significantly overrepresented among LASV antigenemic patients. The CFR of ribavirin-treated patients presenting early in acute infection was lower than in untreated subjects.

Conclusions/Significance

Lassa fever remains a major public health threat in Sierra Leone. Outreach activities should expand because LF may be more widespread in Sierra Leone than previously recognized. Enhanced case finding to ensure rapid diagnosis and treatment is imperative to reduce mortality. Even with ribavirin treatment, there was a high rate of fatalities underscoring the need to develop more effective and/or supplemental treatments for LF.     

Species diversity and seasonal abundance in Charaxes butterflies (Nymphalidae)

Species diversity in Charaxes butterflies trapped in gardens at Freetown, Sierra Leone, is calculated by two different methods. There is little evidence of seasonal changes in diversity and in abundance.     

No Evidence for Lymphatic Filariasis Transmission in Big Cities Affected by Conflict Related Rural-Urban Migration in Sierra Leone and Liberia

Background

In West Africa, the principal vectors of lymphatic filariasis (LF) are Anopheles species with Culex species playing only a minor role in transmission, if any. Being a predominantly rural disease, the question remains whether conflict-related migration of rural populations into urban areas would be sufficient for active transmission of the parasite.

Methodology/Principal Findings

We examined LF transmission in urban areas in post-conflict Sierra Leone and Liberia that experienced significant rural-urban migration. Mosquitoes from Freetown and Monrovia, were analyzed for infection with Wuchereria bancrofti. We also undertook a transmission assessment survey (TAS) in Bo and Pujehun districts in Sierra Leone. The majority of the mosquitoes collected were Culex species, while Anopheles species were present in low numbers. The mosquitoes were analyzed in pools, with a maximum of 20 mosquitoes per pool. In both countries, a total of 1731 An. gambiae and 14342 Culex were analyzed for W. bancrofti, using the PCR. Two pools of Culex mosquitoes and 1 pool of An. gambiae were found infected from one community in Freetown. Pool screening analysis indicated a maximum likelihood of infection of 0.004 (95% CI of 0.00012–0.021) and 0.015 (95% CI of 0.0018–0.052) for the An. gambiae and Culex respectively. The results indicate that An. gambiae is present in low numbers, with a microfilaria prevalence breaking threshold value not sufficient to maintain transmission. The results of the TAS in Bo and Pujehun also indicated an antigen prevalence of 0.19% and 0.67% in children, respectively. This is well below the recommended 2% level for stopping MDA in Anopheles transmission areas, according to WHO guidelines.

Conclusions

We found no evidence for active transmission of LF in cities, where internally displaced persons from rural areas lived for many years during the more than 10 years conflict in Sierra Leone and Liberia.     

Progress in controlling the reinvasion of windborne vectors into the western area of the Onchocerciasis Control Programme in West Africa

Since vector control began in 1975, waves of Simulium sirbanum and S. damnosum s.str., the principal vectors of severe blinding onchocerciasis in the West African savannas, have reinvaded treated rivers inside the original boundaries of the Onchocerciasis Control Programme in West Africa. Larviciding of potential source breeding sites has shown that these 'savanna' species are capable of travelling and carrying Onchocerca infection for at least 500 km northeastwards with the monsoon winds in the early rainy season. Vector control has, therefore, been extended progressively westwards. In 1984 the Programme embarked on a major western extension into Guinea, Sierra Leone, western Mali, Senegal and Guinea-Bissau. The transmission resulting from the reinvasion of northern C?te d'Ivoire and Burkina Faso has been reduced by over 95%, but eastern Mali has proved more difficult to protect because of sources in both Guinea and Sierra Leone. Rivers in Sierra Leone were treated for the first time in 1989 and biting and transmission rates in Sierra Leone and Guinea fell by over 90%. Because of treatment problems in some complex rapids and mountainous areas, flies still reinvaded Mali, though biting rates were approximately 70% lower than those recorded before anti-reinvasion treatments started. It was concluded that transmission in eastern Mali has now been reduced to the levels required to control onchocerciasis.     

IV.–Field-notes on the Birds of Sierra Leone.

T he following notes were mostly made during twelve months' service in Sierra Leone, West Africa, 1921-22, of which nine and a half months were passed at Freetown and two and a half in the hinterland. During this latter period I had, however, not much time for observation, as I was travelling daily. My route was a circular one, from Freetown to Port Lokko by canoe, thence to Mabanta, and eastward from there to about the centre of the Panguma District; northward to Falaba, thence westward and southward through the Kariua District back to Port Lokko. Although all my collecting was done, and most of my notes made during the twelve months above referred to, I had had two previous tours of service in this country, and observations made then have helped to confirm some of my conclusions. Ornithology was the recreation of my spare time, which was of course limited.     

Human immunodeficiency virus type 2 (HIV-2) seroprevalence and characterization of a distinct HIV-2 genetic subtype from the natural range of simian immunodeficiency virus-infected sooty mangabeys.

The extent of zoonotic infections in rural Sierra Leone, where both feral and pet sooty mangabeys harbor divergent members of the human immunodeficiency virus type 2 (HIV-2)-sooty mangabey simian immunodeficiency virus (SIVsm) family, was tested in blood samples collected from 9,309 human subjects in 1993. Using HIV-1- and HIV-2-specific enzyme immunoassays and confirmatory Western blot analysis to test for antibodies to SIVsm-related lentiviruses, we found only nine subjects (0.096%) who tested positive for HIV: seven tested positive for HIV-1 and two tested positive for HIV-2. Compared with other rural West African communities, Sierra Leone displayed the lowest seroprevalence (0.021%) of HIV-2 infection yet reported, much lower than the previously reported seroprevalence in SIVsm-infected feral and household pet sooty mangabeys. Heteroduplex analysis demonstrated that two of the newly found HIV-1 strains belonged to subtype A, the most common HIV-1 subtype in Africa, but this is the first report of subtype A in Sierra Leone. The two HIV-2-infected individuals harbored two distinct HIV-2 strains, designated 93SL1 and 93SL2. Phylogenetic analysis indicated that HIV-2 93SL1 is a member of HIV-2 subtype A, the first strain of this HIV-2 subtype found in Sierra Leone. In contrast, HIV-2 93SL2 belongs to none of the five previously characterized HIV-2 subtypes (A to E) but is a new subtype, herein designated F, having the most divergent transmembrane sequences yet reported for HIV-2. The fact that both of the two most divergent HIV-2 subtypes known, E and F, are rare and found as single occurrences in persons from Sierra Leone may be related to the fact that this small region of West Africa also contains free-living and household pet sooty mangabeys with highly divergent variants of SIVsm. This finding provides support for the hypotheses that new HIV-2 subtypes result from independent cross-species transmission of SIVsm to the human population and that these single-occurrence transmission events had not spread widely into the population by 1993.     

Factors Associated with HIV Prevalence and HIV Testing in Sierra Leone: Findings from the 2008 Demographic Health Survey

BackgroundThe Sierra Leone Demographic Health Survey 2008 found an HIV prevalence of 1.5%. This study investigates associations with HIV infection and HIV testing.MethodsHouseholds were selected using stratified multi-stage sampling. In all selected households women aged 15–49 were eligible. In every second household men aged 15–59 were also eligible. Participants were asked to consent for anonymous HIV testing. All participants interviewed and tested were analysed. Multiple logistic regression identified associations with HIV infection, undiagnosed infection and with ever having a voluntary HIV test among sexually active participants.ResultsOf 7495 invited 86% (6,475) agreed to an interview and HIV test. Among 96 HIV positive participants, 78% had never taken a voluntary HIV test so were unaware of their serostatus, and 86% were sexually active in the last 12 months among whom 96% did not use a condom at last intercourse. 11% of all participants had previously voluntarily tested. Among women who had tested, 60% did so in antenatal care. We found that those living in an urban area, and those previously married, were more likely to be HIV infected. Voluntary HIV testing was more common in those aged 25–44, living in an urban area, females, having secondary or higher education, having first sexual intercourse at age 17 years or older, and using condoms at last sex. Although 82% of men and 69% of women had heard of HIV, only 35% and 29% respectively had heard of antiretroviral therapy.ConclusionsThe HIV prevalence in Sierra Leone has been stable. HIV testing, however, is uncommon and most infected individuals are unaware of their serostatus. This could allow the epidemic to escalate as individuals with undiagnosed infection are unlikely to change their behaviour or access treatment. Improving knowledge and increasing testing need to remain central to HIV prevention interventions in Sierra Leone.     

Is There a Political Ecology of the Sierra Leonean Landscape?

Corruption and State Politics in Sierra Leone. William Reno. Cambridge: Cambridge University Press, 1995. 229 pp.
Fighting for the Rain Forest: War, Youth and Resources in Sierra Leone. Paul Richards. Portsmouth, NH: Heinemann, 1996. 182 pp.
Myth and Reality in the Rain Forest: How Conservation Strategies Are Failing in West Africa. John F. Oates. Berkeley: University of California Press, 1999. 310 pp.     

Epidemic of acute haemorrhagic conjunctivitis in Freetown, Sierra Leone, in 1970

Epidemiological features of the epidemic of acute haemorrhagic conjunctivitis in Freetown, Sierra Leone, in 1970, are described. On the basis of hospital figures and a House-to -House survey of 0.9% of the population it is estimated that 50-53% of Freetown's population suffered from the conjunctivitis in 20 weeks. Though no causative agent was isolated, it is supposed, on the basis of the striking similarity with other outbreaks, that the epidemic was caused by enterovirus type 70. Hospital figures, a house-to-house survey and a survey in a closed community provided evidence that man-to-man contact was the principal mode of spread.     

Viral infections in travellers from tropical Africa.

Examination of sera from 86 travellers to Britain from tropical Africa disclosed evidence of past infection with 10 identifiable viruses, of which the most important were O''nyong-nyong, dengue, chikungunya, and Ntaya. The findings indicate that infection with O''nyong-nyong may be acquired sporadically in Nigeria, Ghana, and Sierra Leone, where it has not previously been identified. Chikungunya infection had not been recorded in West Africa other than Nigeria and Senegal. Patients from Sierra Leone and contiguous Liberia had antibodies to this infection. An outbread of dengue fever in the Seychelles in early 1977 was confirmed. Ntaya virus, though known in Uganda, Cameroon, and Zaire, appears also to be transmitted in Kenya, Nigeria, and Zambia. Clinical studies indicated that chikungunya infection may present with alimentary features, possibly with jaundice. The clinical features of Ntaya infection may include kizarre neurological manifestations in addition to fever. The absence of Lassa antibodies among these travellers suggested that this infection is not a common hazard among such persons.     

Chronic wounds in Sierra Leone: Searching for Buruli ulcer,a NTD caused by Mycobacterium ulcerans,at Masanga Hospital

BackgroundChronic wounds pose a significant healthcare burden in low- and middle-income countries. Buruli ulcer (BU), caused by Mycobacterium ulcerans infection, causes wounds with high morbidity and financial burden. Although highly endemic in West and Central Africa, the presence of BU in Sierra Leone is not well described. This study aimed to confirm or exclude BU in suspected cases of chronic wounds presenting to Masanga Hospital, Sierra Leone.MethodologyDemographics, baseline clinical data, and quality of life scores were collected from patients with wounds suspected to be BU. Wound tissue samples were acquired and transported to the Swiss Tropical and Public Health Institute, Switzerland, for analysis to detect Mycobacterium ulcerans using qPCR, microscopic smear examination, and histopathology, as per World Health Organization (WHO) recommendations.FindingsTwenty-one participants with wounds suspected to be BU were enrolled over 4-weeks (Feb-March 2019). Participants were predominantly young working males (62% male, 38% female, mean 35yrs, 90% employed in an occupation or as a student) with large, single, ulcerating wounds (mean diameter 9.4cm, 86% single wound) exclusively of the lower limbs (60% foot, 40% lower leg) present for a mean 15 months. The majority reported frequent exposure to water outdoors (76%). Self-reports of over-the-counter antibiotic use prior to presentation was high (81%), as was history of trauma (38%) and surgical interventions prior to enrolment (48%). Regarding laboratory investigation, all samples were negative for BU by microscopy, histopathology, and qPCR. Histopathology analysis revealed heavy bacterial load in many of the samples. The study had excellent participant recruitment, however follow-up proved difficult.ConclusionsBU was not confirmed as a cause of chronic ulceration in our cohort of suspected cases, as judged by laboratory analysis according to WHO standards. This does not exclude the presence of BU in the region, and the definitive cause of these treatment-resistance chronic wounds is uncertain.     

Mitochondrial DNA genetic diversity among four ethnic groups in Sierra Leone

Although there are numerous ethnic groups in Sierra Leone, the Mende and Temne together account for approximately 60% of the total population. To see if genetic differences could be observed among ethnic groups in Sierra Leone, the nucleotide sequence of the hypervariable 1 (HV1) region of mitochondrial DNA (mtDNA) was determined from samples of the two major ethnic groups, the Mende (n=59) and Temne (n=121), and of two minor ethnic groups, the Loko (n=29) and Limba (n=67). Among these 276 HV1 sequences, 164 individual haplotypes were observed. An analysis of molecular variance indicated that the distribution of these haplotypes within the Limba sample was significantly different from that of the other ethnic groups. No significant genetic variation was seen between the Mende, Temne, and Loko. These results indicate that distinguishing genetic differences can be observed among ethnic groups residing in historically close proximity to one another. Furthermore, we observed some mitochondrial DNA haplotypes that are common among the Sierra Leone ethnic groups but that have not been observed in other published studies of West African ethnic groups. Therefore, we may have evidence for mtDNA lineages that are unique to this region of West Africa.     

The Impact of the West Africa Ebola Outbreak on Obstetric Health Care in Sierra Leone

Background

As Sierra Leone celebrates the end of the Ebola Virus Disease (EVD) outbreak, we can begin to fully grasp its impact on already weak health systems. The EVD outbreak in West Africa forced many hospitals to close down or reduce their activity, either to prevent nosocomial transmission or because of staff shortages. The aim of this study is to assess the potential impact of EVD on nationwide access to obstetric care in Sierra Leone.

Methods and Findings

Community health officers collected weekly data between January 2014—May 2015 on in-hospital deliveries and caesarean sections (C-sections) from all open facilities (public, private for-profit and private non-profit sectors) offering emergency obstetrics in Sierra Leone. This was compared to official data of EVD cases per district. Logistic and Poisson regression analyses were used to compute risk and rate estimates. Nationwide, the number of in-hospital deliveries and C-sections decreased by over 20% during the EVD outbreak. The decline occurred early on in the EVD outbreak and was mainly attributable to the closing of private not-for-profit hospitals rather than government facilities. Due to difficulties in collecting data in the midst of an epidemic, limitations of this study include some missing data points.

Conclusions

Both the number of in-hospital deliveries and C-sections substantially declined shortly after the onset of the EVD outbreak. Since access to emergency obstetric care, like C-sections, is associated with decreased maternal mortality, many women are likely to have died due to the reduced access to appropriate care during childbirth. Future research on indirect health effects of health system breakdown should ideally be nationwide and continue also into the recovery phase. It is also important to understand the mechanisms behind the deterioration so that important health services can be reestablished.     

The reproductive biology of the White-necked Picathartes Picathartes gymnocephalus

The reproductive biology of the White-necked Picathartes Picathartes gymnocephalus , a threatened species endemic to the Upper Guinea rainforest of West Africa, was studied in Sierra Leone from 1990 to 1996. The modal clutch size was two (mean 1.92) eggs. Incubation averaged 20 days and the nestling period 25 days. Nesting success (probability of eggs laid surviving to fledge) was 22.9%. Only 0.44 chicks fledged per nesting pair. The main known causes of nest mortality were predation and infanticide. Nestlings fledged when almost 30% smaller than adult size. A life-table indicates that populations in Sierra Leone could be declining slowly. Alternatively, White-necked Picathartes could be very long-lived (annual adult survival could be greater than 90%), in which case populations would be self-sustaining.     

‘Black’ and ‘white’ death: burials in a time of Ebola in Freetown,Sierra Leone

The article examines experiences of the 2014‐15 Ebola crisis in Freetown, Sierra Leone, through an analysis of the performance of burials. While most of the city's residents had no contact with the virus, ‘Ebola’ was inescapable, owing to the onerous state of emergency regulations imposed by national and international authorities. All burials, regardless of the cause of death, were to be performed by newly established official teams operating according to unfamiliar biomedical and bureaucratic protocols. Burials became emblematic of the crisis through presenting a conflict between local practices and novel procedures, which was coded locally in a complex racial language of ‘black’ and ‘white’, recalling a long regional history of violent integration into the Atlantic World. Building on long‐standing anthropological discussion on the relationship between ‘good’ death and social order, the article explores how burials became sites around which opposing ‘orders’ were experienced, negotiated, and reconciled in locally meaningful ways.     

Assessment of Environmental Contamination and Environmental Decontamination Practices within an Ebola Holding Unit,Freetown, Sierra Leone

Evidence to inform decontamination practices at Ebola holding units (EHUs) and treatment centres is lacking. We conducted an audit of decontamination procedures inside Connaught Hospital EHU in Freetown, Sierra Leone, by assessing environmental swab specimens for evidence of contamination with Ebola virus by RT-PCR. Swabs were collected following discharge of Ebola Virus Disease (EVD) patients before and after routine decontamination. Prior to decontamination, Ebola virus RNA was detected within a limited area at all bedside sites tested, but not at any sites distant to the bedside. Following decontamination, few areas contained detectable Ebola virus RNA. In areas beneath the bed there was evidence of transfer of Ebola virus material during cleaning. Retraining of cleaning staff reduced evidence of environmental contamination after decontamination. Current decontamination procedures appear to be effective in eradicating persistence of viral RNA. This study supports the use of viral swabs to assess Ebola viral contamination within the clinical setting. We recommend that regular refresher training of cleaning staff and audit of environmental contamination become standard practice at all Ebola care facilities during EVD outbreaks.     

Health seeking behavior after the 2013–16 Ebola epidemic: Lassa fever as a metric of persistent changes in Kenema District,Sierra Leone

BackgroundThe West African Ebola epidemic of 2013–2016 killed nearly 4,000 Sierra Leoneans and devastated health infrastructure across West Africa. Changes in health seeking behavior (HSB) during the outbreak resulted in dramatic underreporting and substantial declines in hospital presentations to public health facilities, resulting in an estimated tens of thousands of additional maternal, infant, and adult deaths per year. Sierra Leone’s Kenema District, a major Ebola hotspot, is also endemic for Lassa fever (LF), another often-fatal hemorrhagic disease. Here we assess the impact of the West African Ebola epidemic on health seeking behaviors with respect to presentations to the Kenema Government Hospital (KGH) Lassa Ward, which serves as the primary health care referral center for suspected Lassa fever cases in the Eastern Province of Sierra Leone.Methodology/Principal findingsPresentation frequencies for suspected Lassa fever presenting to KGH or one of its referral centers from 2011–2019 were analyzed to consider the potential impact of the West African Ebola epidemic on presentation patterns. There was a significant decline in suspected LF cases presenting to KGH following the epidemic, and a lower percentage of subjects were admitted to the KGH Lassa Ward following the epidemic. To assess general HSB, a questionnaire was developed and administered to 200 residents from 8 villages in Kenema District. Among 194 completed interviews, 151 (78%) of respondents stated they felt hospitals were safer post-epidemic with no significant differences noted among subjects according to religious background, age, gender, or education. However, 37 (19%) subjects reported decreased attendance at hospitals since the epidemic, which suggests that trust in the healthcare system has not fully rebounded. Cost was identified as a major deterrent to seeking healthcare.Conclusions/SignificanceAnalysis of patient demographic data suggests that fewer individuals sought care for Lassa fever and other febrile illnesses in Kenema District after the West African Ebola epidemic. Re-establishing trust in health care services will require efforts beyond rebuilding infrastructure and require concerted efforts to rebuild the trust of local residents who may be wary of seeking healthcare post epidemic.     

Assessment on the Knowledge and Reported Practices of Women on Maternal and Child Health in Rural Sierra Leone: A Cross-Sectional Survey

Background

Globally, Sierra Leone is ranked among the countries with the worst maternal and child health indicators. The mortality of women and children is significantly higher compared with other developing countries. The death of women and children can be prevented by simple cost-effective community-based interventions. The aim of this present study was to learn the knowledge levels of women on maternal and child health, and treatment-seeking and preventive behaviours in rural Sierra Leone and provide appropriate suggestions for policy makers. Moreover, the study also aimed to evaluate the effect of a husband’s involvement on health knowledge and practices of women in rural Sierra Leone.

Methods

Women with at least a child of five years or below were interviewed in their households through a structured questionnaire. Characteristics of the households and of the respondents were collected and the number of correct answers given to the health knowledge and practice questions and their percentage distributions were tabulated and an overall health knowledge score was calculated.

Results

The mean score of the derived overall health-related knowledge was 61.6% (maximum of 91% and a minimum of 18%) with a standard deviation of 14.7% and a median of 63.3%. Multivariable regression analyses showed education and number of pregnancies are associated with knowledge score, with significantly improved health knowledge scores amongst those who accessed higher education. There were some inappropriate practices in hygiene and sanitation. However, vaccination coverage was high with almost 100% coverage for BCG.

Conclusions

Based on the findings of this study, women’s knowledge on maternal and child health care are inadequate in rural Sierra Leone. Health promotion activities focusing on prevention of diarrhoea, malaria and pneumonia, improvement in health-related knowledge on pregnancy, delivery, neonatal care and environmental sanitation would be invaluable.     

Polymorphism and population density in Donax mgosus (Lamellibranchiata: Donacidae)

Donax rugosus is a common member of the intertidal fauna on wave-beaten sandy beaches in West Africa. In Sierra Leone, the animals breed during December and the shell grows about 3 mm a year to 24 mm after seven years. All populations studied are polymorphic with respect to shell colour, more so in Sengal than in Sierra Leone. Both the relative frequency of the white form and the total number of forms present in the same population increases with population density. There is little indication of significant differences in the relative frequency of colour forms in different year groups from the same population. The polymorphism is therefore assumed to be fairly stable at least over the short term.